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About two and a half months ago, the ongoing disaster of sea star wasting syndrome raised its ugly head again when one of my bat stars (Patiria miniata) developed lesions on its aboral surface. Here's what it looked like then:

Patiria miniata (bat star) with small lesion. 4 September 2015 © Allison J. Gong
Patiria miniata (bat star) with small lesion.
4 September 2015
© Allison J. Gong

and here's a close-up of the lesion, taken the following day:

Lesion on aboral surface of Patiria miniata (bat star). 4 September 2015. © Allison J. Gong
Lesion on aboral surface of Patiria miniata (bat star).
5 September 2015.
© Allison J. Gong

See how the lesion is sort of fluffy? It looks as though tissue may be sloughing off the surface. Wanting to see how the syndrome would progress, I let it remain in its table and kept an eye on it. Every so often I took it out and examined it, and nothing really seemed to change. The animal continued to eat, retained its internal turgor pressure, and none of its table mates became sick. Eventually I sort of forgot about it.

Until two of my students last week asked if I had any pictures of sick sea stars that they could borrow for their end-of-the-semester project. This question jump-started my brain and I remembered this particular bat star, and told the students they could come to the lab and take their own pictures of it. . . that is, if it were still alive. They were able to visit me this past Monday and together we looked at the animal.

Lo and behold! it's not dead, and actually looks pretty good.

Patricia miniata (bat star) with aboral lesion. 24 November 2015 © Allison J. Gong
Patiria miniata (bat star) with aboral lesion.
24 November 2015
© Allison J. Gong

The star has a few pale areas in addition to the original lesions, but overall doesn't seem sick at all. It's nice and firm, righted itself quickly when we placed it in the bowl with its oral surface up, and crawled around very actively.

Not only that, but take a closer look at the lesion itself:

Lesion on the aboral surface of Patiria miniata (bat star). 24 November 2015 © Allison J. Gong
Lesion on the aboral surface of Patiria miniata (bat star).
24 November 2015
© Allison J. Gong

The lesion appears to be somewhat sealed off, as if the epidermis has recovered. I gently poked the surface of the lesion with my forceps, and it feels a little firm and nothing squirted out of or peeled off the surface of it. I think it's analogous to a scab that forms over a skinned knee. Of course, while a scrape on my knee would heal after a few days, sea stars have a much slower metabolism so I'm not really surprised that it would take over two months for this individual to show signs of a healing lesion.

Of course, I could be entirely wrong about what's going on with this lesion. It's the same size as it was back in September, so I'm not convinced that it's healing. However, it seems that closure of the wound is better than a wide-open gaping sore that leaves the animal's innards exposed to the external environment. If, over the next several weeks the edges of the wound begin to come together, then I'll be more confident that this animal is on the road to recovery. In this season on Thanksgiving, this is something to be grateful for.

A few weeks ago I made a pilgrimage to the Great Tidepool in Pacific Grove, where Ed Ricketts did much of his collecting in the 1920-40s. Ricketts is a legend among students of the intertidal here in California, but he is known to a much wider audience as the inspiration for the character Doc in John Steinbeck's novels Cannery Row and Sweet Thursday. Steinbeck and Ricketts were good friends, and in the spring of 1940 the two of them hired a seiner out of Monterey and her captain and crew for a six-week trip to collect intertidal invertebrates from the Sea of Cortez. The journal from that trip, published in 1951 as The Log from the Sea of Cortez, is a classic work of biology, philosophy, and adventure--one of my all-time favorite books and a definite recommended read.

Pacific Biological Lab, the home and workspace of Ed Ricketts. 14 November 2015 © Allison J. Gong
Pacific Biological Laboratories, the home and workspace of Ed Ricketts.
14 November 2015
© Allison J. Gong

For my birthday, I was treated to a tour of the Pacific Biological Laboratories on Cannery Row in Monterey. This is where Ricketts lived and worked. The original building on this site was completely destroyed in late 1936 by a fire that began at an adjacent cannery; Ricketts managed to escape with his typewriter but lost almost all of his collections, research notes, and scientific library. Fortunately for posterity, Ricketts' book on intertidal ecology, Between Pacific Tides, had already been sent to the publisher. Ricketts rebuilt his home and lab, which is the building that currently occupies the site. The city of Monterey provides free docent-led tours of the Lab on the second Saturday of every month.

I was primarily interested in Ricketts the scientist, although Ricketts the music-lover, poet, and philosopher was also discussed in the tour. We did get to see the building and back yard, including what the docent referred to as the "holy of holies," Doc's lab itself.

