If you have been keeping up with the SMURF news so far this summer, you may have noticed a trend – we haven’t been catching many fish lately. With less than two dozen fish caught in the last three weeks, one might start to wonder what causes lulls in fish recruitment? For the SMURF team, catching few fish is just as informative as catching many. As discussed in previous posts, the low numbers in the SMURFs are in line with what we expect for this time of year. But why do we expect to see so few fish during this time of the summer? It’s the height of tourist season, why shouldn’t it also be the height of fish recruitment season?
When fish settle is highly dependent on reproduction schedules. A high proportion of the fish we collect in SMURFs are rockfishes of the genus Sebastes. Rockfishes are somewhat unusual in their method of reproduction. Many fish reproduce through external reproduction, where males and females release sperm and eggs into the water column or onto rocks. Rockfishes, however, utilize internal fertilization, so that embryos develop inside females, who then release many living larval fish all at the same time. Some species release over 100,000 larvae at once! These larvae are generally microscopic, and we do not monitor them via SMURFing. However, over the span of a few months, the larvae grow and develop into the juveniles we collect in SMURFs.
Timing is Crucial
The crucial element of this cycle is timing. Different species give birth at different times of the year. For example black rockfish release their larvae mostly between February and May. The larvae spend about 3-6 months in open water before settling nearshore in the early summer months of May and June. Coincidentally, this is when we tend to see the biggest pulses of OYTBs (a group of species including black rockfish) in the SMURFs. For example, in early June of this year 426 OYTBs were collected at Redfish Rocks Marine Reserve! As time passes, black rockfish grow and move to deeper waters, below the SMURFs. Thus, we see fewer as the summer goes on.
Figure 1. A brief lull can be seen in early July in this SMURF data from 2016. It shows the transition from collecting one species group to the next and goes from OYTBs (olive, yellow, and black rockfish) to QGBCs (quillback, gopher, black-and-yellow rockfish).
Conversely, quillback rockfish tend to release their larvae later, between the months of April and July. While we’re hauling in OYTBs in the early summer, quillbacks are still too small for collection. After a few months in the water column, they begin to settle later in the summer around late July to August. In many years, QGBC (species grouping including quillbacks) pulses have occurred towards the end of July and through the months of August and September. Our greatest haul of QGBCs occurred in September of last year at Otter Rock Marine Reserve when 257 were collected!
The OYTB-QGBC transition, in the graph below, is a perfect example of how reproductive schedules are partially responsible for the mid-summer lull. A similar pattern can be described for other species, such as the cabezon-splitnose/redbanded (SR) transition. Cabezon (which reproduce via external fertilization), spawn in the winter between November and March. After a few months in the water column, juveniles are collected in greatest numbers at the beginning of the summer. Splitnose and redbanded rockfishes (the two members of the SR species grouping) don’t tend to release larvae until spring. We sometimes see huge pulses of these species in late summer, including an enormous pulse of 538 SRs in September 2013!
Figure 2. This data from 2015 illustrates another species transition as the summer progresses. This transition is from collecting more cabezon to an increase in the SR group (splitnose and redbanded rockfish).
This Week’s Summary
SMURFing this week returned slightly fewer fish than that outing in 2013. In total, 3 fish were collected – 1 cabezon and 2 clingfish – from Otter Rock. Conditions were some of the roughest we’ve encountered according to a seasoned SMURF veteran, with steep waves and substantial currents. However, thanks to expert piloting by the boat captain of the Shearwater, strong swimming by the snorkelers, and plenty of help from the deck crew, SMURFing went off without a hitch. Just another day at the SMURFfice. It’s possible that oceanic conditions could affect the number of fish collected, so we assess current flow at each SMURF. Other factors that may contribute to the midsummer lull include upwelling and variation in reproductive patterns between years. As more and more data are collected from year to year, our understanding of when fish show up in the SMURFs will continue to grow.
Otter Rock Marine Reserve, looking south from Cape Foulweather.
If you’re hungry for more SMURF knowledge. You can check out this leaflet, or look back at our previous SMURF posts about the SMURFers, fish sampling, and researching the reserves. And make sure to keep coming back in the upcoming weeks for more awesome SMURF science!
Love, Milton S., Mary M. Yoklavich, and Lyman K. Thorsteinson. The Rockfishes of the Northeast Pacific. Berkeley: U of California, 2002. Print.
O’Connell, Charles P. “The Life History of the Cabezon Scorpaenichthys Marmoratus.” 1953. State of California Department of Fish and Game Marine Fisheries Branch Fish Bulletin 93. Online Archive of California. Web.
Much of the information on SMURFs to date has focused on rockfish, but rockfish aren’t the only fish that we collect in the SMURFs. While rockfish may make the headlines with their huge pulses and interesting seasonal recruitment patterns, there is one reliable species which appears in the SMURFs nearly every week – the Cabezon. Cabezon, members of the sculpin family, are the third most frequently collected species in the SMURFs, and the most prevalent non-rockfish species. Here we’ll shine the spotlight on the Cabezon, a species which has often been overlooked in the past.
Juvenile cabezon collected with SMURFs.
Perhaps the main reason Cabezon are overlooked is because natural selection has shaped them specifically for this purpose. Cabezon blend in well with their surroundings due to the mottled pattern of their skin. Adults are sit-and-wait predators who lie on the bottom waiting for prey to draw near enough for an ambush attack. Prey, for Cabezon, is a very broad term. All sorts of crustaceans, fishes, and mollusks may find themselves inside a Cabezon’s stomach. Cabezon, in turn, may find themselves inside the stomachs of larger fish, seabirds, marine mammals (e.g. sea lions and seals), and humans. Originally, Cabezon may have served as an important food source for Native Americans living in the Pacific Northwest. However, when Europeans made it to the West Coast, they originally shunned the species as a food source. The main reason for this? Frankly, they thought it was too ugly to eat. Cabezon, though possibly slightly offended, probably didn’t mind being called ugly if it kept them off of dinner plates. Fortunately for fishers, and unfortunately for the Cabezon, the appearance stigma gradually diminished with the advent of live fisheries.
So how and why do these homely bottom-dwellers end up in our SMURFs? Cabezon don’t spend their whole lives on the bottom. In fact, their early years are an exciting journey from place to place before settling to the bottom. As mentioned last week, Cabezon reproduce via external fertilization. Females release thousands of eggs at a time onto the rocks in shallow waters during spawning season, which peaks in Oregon during the late winter. Interestingly, male Cabezon guard the eggs after fertilizing them until they hatch. The eggs themselves are poisonous and ignored by predators (including humans). With paternal protection and poisonous eggs, it’s quite impressive the lengths Cabezon have gone to defend their eggs. Once hatched though, larvae are at the mercy of the ocean for 3-4 months before settling into shallower waters. This is where they cross paths with the SMURFers.
Nearly 2000 Cabezon have been collected in SMURFs over the past 7 years of monitoring. As discussed last week, their reproduction schedule means the peak of Cabezon collection occurs in early summer, with a gradual decrease in numbers throughout the summer. A week without collecting a Cabezon is a rare one. Of the 91 SMURF outings conducted since 2011, approximately 90% of the trips have collected at least one Cabezon. Impressively, Week 12 of this year marked the first time a Cabezon was not collected at Redfish Rocks while SMURFing. You may recall from the Week 12 post that two SMURFs and two moorings were lost before this outing, so perhaps the streak would have continued had all the SMURFs been in action.
A long spawning season, large spawning populations, and favorable oceanic conditions all may play a role in the Cabezon’s persistent presence in the SMURFs. All that can be said with certainty is that, while Cabezon may not have the flashy reputation of some of Oregon’s other fishes, SMURFers are quite fond of these unsightly sculpins.
This week, the Cabezon returned to Redfish Rocks and a new streak began! The three fish collected in the SMURFs were all Cabezon; it seems the midsummer lull is still in full swing. However, in addition to collecting, this week’s outing was also a maintenance mission. With the assistance of one of our commercial fisherman collaborators and his vessel, we were able to deploy replacement moorings. The full fleet of SMURFs at Redfish Rocks is officially back online and ready for action!
Excited to see how this new fleet fares? Keep checking back weekly for updates on SMURFing at both Redfish Rocks and Otter Rock Marine Reserves!
Earlier this week, our intrepid team of SMURFers went out on the Oregon Coast Aquarium’s boat RV Gracie Lynn. The collection returned 3 clingfish, 2 QGBCs, 1 OYTB, and 3 Cabezon (as a reminder, OYTB and QGBC are abbreviations for groupings of rockfish species that are difficult to distinguish as juveniles). As an added bonus, this week, for the first time ever, part of our SMURFing expedition was streamed live on Facebook! You can watch the collection of one of the SMURFs in the video below. The video comes complete with commentary on the science of SMURFing as well as answers to some important SMURF questions, so check it out! Though only 9 fish were collected, they came from four species groups, making it a fairly diverse day of sampling. OYTBs remain the most collected fish in the SMURFs at Otter Rock so far this season. However, a pulse from one of our late-season-settlers could change that completely.
