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Much ado is being made of the fact that Africanized honey bees have recently been found in the San Francisco Bay Area. Most of the articles I've read on the subject have disseminated information that is good, but can be confusing to the average person who isn't a beekeeper. Most people who don't understand bees fear them, and only want to know: (1) Should I be worried? and (2) How much should I worry?

First, some background: The European honey bee (Apis mellifera) was introduced to North America with the first European settlers on the continent. It is a docile bee, easy to work with, and generally a good honey producer. Several strains, or subspecies, of A. mellifera have been bred over the years, resulting in stocks that beekeepers refer to as Italians (A. mellifera ligustica), Carniolans (A. mellifera carnica), Russians, and others. Beekeepers choose strains of bees that suit their preferences, in terms of temperament, honey production, speed of colony build-up, and disease or parasite resistance.

One of our bees, probably an Italian, on the screen door. 26 July 2915 © Allison J. Gong
One of our bees, probably an Italian, on the screen door.
26 July 2915
© Allison J. Gong

We began our beekeeping adventures with two packages of Italian bees, which proved to be very sweet and extremely productive. Most of our mentors told us not to expect to harvest any honey our first season, as the bees would be busy growing the colony and finding enough food to feed themselves over the winter, and yet we harvested over 100 pounds of surplus (i.e., beyond what the bees needed to overwinter) honey. Since then we've not had to buy packages again and have acquired colonies by either catching swarms (fun!) and splitting our existing hives.

Occasionally a beekeeper has to re-queen a hive, to replace one that has gone missing or is failing to lay well. Sometimes the bees take matters into their own hands(?) and rectify a situation that they feel is lacking; they will build a new queen from one of their sister larvae, who will supplant their collective mother and take over the egg-laying duties. We have re-queened hives that are bitchy, the ones in which the bees fly up at us the moment we crack the hive open and bang into our veils. I don't like to work with pissy bees, and while I know I shouldn't be afraid of our bees, I've had a bad enough sting reaction to warrant allergy tests that determined I have a mild-moderate allergy to honey bee venom. So I'd much rather work with sweet bees, like Italians or Russians that just look up at us from between the frames or keep going about their business as we tear apart their home.

Calm bees walking around on the top bars of frames. 11 April 2015 © Allison J. Gong
Calm bees walking around on the top bars of frames.
11 April 2015
© Allison J. Gong

How and why does a colony of mild-mannered, easy-to-work-with bees become a nightmare to deal with? What happens probably goes something like this. Worker bees may decide, over the course of a season, to supersede their mother and re-queen their colony. The new queen, who is the sister of the workers, flies out and mates with a dozen or so drones from other colonies, then returns to her natal hive to begin laying. If she mated with drones who carry Africanized alleles, then some of her offspring will possess those alleles. A beekeeper with a hive that has become more defensive can change its overall temperament by introducing a new queen that comes from a lineage known for its gentleness.

More about the Africanized bees: Africanized honey bees are the result of inadvertent hybridization between strains of the European honey bee, including the Italian A. mellifera ligustica, and the African bee, A. mellifera scutellata. The African bee was imported to a lab in Brazil in the mid-20th century, when beekeepers were attempting to increase honey production. It escaped from quarantine in 1957 and began hybridizing with the European honey bees that had been established in the New World for centuries. It has been expanding its range northward since; the first reports of Africanized bees in southern U.S. states were in the early 1990s. They have been in southern California since 1994.

An Africanized honey bee has a sting that is no different from that of a European honey bee, and she will still die when she stings someone. The difficulty, as far as humans and livestock are concerned, is that Africanized bees are much more defensive of their colonies and are generally easier to piss off. When they perceive a threat they usually  emerge from the hive in great numbers and attack the intruder. They have also been known to chase people long distances and keep attacking. People who accidentally upset a colony of Africanized bees tend to get stung dozens or hundreds of times, and the accumulation of that much venom can be fatal.

The only way to know for certain that a bee is Africanized is to examine her genome for African alleles. We know now that Africanized honey bees are in the Bay Area. Whether or not they become permanently established remains to be seen, but if there's one Africanized colony surely there must be others.

So, should you be worried? In my opinion, there are lots of things that are more worrying than Africanized honey bees. Then again, where I live they haven't been around very long and I've never encountered a purely Africanized colony. If we have bees in our hives that are pissy we re-queen the colony, so it's unlikely that any of our colonies will be taken over by Africanized bees. However, this is a biological system we're talking about, so nothing is guaranteed.