Bottles and jars at the Pacific Biological Laboratories. 14 November 2015 © Allison J. Gong
Bottles and jars at the Pacific Biological Laboratories.
14 November 2015
© Allison J. Gong

I love this old stuff, even though I probably don't want to know what was in any of these jars. Nor do I really want to be able to read the label on this bottle (okay, yeah, I really do):

Bottle with unreadable label. 14 November 2015 © Allison J. Gong
Bottle with unreadable label.
14 November 2015
© Allison J. Gong

I imagine that all the hazardous stuff was removed once the building became a museum, but the romantic in me wants to believe that these bottles still contain some essence of the work that went on in this room. Besides, I've encountered bottles that appear to be of not-much-younger vintage in old labs, and while they're undoubtedly scary they are also fascinating.

Ricketts' card catalog, which held his extensive collection records. 14 November 2015 © Allison J. Gong
Ricketts' card catalog, which held his extensive collection records.
14 November 2015
© Allison J. Gong

The most interesting artifact in the lab was this desk:

Steinbeck and Ricketts' desk. 14 November 2015 © Allison J. Gong
Steinbeck and Ricketts' desk.
14 November 2015
© Allison J. Gong

This is the very desk that Steinbeck and Ricketts purchased to take on their voyage to the Sea of Cortez. Unfortunately, they hadn't measured the berths on the boat they hired, and the desk didn't fit anywhere. It spent the entire voyage lashed down and covered with a tarp.

Ricketts' back yard holds a big rusted boiler that he used to render the livers of basking sharks (the smell must have been ungodly awful), as well as a series of concrete basins that he used as holding tanks for the animals he collected. The Pacific Ocean breaks literally against what would have been his garden wall if he'd had a garden.

Ricketts' back yard. 14 November 2015 © Allison J. Gong
Ricketts' back yard.
14 November 2015
© Allison J. Gong

Visiting this place made me aware that I hold a teensy bit of Ricketts' legacy in my hands whenever I teach about marine invertebrates or marine ecology. I certainly don't have Ricketts' poetic way of writing about these animals, but I hope that my students come away with a glimmer of what I love about them. And that I can be a conduit through which Ricketts' holistic view of the world he observed is transferred to another generation of naturalists. It's a big job, but somebody's gotta do it.

. . . taking a small group of highly motivated students into the field!

My invertebrate zoology class this semester has only 10 students, which allows me a lot more freedom to improvise on the fly and actually participate in the course instead of having to stand back and supervise 30 of them at the same time.

Most of my class getting started on their investigative journalist assignment at Point Pinos. 27 October 2015 © Allison J. Gong
Most of my class getting started on their investigative journalist assignment at Point Pinos.
27 October 2015
© Allison J. Gong

Their job was to interview at least six marine invertebrates and suss out answers to the Big 6 questions: Who? What? When? Where? Why? and How? In other words, to do a small bit of preliminary ecological investigation into animals they don't already know much about. Some of the students also used the time to scope out the site for their independent research projects, which they will be starting soon.


. . . serendipity!

This past couple of classes I lectured on Platyhelminthes and Nemertea, and we saw both on the field trip.

The flatworm, Eurylepta californica, was spotted by a keen-eyed student, who thought at first it was a nudibranch but then noticed the ruffling edge and decided it must be something else.

Eurylepta californica, the "chocolate drizzle" polyclad flatworm, at Point Pinos. 27 October 2015 © Allison J. Gong
Eurylepta californica, the "chocolate drizzle" polyclad flatworm, at Point Pinos.
27 October 2015
© Allison J. Gong

This individual was a bit less than 2 cm long. I've only seen it at Point Pinos. Such a cool animal!

Some day I want to find one of these at a site where I can collect, and bring it back to the lab for closer observation.

On each of these class field trips to the intertidal there's at least one conversation that goes something like this:

  • Student: Allison! I found this thing! What do you think it is?
  • Me, from several rocks over: Well, what does it look like?
  • Student gives a vague description, which usually isn't very helpful.
  • Me: Is it alive?
  • Student: I think so.
  • Me: Color?
  • Student: Sort of orange. (or brown or purple or whatever)
  • Me: Shape? Size?
  • Student: This big (holds up fingers or hands to indicate size, then describes shape).
  • Me: Is it hard or squishy?
  • Student: I don't want to touch it! Is it going to hurt me?
  • Me: Not unless it's a big crab. Just touch it and tell me what it feels like!
  • <pause>
  • Student: Hey, it didn't hurt me!

This conversation occurs as I make my way over to see what it is. Eventually I can take a look at the whatever-it-is and explain as best I can. The nemertean that we saw yesterday resulted in a conversation similar to this, but the student had pretty much decided on her own that she had found a nemertean. By the time I made it over to where she was pointing the worm had just about disappeared into a mussel bed, which is where they hang out. I could see enough to determine that it was Paranemertes peregrina.