The Sultan of SMURF
One of those typically late-season-settlers which was absent from our collection this week, has also been one of the most commonly collected species in past years. You’ve heard of Babe Ruth, the so-called Sultan of Swat. Well our very own Sultan of SMURF knocks it out of the park with its historically high collection numbers. Unlike last week’s Cabezon, though, this species is not present in every sample. Some weeks, it appears in massive numbers! But most weeks it is completely absent. You might say this species is a little two-faced, a description which hits it right on the nose. That’s right one of the species that may be swamping the SMURFs soon is none other than the Splitnose Rockfish.
splitnose juvenile
The adult Splitnose Rockfish reaches a maximum length of 18 inches and is identifiable by the notch in its upper jaw, which also gives the fish its name. The purpose of this adaptation is unclear, but may have something to do with their diet. Splitnose primarily eat crustaceans in the midwater and above the ocean floor. As adults these fish are deep-dwellers normally residing between 500 and 1500 feet, and ranging as deep as 2600 feet! Like many other fish species, Splitnose spend their larval stage drifting in the ocean before reaching juvenile size. These juveniles often form large schools around floating mats of kelp, or around our SMURFs! Redbanded Rockfish also have been found to congregate around kelp mats as juveniles, and both are often found in the same SMURF sample. Since the two are nearly indistinguishable as juveniles, we treat them collectively as the SR species grouping. The huge pulses of SRs we have seen demonstrate the success of the SMURFs in imitating suitable habitat for juvenile fish.
Though SRs have been collected in huge numbers, they are anything but consistent. SRs have only been collected on about 25% of the SMURF trips. They are also late settlers, never collected in the SMURFS before July 1st. The tale of the Splitnose is one of booms and busts. In 2014 at Redfish Rocks, not a single SR was collected all season. The following year at the same site, nearly 900 were caught! The late peaks of the SRs are explained by their reproductive timing. The boom and bust pattern of their settlement is more complicated, but probably hinges on oceanographic conditions which can vary from year to year. So far in 2017 we have not collected any SRs. That could change, though. More than 80% of the SR specimens have been collected after August 11th, the day this story was posted, so stay tuned!
Keep checking back here for more awesome SMURFing information. When will the midsummer lull end? Are we in for a huge pulse of SRs? All these questions and more will be answered in the upcoming weeks!
References:
Love, Milton S., Mary M. Yoklavich, and Lyman K. Thorsteinson. The Rockfishes of the Northeast Pacific. Berkeley: U of California, 2002. Print.
Love, Milton S. Certainly More Than You Want to Know About the Fishes of the Pacific Coast: A Postmodern Experience. Really Big Press, 2011.
The past few weeks of SMURFing at Redfish Rocks have been nothing if not eventful. With all of the lost SMURFs and moorings, it’s almost as if there’s been a curse on the SMURFs. Thankfully, though there are signs that the SMURse is lifting (knock on wood!). After a month of issues, all eight SMURFs were successfully sampled this week for the first time since June 19th! The collection this week included 2 cabezon, 1 snailfish, and 4 QGBCs. These were the first QGBCs collected from Redfish Rocks since May. Could they herald the coming of a pulse? Only time will tell. Though the end of the SMURF season is on the horizon, there still is plenty of time for our late-summer-settlers to come in. Years of research have taught us that recruitment is highly variable. The Redfish Rocks QGBC pulse has come as early as mid-July in 2015, or as late as mid-September in 2016.
What’s in a SMURF?
Though the SMURF team still eagerly waits for an upcoming pulse, we can’t help but feel a bit of relief after this week. Building and deploying a SMURF is no easy task. Doing it over and over again to replace lost SMURFs and moorings takes a lot of work. So how does one make a SMURF? The materials are simpler than you might imagine.
A SMURF itself is nothing more than plastic fencing folded into a cylinder, stuffed with plastic snow fencing, and fastened together with a boatload of zip ties. Attaching it to its mooring requires some plastic tubing and halibut clips, but overall, the SMURF design is quite simple. More complicated is actually the design of the mooring itself. To ensure that SMURFs don’t drift away and remain one meter below the surface, a complex array of ropes, crablines, shackles, fancy knots, and buoys are employed. At the base of all of this is a 150 pound anchor made from recycled ship anchor chain to hold the whole thing in place.
This anchor holds the SMURF firmly in place.
Deploying this apparatus is sometimes accomplished with the help of our fisherman collaborators who can use commercial pot haulers to release the mooring over the side of their boats. Once in the water, the SMURFs are at the mercy of Mother Nature! The ocean is extremely powerful and can undo the best laid plans of SMURFers and men, as we have seen. Thankfully, all of our SMURFs are once again in action and hopefully will remain that way through the end of the season!
Keep checking back on the SMURF blog for more information about how the SMURFs are faring! Every new week could be the one that finally brings the big pulse, don’t miss it!
The countdown is on! Week 17 marked the third to last SMURF sampling trip this summer, and it certainly was an eventful one.
This week’s trip was the first SMURF voyage for Sara, our newest SMURF team member who is an Oregon State graduate student, as well as the last voyage for Madeline and Zach, two of our summer SMURF team interns. So a big welcome to Sara! And to our departing SMURFers, good luck, and thank you for your SMURvice. Rookie and veteran alike were treated to a brilliant display of Oregon’s wildlife. Our research boat, the Shearwater, was escorted out of Yaquina Bay by a couple of curious sea lions. Once it reached the Otter Rock Marine Reserve it was greeted by a group of gray whales! The whales watched over our SMURFers as they took to the water at a couple of the SMURF sites.
Left to Right: Zach Clemens (Sea Grant intern), Maddie Musante (OSU intern) and Will Fennie (OSU phD candidate) ride back to port after a day of SMURFing.
The SMURFs themselves held numerous nudibranchs, a collection of caprellids (shell-less crustaceans in the order Amphipoda), and countless young crab! The only thing lacking was a nice pulse of juvenile fish. We collected 1 snailfish, 1 clingfish, and 2 cabezon. At this point it is safe to say that the mid-summer lull is no longer just a mid-summer lull. With only one more sampling trip at each site, we are definitely well into the late-summer now.
Otter Rock Roundup
Our second to last sampling at Otter Rock provides a good opportunity to look back at this site’s summer SMURF season. So far our collections have yielded a total of 259 fish at Otter Rock. Through 7 years of sampling at this site, this total ranks 4th overall. Last year’s 1,355 fish runs away in first place, while the 46 fish collected in 2011 brings up the rear. This gives some sort of an idea of how 2017 has compared to years past. However, it is important to note that total number of fish is not a perfect measurement of recruitment from year to year. The SMURFs are not always in the water for the same exact length of time. Some years we’ve sampled as early as April, some years we haven’t sampled until June. Additionally, variation in the number of SMURFs in the water from week to week could affect counts. For example, this year at Otter Rock we weren’t able to successfully sample all eight SMURFs until the beginning of June. For the first month of the summer, bad weather meant there were only 5-7 SMURFs in the water at a time. It is important to control for the length of the sampling period and the number of SMURFs in the water when analyzing the data scientifically.
Another issue in relying only on total counts is that this doesn’t reflect differences in recruitment between species from year to year. Certain species settle in greater numbers than others, but the species with the greatest recruitment can vary from year to year. Our most popular species in the SMURFs at Otter Rock so far in 2017 has been the OYTB species grouping (Olive, Yellowtail, and Black Rockfish), with 90 collected. In second is the Clingfish with 75, followed by the Cabezon with 42. OYTBs and Cabezon are often among our most collected species at Otter Rock. However, one species that we are used to seeing in larger numbers is the QGBC species grouping (Quillback, Gopher, Black-and-yellow, China, and Copper Rockfishes). Last year, QGBCs were the most collected species by a landslide. This year, we’ve collected 8. The late-summer QGBC pulse has not yet arrived this summer, and we are waiting to see when and if it will. There are a multitude of possible reasons why we’re seeing this pattern. Perhaps ocean currents took this year’s recruits elsewhere. Perhaps QGBC reproductive timing was later this year. We simply don’t know, yet. However, this is a great example of why the SMURFs are so important! SMURFing in Oregon’s Marine Reserves has provided us with incredible new information about the reproduction and development of juvenile fishes, and when the ocean delivers them to the nearshore. Prior to SMURFing in Oregon, we had no inkling of how complicated and variable the process of recruitment can be in this area. Now as we become aware of this, new questions continuously emerge. As SMURFing continues in the future, we’ll be able to address some of these questions and learn more and more about how juvenile fish are using Oregon’s oceans.
There are only two more weeks of SMURFing this year, which means only two more SMURF blogs! Keep checking in right up until the very end for updates on our last sampling outings!