Here in northern California, most beekeepers aren't too worried about Africanized bees because we think they won't survive our winters. That said, we're heading into a pretty strong El Niño event and may not have a cold winter this year, although we all hope it's a rainy one (and a snowy one in the Sierra Nevada). Plus, with climate change and a generally warming planet, conditions that favor survival of the Africanized bee may soon prevail in much of the U.S. Residents of the southern U.S. should probably take care not to disturb a colony of feral bees because they may be Africanized. Call a beekeeper (not an exterminator!) and let a professional deal with it. Bees (both European and Africanized) that are foraging, though, tend to be focused on the job at hand and won't bother you unless you bother them first. Just leave them alone and watch from a safe distance.

This morning I was doing some routine cleaning of animal-containing dishes at the marine lab when I noticed a little blob of snot on the outside of the bowl I was working on. Normally I just wipe off blobs like that, but something about this one caught my attention in a different way and I paused to take a closer look at it. What I saw made me glad I hadn't given it the old Kim-Wipe™ treatment.

It was this:

Very small juvenile nudibranch (Melibe leonina). 23 September 2015 © Allison J. Gong
Very small juvenile nudibranch (Melibe leonina).
23 September 2015
© Allison J. Gong

This little 3mm blob of cuteness is the tiniest Melibe I've ever seen. Melibe is one of my favorite creatures of all time. It's an entertaining animal that has unfathomable amounts of charm. Unlike most other nudibranchs, which prey on other animals (typically cnidarians, sponges, or bryozoans), Melibe is a filter feeder. It sweeps its large oral hood, visible to the right, through the water to capture plankton. The flat large-ish structures projecting from the animal's back like wings are cerata, of which there will eventually 4-5 pairs when the slug reaches adult size. The cerata function as gas exchange surfaces; they also contain extensions of the digestive system. When a Melibe is mishandled or stressed, it drops cerata, which can then be regenerated.

Melibe is the most animated of slugs. I dropped a few brine shrimp nauplii on this little guy to see if it would be able to catch them. Unfortunately it looked more like the nauplii were ganging up on the Melibe than the other way around. However, I know from experience that even larger Melibe take a while to figure out how to eat brine shrimp.

But isn't that the cutest slug you've ever seen? It has tiny bright blue dots on its body! Those two little flaps on the top surface of the oral hood are rhinophores. I know they look like ears, but they are chemosensory rather than auditory organs.

And look how fast this little nudibranch can crawl! Remember, it's only 3mm long, and it's making pretty good progress getting to the corner of the bowl.

When dislodged from whatever it's crawling on, Melibe can swim. I thought this one would attach itself to the underside of the surface tension, as they often do, but it thrashed for quite a while before sort of accidentally finding the bottom of the dish again.

And do you know what the best thing about Melibe is? It smells like watermelon. I kid you not. If you touch a Melibe, your finger will smell like watermelon Jolly Ranchers. How could an animal possibly be any cooler than that?

In a desperate attempt to escape from the heat yesterday afternoon I went down to the marine lab and vowed to find something to do that would keep me there for a while even though I had only a few minor chores to take care of. Fortunately there was a lot going on in the ocean. The tide was high, almost completely covering the intertidal benches where I spent so much time this spring and summer. And there, right up against the cliff, were hundreds of seabirds, squawking and squabbling over fish. Pelicans, terns, gulls, and cormorants were all mixed together in a big scrum of activity.

Pelicans 20 September 2015 © Allison J. Gong
Pelicans, Caspian terns, assorted gulls, and cormorants at Natural Bridges State Beach.
20 September 2015
© Allison J. Gong

The brown pelican (Pelecanus occidentalis) is described by the Cornell Lab or Ornithology as a "comically elegant bird" and it's hard not to agree. However, watching them in flight over the ocean makes me reconsider. When I see them in the air I find them to be not just elegant, but graceful as well.

Brown pelicans in flight over Monterey Bay off Terrace Point. 20 September 2015 © Allison J. Gong
Brown pelicans in flight over Monterey Bay off Terrace Point.
20 September 2015
© Allison J. Gong

While the birds were making a fuss over anchovies that had been pushed close to shore, six harbor seals (Phoca vitulina) were lounging lazily just off the point. They would roll around at the surface, diving underneath waves as they broke onto the rocks. Because the tide was high the seals were floating over intertidal benches that I explored during the spring and summer. They didn't seem to be feeding on anything at the time.