Paranemertes peregrina, a nemertean worm, at Pistachio Beach. 31 January 2015 © Allisoin J. Gong
Paranemertes peregrina, a nemertean worm, at Pistachio Beach.
31 January 2015
© Allisoin J. Gong

Nemerteans are unsegmented, slimy, predatory worms that feed by shooting out a sticky proboscis and wrapping it around prey. Some have a stylet at the end of the proboscis with which they can repeatedly stab the prey and inject toxins. They may not be much to look at, but watching them in action should make you glad that you're not a small animal.


. . . being in the right place at the right time!

Yesterday we saw octopuses! Three of them, I think. And one of the most glorious sea anemones I have ever seen.

Octopus rubescens crawling around at Point Pinos. 27 October 2015 © Allison J. Gong
Octopus rubescens crawling around at Point Pinos.
27 October 2015
© Allison J. Gong
A beautiful Anthopleura xanthogrammica anemone at Point Pinos. 27 October 2015 © Allison J. Gong
A beautiful Anthopleura xanthogrammica anemone at Point Pinos.
27 October 2015
© Allison J. Gong

The octopuses that were out of the water were duly rescued by my students. The red one that I photographed turned out to about the length of my hand when it swam away into the depths of a tidepool. Watching the students release this little animal back into the water was a fitting way to close out what had been a fantastic field trip.

1

If I were the type of person to make and keep a bucket list, today I would have been able to cross off one item. For some reason until today I'd never managed to get to Ed Ricketts' Great Tidepool, even though I'd been several times to Point Pinos which is right around the corner. Today I had intended to do some collecting for a colleague back east, but it was just as well that those plans changed as I didn't find what I was supposed to collect. However, since I had blocked out the time I thought I might as well take advantage of the opportunity to scope out a new site.

Now that we're back in afternoon low tides, fighting darkness becomes a real problem. Today's low tide was at 16:28 and I had plenty of time to poke around and explore. Tomorrow I'm taking my class to the intertidal for an afternoon field trip, and on Wednesday I'll do some collecting of my own, almost literally racing against nightfall. Still, it was wonderful just to be out there again.

Sign

I'd heard about all the sea hares in the intertidal, and they were out in full force this afternoon. There were dozens of them, hanging out in ones and twos, either emersed or submerged just below the water line. They are big animals, about the size of a football, and silky soft to the touch.

California sea hare (Aplysia californica) in the Great Tidepool in Pacific Grove. 26 October 2015 © Allison J. Gong
California sea hare (Aplysia californica) in the Great Tidepool in Pacific Grove.
26 October 2015
© Allison J. Gong

The sea hares are herbivores, and they continued to munch on red algae even when completely emersed. At one point I accidentally either stepped on or kicked one, because suddenly the water around my feet started turning purple. I looked around for the culprit and found a large sea hare (almost half a meter long) heading towards the depth of a pool, oozing huge amounts of purple ink. And by "oozing" I really mean spewing. It looked like a volcano shooting lava into the water:

Color me impressed! Here's the animal that made all the ink:

California sea hare (Aplysia californica) exuding ink. 26 October 2015 © Allison J. Gong
California sea hare (Aplysia californica) exuding ink.
26 October 2015
© Allison J. Gong

It was a good day for molluscs. I saw a couple of these little chitons, Chaetopleura gemma. They are only about 1.5 cm long, and the ones I've seen in the field are orange, often with one of the valves an entirely different color.

Chaetopleura gemma, a small chiton. 26 October 2015 © Allison J. Gong
Chaetopleura gemma, a small chiton.
26 October 2015
© Allison J. Gong

And there were some other chitons, too. This is a beautiful specimen of Katharina tunicata:

The black katy chiton (Katharina tunicata). 26 October 2015 © Allison J. Gong
Black katy chiton (Katharina tunicata).
26 October 2015
© Allison J. Gong

In this species the girdle, the tough lateral edges of the mantle extend dorsally to nearly cover the eight plates on the back. They are one of the easiest chitons to identify in the field because of this feature.

And on my way out I saw a large (~7 cm) mossy chiton, Mopalia muscosa. These chitons can be fairly abundant at the sites I visit; every time I see one it's like meeting up with an old friend.

Mossy chiton (Mopalia muscosa). 26 October 2015 © Allison J. Gong
Mossy chiton (Mopalia muscosa).
26 October 2015
© Allison J. Gong

I find chitons very interesting, maybe because they can be quite abundant and yet are often overlooked. Many of them look not too different from the rocks they live on, and they don't exactly lead the most active lives when we see them. However, if we were to spy on them at high tide, I bet we'd see a lot more action from chitons. And maybe it's the very stillness of chitons that make them so easily foulable by other organisms. The Mopalia in the photo is host to a lot of spirorbids (tiny polychaete worms that live in spiral calcareous tubes) and various algae.


