Category: Marine biology

Six months, and a big return

Posted on by Allison J. Gong

Next week I will be six months beyond a total replacement of my right knee. The rehab has been long and tough, and I’m nowhere near the end yet. I’ve been told by my surgeon to expect a 12- to 18-month recovery to get back to whatever my new normal will be. By that estimate I’m either 1/3 or 1/2 of the way there; given the way things are going I suspect it’s the smaller fraction, so I’m looking at another year of ongoing, slow improvement.

I’ve finally gotten strong enough that I felt ready to return to the intertidal. And yesterday being the first day of a new year, it seemed fitting to venture out into my old life again. I chose a site that didn’t involve any cliff-climbing (not quite up to that yet), but did have stairs so I could challenge the knee. Down is still hard, but up is a piece of cake now.

Two people standing among dark rocks. Person in the front is wearing a bright pink jacket and holding a green rectangular object. Person in the midground is wearing a black jacket and green knee-high boots. There is a lighthouse in the background.
My friend, Sara, and me on the rocks at Whaler’s Cove
2026-01-01
© Alex Johnson

It was great getting out to the intertidal and seeing some of my old friends again! January isn’t the best month to find happy algae, but the rockweeds were already recruiting and growing. Here’s a baby rockweed, probably Pelvetiopsis limitata (they can be hard to ID as youngsters):

Olive-green ribbon-like structure with bifurcated tips emerging from wiry dark red threads
Baby rockweed, probably Pelvetiopsis limitata, in a thicket of Endocladia muricata
2026-01-01
© Allison J. Gong

And there were some lovely stands of Fucus:

Bunches of flattened dichotomously branching algae, olive-green in color, on rocks
Thalli of the rockweed Fucus distichus
2026-01-01
©️ Allison J. Gong

Note that the tips of the Fucus branches are flattened. These are young thalli. In the summer, mature thalli will have swollen tips full of gametes. Fucus, and the rockweeds in general, have what we call an “animal-like” life cycle instead of the alternation of generations that is more typical of seaweeds. And we won’t even get into the complexity of the alternation of three generations in some of the reds! So yes, Fucus thalli come in male and female forms that produce sperm and eggs, respectively. Sounds familiar, doesn’t it?

We saw several ochre stars, none of which were ochre in color. And now that I think about it, I see many more P. ochraceus that are purple, red, or orange than are ochre.

Dark purple star-shaped animal attached to a rock
Ochre star (Pisaster ochraceus)
2026-01-01
© Allison J. Gong
Bright orange star-shaped animal stuck to a rock
Ochre star (Pisaster ochraceus)
2026-01-01
© Allison J. Gong

And lest we forget, Sea Star Wasting Syndrome (SSWS) hasn’t been banished from the world. I suspect it will always be around but won’t always be as prominent as it was 10 years ago. Yesterday we saw two disembodied arms of a purple Pisaster ochraceus. The rest of the body was nowhere to be found, and I guess this star dismembered itself a couple of days ago.

Two approximately triangular structures on a sandy background with two large rocks and a snail shell
Disembodied arms of Pisaster ochraceus in a tidepool
2026-01-01
© Allison J. Gong

On a much more pleasant topic, I noticed a pattern of different organisms lined up in rows.

Row 1: Limpet scars. These ovoid blotches are the scars made by a limpet, Discurria (formerly Lottia) insessa. The limpet lives on the stipe of feather boa kelp (Egregia menziesii), shown below. It eats the algal film that accumulates on the kelp but eventually ends up chewing through the stipe, which then breaks. They literally eat themselves out of house and home, poor guys.

Long brown strap running horizontally across the image. There are eight golden ovals along the length of the strap.
Limpet scars on stipe of Egregia menziesii
2026-01-01
© Allison J. Gong

Row 2: Anemones. Many intertidal animals (and algae, for that matter) settle preferentially in cracks and crevices. These are the places that hold water the longest at low tide, giving the organisms a slight bit of protection against desiccation. For the same reason many organisms prefer to settle on vertical rather than horizontal surfaces. I found this group of anemones in an almost-straight line in a shallow indentation in the rock.

Five roughly circular objects arranged approximately vertically against a pink background
Row of anemones (Anthopleura spp.)
2026-01-01
© Allison J. Gong

Row 3: Anemones. In geometry, two points define a line. So I can claim that these two anemones make a row! You may have to look carefully to see the second anemone.

Circular object with white protruding tentacles radiating from center. To the right, a similar object with transparent tentacles.
Moonglow anemones (Anthopleura artemisia)
2026-01-01
© Allison J. Gong

These are the same species. Anthopleura artemisia is highly variable, more so than the other species in the genus. The tentacles can be a solid opaque color, as in the animal on the left, or transparent/translucent with or without opaque patches, as in the anemone on the right. They tend to live in sandy areas and often have sand covering the oral disc. If disturbed they will retract into the sand and disappear.

Beach landscape. Large boulders covered with brown/reddish algae or green plant growth, on sandy bottom. Gray cloudy sky above greenish water.
Scenery at Whaler’s Cove
2026-01-01
© Allison J. Gong

All in all it was a fantastic re-entry into the rocky intertidal. My body remembered how to move around, my balance was not entirely shot to hell, and my knee did fine. I was able to forget about it and just use it like a normal person would. When I started physical therapy I told the therapists that one of the things I need to be able to do was work in the rocky intertidal. They were skeptical at first, because they envisioned me jumping from slippery rock to slippery rock. I had to explain that I’m very safety conscious in the field and know all the tricks of an old-timer: Keep your body low (so you have less distance to fall) and keep three of the five points of contact (two hands, two feet, and one butt) with the rock at all times.

I’m calling this a major milestone achieved, even if I still have a long way to go. Yippee!