Towards the end of July, an oceanic buoy located in Cape Perpetua Marine Reserve showed a drop in ocean oxygen levels. Around the same time, about 20 miles north, ODFW Marine Program crab biologists pulled up a research crab pot filled dead crabs. The crab pot was equipped with a video camera and the biologists likely caught an oceanic phenomenon on camera – crabs succumbing to a low oxygen, or hypoxic, event. Hypoxia is when oxygen levels in the water drop below the level that can be fatal to many marine organisms, and occurs periodically off the Oregon coast.
ODFW researchers suspect that the crabs likely succumbed to low oxygen conditions during an oxygen decline. During the first week, the water was clear and crabs were active. But, over the next week, water clarity dropped, and crab activity slowed. By the fifteenth day, all signs of life were gone. Cape Perpetua oceanic buoy data Oregon State University (OSU) corroborated that oxygen levels were low and showed that the dates of the crabs’ demise corresponded with a hypoxic event.
Hypoxia off Oregon’s nearshore waters was first documented in 2002. During this time, ODFW researchers used underwater video to conduct research on a reef normally filled with life, and instead found it devoid of fish except for a few dead ones on the bottom. At that same time, commercial crabbers noticed dead crab in a nearby area. Soon afterward, OSU researchers visited the area and measured very low oxygen levels in the water, confirming hypoxia.
Hypoxia off of Oregon occurs when several oceanographic, weather, and biological phenomena coincide to create the low oxygen conditions. This differs from other areas of the country, such as the Gulf of Mexico, where hypoxia is caused primarily by water pollution. Off of Oregon, summer northwest winds cause deep water offshore from the continental shelf to be upwelled onto the shelf and toward shore. This deep water contains abundant nutrients and is naturally very low in oxygen.
High nutrients levels cause an explosion of phytoplankton life (small single-celled plants in the water). As the phytoplankton die, they settle to the bottom and decompose. This causes further oxygen decline in the near-bottom waters which were already low in oxygen. This can be exacerbated even further when winds decrease and the deeper water becomes more sluggish and is less likely to be mixed with oxygen-rich surface water.Many marine organisms either move from the area, or die when dropping oxygen levels reach a critical point. Once the phytoplankton bloom ends and water begins to mix, oxygen levels return to normal.
Since 2002, hypoxia has been documented several times off of Oregon in the summer and fall months. While hypoxia is a natural phenomenon off of Oregon, researchers suspect that climate change is increasing the frequency and severity of hypoxia events.
As the SMURFing season winds down, the team has faced some last minute challenges in sampling the SMURFs at both the Otter Rock and Redfish Rocks sites. On the first attempt at Redfish Rocks in late August, the seas were just too rough to get out on the water. The second attempt got the SMURFers on the water, but then they were chased off shortly by… a LIGHTNING storm! – not a common sight in Oregon’s nearshore! (And not something you want to be out on the water for!) Attempt number three will happen this week. We will report on the success as soon as possible.
The last SMURF at Otter Rock was picked up on September 15th. We’ll start SMURFing again in April 2018.
The sampling at Otter Rock last week was a success in that all the SMURFs were there, yet they only yielded 3 fishes total: two Cabezon and one Clingfish. The SMURF team was able to repair and replace some of the surface floats that mark the moorings and keep them upright. The team will head back out for the final SMURF sampling at Otter Rock before the incoming wind and swell have any chance to wipe out the last haul of the season.
Check back in next week to see how the season ends! As we pull out the moorings for the upcoming Oregon winter seas, we’ll reflect back on all we’ve learned throughout this thrilling (harrowing?) 2017 season!
As the SMURF 2017 season ends, we are looking back at what turned out to be quite a tumultuous year! Although the SMURF moorings were deployed early in April, they endured a rough spring welcoming and some were lost early on. As a calm summer approached, the losses were replaced and sampling continued. Then, as the time drew near to remove the moorings for the rough Oregon winter, season transition storms (some even with lightning!) caused even more mooring replacements in the last month.
Retrieving the mooring that anchors the SMURFs.
Curious to see if there would be a large recruitment of Splitnose/Redbanded Rockfish and the QGBC-complex (we group some species of rockfish recruits), we kept the SMURFs in the water as long as weather and budgets would allow. The last SMURFs from Otter Rock and Cape Foulweather were pulled up on Monday, using the great strength of the Oregon State University’s research vessel Elakha.
In 2017, the numbers are very different from 2016. Total counts of the most common species for all sites combined, over the past two years.
This is what makes these long-term data sets so valuable: to see how different fish species recruit in different years. As we see changes throughout time, we can look at ocean chemistry, currents, and food sources to begin to tease out why these changes might occur. Oregon’s Marine Reserves make an excellent venue for long-term research projects like SMURFing.
Check back with us next April to see what 2018 will bring to the SMURFs!
Like nettle plants on land, these Pacific sea nettles can leave a similar sting. Recently, ODFW habitat researchers ran into swarms of these guys while doing acoustic marine habitat surveys just south of Cascade Head Marine Reserve (see the video below). Over the last month, marine reserves researchers have seen sea nettles during SCUBA dive and video lander surveys at several reserves.
Sea nettles tend to be more abundant when ocean productivity is high – and this year’s big upwelling helps explain why they are more common right now (there’s lots of food in the water for them to eat). Interestingly, researchers have noticed higher sea nettle numbers this past spring, relative to 2016. The lower sea nettle numbers last year were likely a byproduct of the warm water ‘Blob’ that resulted in less productivity off our coast.
Sea anemones dot the tidepools and rocky reefs in and around Oregon’s marine reserves, and look more analogous to flowering plants than the predatory animals that they actually are. SCUBA surveys shed light on 8 species that have subtidal populations in the reserves, with the most common being the giant plumose anemone.
We invited guest author, filmmaker and photographer, Stephen Grace, to share his fascinating perspective on sea anemones in Oregon.
By Stephen Grace – author, filmmaker and photographer
The sea anemones that paint Pacific Northwest tidepools with color look like tranquil flowers but are, in fact, predatory animals. Cousins of jellyfish, coral, and siphonophores like the Portuguese man o’ war, anemones are in a group of marine creatures that have tentacles packed with poisonous stinging cells to paralyze and kill their prey. Deadly beauties of the intertidal zone, anemones not only eat animals. They also battle for territory, even engaging in wars with rival colonies over contested terrain.
As large as a tea saucer and sometimes growing to nearly the size of a dinner plate, the giant green anemone (Anthopleura xanthogrammica) will devour almost any creature careless enough to stray too close to its sticky tentacles, or to tumble into its emerald clutches. The tentacles fold in toward the anemone’s mouth; the mouth gapes open and protrudes toward the paralyzed victim. If a giant green anemone grew six feet wide and lurked beneath pools where people play, Stephen King could not create a more horrifying scenario.
Giant green anenome eating a jellyfish (Photo by Stephen Grace).
Anemones can release their grip on a hard surface and move their pedal discs like ponderous feet, creeping their way across a rock. Occasionally they detach themselves and float away to reattach to a new surface, but generally these predators remain anchored in place. Giant green anemones often station themselves beneath mussel beds bashed by waves; the anemones devour bivalves knocked loose that fall into their lethal grasp. Urchins and snails that tumble downward also become a meal. Crabs that brush an anemone’s sticky tentacles are grabbed and eaten, and fish that swim too close are imprisoned in a deadly embrace. Giant green anemones even eat birds. Young cormorants and gulls that tumble into pools below their nests have been devoured by these stationary assassins.
Whatever hard animal parts an anemone can’t digest, such as bones, beaks, shells, and spines, are expelled through the opening at the anemone’s center. This orifice is both mouth and anus. Though odd to us, this multitask plumbing serves the anemone well. Hermit crabs have no complaints about this anatomical curiosity, either. An empty snail shell spat out of an anemone’s mouth-anus, after the mollusk inhabitant has been digested by the anemone, makes a choice home for a hermit crab. The blue-banded hermit crab performs a dangerous dance, walking across the tentacles and mouth of a giant green anemone without being eaten as it waits for a turban snail shell to be ejected.
The giant green anemone uses its stinging cells for defense as well as for feeding. Anemones eat some species of snails; some snail species eat anemones. Wentletrap, from a Dutch word meaning “spiral staircase,” is a family of snails with beautifully spiraled shells that seem sculpted of porcelain. But these elegant mollusks are anemone killers. Some wentletraps snip the anemone’s tentacles; others spear a long proboscis, or feeding tube, into the anemone’s soft column. An anemone might be digesting a wentletrap relative, like a black turban snail, while the anemone is attacked by the wentletrap. Every pool at the ocean’s edge contains a complicated world of competition and predation.
The shaggy mouse nudibranch is another enemy of the anemone. This sea slug looks like a little bedraggled rodent when stranded out of the water. The shaggy mouse is immune to an anemone’s poison and attacks the creature underwater, dining on the anemone’s stinging tentacles. The leather sea star is another anemone predator. Additionally, some sea spider species feast on anemone flesh. Though not true spiders, these arthropods are part of a tangled web of creatures eating and being eaten along the water’s edge. There are no pacifists in the ferociously competitive tidepools.