The Great Tidepool holds a special place in the hearts of marine biologists in the Monterey Bay region because it is where Ed Ricketts did much of his collecting and formulating the ideas that would become the field of marine ecology. He was a gifted writer and I find that his books convey not just his understanding of the rocky intertidal, but an affection for the animals that live there. Scientists are often assumed to be rather cold, dispassionate people; Ed Ricketts proved otherwise. If you've never read any of Ricketts' writings, I recommend Between Pacific Tides, as well as the memoir that he wrote with his friend John Steinbeck, Log from the Sea of Cortez.

I want to be Ed Ricketts when I grow up.

 

2

Let's just get this out of the way: I live in a paradise of natural beauty. Sometimes I still can't believe that I get to call this gorgeous place my home. However did I get so lucky?

Case in point. For the last week or so a juvenile humpback whale has been hanging out in a small cove right off the road that winds along the coast in Santa Cruz. Several of my friends had shown me pictures and video of it, but every time I went out I got skunked. I saw lots of seabirds, though, and that itself was pretty amazing.

Mitchell's Cove in Santa Cruz, CA. 16 September 2015 © Allison J. Gong
Mitchell's Cove in Santa Cruz, CA.
16 September 2015
© Allison J. Gong

Pelicans (Pelecanus occidentalis) and Caspian terns (Hydroprogne caspia) plunge-diving? Check. Common murres (Uria aalge) in the air and hanging out on the surface of the water? Check. Attempted kleptoparasitism by a gull on a tern that had caught a fish? Check. That was really cool. Oddly, though, I didn't see any sooty shearwaters today.

This past Saturday I went down to Mitchell's Cove and saw some amazing seabird behavior. The pelicans and terns were both plunge-diving, and then being mobbed by gulls and other hangers-on every time they came up with a fish. And in the background there was an unending stream of shearwaters flying from right to left.

I love how the pelicans fly along above the surface, then fold their wings and transform into arrows before shooting into the water. Good thing they don't have nostrils, isn't it? The terns do the same thing. Through the binoculars I watched the terns looking down for prey before committing to a dive; from what I could see they almost always came up with a fish.

The aforementioned humpback whale (Megaptera novaeangliae) was putting on a show this morning for the local humans. I wandered down at about 08:45 on my way to the marine lab. There were about 40 people scattered on the beach and along the side of the road. I settled myself on a rock with my camera and binoculars at hand. It took only a couple of minutes to see this:

Humpback whale (Megaptera novaeangliae) lunge-feeding at Mitchell's Cove in Santa Cruz, CA. 16 September 2015 © Allison J. Gong
Humpback whale (Megaptera novaeangliae) lunge-feeding at Mitchell's Cove in Santa Cruz, CA.
16 September 2015
© Allison J. Gong

Judging by size, this whale appears to be a juvenile. It was swimming just beyond the surf break, where the water was shallow enough that I could see the ripples just beneath the surface as the whale swam by. In this 2-minute video, the whale surfaces to breathe a few times and takes two lunging mouthfuls of fish and water before turning away and heading to slightly deeper water.

If I didn't have an actual job to do, I could have stayed out there longer, just to keep observing all the action. As it was, my arrival at the marine lab was delayed by about 40 minutes. Oh well. But I didn't have any time-crucial tasks or meetings this morning so nobody's schedule was affected except my own, and if I can't take advantage of serendipitous sightings like this then what's the point of living in paradise?

Late yesterday afternoon I met my friend Brenna at the harbor to go on a slug hunt. Brenna is working on the taxonomy of a group of nudibranchs for her dissertation, and we've gone collecting out in the intertidal together a few times. I knew I'd need some harbor therapy after teaching a microscope class in the afternoon so when she suggested a slug hunt I didn't have to think twice about saying "Yes!"

I arrived at the harbor before Brenna did, and spent some time lying on the docks taking pictures of the fouling community that lives there. The late summer afternoon light was perfect for picture taking, and I got some great shots.