Collateral damage

Posted on by Allison J. Gong

My home town of Santa Cruz made national news the other day, 23 December 2024, when a series of massive swells caused part of the Municipal Wharf to collapse into the ocean. People in the restaurants and other businesses had to evacuate immediately, and three people were dropped into the water of Monterey Bay (they were all rescued safely and no human lives were lost). The bathroom building fell into the water and washed up on the beach at the mouth of the San Lorenzo River. Almost immediately, memes appeared, advertising a 2-bathroom unit with both river and ocean views, renting for $6000/month. Given the exorbitant rents here, you could argue that maybe this is a pretty good deal.

That afternoon, the same swell tore through the Santa Cruz Small Craft Harbor and replicated the damage done by the Fukushima tsunami in March 2011. The damaged docks had been replaced in 2014, but this recent damage ripped them up again. Boats and docks were thrown around and crashed into each other. An unknown amount of diesel fuel and gasoline were also “liberated” into the water.

My friend Murray has a little boat, Scherzo, that lives in the upper harbor on G dock. On the day of the worst swell, Murray had gone down to see how Scherzo was faring. At that point she had taken at least some cosmetic damage to her paint but didn’t seem to be taking on any water except rain water. The harbor patrol had closed all of the docks so he couldn’t get close enough to see if there were worse injuries. At one point another boat had come down the channel and gotten wedged under Scherzo so she was floating on top of it. Somebody rescued Scherzo and tied her up at a spot just under the ramp from her usual berth. Yesterday, Christmas Day, Murray called us to say that he was down at the boat and asked if Alex (my husband) could help him get her out of the water, as more big swells were forecast. I’m not very useful when it comes to boats, but I went along to watch things from above and hold lines and such.

Before they could take Scherzo out of the water, they had to make sure she was seaworthy enough to be driven down to the boat ramp at the lower harbor.

Dock with two large boats tied up on one side and one small boat tied up on the other side. One person in the small boat. One person crouching on the dock next to the small boat
Murray and Alex give Scherzo a check-up
2024-12-25
© Allison J. Gong

Behind Murray, who is wearing the pink cap, you can see damage to the finger dock. And notice that the big boats aren’t sitting straight in their slips. Scherzo‘s usual spot is on the other side of the ramp; she got pushed under the ramp and a kind soul tied her up here.

This is the capsized boat that had gotten wedged under Scherzo. It was now stuck under the ramp, just in front of Scherzo‘s spot.

Capsized boat wedged under a pedestrian bridge
Capsized boat under ramp
2024-12-25
© Allison J. Gong

Scherzo‘s engine started right up, and the boat itself having been deemed safe to drive by Alex the Engineer, Murray took her down the harbor slowly. Alex and I met him at the boat ramp.

While we were waiting, we noticed that some of the pilings from the busted-up Wharf, which is more correctly a pier rather than a wharf, had been hauled out of the water and set in the parking lot.

Wharf pilings in the harbor parking lot
2024-12-25
© Allison J. Gong

Knowing that the biota on the pilings would be very similar to the critters I see in the rocky intertidal, I had to investigate. And it was very sad. Most of the animals had died waiting for a high tide that wouldn’t return. Some of the barnacles were still alive, albeit just barely so.

Log lying on pavement, covered with small pink blobs and large brown objects also covered with small pink blobs.
Large barnacles (Balanus nubilus) and pink corallimorpharians (Corynactis californica)
2024-12-25
© Allison J. Gong

Here’s a close-up shot of one of the big barnacles encrusted with other animals:

Beige pyramid-shaped structure with pink blobs on the lower surfaces
Large barnacle (Balanus nubilus) and pink corallimorpharians (Corynactis californica)
2024-12-25
© Allison J. Gong

There were many empty worm tubes, former homes of the beautiful Eudistylia polymorpha. I saw one dead worm that had fallen out of its tube:

De-tubed feather duster worm, Eudistylia polymorpha
2024-12-25
© Allison J. Gong

One of the rocky intertidal denizens, the pink barnacle Tetraclita rubescens, was there, too:

Pink barnacle (Tetraclita rubescens) with smaller barnacles (Balanus glandula) and mussel byssal threads
2024-12-25
© Allison J. Gong

To get a feel for how big Balanus nubilus and Tetraclita rubescens are, my left index fingernail measures exactly 10 mm across. That B. nubilus is a big sucker!

Large volcano-shaped structure with two smaller pink volcano-shaped structures on the side. Finger for size reference
Balanus nubilus and Tetraclita rubescens
2024-12-25
© Allison J. Gong

Balanus nubilus is a strictly subtidal species that I never see in the intertidal. Tetraclita rubescens occurs in both the intertidal and the subtidal; some of these subtidal specimens were larger than the ones I see in the intertidal. Most sessile marine invertebrates can feed only when they are covered by water, which means that the ones living in the intertidal don’t feed at low tide. Thus the subtidal T. rubescens can get larger than their intertidal conspecifics, simply because they can feed 24/7. We see the same pattern with mussels in the intertidal: those higher up in the mussels’ range are smaller than the ones in the lower part of the range.

Some of the barnacles were still alive. They can close up their shells and wait out a low tide. But sitting out of the water for longer than a day was more than even they could withstand.

Other old friends were there, including many sea anemones. This is the sunburst anemone, Anthopleura sola, looking the way it does when I see it in the intertidal at low tide.

Cylindrical animal hanging down from vertical surface
Sunburst anemone (Anthopleura sola)
2024-12-25
© Allison J. Gong

Other anemones had been caught in the act of dividing. These would be the cloning anemones, Anthopleura elegantissima.