As you might expect with all the feeding frenzy going on, a couple of humpback whales came to the show. They were out beyond the kelp bed, far enough away that I could have missed them if I didn't have my binoculars with me. I didn't see any lunge-feeding from this pair, which left more food for the birds.

After I'd been watching the feeding activity for about an hour and a half, I heard the familiar high-pitched 'cheep-cheep-cheep-cheep-cheep' of one of my favorite local seabirds, the black oystercatcher (Haematopus bachmani).

Black oystercatchers (Haematopus bachmani) at Natural Bridges. 20 September 2015 © Allison J. Gong
Pair of black oystercatchers (Haematopus bachmani) at Natural Bridges.
20 September 2015
© Allison J. Gong

I love these birds for a couple of reasons: (1) I have NEVER seen a single oystercatcher, I have seen them only in what I assume are mated pairs (there is no sexual dimorphism in this species so it's impossible to distinguish between males and females); and (2) they almost always show up to keep me company when I'm in the intertidal, especially at Davenport Landing. They are also noisy birds, both in flight and while walking around on mussel beds. They have a dark sooty brown body and a long, stout, bright red beak that contrasts nicely and is the perfect tool for prying open mussels or flipping limpets off rocks. This particular pair didn't join in the hullabaloo over anchovies, since oystercatchers don't eat fish. I watched them prowl around on the rock bench, where the tide was really too high for them to have access to the mussels.

I remain grateful for a cool place to retreat to when it gets hot in Santa Cruz. We are in strange times, weather-wise, and I don't think anybody really knows what to expect over the next few months. All I know is that I hope we don't get any more of these blazing hot spells.

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?

. . . clam, right? Yes, except in this case the bivalve is not a clam, but a scallop. I was out at the harbor with Brenna again this morning, looking for molluscs for tomorrow's molluscan diversity lab. Brenna was hunting for slugs, of course, and had drawn up a rope that had been hanging in the water for god knows how long. Neglected ropes like this are the stuff of dreams for people like Brenna and me, as all sorts of animals recruit to and colonize them. Hauling one up is like going on a treasure hunt.

Two of the animals that had attached to the rope were small kelp scallops, Leptopecten latiauratus. The smaller of the two was about the size of my thumbnail and the larger was about 1.5 times that size. Their shell patterns are very beautiful:

The larger rock scallop (Chlamys hastata) collected at the Santa Cruz Yacht Harbor. 14 September 2015 © Allison J. Gong
The larger kelp scallop (Leptopecten latiauratus) collected at the Santa Cruz Yacht Harbor.
14 September 2015
© Allison J. Gong
The smaller rock scallop (Chlamys hastata) collected at the Santa Cruz Yacht Harbor. 14 September 2015 © Allison J. Gong
The smaller kelp scallop (Leptopecten latiauratus) collected at the Santa Cruz Yacht Harbor.
14 September 2015
© Allison J. Gong

But really, you don't get a feel for how much fun these animals are until you watch them. Scallops are the most animated of the marine bivalves. They have eyes and sensory tentacles along the ventral edge of the mantle, and react strongly to stimuli. They can clap their valves together so quickly that they actually swim. I wasn't able to make either of mine swim, but did get to watch them for a while.

The whitish object waving around on the left side of the frame is the scallop's foot. Rock scallops are not permanently attached to surfaces (if they were, they wouldn't be able to swim!) but they do use the foot to stick. If they find a spot they like, they try to wedge the dorsal, hinged area of the shell into a crevice.

Just like you and me, scallops have bilateral symmetry, complete with left and right sides. Unlike you and me, however, their bodies are laterally flattened and entirely enclosed between the left and right shells. The only parts of the body that extend from between the shells are the foot and the sensory structures on the mantle edge. Leptopecten has many long filament-like sensory tentacles, and brilliant blue eyes.

I thought I'd provoke a reaction by passing my finger over the animal and casting a shadow over it. Nada. But then it closed its shells a couple of times for no reason that I could discern. However, as my graduate advisor Todd Newberry used to say, The Animal Is Always Right™, and what doesn't seem like anything to me could very well be a threat to a scallop.

And by the way, I did also collect a few slugs and a chiton for tomorrow's lab. The highlight for me, though, was the scallops. I hope my students are as captivated by these little bivalves as I was!

1

The Seymour Marine Discovery Center, where I spend some time hanging out several days a week, has a spiny lobster (Panulirus interruptus) on exhibit. While the lobster doesn't have an official name, for obvious reasons the aquarists call it Fluffy. We don't know if Fluffy is male or female, but for convenience sake we've been referring to it as 'he' which may or may not be sexist, depending on one's point of view. Fluffy came to the Seymour Center as a full-grown adult in September (I think) of 2012 and has molted every year close to the anniversary of his arrival.