Giant green anemone and leather sea star (Photo by Stephen Grace).
It’s not all cutthroat competition between the changing tides, however. Giant green anemones have a symbiotic relationship with algae. Algae that live inside the anemones are protected from grazers like snails. In exchange for being safely housed, the photosynthesizing algae provide their hosts with carbohydrates, contributing a significant portion of the calories to an anemone’s diet.
The brilliant color of the giant green anemone is attributed both to the algae it hosts and to a sunscreen it produces. Green fluorescent protein prevents solar radiation from damaging the anemone’s body by absorbing ultraviolet light and emitting lower-energy green light. This fluorescence contributes to the giant green anemone’s dazzling hue.
The color of giant green anemones varies with exposure to sunlight. Anemones lurking below shadowy ledges and hidden in caves can be as grey as ghosts, while not far from these pale zombies, which are smaller and more sickly than their colorful counterparts, robust anemones bask in direct sunlight. Anemones that are showered with light shine fluorescent green, as if painted by an artist on magic mushrooms.
An anemone that withdraws its tentacles when stranded above the water is transformed from a tidepool beauty into a repulsive beast. People who wax lyrical about an anemone beneath the sea wrinkle their faces in disgust when the same creature becomes a blob dangling from a rock. But what looks repulsive to us is an adaptation that allows the anemone to avoid drying out. The less surface area that is exposed to air and sun, the more moisture the squishy creature retains when the tide is out. The anemone pulls its pretty oral disk and tentacles into its column, holding a bit of the sea inside its sagging body until the tide returns.
The symbiosis between giant green anemones and algae, though not as showy as the famous partnership between anemones and clown fish, runs deep. Like nearly all other animals, anemones inhale oxygen and exhale carbon dioxide. The algae inside an anemone’s body combine water and sunlight with the carbon dioxide exhaled by the anemone to create carbohydrates, and these sugars feed the anemone. In return, a sea anemone swivels its body toward the sun, providing the algae inside its cells with light for photosynthesis.
Algae, in turn, release oxygen as a byproduct of photosynthesis. The oxygen is inhaled by the anemone to fuel its respiration, and this oxygen-powered respiration releases the energy stored in carbohydrates—which were produced by the algae and consumed by the anemone. It’s hard to imagine a more mutually beneficial partnership.
The giant green anemone may also help humans. A toxic compound that the animal produces to defend itself from predators acts as a potent heart stimulant in vertebrates. Medical researchers are studying this compound, anthopleurin, for its potential to treat patients with heart failure and liver injury.
Anemones might even help scientists solve the riddle of eternal youth. Their powers of regeneration are remarkable. If an anemone is torn apart, each part will heal and become a complete animal. Anemones have been documented to live one hundred years, but scientists believe they can live much longer. Some researchers posit that these methuselahs of the tidepools are, in fact, functionally immortal. That is to say, as long as anemones are not poisoned or eaten, these creatures with a primitive nervous system but no brain will go on living, showing no signs of the cellular degeneration that kills people. No tumors, no cancer, no death: somehow anemones avoid these human plagues of aging. If we don’t kill off anemones first by poisoning their waters, these deadly beauties may offer us the key to immortality.
Aggregating Anenome
The aggregating anemone (Anthopleura elegantissima) covers rocky surfaces by cloning itself. A pioneer anemone founds a new colony by dividing in half. It stretches like taffy, pulling its body in opposite directions until it breaks into two pieces. Each half regenerates into a complete anemone with an identical copy of DNA. One anemone becomes two identical anemones, two become four, and so on, until clones blanket a surface.
Aggregating anemone (Photo by Stephen Grace).
Multiple copies of one genetic individual help ensure survival amid the violence of the intertidal zone. Flood and drought cycle daily, salinity and temperature fluctuate wildly, and the creatures that inhabit this brutal world are battered by waves and scorched by sun as they evade predators and struggle for scarce space and limited food.
“Strength in numbers” could be the motto of an aggregating anemone that clones itself into hundreds of copies. This redundancy is a neat survival trick, and also makes great fodder for science fiction. Imagine you could emulate an aggregating anemone and clone multiple copies of yourself. If all but one of the cloned copies perished, and the original you was also killed, would you still be alive? For the aggregating anemone, the answer is a resounding yes.
Watching anemones clone themselves is like seeing cells divide under a microscope, but the process stretches over a span of many hours and days. There is drama in an anemone’s world, but the action unfolds on a timescale that requires patience—or time-lapse photography.
Aggregating anemones that are genetically different get along like Hatfields and McCoys. When spreading colonies of clones collide, warrior anemones at the borders react. The warriors triple their body length as they reach toward foreign clones encroaching on their space, and the warriors deploy armaments, extending stout battle clubs that fire barrages of poisoned missiles at the colony’s rivals.
As anemones sustain damage in these territorial skirmishes, they loosen their grip on the hard surface and slink away from their attackers. In the aftermath of a clone war, bare rock emerges between colonies. These no-clone-zones are clearly visible as strips of bare rock an inch or two wide between densely packed colonies that otherwise completely cover a rocky surface.
The clones in an aggregating anemone colony are genetically identical, yet they take on specialized roles. Surrounded by warrior clones, the reproductive clones in the colony’s center reproduce sexually. Each colony is composed of either all male clones or all female clones. These reproductive clones broadcast eggs or sperm, depending on their sex, and the gametes mix in the water.
The reproductive clones of two colonies that are mortal enemies battling like Montagues and Capulets can, like star-crossed lovers, blend their genes and create larval anemones. These spawn of warring nations move through the water to settle on rocky frontiers, and they create new colonies of their own, carrying forward the endless cycle of cloning, sex, and combat beneath the sea.
Some clones turn into scouts, venturing into unknown territory beyond the colony’s borders. When a scout returns, its colony can detect if their explorer was attacked during its journey into uncharted territory. If the scout was stung by warriors of another colony, the scout’s clonemates can sense that a rival colony is nearby.
When I learned about clone wars, my interest in the intertidal zone exploded. After reading about aggregating anemones, I explored the ocean’s edge for evidence of battle. When I saw a demilitarized zone of unoccupied rock separating two competing colonies, my mind was blown wide open. I grew determined to see enemy anemones in action.
After a few weeks of searching tidepools, I spotted warriors extending their white acrorhagi, the war clubs they inflate when fighting rival colonies. When I stooped down to stare into the tidepool that sheltered these combative creatures, I witnessed a war taking place on multiple fronts as colonies blanketing a boulder battled each other for territorial supremacy. Anemone nations rose and fell that day as I slithered on my belly across sand to watch this Game of Thrones play out beneath the surface of the pool. I’ve been hooked on the intertidal zone ever since.
Not all of the aggregating anemone’s adaptations are related to combating rivals for space. To protect itself from ultraviolet radiation, the creature has adhesive cells on the outside of its body that gather bits of shell and other debris from the seawater. On the rare occasion that the sun shines on the Oregon Coast, the anemone is prepared. The material covering its body reflects the sun’s rays, preventing this sea creature from drying out: anemone sunscreen.
Sand burial is a fact of life in the intertidal zone. Winter storms strip beaches down to bare boulders and cobbles; gentle spring and summer waves send the sand back to shore, burying anemones and other animals attached to rocks under several feet of sediment. Giant green anemones and aggregating anemones have adapted to this regular burial routine by evolving the ability to live off stored glycogen when they can’t feed during prolonged periods of entombment. When released from their sand prison, they spread their poisoned tentacles and resume feeding on prey and fluorescing in the sun.
Human inventiveness can seem feeble compared to the creative force of evolution through natural selection. When I was a kid I devoured science fiction. These days I don’t have time for imaginary stories because I’m too busy staring into tidepools, where I study lifeforms more bizarre than any creation conjured in the human imagination. Landscapes along Oregon’s shores can seem like scenes from other worlds. And there is nothing stranger in science fiction or fantasy than the real beings that live in the intertidal zone.
From hypoxia and strange creatures washing up on beaches, to jellyfish blooms, research collaborations with fishermen, and advancements in underwater video research tools – Oregon’s marine reserves were teeming with discoveries this year.
Here we take a look back at a few of our top videos and stories from 2017. You’ll also find our annual Marine Reserves Program highlights video and infographic.
1. Hypoxia – Towards the end of July, Oregon State University’s oceanographic buoy located in Cape Perpetua Marine Reserve showed a drop in ocean oxygen levels. This hypoxic (low oxygen) event ran from roughly mid-summer into the fall. Read more about what researchers found – including a video of what they saw while doing crab research.
2. Pyrosomes – In past years pyrosomes were rare finds on Oregon beaches. But in the winter of 2016 – 2017 they became as common as kelp in driftlines and in the spring they washed up in astounding numbers, awing beachcombers and spurring scientists to study why these creatures were appearing in unprecedented swarms. Read more about these strange creatures that are still washing up on Oregon’s beaches. And, here’s a video showing what biologists were seeing offshore and at the docks.