2024-12-25
© Allison J. Gong

2024-12-25
© Allison J. Gong

Probably the saddest thing was a desiccated red octopus on the pavement. It had probably plopped out of a nook and tried to make its way back to water. Poor little thing.

Grayish-brown lump with suckered arms
Red octopus (Octopus rubescens)
2024-12-25
© Allison J. Gong

The organisms on these pilings were caught in their final moments of life, just as the citizens of Pompeii and Herculaneum were when Mt. Vesuvius erupted in 79 AD. Some of them had tried to escape (the octopus) and some were not quite dead yet (the barnacles), but the inevitable is well, inevitable. At some point the pilings will be removed to the landfill. The same thing happened when the harbor docks were replaced in 2014. I happened to be there with a class and we saw all of the old docks piled up in the parking lot, with all of the attached biota slowly drying up in the sun.

So while there will be reports in the coming days about how many millions of dollars it will take to rebuild the harbor (again) and the pier, let’s not forget that there were other losses that cannot be assigned a dollar value. There is also a potentially major ecological impact of new (again) harbor docks. When the old docks were removed in 2014, they had been covered with a decades-old fouling community. The new docks were pristine new habitat for recruits, and shortly after they were put in I noticed an invasive brown alga, Undaria pinnatifida, which I hadn’t seen before. Undaria is a western North Pacific edible seaweed that is known culinarily as wakame. In recent years it has become one of the most abundant macroalgae in the lower areas of the harbor. The docks that were destroyed this week had been in place for only 10 years or so, and it will be interesting to see how primary succession occurs when new docks are installed. Hmm, that sounds like something I can have my Ecology students document and monitor!

I saw the light!

Posted on by Allison J. Gong

Last month I spent four days in the town of Egmont, BC. My husband and I had joined a friend on his annual excursion to the stomping grounds of his youth. We trailered the friend’s boat, Scherzo, up through Oregon and Washington and into British Columbia. We took a ferry and then ditched the car in Sechelt, piled our belongings and food into Scherzo, and headed up the Sechelt Inlet to arrive in Egmont. Incidentally, Egmont is entirely reachable by road, but it was kind of cool showing up in a little boat to the dock of the house we had rented.

Flat body of water with mountains and clouds in background. Small boat moored at dock in lower right corner.
View from our rented house in Egmont, BC. Scherzo is the little boat moored at the dock.
© Allison J. Gong
2024-08-15

On our way up Sechelt Inlet I had noticed quite a bit of brown scum on the surface of the water. I couldn’t collect any on my hands and it didn’t have a detectable odor, but some of my cerebral neurons did their job and the name Noctiluca came into my head. Noctiluca scintillans is a bioluminescent dinoflagellate. It is a regular component of the plankton in Monterey Bay at this time of year. What makes it distinct from other dinoflagellates are its large size (can be greater than 1mm in diameter) and the fact that its hydrophobic theca (cell wall) causes cells to get stuck at the surface of the water. They can look like tiny bubbles floating at the surface.

There wasn’t as much Noctiluca at our dock in Egmont as we’d seen on our way up the inlet, but it was worth going out at night just to see. Dinoflagellates and other bioluminescent critters light up when disturbed. We borrowed Scherzo‘s oar to disturb the water and see what happened. We could see light when Alex drew the oar back and forth in the water, but a washing machine-like agitation was the best for getting the cells to flash.

Bioluminescence is one of those phenomena that never gets tiring. In this case, each Noctiluca cell emits one tiny flash of light when it gets bumped. These photos give you an idea of how dense the population was. Dinoflagellates tend to be late-season bloomers, becoming more abundant than the diatoms that dominate the spring and early summer phytoplankton. Many dinoflagellates, despite being considered part of the phytoplankton, are heterotrophic either in addition to or instead of being autotrophic (photosynthetic). Noctiluca is one of the heterotrophic dinoflagellates. It preys on smaller cells, including diatoms, small invertebrate larvae, and fish eggs.

If I had been at home with my lab supplies at hand I would have collected some of the cells in a scintillation vial, brought them into a dark room in the house, and shaken them up to observe the bioluminescence under controlled conditions. As it was, seeing it in the field, so to speak, was really cool.

The Flyer comes home

Posted on by Allison J. Gong

Last weekend the fabled Western Flyer came home to Monterey for a brief visit. For anyone who doesn’t recognize the name, the Western Flyer is the boat that Ed Ricketts and John Steinbeck took to the Sea of Cortez in 1940. At the time of the trip she was just another purse seiner in Monterey, and after the collapse of the sardine fishery she passed through several owners’ hands and was outfitted first as a deep water trawler and then as a crab boat. Several decades passed, and in 2012 the boat, now named the Gemini, sank near Anacortes, WA. She was refloated and sank again in early 2013. This time she was left on the bottom for several months. In June 2013 she was refloated again and taken to dry dock in Port Townsend, WA, where she sat for a couple of years until she was purchased and the long journey towards restoration began. The Western Flyer Foundation has more about the acquisition, restoration, and new purpose of this boat.

Fast forward to 2023, and it was time for the Western Flyer (somewhere along the way she was rechristened to her original name) to return to California. The majority of the work to restore her (woodwork, mechanical engine stuff, etc.) was done up in Washington, which was fitting because she was originally built in Tacoma. She had to come down to California, however, to be kitted out to do science. And she will live here and work out of Monterey.

On Saturday 4 November 2023, the public was invited to welcome the Western Flyer to Monterey. It was a big event, with a boat parade, a decorated boat contest, and much speechifying. The plan was for boats to gather outside the Monterey harbor and wait until the Flyer arrived from Moss Landing with her escort, wait until she was berthed in her temporary spot in the marina, and then parade past her and wherever the judges were. I never did quite figure out where that was. We trailered our friend Murray’s boat, Scherzo, down to Monterey to see the Flyer and tootle along in the boat parade. Scherzo has her own stories to tell, as she was built in Murray’s backyard over a period of several years. Murray was unable to join us, so it was just Alex and me in the boat parade aboard Scherzo.