Mussel (Mytilus sp.) at the Santa Cruz Yacht Harbor, 29 August 2015. © Allison J. Gong
Mussel (Mytilus sp.) at the Santa Cruz Yacht Harbor, 29 August 2015.
© Allison J. Gong

This is one of my favorites. It's a view into the posterior end of a live mussel (Mytilus sp.). Mussels live inside a pair of shells and open up only the posterior end to suck in water for respiration and filter feeding. They shut the shells very quickly when disturbed, so I had to sneak up on this individual and take a picture before it knew I was there. Looking through the opening you can see a blurry pale structure running from left to right; I think this is the mussel's gill. The elaborately fringed dark structure that looks like a pair of curtains extending towards each other is the edge of the mantle. Because most of the mussel's body is enclosed within the shells, the mantle edge contains most of the animal's sensory organs. Mantles are exquisitely sensitive to touch, light, and certain chemicals; scallops, another type of bivalve mollusk, often have actual eyes on the mantle edge.

In addition to spying on mussels, I also tried to catch polychaete worms off-guard. There are several different types of tube-dwelling polychaetes living at the harbor. Most of the ones I saw yesterday were serpulids living in meandering calcareous tubes. Like these:

Serpulid polychaete worm at the Santa Cruz Yacht Harbor, 29 August 2015. © Allison J. Gong
Two examples of Serpula columbiana, a tube-dwelling polychaete worm, at the Santa Cruz Yacht Harbor, 29 August 2015.
© Allison J. Gong

Polychaete worm tubes come in many different materials and morphologies. These serpulids live in calcareous tubes that snake over surfaces. Because the tubes are mineralized, they can extend upwards from a surface, too. The worm spends its entire post-larval life in the tube that it secretes, extending only its "head", visible as a tentacular crown, for filter-feeding. Like the mussels, serpulid polychaetes are very quick to respond to anything they perceive as a threat. Even a mere shadow passing over them can cause a rapid retreat into the tube finalized by sealing off the tube with the trumpet-shaped operculum.

One of the most conspicuous animals at the harbor is an invasive encrusting bryozoan, Watersipora subtorquata. This animal is one of the first to colonize new real estate. Nothing else looks like it, so it is easy to identify.

Watersipora subtorquata, an introduced bryozoan at the Santa Cruz Yacht Harbor, 29 August 2015. © Allison J. Gong
Watersipora subtorquata, an introduced bryozoan at the Santa Cruz Yacht Harbor, 29 August 2015.
© Allison J. Gong

Watersipora grows as a crust on surfaces such as mussel shells and floating docks, but when two colonies meet they use each other as surfaces, forming these curling sheets. The faint fuzziness that you see sort of hovering above the surface of the sheets is due to the lophophores extending from the zooids. Here's a closer shot:

Watersipora subtorquata, an introduced bryozoan at the Santa Cruz Yacht Harbor, 29 August 2015. © Allison J. Gong
Watersipora subtorquata, an introduced bryozoan at the Santa Cruz Yacht Harbor, 29 August 2015.
© Allison J. Gong

Another of the common introduced species at the harbor is the colonial sea squirt Botrylloides violaceus. This animal comes in a wide range of oranges and even purple. Here's a colony that seems to understand the visual impact of pairing high-contrast colors:

Colony of the colonial sea squirt Botrylloides violaceus growing over mussel shells at the Santa Cruz Yacht Harbor, 29 August 2015. © Allison J. Gong
Colony of the colonial sea squirt Botrylloides violaceus growing over mussel shells at the Santa Cruz Yacht Harbor, 29 August 2015.
© Allison J. Gong

What looks like a mass of pale orange doughnuts is actually a strictly organized colony. Each of the doughnuts is a zooid, and the hole of the doughnut is the incurrent siphon through which the zooid draws water in. Each zooid has its own incurrent siphon. In this photo you can see several larger holes; these are excurrent siphons, shared by several zooids, through which waste water is expelled. It's difficult to see in the photo, but the excurrent siphons are raised up above the level of the colony, so water that has already been filtered doesn't get sucked in again. This is exactly the reason that human structures such as smokestacks and chimneys are tall.

Oh, and since you asked, Brenna did indeed find slugs! And she taught me some field characteristics to help me ID slugs that I find. We both got what we needed on our little jaunt to the harbor.

Day 3 of wasting in Leptasterias

The saga continues. When I checked on my ailing stars yesterday I saw, as expected, that most of what I had called Leptasterias #1 (the pink star that had ripped itself into pieces the day before) had disintegrated into small piles of mush. There was no sign of life in any of the small fragments so I threw them away. The largest piece, consisting of two adjacent arms attached to what looks like most of the central disc, was still walking around so I kept it. Today I was surprised to see that it hasn't died yet. In fact, it looks a little better, with both of the arms active and the central disc appearing to be somewhat more contracted and less sloppy.

Remnant of wasting Leptasterias star, 30 August 2015. © Allison J. Gong
Remnant of wasting Leptasterias star, 30 August 2015.
© Allison J. Gong

The two arms appear to be working together, rather than trying to walk away from each other. I think this is a good sign, although it's too early tell how much longer this fragment of a star will survive.