3. Fish and Invertebrate Spotlights – Many interesting species live beneath the ocean surface in our nearshore waters – from tiger rockfish, to cabezon nicknamed ‘mother-in-law’ fish (due to it’s large mouth and constant croaking). And, don’t forget the invertebrates. Here’s an interesting story on sea anemones, that look more analogous to flowering plants than the predatory animals that they actually are, along with information about our sea star surveys.
4. Policy and Management Highlights – On the policy front, the ODFW Marine Reserves Program underwent a 5 year review with the Science and Technical Advisory Committee; the technical arm of the Ocean Policy Advisory Council. We also took a deeper dive into the site management of Cascade Head with finalization of the Cascade Head Marine Reserve Site Management Plan.
5. Jellyfish Bloom – Besides pyrosomes and hypoxia, another oceanic oddity this year was a jellyfish bloom. Sea nettles are a type of jellyfish that tend to be more abundant when ocean productivity is high. Thanks to this year’s big upwelling there’s been lots of food in the water for them to eat. The lower sea nettle numbers last year were likely a byproduct of the warm water ‘Blob’ that resulted in less productivity off our coast. Click here for a video to see what researchers saw just south of Cascade Head Marine Reserve.
The Marine Reserves SCUBA Survey Team covered a large section of the coast this year. Hundreds of surveys were conducted in the Cape Falcon, Cascade Head, and Otter Rock Reserves, combined. These underwater surveys collect data on fishes, kelps, invertebrates, and habitats in depths up to 65 feet inside and near the Marine Reserves. The dive team is a dedicated group of volunteers from OSU, the Oregon Coast Aquarium, and other local science divers. Check out our end-of-year newsletter and infographic for some details on what they saw this year.
Patches of barnacles blanket the rocky surfaces in and around Oregon’s marine reserves, and hide fascinating life history secrets. We’ve invited guest author, filmmaker, and photographer Stephen Grace to share some of his photos and insights on barnacles with us.
By Stephen Grace – author, filmmaker and photographer
Scoured by waves and scorched by sun, the shells of gooseneck barnacles (Pollicipes polymerus) whiten in the intertidal zone. I tend to overlook these drab crustaceans that attach themselves to rocks and feed by filtering seawater. On rare occasions, however, I find gooseneck barnacles in sheltered stashes safe from direct sunlight and crashing surf, and their protected shells shine like gemstones. When I touch the jeweled shells, these relatives of crabs, lobsters, and shrimps swivel their leathery necks.
Unlike acorn barnacles (Balanus sp.) that encrust hard surfaces of the intertidal zone, gooseneck barnacles can bend their long necks back and forth. But all adult barnacles, whether acorn or gooseneck, are forever fixed in one location, head down and feet up.
Gooseneck Barnacle (Photo by Stephen Grace)
A barnacle begins its life as a larva that moves freely through the ocean. Unlike its crustacean cousins that continue their free-ranging lives, the barnacle becomes anchored in place, like a person who sows his wild oats and then settles down. How a barnacle settles is remarkable. It glues its head to a hard surface with a cement so strong it has inspired dental surgery adhesives. The creature’s feet metamorphose into feathery feeding appendages known as cirri. When submerged, a barnacle uses its cirri to comb the water, capturing plankton and tiny bits of dead matter.
The barnacle’s strategy of living on its head and eating with its feet allows it to survive predation by fish and other creatures. Barnacle cirri that are eaten can grow back; if the animal poked its head out of its shell instead of its feet, it would be killed.
After attaching itself to a hard surface, a barnacle builds a shell fortress it never leaves, becoming a prisoner in a calcareous castle. Though a barnacle has a hard exoskeleton like other crustaceans, its shell (or “test” as scientists prefer) provides extra protection from both predators and the elements. When the tide recedes, a barnacle pulls its cirri inside and closes up its shell with plates that shut like a trapdoor, shielding the creature from dry air and sealing in moisture. To prevent its body from drying out, a barnacle circulates the seawater stored within its shell, creating the crackling and popping sounds heard in sea caves and around rock walls when the tide is out.
Like all other crustaceans, a barnacle molts as it grows. Though its shell remains anchored in place, its body inside the shell sheds its exoskeleton. Barnacle molts that wash up in the driftline or sink to the bottom of tidepools look like reddish-amber shrimp.
Acorn barnacles anchor their shells directly to rocks or other hard surfaces. Gooseneck barnacles attach themselves to hard surfaces with peduncles—the flexible stalks that give the creatures their snakelike appearance. Peduncles allow gooseneck barnacles to aim their cirri into current when they feed. The pelagic gooseneck barnacle (Lepas anatifera), a species that attaches to logs and other flotsam that washes ashore, swivels its neck. Clusters of the stranded creatures sway back and forth, as if searching for the sea.
Adult barnacles secrete compounds that attract larvae, creating densely populated clusters. Living packed together in groups allows barnacles to fertilize each other’s eggs internally. Relative to their body size, barnacles have the largest penises of any animal—and every barnacle has a penis.
Barnacles are hermaphroditic: each creature has both male and female sex organs. A barnacle reaches over to inseminate its neighbor, using a penis that inflates up to eight times the length of its body—a different strategy from the method used by mussels. Like barnacles, mussels anchor themselves to hard surfaces and can’t move around to find a mate. Mussels, however, reproduce by broadcasting their eggs and sperm into the water to mix.
Scientists recently discovered that barnacles can change the size and shape of their penis to best suit the water conditions. Long, thin penises perform best in calm water; short, stout penises are optimal in turbulent seas. Less salacious but equally fascinating is the idea of barnacles as parents: they brood their fertilized eggs within their shells. Charles Darwin was so fascinated by barnacle reproduction that he studied the creatures on a daily basis for eight years before publishing his groundbreaking book On the Origin of Species.
Our annual Fish On! Hook-and-Line Volunteer Newsletter is now out with highlights from our 2017 surveys. This was our third year of hook and line surveys at Cape Falcon, and our sixth year of hook and line plus third year of longline surveys at Redfish Rocks. We saw 17 different fish species and collected data on 1,873 fish. The biggest fish caught was a 38 inch Lingcod and the smallest was a 5 inch Deacon/Blue Rockfish.
A big thank you from the ODFW Marine Reserves Program to all our volunteer anglers, research assistants, and vessel captains and crew that assisted with the 2017 surveys. We look forward to seeing our volunteers again next year for surveys at Cascade Head and Cape Perpetua.
Check out the Newsletter for more survey highlights and to learn a bit about our pilot fish tagging study at Redfish Rocks.
Numerous strange gelatinous creatures wash up on Oregon’s beaches every year – everything from jellyfish to strange pickle like organisms called pyrosomes. Today we wanted to highlight salps, are a lesser known group of organisms. We’ve invited guest author and photographer, Stephen Grace, to share this story and some of his photos on salps.
By Stephen Grace – author, filmmaker and photographer
Some of the gelatinous creatures that wash onto Oregon’s beaches are salps. Though salps resemble jellyfish without tentacles, they belong to a group of animals known as tunicates, commonly called sea squirts. In their larval phase, tunicates possess a primitive backbone structure, making salps more closely related to people than to jellyfish. Stranger yet, we are closer kin to a salp with its rudimentary spinal column than we are to an octopus, an invertebrate mollusk that seems almost humanlike with its playful personality and its remarkable memory, curiosity, and problem-solving skills. Sometimes I stare at a blob of salp goo on the sand and let the bizarre fact that we are cousins in the same phylum bubble in my brain.
Salp on Beach (Photo by Stephen Grace)
Salps look like lumps of limp gelatin when they’re stranded on the beach, but in the ocean these barrel-shaped creatures with openings at both ends contract muscle bands to pump water through their transparent bodies, moving by jet propulsion. When a salp pushes water in one direction, its body moves in the opposite direction in accordance with Newton’s third law: For every action, there is an equal and opposite reaction.
As these gelatinous rocket scientists pilot their way through the sea sucking in water and expelling it, they filter the water for the tiny phytoplankton they eat. Salps are also considered plankton. Even though they are much larger than the microscopic organisms they consume, salps are carried by currents stronger than their jet-powered motion. The word plankton comes from the Greek planktos, meaning wandering. As salps wander the sea grazing on algae, they provide a gelatinous feast for fish, seabirds, sea turtles, and siphonophores like the Portuguese man o’ war.
The salps we see on the beach represent one part of a strange lifecycle that involves both solitary salps and salp aggregations. A solitary salp reproduces asexually by budding a chain of clones that create light. The individual salps in a luminous chain remain attached as they swim; these strands of glowing strangeness can stretch more than fifty feet. The chains of some species form complex shapes such as giant wheels, and even a double helix. Salps that are linked together communicate through electrical signals to synchronize their movements, and a chain of harmonized beings pulses brightly as it snakes or spins its way through the sea.