Man and woman in a boat on the water

It was hard to count the boats out on the bay waiting for the Flyer, but there were about 40. We were in the middle of the pack. Most of the boats were sailboats but there were a few motorboats and one research vessel along for the ride. Scherzo was definitely the only little boat!

Sailboats in the water, with mountains in the background
Boats waiting outside the Monterey harbor for the Western Flyer
2023-11-04
© Allison J. Gong

Given our position in the middle of the boat scrum, we didn’t get a very good view of the Flyer when she arrived. But once she got into the harbor, the fireboat escort made it easier to see where she was.

Sailboats outside harbor. Fireboat in background spouting water into the air.
Western Flyer‘s fireboat escort in Monterey harbor
2023-11-04
© Allison J. Gong

We were instructed to wait outside the harbor until the Flyer was docked, and then position ourselves into single queue. Being quite ignorant about how these things are done, I imagined that getting ~40 vessels of various sizes and propulsion systems, all bobbing around in Monterey Bay, into a single-file line would be like herding cats, but it was very well organized. Clearly these boat captains know what they’re doing.

And how was I doing with my infamous seasickness, you ask? I was hopped up on Dramamine, the only drug that works for me. And I was fine while on the water. After that, though, the sleepiness took hold and I had to take a nap on a park bench.

Sailboats in water, with a city and mountains in the background
Boats waiting for the parade to begin
2023-11-04
© Allison J. Gong

The Flyer was docked at about noon, and the speechifying began. Tours of the boat would start at 13:00 and end at 16:00. We left to get some lunch, hoping to beat the crowd, and came back at around 14:00 to find that there were still hordes of people waiting to go aboard. So we took Scherzo out for another tootle, first cruising around the harbor to get some nice shots of the Flyer.

Western Flyer, docked in Monterey
Western Flyer, docked in Monterey

We still had time to kill, so we left the harbor and went down the coast as far as the Monterey Bay Aquarium, stopping to look at sea otters and murres. Then we looked at the time and saw that it was about 15:30, so we turned around and high-tailed it back to the harbor. We got Scherzo out of the water and ran over to the Flyer. By my watch it was 15:58, so I convinced the volunteer to let us get in line.

Sign reading "Western Flyer, the original boat from Sea of Cortez by John Steinbeck and Ed Ricketts"

Even at the end of the public access period, it took about 45 minutes for us to get onto the boat. Once aboard, we could wander around and take pictures of pretty much everything. My eye, as usual, was drawn to the less obvious things.

This gentleman wearing the colors of the Italian flag, was explaining how purse seiners work. This display was on the rear deck, directly above what was originally the fish hold.

2023-11-04
© Allison J. Gong

We were not allowed to go below decks into the fish hold, because that’s the part of the boat that isn’t finished yet. The aft section of the hold will be the science lab and will eventually be kitted out with microscopes and a small library. I imagine there will be computers, too.

Wooden staircase leading down to a partially finished wooden floor
View into the unfinished science lab of the Western Flyer
2023-11-04
© Allison J. Gong

One of my favorite bits of the boat was this wooden turtle inlaid on the aft deck. It wasn’t until we got home that I remembered this passage from Sea of Cortez:

They hung the turtle to a stay where it waved its flippers helplessly and stretched its old wrinkled neck and gnashed its parrot beak. The small dark eyes had a quizzical pained look and a quantity of blood emerged from the pierced shell. . . . And now a strange and terrible bit of knowledge came to Tiny; turtles are very hard to kill. Cutting off the head seems to have little immediate effect. This turtle was as lively as it had been, and a large quantity of very red blood poured from the trunk of the neck. The flippers waived frantically and there was none of the constricting motion of a decapitated animal.

Steinbeck, John, and Edward Flanders Ricketts. Sea of Cortez, The Viking Press, New York, 1941.

I didn’t think at the time to ask, but I bet this inlaid turtle marks the spot where the hawksbill turtle came to its unfortunate end.

Inside the cabin we could see just how crowded things were, for a total of seven people on a 6-week expedition. There were three pairs of narrow bunks for scientists and crew, and a separate room for the captain behind the wheelhouse. There would be no privacy.

Wood framing two bunk beds. Round windows in the wall
Bunk beds aboard the Western Flyer
2023-11-04
© Allison J. Gong

The galley, on the other hand, felt rather spacious. The modern Western Flyer has a nifty modern fridge unit and seems well arranged to maximize usable space. The coolest part was the stove, which is the same model (although not the same exact unit) as in the original Flyer. It runs on diesel fuel and would have done a great job of heating the cabin area.

Old-fashioned stove with white ceramic doors
Stove on the Western Flyer
2023-11-04
© Allison J. Gong

The near future

The Western Flyer was in Monterey for another day (Sunday), so visitors could come and take pictures of her, but no additional tours were allowed. Then on Monday she went back up to Moss Landing. She will be there for about six months, for the installation of the science lab. After that, the Western Flyer goes back to school. She will take students on cruises, to study oceanography and marine biology, combined with the arts and humanities, with the goal of fostering curiosity about the natural world. The Western Flyer Foundation offers these educational programs free of charge. If you would like to contribute to this endeavor, please consider donating to the Western Flyer Foundation.

A celebration of worms

Posted on by Allison J. Gong

Yesterday, 30 June 2023, was deemed by the National Museum of Natural History to be International Polychaete Day, and the Smithsonian had an entire day of talks and activities for visitors to learn about the marine segmented worms. And you know me: I’m in favor of any event that draws attention to the animals that are not like us. So this is my own little celebration of worms I encountered over this past week.