The star I had designated Leptasterias #2, which had the very large lesion on Friday, had died and dissolved into a mass of amorphous tissue and skeletal ossicles when I looked at it yesterday.


On the other hand, Leptasterias #3, the larger of the two gray stars, seems to be holding its own, or at least not getting any worse. On Day 1 of the outbreak this star had a small fluffy lesion on its aboral surface. Today the wound appears to have grown a bit but its edges look a little cleaner:

Leptasterias star affected by wasting syndrome, 30 August 2015. © Allison J. Gong
Leptasterias star affected by wasting syndrome, 30 August 2015.
© Allison J. Gong

This star was particularly active this morning. I didn't want to disturb it or give it any incentive to autotomize its arms, so I left it in its screened container to take pictures and video. It was zooming around and acting, for all intents and purposes, like a normal healthy star.

Fingers crossed that this one makes it!

Sometimes the only word that will do is a bad word. I generally try not to use a lot of bad language because on the occasions when I do swear I want my f-bombs to really mean something. Late this afternoon I was on my way out of the lab when I made a quick last trip through the wet lab just to make sure everybody would be okay for the night, when out of the corner of my eye I saw a few odd pink bits in one of my screened containers.

This container held three small six-armed stars of the genus Leptasterias. I had collected them earlier this summer with the goal of showing them to my students when we do the echinoderm diversity lab at the end of the semester. Stars in this genus are interesting because their normal arm number is six and they brood their babies instead of broadcasting gametes into the sea to meet, fertilize, and develop on their own. Plus, like all their echinoderm kin, they are pretty animals. Lastly, enamored as I am of oddballs and out-of-the-ordinary things, I am charmed by Leptasterias's six arms because most stars have only five.

So when I opened up the screened container and saw that one of my Leptasterias stars had torn itself into pieces, I let fly with a few f-bombs and other choice expletives. I removed the star pieces into a bowl for a better view.

Leptasterias star dismembered due to wasting syndrome, 28 August 2015. © Allison J. Gong
Leptasterias star dismembered due to wasting syndrome, 28 August 2015.
© Allison J. Gong

Seeing a star that had ripped its own arms off is every bit as horrifying when the star has six arms as when it has five. This act of self-mutilation had probably occurred today, as the star looked fine when I checked on it yesterday. All of the pieces were still alive and crawling around:

Actually, if you examined each of the pieces independently and didn't know that it was only part of a greater whole, you'd think that they were entirely viable. I put these pieces aside in a separate bowl, although honestly I don't know why. I'm almost certain they'll be dead when I check on things at the lab tomorrow morning, and even if they aren't they'll be decomposing while still sort of alive, which is even worse. I must be a glutton for punishment.

For a while I held out a teensy glimmer of hope that the other two stars might be okay, but that didn't last long. It took only a glance to see a big aboral lesion on the center of one of them:

Leptasterias star with large aboral lesion, 28 August 2015. © Allison J. Gong
Leptasterias star with large aboral lesion, 28 August 2015.
© Allison J. Gong

Examination under higher magnification shows just how deep and intrusive these lesions are. The body wall is entirely compromised, resulting in the exposure of internal organs to the outside environment.

Lesion on aboral surface of Leptasterias star, 28 August 2015. © Allison J. Gong
Large lesion on aboral surface of Leptasterias star, 28 August 2015.
© Allison J. Gong

It turns out that none of these Leptasterias is unaffected. The third star in my container has a small aboral lesion:

Small aboral lesion on Leptasterias, 28 August 2015. © Allison J. Gong
Small aboral lesion on Leptasterias star, 28 August 2015.
© Allison J. Gong

Whether or not this third individual will survive is up for grabs, but I wouldn't bet on it. From my experience with wasting syndrome in Pisaster and Pycnopodia, the disorder progresses extremely rapidly once the animal starts showing signs of illness. And all of these animals appeared just fine yesterday. The small pink star is essentially dead already, it just hasn't realized it yet. The gray star with the large lesion may very well be dead tomorrow, too. The star with the small lesion might still be alive tomorrow, and this is the only one for which I have a bit of hope for survival.

About a week ago the seawater temperature dropped to 16°C for a few days, but then started creeping back up; today it topped out at 19°C. Correlation is not causation, but I do wonder if another spike in the 19-20° range, on top of stress caused by the ongoing period of warm water, is the proverbial straw that broke the camel's back. These poor stars have gone through hell lately, and there's no indication that the water will cool off any time soon. I'd throw up my hands and ask, "What's next?" but I have a sneaking suspicion that I'll find out soon enough.