When salps reproduce sexually, things really get interesting. Each member of a salp chain is a sequential hermaphrodite. A salp starts life as a female and then turns into a male. An older salp that has transformed into a male fertilizes a female; as a fertilized female grows older, it becomes a male that fertilizes a younger female. If salps could tell stories, oh the stories they’d tell.
A fertilized salp female broods her embryo, nourishing it through a placenta-like membrane until the young salp can survive on its own. After emerging from its mother, the salp grows into a solitary creature that buds its own chain of clones, which are sequential hermaphrodites that reproduce sexually. And so on, in one of the many mind-boggling lifecycles of creatures in the sea. We may one day travel to distant worlds and discover forms of life that don’t seem as otherworldly as a glowing, gender-bending salp chain using jet propulsion to travel Earth’s oceans as it feasts on the tiniest organisms in the sea.
Asexual cloning is an extremely fast form of reproduction. But cloning can lead to an evolutionary dead end because it doesn’t result in the genetic diversity that a species needs to adapt to changing conditions in the environment. Sexual reproduction creates genetic diversity within a species, but it’s a slow way to reproduce. Our salp cousins have arrived at a strategy that combines the best of both reproductive methods.
When food is abundant, salps clone themselves extraordinarily fast. Their populations explode to take full advantage of the bounty; staggering numbers of salps gobble up vast blooms of algae. A single swarm of salp clones can cover hundreds, or even thousands, of square miles. And because of the constant gene shuffling that comes with the sexual reproduction of salps, when the environment changes, some individuals have the genetics necessary to deal with the shifting conditions.
We have explored less of the ocean floor than we have the surface of Mars. Think of the strange beings yet to be discovered in the seas of our planet. There is no end to the weirdness beneath the waves, and each creature stranded on the shore tells a story of survival and adaptation in the watery world where our own species began.
The salps that wash ashore reflect and refract light in a dazzling display. Each gelatinous tunic acts as a sort of prism and lens, magnifying sand and breaking white light into bright colors. Who needs drugs when salps are washing up on the beach bearing rainbows in their alien bodies.
Numerous strange gelatinous creatures wash up on Oregon’s beaches every year – everything from jellyfish to strange pickle like organisms called pyrosomes. Today we wanted to highlight salps, a lesser known group of organisms. We’ve invited guest author and photographer, Stephen Grace, to share this story and some of his photos on salps.
By Stephen Grace – author, filmmaker and photographer
Some of the gelatinous creatures that wash onto Oregon’s beaches are salps. Though salps resemble jellyfish without tentacles, they belong to a group of animals known as tunicates, commonly called sea squirts. In their larval phase, tunicates possess a primitive backbone structure, making salps more closely related to people than to jellyfish. Stranger yet, we are closer kin to a salp with its rudimentary spinal column than we are to an octopus, an invertebrate mollusk that seems almost humanlike with its playful personality and its remarkable memory, curiosity, and problem-solving skills. Sometimes I stare at a blob of salp goo on the sand and let the bizarre fact that we are cousins in the same phylum bubble in my brain.
Stephen Grace: Salp at Sunset
Salps look like lumps of limp gelatin when they’re stranded on the beach, but in the ocean these barrel-shaped creatures with openings at both ends contract muscle bands to pump water through their transparent bodies, moving by jet propulsion. When a salp pushes water in one direction, its body moves in the opposite direction in accordance with Newton’s third law: For every action, there is an equal and opposite reaction.
As these gelatinous rocket scientists pilot their way through the sea sucking in water and expelling it, they filter the water for the tiny phytoplankton they eat. Salps are also considered plankton. Even though they are much larger than the microscopic organisms they consume, salps are carried by currents stronger than their jet-powered motion. The word plankton comes from the Greek planktos, meaning wandering. As salps wander the sea grazing on algae, they provide a gelatinous feast for fish, seabirds, sea turtles, and siphonophores like the Portuguese man o’ war.
The salps we see on the beach represent one part of a strange lifecycle that involves both solitary salps and salp aggregations. A solitary salp reproduces asexually by budding a chain of clones that create light. The individual salps in a luminous chain remain attached as they swim; these strands of glowing strangeness can stretch more than fifty feet. The chains of some species form complex shapes such as giant wheels, and even a double helix. Salps that are linked together communicate through electrical signals to synchronize their movements, and a chain of harmonized beings pulses brightly as it snakes or spins its way through the sea.
When salps reproduce sexually, things really get interesting. Each member of a salp chain is a sequential hermaphrodite. A salp starts life as a female and then turns into a male. An older salp that has transformed into a male fertilizes a female; as a fertilized female grows older, it becomes a male that fertilizes a younger female. If salps could tell stories, oh the stories they’d tell.
A fertilized salp female broods her embryo, nourishing it through a placenta-like membrane until the young salp can survive on its own. After emerging from its mother, the salp grows into a solitary creature that buds its own chain of clones, which are sequential hermaphrodites that reproduce sexually. And so on, in one of the many mind-boggling lifecycles of creatures in the sea. We may one day travel to distant worlds and discover forms of life that don’t seem as otherworldly as a glowing, gender-bending salp chain using jet propulsion to travel Earth’s oceans as it feasts on the tiniest organisms in the sea.
Asexual cloning is an extremely fast form of reproduction. But cloning can lead to an evolutionary dead end because it doesn’t result in the genetic diversity that a species needs to adapt to changing conditions in the environment. Sexual reproduction creates genetic diversity within a species, but it’s a slow way to reproduce. Our salp cousins have arrived at a strategy that combines the best of both reproductive methods.
When food is abundant, salps clone themselves extraordinarily fast. Their populations explode to take full advantage of the bounty; staggering numbers of salps gobble up vast blooms of algae. A single swarm of salp clones can cover hundreds, or even thousands, of square miles. And because of the constant gene shuffling that comes with the sexual reproduction of salps, when the environment changes, some individuals have the genetics necessary to deal with the shifting conditions.
We have explored less of the ocean floor than we have the surface of Mars. Think of the strange beings yet to be discovered in the seas of our planet. There is no end to the weirdness beneath the waves, and each creature stranded on the shore tells a story of survival and adaptation in the watery world where our own species began.
The salps that wash ashore reflect and refract light in a dazzling display. Each gelatinous tunic acts as a sort of prism and lens, magnifying sand and breaking white light into bright colors. Who needs drugs when salps are washing up on the beach bearing rainbows in their alien bodies.
Crabs scurry in and out of rocky crevices in tidepools, and along the sandy bottom beneath the surface of the waves. We invited guest author, filmmaker and photographer, Stephen Grace, to share his take on on intertidal crabs in Oregon.
By Stephen Grace – author, filmmaker and photographer
Lined Shore Crab
Crabs add drama to the intertidal zone. The lined shore crab (Pachygrapsus crassipes) skitters sideways, scooting over rocks and across sand as it searches for algae and small animals to eat. During the day this flat crab hides from predators by slipping into rock crevices. When forced to face a creature that wants to eat it, this scrappy little fighter—smaller than a silver dollar—rears up, extends its claws, and prepares to do battle with beings that tower above it. If a gull grabs one of the crab’s legs, the captured crustacean can escape by shedding its limb; the crab then grows a new leg.
Lined Shore Crab (Photo by Stephen Grace).
I often hear shore crabs clattering across rocks several feet above the water and see them hurrying over sand several yards from the nearest tidepool. The lined shore crab spends at least half its life out of the water. After venturing across dry terrain, it returns to the sea to dampen its gills, which stay moist in sealed chambers that store water—a useful adaptation for a creature that ventures beyond the ocean’s edge.
A marine creature transitioning into a terrestrial animal, the lined shore crab carries a bit of the sea in its gills as it crawls sideways across the alien shore that we now call home. We also carry some of the sea, our ancient home, within us—as salt in our blood and sweat and tears.
* * *
Mole Crab
Perhaps the least crablike of all intertidal crabs, the mole crab (Emerita analoga) has been described by beachgoers as everything from a little armadillo to a giant bug. This crab smaller than a thumb goes by many names: sea cicada, sand flea, sand fiddler, and sand crab. The tips of a mole crab’s legs are blunt paddles adapted for digging in sand, instead of the sharp pinchers of other crabs. Kids derive endless delight by digging up mole crabs with their bare hands and then watching the busy creatures rebury themselves. The sand-colored crabs melt into the shore in little more than a second, disappearing in liquefied sand, vanishing like a magic act.
Mole Crab (Photo by Stephen Grace).
Fattening on plankton and in turn feeding birds and fish, the mole crab is an important link in the food chain at the ocean’s edge. Gulls do the “seagull shuffle,” lifting their feet up and down at the edge of pools to loosen mole crabs from the sand. Surfperch lurk just offshore, gorging themselves on mole crabs tumbling through the waves.
Unusual for crabs, the mole crab can tread water and swim. Whether in the ocean or on the shore, the creature can move in only one direction—backwards—unlike most other crabs that scurry side to side.