Living with sea stars

I’ve written before about how many of the bat stars (Patiria miniata) I see at Pigeon Point carry small commensal polychaetes on their oral surface, often associated with the ambulacral groove. Several taxa of echinoderms are known to have associations with polychaetes, and I’ve seen worms crawling around on sea stars, sea urchins, and sea cucumbers. Oxydromus pugettensis is the polychaete I’ve seen on the bat stars in the field.

5-armed cream colored star-shaped animal being held in a human hand; two small brown worms on animal's surface
Commensal polychaete worms (Oxydromus pugettensis) on oral surface of bat star (Patiria miniata) at Pigeon Point
2018-06-01
© Allison J. Gong

Years ago now, I collected some bat stars to bring back to the lab. Some of them had worms, and I was interested in seeing how long the worms stuck around once the stars were in captivity. The answer was “Not very long.” I seem to remember that the stars had lost their worms within a week. And since then, despite having many bat stars come through my hands at the lab, none of them have acquired worms.

Until now. This past week I was moving stars around and cleaning tables after flushing seawater pipes. I have a large bat star and a smaller one running feral in one of the tables. I picked up the larger star and turned it over just to check on it, and saw a dark squiggly thing. It was a worm!

Hand holding a 5-pointed star shaped animal, mottled orange and brown in color
Aboral surface of bat star (Patiria miniata)
2023-06-26
© Allison J. Gong
Hand holding a 5-pointed star-shaped animal, cream in color
Oral surface of bat star (Patiria miniata)
2023-06-26
© Allison J. Gong

Can you see the dark squiggle on the oral surface?

Here’s a close-up of the worm:

Cream-colored scales surrounding groove containing flat-topped clear tubes. Small dark brown worm tucked into side of groove.
Oxydromus pugettensis in ambulacral groove of Patiria miniata
2023-06-26
© Allison J. Gong

This is the first time I have ever seen a sea star acquire a commensal worm. It’s gotta happen, because we see worms on stars in nature. But I do wonder about this relationship. The worms are highly mobile and probably leave one star and join another quite frequently, or remain free-living (i.e., not on a host star). I had brought in some algae the previous week, and it’s quite possible that the worm came along as bycatch and found its way to the bat star. I checked on the star later in the week, and did not see the worm. It hadn’t joined the smaller of the bat stars, either.

Baby worms

This past Monday I did a plankton tow off the end of the Santa Cruz Municipal Wharf. This was my first plankton tow of the year, and I wanted to see what was there. The water was very clear and the phytoplankton were lacking, but there was a decent diversity within the zooplankton. Of particular interest to this report were the baby worms.

Baby worms are present in any plankton tow collected at any time of the year, although they may be more abundant at some times compared to others. Clearly there isn’t much seasonality to reproduction in some of our local polychaetes. The most commonly seen baby worms in plankton samples are the metatrochophores of worms in the family Spionidae.

Adult spionids are benthic and live in tubes. They have two long palps that extend from the anterior end and are typically used to scrape up organic deposits from the area surrounding the tube. Like most polychaetes, spionids are broadcast spawners that cast gametes out into the water, where fertilization and development occur. Polychaetes go through a larval phase called a trochophore, defined by a ring of cilia (the prototroch) that produces the feeding current for the animal. Incidentally, many molluscs also go through a trochophore stage, but that’s a story for another time. Some polychaetes, including the spionids, have a second planktonic stage called a metatrochophore. The metatrochophore is a much larger and more elaborate version of the trochophore, with eyespots and few to many segments complete with associated bristles. They can crawl as well as swim. Some of them can be 3 mm long, which is pretty big for something that is still up in the plankton. The spionid metatrochophore also has the two long palps, which sometimes remind me of the flaps on Elmer Fudd’s hat.

These are photos of the same individual worm. It’s about 2 mm long, a little longer if all stretched out.

Tan colored, segmented object curled into a loose circle. One end is pointed and bears two ear-like flaps that extend backwards.
Metatrochophore of spionid polychaete
2023-06-26
© Allison J. Gong
Tan colored, segmented object, approximately bullet-shaped. One end is blunt, the other tapers to a rounded point. Tentacle-like structures extend along the sides of the body.
Metatrochophore of spionid polychaete
2023-06-26
© Allison J. Gong

There was another type of polychaete metatrochophore in the sample, but I don’t recognize which family this one comes from. I should, because I see it frequently enough to know it isn’t unusual. It might be a young phyllodocid metatrochophore, but that’s just a guess. Anyhow, this creature has fewer segments than the spionid metatrochophore and lacks the spionid’s long palps. It does have eyespots, segments with bristles, and (I think) two pairs of tentacles associated with the head region. This individual also contains a lot of oil droplets, visible as those small dark circles in the dorsal half of the body behind the head. Oil droplets serve as energy stores and flotation devices. Many marine invertebrate larvae stockpile calories as they feed and store them in oil. In some cases, these calories are needed to sustain a later larval stage that doesn’t feed.

Polychaete metatrochophore
2023-06-26
© Allison J. Gong

There you have it, my belated contribution to International Polychaete Day 2023. I always enjoy finding worms in our plankton. They have a lot of personality, and it’s fun to watch them zooming around. They are really fast swimmers, and I have to squash them under a coverslip—just a little—to get them to hold still long enough to take photos. Always worth the effort, though!

Exception to the rule

Posted on by Allison J. Gong

Ask any marine biology student to list some interesting factoids about barnacles, and one of them should be “Barnacles are benthic and sessile” by which they mean that barnacles live their entire lives glued to a single spot. This definitely describes what it means to be benthic. Barnacles are indeed stuck, for better or worse, to the location that their cyprid larva selected. Once the cyprid glues its head to the rock or other hard substrate, that’s it. A bad choice could mean that the barnacle starves, desiccates, or is unable to mate. A good choice means an opportunity to live long and prosper.