1

Having read multiple news accounts of domoic acid (DA) events up and down the Pacific coast of the U.S., I decided to do my own informal survey of the culprit that makes DA. Domoic acid is a naturally occurring toxin that is produced by some (but not all) species of the diatom Pseudo-nitzschia during a plankton bloom. It is ingested by filter-feeding animals such as mussels and anchovies and gets passed to higher trophic levels as these animals are themselves preyed upon. The filter feeders are thought to be unaffected by the DA they ingest, but due to bioaccumulation the toxin occurs in higher concentrations in the tissues of the predators. Humans can be affected by DA also, when they eat contaminated shellfish, for example. This is why coastal states advise seafood foragers not to collect and eat bivalves (clams, mussels, oysters) when DA is detected in the water. When humans are sickened by domoic acid, the affliction is called Amnesic Shellfish Poisoning (ASP).

I had originally hoped to collect a sample from a boat over deeper water, but when those plans failed to materialize I did the best I could on my own:  I went out to the end of the Santa Cruz Municipal Wharf and threw the net from there. As soon as I hauled the net back up I could smell the diatoms. Yes, diatoms have a smell, as does just about anything when you concentrate it enough. The diatom smell is rich and organic, but not at all unpleasant.

This is what the sample looked like:

All those clear needle-like things are chains of Pseudo-nitzschia cells. When they are reproducing quickly (a.k.a. "blooming") the cells remain connected by their tips (see below). Longer chains indicate favorable conditions for asexual reproduction in diatoms; I saw some chains that were 12+ cells long. The small whitish things zooming around are barnacle nauplii. Obviously barnacles are having lots of sex right now.

Pseudo-nitzschia is a pennate diatom, which simply means that the cells are pen- or boat-shaped. Some of the pennate diatoms have a raphe, or slit-like opening on the frustule through which a tiny bit of protoplasm can be extruded. These diatoms, of which Pseudo-nitzschia is one, don't swim but can actually scoot around on surfaces. Don't believe me? Then watch this long chain of Pseudos move back and forth like a train on tracks.

Here's a still shot at higher magnification:

Cells of the pennate diatom Pseudo-nitzschia sp. 21 August 2015. © Allison J. Gong
Cells of the pennate diatom Pseudo-nitzschia sp. 21 August 2015.
© Allison J. Gong

See how the individual cells remain connected to each other by their overlapping tips? Each of the cells is about 75 µm long and contains two roughly rectangular chloroplasts that are golden brown in color.

Pseudo-nitzschia wasn't the only diatom in the sample, either. I saw surprising numbers of Coscinodiscus, a genus of centric diatoms, ranging in size from 160-250 µm in diameter. Coscinodiscus frustules are beautifully sculptured, making the cells look like fancy buttons.

Cells of the centric diatom Coscinodiscus sp. 21 August 2015. © Allison J. Gong
Cells of the centric diatom Coscinodiscus sp. 21 August 2015.
© Allison J. Gong

That little bleb at about 10:00 on the larger diatom is a dinoflagellate, Peridinium or Protoperidinium, that came along for the ride. There is also a chain of Pseudos making a cameo appearance in the bottom of the photo.

The other unusual diatom in the sample was Chaetoceros. This diatom has a name that hints at the morphology of the cells:  "chaet-" is Greek for "spine" or "bristle". Indeed, the cells of Chaetoceros are box-shaped and have four long spines that link adjacent cells together to form chains.

Cells of the centric diatom Chaetoceros sp. 21 August 2015. © Allison J. Gong
Cells of the centric diatom Chaetoceros sp. 21 August 2015.
© Allison J. Gong

The intriguing question that came to my mind was "Why now?" Around here I've grown accustomed to a typical succession of phytoplankton in Monterey Bay, with diatoms (especially Chaetoceros) blooming in the spring and early summer, corresponding to our usual upwelling season, then giving way to dinoflagellates in the late summer and fall when upwelling abates. And yes, we did have a major Pseudo-nitzschia bloom back in April and May. Diatoms bloom in response to high levels of nutrients, especially nitrate, that occur when upwelling returns nutrients to surface waters. We did have a few weeks of decent upwelling in the spring. Then El Niño started to build and we went through several weeks of warm, clear water when diatoms were pretty much absent and we saw phytoplankters such as silicoflagellates and coccolithophores, which can thrive in waters that are too nutrient-depleted for diatoms.