With its ten legs tucked in toward its body, the mole crab is rolled like a little barrel by the surf. In the swash zone, where waves break on the shore, the mole crab burrows backward into the sand, hiding from predators and anchoring itself in place to feed. A buried crab faces seaward with the stalks of its eyes poking above the sand and a pair of breathing antennae extended to funnel water down toward the creature’s gills. When waves wash over the crab, it unfurls a pair of feeding antennae: long, feathery appendages that comb the water for plankton.
Female mole crabs are usually twice as large as males; sometimes several small males cling to a female that drags its suitors through the sand. After the crabs mate in spring and summer, the female produces eggs of vibrant orange. She keeps this brightly colored cargo stashed against her abdomen, brooding the eggs for a month until they hatch into larvae. The larvae drift as plankton, wandering the sea for two months or more until they settle on a distant shore, where the wet sand bubbles with their burrowing.
When mole crab populations explode, liquefied sand at the ocean’s edge seems to boil as countless numbers of the creatures bury themselves, racing to hide from the beaks of hungry birds, and hurrying to anchor themselves in place as the waves wash in, bringing a bounty of microscopic food.
Only the fast survive: the more quickly a mole crab burrows into the sand, the less likely it is to be eaten. Sluggish burrowers end up in the bellies of predators, and if the slow crabs that are eaten haven’t yet bred, their genes aren’t passed on to the next generation. In time, through many hundreds of generations, the overall burrowing speed of the species increases. But their predators also get faster. Fish and birds that manage to snatch mole crabs before the creatures disappear into the sand pass on the genes that make them swift, and an evolutionary arms race between predator and prey plays out at the ocean’s edge.
Our species, born of the natural world, retains the aggressive and competitive drives that allow individuals to survive. But we also cooperate in remarkable ways, including the collaborative enterprise of science. Researchers use the mole crab in neurological studies because the sensory neurons in the creature’s tail are the largest known of any animal.
* * *
Pacific rock crab
Unlike the mole crab that is friendly to human fingers, the Pacific rock crab (Cancer antennarius) and the red rock crab (Cancer productus) can punish the hands of tidepoolers who comb through seaweed.
Pacific Rock Crab (Photo by Stephen Grace).
Like many crab species, rock crabs are opportunistic and eat dead material along with a range of live animals: mussels, barnacles, snails, and other crabs. The robust claws of rock crabs crush barnacle shells. Unlike the cutting pinchers of Dungeness crabs that shred neoprene gloves and rip human skin, the pinchers of rock crabs crush. These powerful levers can crack a pencil in half (I tried this after reading about it). It’s even said that rock crabs can break a human finger. Though I have yet to meet someone with a broken digit who can confirm this, I keep the power of rock crab pinchers in mind while moving kelp and probing crevices in search of creatures.
When the tide is out, rock crabs burrow in sand near rocks and seaweed to hide from gulls. A rock crab’s bone-crushing power offers little protection from agile gulls that dodge a crab’s flailing pincers. When gulls find a stranded crab, they flip the creature onto its back and pierce its belly armor with quick jabs of their bills. And a crab that a few minutes earlier may have cracked open a snail shell to eat the living animal inside is now, in turn, devoured alive.
The sound of surf instills in human visitors a sense of peace. But life in the intertidal zone for the creatures that struggle to survive in this crowded, chaotic environment is anything but calm. Perhaps the poet Alfred Tennyson had red rock crabs in mind when he penned the phrase that has come to exemplify the eternal violence of the natural world: “Nature, red in tooth and claw.”
* * *
hermit crab
Finding the right shell can be a matter of life and death for hermit crabs (Pagurus sp.). Empty seashells provide hard houses for soft-bodied hermit crabs, which are forced to search for larger homes each time they outgrow a shell. The supply of suitable shells is limited, leading to a crowded and often violently competitive housing market. Hermit crabs grapple like wrestlers, grabbing each other’s shells with frantic claws as they tumble through the sand, trying to oust their competitor from its house.
Hermit Crab (Photo by Stephen Grace).
Though hermit crabs often battle each other for the best homes, they also display noteworthy forms of cooperation. Sometimes two crabs size each other up, probing and prodding each other’s shell, assessing its suitability by using their legs like calipers to measure its dimensions. But then, instead of fighting, they trade. This bloodless shell swap often benefits both parties.
Even more remarkable is hermit crab queuing behavior, which seems almost British in its politeness. When a home-hunting hermit crab comes across an abandoned shell that is too large, instead of continuing to search for the perfect shelter, the crab patiently waits by the oversized house. Other crabs soon show up. After inspecting the abandoned shell and finding it too large, the new arrivals check out each other’s shells and form an orderly line from largest crab to smallest. When a crab large enough to move into the empty shell finally arrives, the big crab’s vacated shell is snatched up by the next largest crab in line, whose vacated shell is used by the next crab in line, and so on. Hermit crab queues seem better organized than a group of humans trying to agree on a pizza order.
Some crab species also cooperate with anemones, placing these predators with their poisoned crown of tentacles on their shells for protection. In return, the anemones become more mobile than if they’re attached to rocks, and they dine on bits of food left over when their crab partners eat.
Combat often seems the rule in nature. Yet cooperation can also be an effective strategy in the battle to survive among crabs and all other creatures, including big-brained apes. The ability of our species to work together in human societies has grown from deep evolutionary roots in the animal kingdom.
Numerous strange creatures wash up on Oregon’s beaches – everything from jellyfish, to salps, to organisms that look like gelatinous pickles called pyrosomes. This month our guest author, Stephen Grace, shares with us about the strange creatures that wash up on Oregon’s beaches this time of year – Velella velella.
By Stephen Grace – author, filmmaker and photographer
In winter and spring, Oregon’s beaches can turn a vivid hue of purplish blue. Known as “By-the-Wind Sailor,” the Velella velella is a living blue boat at the mercy of the winds. (Velella is one rare instance of an animal’s scientific name being more fun to say than its common name). Storms blow these odd creatures with melodious names ashore, stranding them in uncountable numbers.
Velella-covered Beach (Photo by Stephen Grace)
Cousin to anemones, jellyfish, and the Portuguese man o’ war, velella is a carnivorous predator. Toxins in its tentacles are deadly to its plankton prey but don’t pack enough punch to poison humans. However, some people with sensitive skin report rashes after handling these stinging hydrozoans; touching your eyes or mouth after touching a velella is not recommended. Also not recommended is running, or even walking quickly, across a velella-covered beach, which becomes a slippery mess as the creatures decay. And the reek of rotting velella can ruin a beach picnic.
A by-the-wind sailor is not a single creature. Rather, it is a colonial organism: a collection of hydroid polyps that clone themselves, build a buoyant boat with a stiff triangular sail, and take on specialized functions of protection, feeding, and reproduction—similar to cooperating crew members of a ship who perform tasks of guarding the boat, catching fish, cooking meals, and so on. The individual polyps of a velella colony are linked together by a digestive canal through which they share food. Each velella is a busy world of specialized polyps borne on a tiny boat across the wind-stirred seas.
The sex life of this blue sailor is bizarre. Reproductive polyps of a colony make many tiny medusas—basically miniature jellyfish. Each medusa, after it leaves the colony and develops to sexual maturity, broadcasts into the water either eggs or sperm, which mix to create a larva that grows into a colony of hydroid polyps; then this new colony produces more medusas to continue the cycle.
A velella that washes ashore is sometimes gobbled by a hungry gull. In the open ocean, by-the-wind sailors are eaten by the ocean sunfish, a creature that can grow to more than 2,000 pounds. These behemoths rise toward the surface to sip velella, and colonial organisms a couple of inches long become the flesh of the largest bony fish on the planet. Velella is also preyed upon in the ocean by a species of purple snail that makes a bubble raft to stay afloat as it stalks its sailing prey. The by-the-wind sailor is also hunted by a sea slug known as the blue dragon.
When velella by the billions arrive in Oregon, covering vast stretches of beach in purple haze or painting the shores electric blue, I hunt for the legendary blue dragon nudibranch (Glaucus atlanticus). This gorgeous sea slug with fingerlike projections reminiscent of dragon wings uses a gas-filled sac in its stomach to float upside down. The blue side of its body faces upward, blending with the water to hide the creature from birds. The blue pigment is also thought to be a sunscreen that protects the blue dragon from the harsh UV rays that bombard the ocean’s surface; velella uses the same blue pigment to shield it from the sun. The slug’s silver side faces downward, merging with the silvery surface of the sea to conceal the creature from fish. This camouflage scheme is similar to the black-and-white color pattern of a penguin or a common murre that helps the birds avoid being eaten from above and below. But the blue dragon has a defense much more stunning than countershading.
This predatory sea slug attacks not only velella but also the Portuguese man o’ war. The blue dragon stores stinging cells from the tentacles of its poisonous prey, stealing deadly man o’ war missiles for use as its own protection. A carnivorous kleptomaniac, the blue dragon can deliver a powerful sting to animals that try to eat it—and to people who pick one up, thinking it’s just a pretty curiosity floating in the water or lying on the sand.