How is it, then, that we have things that are called pelagic barnacles? These are barnacles that live permanently attached to objects that move through the water. The objects can be living (e.g., whales or turtles) or non-living (e.g., boats). Pelagic barnacles are not just traveling versions of the species we see in the intertidal or on docks and pilings—they are different species altogether.

Yesterday morning I went to Younger Lagoon to see what had happened during the most recent storm. The lagoon had once again breached through to the ocean, and bits of Monterey Bay were sloshing into the lagoon. None of that was unexpected.

What did catch my eye were the fuzzy blotches on some of the pieces of wood that had washed up onto the beach.

Small log festooned with interesting objects
2023-03-10
© Allison J. Gong

A closer look confirmed my thought that these were pelagic barnacles in the genus Lepas. These are a type of gooseneck barnacle, similar in overall morphology to the very common intertidal Pollicpes polymerus.

Pelagic barnacles (Lepas sp.) on piece of wood
2023-03-10
© Allison J. Gong
Lepas sp. on piece of wood
2023-03-10
© Allison J. Gong

These barnacles were small, and having been emersed for at least several hours were definitely not looking their best. They didn’t smell dead just yet, but since they had zero chance of getting back into the water before the next high tide, were doomed. A few of them had their cirri—the modified thoracic appendages that barnacles sweep through the water when feeding—extended, which I’ve seen before with barnacles on their last leg. See what I did there? I did touch some of the cirri, and the barnacles did not respond at all, although they had not yet dried out to the point of crispiness.

Lepas makes a living attached to objects that float in the ocean. I usually see them on logs or smaller pieces of wood, as they are here, but do occasionally find tiny ones on the blades of giant kelp (Macrocystis pyrifera). Living attached to objects that float with the currents means the barnacles are constantly moving through the water, able to feed 24/7 without the constraints of high and low tide. Compared to the robust gooseneck and acorn barnacles of the rocky intertidal, Lepas is translucent and delicate, with plates that are only weakly calcified. Given its lifestyle, Lepas rarely has to withstand bashing surf or waves; by the time it does, its substrate is inevitably headed onto shore, where the barnacles will die anyway.

So there you have it—a barnacle that flouts the rule and manages to be both benthic and pelagic. Or perhaps I should say that it is benthic but has a pelagic lifestyle. Either way, Lepas is making the best of both worlds, isn’t it?

Rock stars

Posted on by Allison J. Gong

Some organisms, like some people, have a charisma that just can’t be explained. For me, the sea palm (Postelsia palmiformis) has always been one such organism. Maybe part of its charm is the fact that it’s not very common; it lives on rocky outcrops on exposed outer coasts, which aren’t the easiest places to get to.

See? That’s a clump of Postelsia way out there in the center of the photo.

Rocks covered with olive-green seaweeds in the foreground and ocean in the midground, under a cloudy sky
Algae-covered rocks in the intertidal at Pigeon Point
2022-08-13
© Allison J. Gong

The tide was pretty good (-0.9 feet) so I figured it was worth working my way out there. I had a wishlist of critters to collect, but they would be pretty easy to find, and I had time to spend in the low intertidal. The algae are still going strong, although I did see some signs of senescence in some of the reds. The Postelsia, on the other hand, were in great shape.

Group of palm tree-shaped olive-green seaweeds attached to a rock in the intertidal.
Small stand of sea palms (Postelsia palmiformis) at Pigeon Point
2022-08-13
© Allison J. Gong

Despite its beautiful olive-green colors, Postelsia is a brown alga in the phylum Ochrophyta. It is in the same order (Laminariales) as the large canopy-forming kelps Macrocystis pyrifera and Nereocystis luetkeana. However, Postelsia gets to be only about a half-meter tall. It has a thick, flexible stipe and a cluster of thin blades at the top of the stop, which give it the palm tree appearance. Postelsia‘s hapterous holdfast does what it says on the label—it hangs on tightly to the rock. In fact, the rock often fails before the holdfast does, and when Postelsia washes up onto the beach it often has bits of rock (or mussel or whatever) still in the grip of the holdfast.

And it turns out that Postelsia is one of the many photogenic seaweeds. This morning it was doing the ’80s hair band thing. Especially when photographed from the vantage of a front-row groupie.

Postelsia palmiformis rocking the joint at Pigeon Point
2022-08-13
© Allison J. Gong

So that’s the organism that captured and held my attention this morning. The algae don’t get nearly the appreciation they deserve, even among fans of the rocky intertidal. Maybe shining a light on them once in a while is something I can do to fix that.

Earthwatch 2: Project ASCO

Posted on by Allison J. Gong

One of the reasons I selected this particular Earthwatch expedition was that it involved studies of both forest and ocean, which are my two favorite ecosystems here at home. I wanted to compare what I’m familiar with to similar habitats on the opposite coast. Regarding the rocky intertidal, I had been warned not to expect the spectacular biodiversity I’m used to on the Pacific coast, and that warning turned out to be quite a propos.

Along the California coast the rocky intertidal is an explosion of colors and textures, especially during the growing season. See this at Pigeon Point:

Ocean and seaweed-covered rocks
Rocky intertidal at Pigeon Point, San Mateo County, California
2022-06-01
© Allison J. Gong

and this at Asilomar:

Ocean and seaweed-covered rocks
Rocky intertidal at Asilomar, Monterey County, California
2022-06-03
© Allison J. Gong

And this is what you see when you walk—or in the case at Pigeon Point, climb down—to the site. It just is this varied, with several algae that are easily recognizable as being different even if you don’t know what their scientific names are.