And now the diatoms are back. Chlorophyll levels in nearshore waters are high right now all along the central California coast. These data are from CeNCOOS, an ocean observing system:

Chlorophyll concentrations along the central California coast, 17-19 August 2015. © CenCOOS
Chlorophyll concentrations (µg/L) along the central California coast, 17-19 August 2015.
© CeNCOOS

Assuming that the chlorophyll being measured is in the cells of Pseudo-nitzschia and other diatoms, it appears that we're having a return to springtime conditions. Bait fish are back in the Bay, and following them are dolphins and birds. I would dearly love to do some whale watching this fall; we may have another spectacular season for humpback whales. Whatever the cause for this apparent late-season rebirth, this autumn is shaping up to be interesting.

5

Next week classes for the Fall semester begin, and this will be my fourth term teaching a marine invertebrate zoology class at this particular institution. I have built this class on a foundation of comparative anatomy and functional morphology; lab activities include dissections (to observe how bodies are put together) and diversity labs (to examine the morphological diversity within major taxa). This year I wanted to include a lab with a broader ecological context. So back in April I hung a box of glass slides from one of the boat slips at the harbor. The idea is that the students in the invert zoo class will examine the slides after they'd been marinating in the ocean for several months and have to figure out what's growing on them.

The organisms that have and will continue to colonize the slides are members of what is rather disparagingly referred to as a "fouling community." To be fair, they can be nuisances, fouling docks and pilings, boat hulls, water intake and outflow pipes, and pretty much anything that is left in the water for any significant amount of time. In fact, my friend Adam has a job scraping fouling organisms off the bottoms of boats at the harbor; boat owners either pay to have this done or do it themselves every so often. But to me, these animals and algae form a fascinating ecological community that illustrates many of the principles I teach to my students.

Harbors are some of the places where exotic (i.e., non-native) species are first detected. It is not uncommon for many of the species in a fouling community to have evolved elsewhere and been transported (usually, but not always, unintentionally) to a new location, where they grow swiftly and often out-compete the native species. Obviously, not all species introductions "take" and it's anybody's guess how many species were dumped in a new site and failed to stick around. The ones that do take, though, tend to become very prominent.

So, back to my slide box. It was still there, hanging from a string about 2.5 meters below the bottom of the dock. As I pulled it up, I was relieved to see different colors and textures:

Slide box hanging from a floating dock at the harbor. 20 August 2015. © Allison J. Gong
Slide box hanging from a floating dock at the harbor. 20 August 2015.
© Allison J. Gong

Up close, it looked even more promising:

Slide box hanging from a dock at the harbor. 20 August 2015. © Allison J. Gong
Slide box hanging from a dock at the harbor. 20 August 2015.
© Allison J. Gong

Even without knowing what all the differently colored blotches are, you can tell that there's a lot of stuff growing. I'm not going to dismantle the box until we use it in lab in early November, but I thought it might be worth a closer look. It just so happened that I had both a clean bucket in my car and the foresight to bring it with me onto the dock. This photo shows that the slides themselves are covered with growth:

Slide box hanging from a floating dock at the harbor. 20 August 2015. © Allison J. Gong
Slide box hanging from a floating dock at the harbor. 20 August 2015.
© Allison J. Gong

The red encrusting sheet is the bryozoan Watersipora, probable species subtorquata, an invasive species that is found in harbors all along the California coast. The pale orange blobs are colonies of sea squirts; it is difficult to identify them to species without examination under a microscope. There is also quite a bit of a brown upright branching bryozoan that I think belongs to the genus Bugula.

As an unabashed aficionado of all things hydroid, I'm always very pleased to see certain species of 'droids at the harbor. They are simply so beautiful that I love looking at them. This is the hydroid Ectopleura crocea. It is common but sporadic and patchy at the harbor, and usually isn't one of the first species to colonize an area. Its congener, E. marina, occurs in the intertidal; I can find it fairly reliably in a particular pool at Davenport Landing and have occasionally seen it elsewhere.

Ectopleura crocea growing out of a colony of Watersipora subtorquata. 20 August 2015. © Allison J. Gong
The hydroid Ectopleura crocea growing out of a colony of Watersipora subtorquata. 20 August 2015.
© Allison J. Gong

Having reassured myself that my slide box was doing well I took some time to check out other bits of real estate in that area of the dock. I played around with the super-macro setting on my camera, with mixed results. I do now know, though, that it works underwater:

Tentacular array of a serpulid polychaete worm. 20 August 2015. © Allison J. Gong
Tentacular array of a serpulid polychaete worm, with bryozoans in the background. 20 August 2015.
© Allison J. Gong

I found a cooperative barnacle and took some video footage of feeding behavior. Barnacles are strange crustaceans that lie on their backs and kick their modified thoracic appendages through the water to capture small particles. What a weird way to make a living. But the animal is always right, and barnacles can be quite efficient at clearing water.

And, finally, does anybody know the source for the title of this post? Answer in the comments section, please!

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