The blue dragon has been found in tropical and temperate oceans all over the word in association with velella. Though I’ve heard of neither a blue dragon nor a Portuguese man o’ war washing up on local shores, I’m keeping my eyes peeled. It’s unlikely either of these species will appear on my backyard beach, but not impossible.
I saw a dead longnose lancetfish in a driftline near my home a few weeks back. With a snaky body, spiky sailfin, and barracuda teeth, this four-foot-long denizen of the deep seemed like a mythical sea beast. A living loggerhead turtle was stranded on the same beach this past winter. A pelagic red crab species common to the coast of Mexico recently turned up in Oregon. This crustacean that resembles a little lobster is rarely seen north of San Francisco but washed up this spring as far north as Seaside. And a Pacific snake-eel from subtropical waters caused a stir in southern Oregon when three sinuous feet of snake-like body leading toward a fanged mouth appeared on a beach.
The Pacific Ocean covers half the planet, and anything could turn up along the coast—especially in times of exceptionally warm water, as in recent years, when creatures from tropical latitudes followed warm currents northward to Oregon’s chilly shores.
In collaboration with the Oregon Coast Aquarium we held our annual re-fresher training course for our volunteer scientific SCUBA divers. This year we will be conducting SCUBA surveys at the Cascade Head Marine Reserve.
We have selected our two local fishing vessels to help with this year’s hook-and-line surveys. The surveys will be conducted at Cape Perpetua and Cascade Head, in both the spring and fall months.
Our staff participated in four conferences over the last several months, giving us an opportunity to share some of our research and lessons learned with others. We took part in the Western Groundfish Conference, Ocean Sciences Conference, Oregon Chapter of American Fisheries Society Conference, and the Social Coast Forum.
Sea stars commonly dot rocky surfaces in and around Oregon’s marine reserves, although large ones have been less frequently seen over the past several years. We invited guest author, filmmaker and photographer, Stephen Grace, to share some of his photos and perspective on intertidal sea stars here in Oregon.
By Stephen Grace – author, filmmaker and photographer
A few years ago Oregon’s intertidal zone was stacked with starfish, their brilliant bodies splashing red, orange, and purple color across rock surfaces when the tide receded. Now, few tidepools are brightened by the starfish that survived a recent plague of sea star wasting syndrome, the largest observed die-off of marine animals in recorded history.
Ochre Sea Stars (Photo by Stephen Grace)
The ochre starfish (Pisaster ochraceus), popular among tidepoolers for its pretty colors, performs the role of predator in the intertidal zone. This carnivore uses suctioned tube feet powered by hydraulic pressure to pry open a mussel shell. The ochre starfish (or “sea star,” as scientists prefer) needs only to open a mussel shell a sliver. The sea star makes use of a slit less than a millimeter wide by thrusting its stomach out of its body and into the shell to slurp the mollusk’s soft flesh. Pretty this sea star may be, but peaceful it is not.
Scientists consider this slayer of mussels a keystone species, a top predator that plays a critical role in an ecosystem. When the ochre sea star disappears from the intertidal zone, the ecology of the ocean’s edge undergoes a dramatic shift—similar to an arch collapsing when the keystone that holds the structure together is removed. Without the ochre sea star keeping the population of its prey in check, mussels cover the intertidal zone, displacing other species and diminishing diversity.
This keystone species concept was demonstrated in a classic experiment in the 1960s. A clever scientist removed all ochre sea stars in a study plot and observed the consequent downward creep of mussel beds. Mussels are limited in how low they can go on rocky surfaces not by ocean conditions but by sea star predation. Put another way, the bottom edge of a mussel bed is the upper limit of the ochre sea star’s hunting range. This sea star species has evolved to withstand being out of the water for up to eight hours at a time. But if this marine creature climbs too high in order to hunt mussels, it is exposed to air beyond what it can tolerate, and it desiccates and dies.
The ocean is vast. But rocky real estate at the water’s edge is relatively rare, creating fierce competition for space. Almost every hard surface is crammed full of creatures that need to attach somewhere solid. In healthy tidelands, mussel beds dominate the upper zone where sea stars can’t survive. But mussels cannot cover the lower regions of rocky terrain in the sea star’s hunting zone, leaving habitat available for other species. When sea stars were removed from the experimental plot, mussels cornered all the housing options, sending other creatures packing.
Sea Star Tube Feet (Photo by Stephen Grace)
In the absence of the tidepools’ top predator, mussels modify the entire habitat of the rocky intertidal zone. This ecosystem engineering benefits some creatures that thrive in the layered spaces of mussel mazes. But when mussel beds monopolize rocky real estate, little room is left for other organisms that need to anchor themselves directly to blank surfaces, leaving seaweeds, sponges, and anemones homeless.
Similarly, when wolves were extirpated from Rocky Mountain National Park in a misguided effort to slaughter top predators, elk herds flourished unchecked. This led to ecological mayhem as elk devoured aspen forests and willow communities, creating a cascade of consequences that altered the region’s ecology. Tidepoolers often assume sea stars are docile plankton eaters. But the ochre sea star is like a wolf that prowls the ocean’s edge, a tiger of the tidepools.
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Beginning in 2013, the entire Pacific Coast between Alaska and Mexico seemed the subject of a bizarre experiment, as though a mad scientist had flipped a switch that made sea stars vanish. The sudden absence of the ochre sea star startled beachgoers and spurred scientists to study the causes and consequences of sea star wasting syndrome. Researchers found that many other species were vanishing along with the ochre sea star, including one of the world’s largest and fastest sea star species.
The sunflower sea star (Pycnopodia helianthoides) is an Olympic sprinter of intertidal creatures. This animal that grows up to a meter long can move a meter a minute. In two years of stalking the ocean’s edge along Oregon’s North Coast I have yet to see a sunflower star. These speedy beasts with twenty to thirty arms passed into legend as they vanished from the intertidal zone. Only tales told by tidepoolers remain: accounts of prey species like urchins and snails fleeing for their lives as this storied super-predator prowled the pools, racing to capture creatures with its suctioned tube feet.
Sunflower sea stars prey on urchins, which feed on kelp. The great kelp forests of our planet teem with life that rivals tropical rainforests in diversity and productivity. Urchins, their numbers unchecked by their vanished sea star predators, have decimated kelp—much like the elk browsing willows down to bare streambanks in the absence of wolves. Rich forests of kelp along the Pacific Coast have been replaced by urchin barrens. These denuded plains no longer nurture myriad creatures, including juvenile fish of commercial importance. The influence of sea star wasting syndrome can be felt as far away as coastal communities that rely on healthy fisheries, illustrating a core principle of ecology: everything is connected.
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So what caused this ocean plague of staggering scope? Sea star wasting syndrome is a complicated puzzle. A virus is associated with the syndrome, but the virus has been found in preserved sea star specimens seventy years old. Why the virus is suddenly causing such widespread mortality is a question that continues to challenge scientists. There have been plagues of wasting disease in past decades, but never has an outbreak occurred over such a broad geographic area or annihilated such vast numbers of sea stars.
Research has revealed a link between high ocean temperatures and increased virulence of wasting syndrome. Beginning in late 2013 and persisting into 2016, a mass of unusually warm water along the West Coast dubbed “the blob” adversely affected many forms of marine life. A leading hypothesis is that the high ocean temperatures of the past few years stressed the sea stars, making the creatures more vulnerable to the viral pathogen, and leading to the unprecedented wave of sea star death that recently swept the Pacific Coast.
Sea stars are known for their ability to regrow severed arms. So potent is their regenerative power, when they lose all their arms but one, the lone limb can sometimes grow into a whole new sea star. Stories tell of fishermen who hated starfish that preyed on crabs in their traps; the fishermen sliced the predators in half and threw them back into the sea. As in a fable, one crab-eating starfish became two. Rising ocean temperatures, however, could be the end of the story for sea stars.
The good news is that tremendous numbers of juvenile ochre sea stars have recently been seen in the intertidal zone. Now the size of a quarter or dime, these silvery creatures secreted away in cracks and crevices of rocks will perhaps escape the fate of their ancestors and once again paint the intertidal zone with striking color as they mature. Or maybe as these creatures age they will succumb to the syndrome, developing lesions, contorting their limbs, and melting into mush as they follow the fate of the wasted generation before them.
Scientists have identified a gene some sea stars have that makes them resistant to wasting syndrome. Scientists have also determined that adult sea stars succumb more readily to the syndrome than juveniles do. Pieces of research are snapping into place, but the overall puzzle of the syndrome remains to be solved.
No one knows for certain if large populations of healthy adult sea stars will return to the Pacific Coast, and the changing intertidal zone in their absence is an ongoing area of study. As a citizen scientist, I join other concerned citizens in following established scientific protocol to collect sea star data for scientists. Researchers use this data as they continue to investigate what caused this vast upheaval in ecology at the ocean’s edge.