Contrast that with the rocky intertidal at Frazer Point on the Schoodic Peninsula:

Coastline with small rocks covered with golden-brown seaweed
Mounds of Ascophyllum nodosum at Frazer Point on the Schoodic Peninsula
2022-06-17
© Allison J. Gong

All of the algae covering these rocks are rockweeds, and most of it is Ascophyllum nodosum. One of the projects we worked on was a study measuring the biomass of Ascophyllum on the coast of the Schoodic Peninsula. To do so we sampled along 30-meter transects in the intertidal, counting the number of Ascophyllum thalli in half-meter quadrats, looking for other algae and some key invertebrates, and weighing the Ascophyllum. This last part was new to me, and a lot of fun. It involved dividing the masses of Ascophyllum into as many as three bundles, wrapping it all up in a net like a burrito, and weighing the burrito using a hand-held metric scale.

Three people wearing yellow high-visibility vests kneeling among algae in the intertidal
Left to right: Sally, Alex, and Valerie weighing Ascophyllum at Frazer Point in Acadia National Park
2022-06-17
© Allison J. Gong

Clearly, Ascophyllum nodosum makes up the vast majority of biomass along this coastline. There are some other rockweeds in the genus Fucus, a bit of sea lettuce (Ulva sp.), and that’s about it. But the lack of diversity doesn’t mean the intertidal doesn’t have its own sort of spartan beauty. The lead for this project, Maya, described Ascophyllum as having a Van Gogh effect in the landscape. It didn’t take long to see what she meant. Check it out:

Ascophyllum nodosum at Frazer Point in Acadia National Park
2022-06-17
© Allison J. Gong

and

Ascophyllum nodosum at Frazer Point in Acadia National Park
2022-06-17
© Allison J. Gong

There are, of course, many types of beauty in the natural world. What I saw in the intertidal at Acadia wasn’t at all like what I’m used to seeing on the Pacific coast, but I wouldn’t say it is any less beautiful. The variation in color between new growth and the older parts of the Ascophyllum thalli makes for gorgeous patterns as the thalli drape over cobbles.

Besides, any morning in the intertidal is a good morning! I certainly wasn’t going to complain.

A most unusual sort of snail

Posted on by Allison J. Gong

One of the many delightful animals in the rocky intertidal is the vermetid snail, Thylacodes squamigerus. Unlike their more typical gastropod relations, the vermetids don’t live in a shell, per se. Instead, they live in a calcareous tube, which forms a loose coil draped over the surface of a rock. The tubes can be up to about 12 mm in diameter, and, if straightened out, about 15 cm long. In some locations, Thylacodes can be very abundant. In a recent visit to Point Pinos in Pacific Grove, I saw many of them in the low intertidal. I occasionally see them on the northern end of Monterey Bay and points farther north, but at nowhere near the abundance I see in Pacific Grove. At a larger scale, iNaturalist shows observations of T. squamigerus from northern British Columbia down to southern Mexico.

Three coiled white tubes and one spherical snail on a rock amid greenish seaweed
Trio of vermetid snails (Thylacodes squamigerus) with their more conventional cousin, the black turban snail (Tegula funebralis)
2022-06-03
© Allison J. Gong
Loosely coiled whitish tube on a rock
Thylacodes squamigerus
2022-06-03
© Allison J. Gong

Most snails are either grazers (e.g., abalones, limpets, turban snails) or predators (e.g., whelks, conchs, cone snails). Thylacodes is a bit of an outlier with regards to feeding as well as housing, for it is a suspension feeder. Being entirely sessile, it cannot go out and forage. And unlike its doppelganger, the tubeworms Serpula columbiana and S. vermicularis, Thylacodes does not create a water current to catch food on ciliated tentacles. Instead, it spins threads of sticky mucus that thrash around in the current and capture suspended detritus. When the tide is out the snail hunkers down in its tube, same as any worm. It cannot feed unless it is immersed. Where the worms live in the low intertidal on exposed rocky coasts, the water is moving constantly, and it requires relatively little energy for Thylacodes to feed the way it does. As a bonus, even the calories expended in producing the mucus are recouped, as the snail ingests the mucus strands as well as the food particles they capture.

When the tide came back, I got to watch Thylacodes in action. At Point Pinos there are some areas that form lovely tidepools, deep enough for animals to react to the return of the water and clear enough to make photography and videography possible. So standing knee-deep in a pool I stuck the camera underwater and hoped for the best. And I got lucky—you can see the mucus threads!

See here:

Thylacodes squamigerus
2022-06-03
© Allison J. Gong

and here:

Thylacodes squamigerus
2022-06-03
© Allison J. Gong

And not only that, but I captured some video footage. I use a point-and-shoot for these underwater shots, and usually don’t know what or whether I’ve shot anything good until I download images and video at home. Color me happy to have seen these clips!

Despite the unusual aspects of its biology, Thylacodes is indeed a snail. It has a conventional snail’s radula, and uses it the way, say, an owl limpet (Lottia gigantea) uses hers to scrape algae off rocks at Natural Bridges. Only instead of scraping the radula against rocks, Thylacodes uses its radula to reel in the detritus-laden mucus threads. That’s what’s going on in the second video clip above.

So there you have it, another of my favorite animals. Thylacodes is one of those animals that doesn’t look like much when you see it just sitting there. But we get to see it only during the tiny fraction of its life that it spends emersed. As with most inhabitants of the rocky intertidal, much of Thylacodes‘ life occurs out of sight for human eyes. This makes the occasional sighting of Thylacodes under water especially enlightening. And delightful!

Natural Bridges

Posted on by Allison J. Gong

Last week we had some of the best low tides of the season, and I was grateful to spend three consecutive mornings in the intertidal. The picture-taking conditions were fantastic when I went to Natural Bridges, and I snapped away like a madwoman. Unfortunately, last week was also finals week, and it wasn’t until I got all of the grading done and actual grades submitted that I let myself look at the photos. And there were a lot of good ones!

There are many wonderful things about the early morning low tides. One of the best is that most people prefer to remain in bed rather than get up before the sun and splash around in cold water. The past several weeks had been very busy, with little time for solitude, and I badly needed some time by myself in nature.

Usually when I post an entry here I have a story to tell. This time I don’t, unless the photos themselves tell the story. Let me know what you think.

Rocks covered in green surfgrass and brown seaweed, surrounded by water. Wave breaking in the background. Clouds in the sky.
Low intertidal at Natural Bridges
2022-05-17
© Allison J. Gong

Act I

At this time of year the algae are the stars of the show. They are at their most lush and glorious for the next several weeks.

Brown and dark iridescent seaweeds on rocks
Assemblage of mid-intertidal organisms
2022-05-17
© Allison J. Gong

Even in the sand, the algae were abundant and conspicuous. In the low intertidal the most prominent algae are the kelps. Here the feather boa kelp (Egregia menziesii) and the various Laminaria species are doing really well. Egregia also occurs higher in the intertidal, but Laminaria and Macrocystis (just visible along the right edge) are low intertidal and subtidal species.

Kelps (Egregia menziesii, Laminaria setchellii, and Macrocystis pyrifera) in the low intertidal
2022-05-17
© Allison J. Gong

My absolute favorite sighting of the morning was this group of algae on top of the sand. I love the way that the algae are splayed out. They are just so pretty!

Assemblage of algae in the sand
2022-05-17
© Allison J. Gong

Macrocystis pyrifera is justifiably well known as the major canopy-forming kelp along our coast. But it does occur in the low intertidal, as mentioned above.

Long strands of golden-brown seaweed
Giant kelp (Macrocystis pyrifera)
2022-05-17
© Allison J. Gong

Intermission

Act II

And now to focus on some individual organisms. Starting with my favorites, the anemones. This time it was the giant green anemone, Anthopleura xanthogrammica, that was the star of the show.

Large bright green sea anemone
Green anemone (Anthopleura xanthogrammica)
2022-05-17
© Allison J. Gong

I experimented with close-up shots, too!

Close-up of green sea anemone tentacles
Close-up of green sea anemone tentacles
Green anemone (Anthopleura xanthogrammica)
2022-05-17
© Allison J. Gong

There was a clingfish (Gobiesox meandricus), in its usual under-rock habitat. Don’t worry, I made sure to carefully replace the rock as I found it. This fish was about 10cm long. It may be the first clingfish I’ve ever seen at Natural Bridges. Clearly, I need to do more rock flipping.

Mottled brown fish with large head, on a rock
Northern clingfish (Gobiesox meandricus)
2022-05-17
© Allison J. Gong

A clingfish’s pelvic fins are fused together and modified to form a suction cup on the ventral surface. Clingfish can hop around a bit and are super cute when they eat. They sort of dart forward and land on the food, then shuffle around as they ingest it.

The coralline algae were both abundant and flourishing. They are looking fantastic this season. Someday I’ll study up on the coralline algae and write about them. For now, here are some happy snaps of Bossiella.

Pink, stiff, seaweed. Body of repeated sections.
Bossiella sp.
Pink, stiff, seaweed. Body of repeated sections.
Bossiella sp.
Pink, stiff, seaweed. Body of repeated sections.
Bossiella sp., one of the erect coralline algae
2022-05-17
© Allison J. Gong

Such a beautiful organism!

Sticking with the pink theme, another oft-overlooked organism is the barnacle Tetraclita rubescens. It has a few common names, including pink volcano barnacle and thatched barnacle. It is the largest of the intertidal barnacles along the California coast, and can be fairly abundant in some places. It is never as abundant as the smaller white (Balanus glandula) and gray/brown (Chthamalus dalli/fissus) barnacles, though.

Large pink barnacles on a rock
Tetraclita rubescens, the large pink barnacle
2022-05-17
© Allison J. Gong

Which brings us to my favorite color, purple. The tentacles of the sandcastle worm, Phragmatopoma californica, are a beautiful shade of purple. You don’t get to see the tentacles unless the worm is under water, and with the tide as low as it was when I was there this past week, it wasn’t easy finding any Phragmatopoma that were submerged. I’ve written about Phragmatopoma before, so won’t go into details here. But look at all those fecal pellets!

Tentacles of the sandcastle worm, Phragmatopoma californica
2022-05-17
© Allison J. Gong

And last but not least, here are a couple of the many purple urchins (Strongylocentrotus purpuratus) out there. At Natural Bridges there’s a large pool fairly high in the mid-intertidal that is called the Urchin Pool because it contains dozens (hundreds?) of urchins. Most of them are burrowed into the soft rock. Those are sort of easy pickings. I like finding urchins in less-obvious places, like these.

Purple urchins (Strongylocentrotus purpuratus) tucked into burrows
2022-05-17
© Allison J. Gong

Urchins in the intertidal often cover themselves with bits of shell, small pebbles, and algae. This helps them retain water as the tide recedes. At a location where the rock is soft, such as Natural Bridges, many of the urchins have grown larger than the opening to their burrow and cannot leave to forage; these imprisoned urchins have to wait for pieces of algae to drift nearby, which they can grab with their tube feet and then transport to the mouth on the underside. So long as they don’t get pried out by otters, the urchins seem to do just fine.

I think that’s enough for now. I hope these photos give you some idea of what it was like out there a week and a half ago. The next excellent low tide series is in mid-June. Snapshot Cal Coast will be in full swing then, so get out there if you can!