Fluffy, the spiny lobster (Panulirus interruptus) on exhibit at the Seymour Marine Discovery Center. 7 September 2015 © Allison J. Gong
Fluffy, the spiny lobster (Panulirus interruptus) on exhibit at the Seymour Marine Discovery Center.
7 September 2015
© Allison J. Gong

Fluffy's latest molt occurred some time between Saturday afternoon and this morning, probably in the dark of night. The molt remains in the tank, to show visitors what happened.

Spiny lobster (Panulirus interruptus) on the right and its molt. 7 September 2015 © Allison J. Gong
Spiny lobster (Panulirus interruptus) on the right and its molt on the left.
7 September 2015
© Allison J. Gong

Being encased in a rigid exoskeleton, all arthropods grow in stepwise fashion, increasing in size only during that brief period between when the old exoskeleton has been shed and the new one has hardened. Once they reach full adult size they may continue to molt yearly, but no longer grow. Fluffy's exoskeleton may be hard by now, and to the naked eye he doesn't look any larger than he was before. Then again, if he was already full-grown when he came here, I wouldn't expect him to grow much, if at all.

When crabs and lobsters molt, the old exoskeleton splits apart at the junction between the carapace and abdomen. The animal slips out backwards through the split, leaving the entire covering of its body behind. Before molting the lobster's epidermis would have resorbed some of the minerals from the old cuticle, and what is left behind is much thinner and more fragile than it was when the animal was wearing it.

Molted exoskeleton of a spiny lobster (Panulirus interruptus). 7 September 2015 © Allison J. Gong
Molted exoskeleton of a spiny lobster (Panulirus interruptus).
7 September 2015
© Allison J. Gong

In the photo above you can see the split between the carapace and abdomen. I think it's amazing how the legs, eye stalks, and antennae can slip out of the old cuticle without being broken or damaged. However, until the new exoskeleton has fully hardened the animal is vulnerable and usually hides out for a few days. Fluffy may not eat until tomorrow or the next day. One interesting note. A lobster's gills, being external structures, are covered by a thin layer of cuticle and are molted along with everything else. If you come across a recent crab molt, lift up the carapace and you might be able to see where the gills are located. How cool is that?

2

Now is not a good time to be a sea star in my care. Although to be honest, I doubt these animals would be better off in anybody else's care, either. And what's going on today isn't so much a series of unfortunate events as a trio of additional episodes in the two-year serial catastrophe that we call sea star wasting syndrome (SSWS).

Episode 1: My third Leptasterias star finally bit the dust today, a full week after the first one tore itself into pieces. Yesterday I was teaching all day and didn't have time to take pictures when I checked on things at the lab, but the star was intact. Today, not so much:

Leptasterias sp. star exploded due to SSWS. 4 September 2015 © Allison J. Gong
Leptasterias sp. star exploded due to SSWS.
4 September 2015
© Allison J. Gong

On Monday, four days ago, the star had a small lesion on the aboral surface of its central disc. It was crawling around and aside from the lesion appeared healthy. While this individual survived longer than the other two, the progression of SSWS from small lesion to total dismemberment is surprisingly rapid. I shouldn't be surprised, as I've watched SSWS take apparently healthy Pisaster ochraceus stars and turn them into piles of rotting disembodied arms in a single day. That was almost exactly two years ago. Maybe it's something about the Labor Day holiday.

Episode 2: Since I lost two of my bat stars (Patiria miniata) to SSWS back in July, I've been keeping an eye on the five that remain. They seemed to be doing fine until this week, when I noticed that one of them had developed a lesion. It was a very small superficial lesion on Monday but now it has grown both larger and deeper.

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

Here's a brief note about sea star anatomy. The small inter-radial clean-edged pale orange structure located at 6 o'clock is not a lesion. That is the animal's madreporite, the ossicle through which water passes in and out of the water vascular system. The madreporite of Patiria tends to be pretty conspicuous; in other species it can be more difficult to find.

The lesion is the larger, paler, fluffier bit that doesn't have clean edges. It's an open wound, and the white fluffy stuff is the star's soft tissue. Today the wound measures about 1 cm across its widest dimension:

Lesion on aboral surface of Patiria miniata. 4 September 2015 © Allison J. Gong
Lesion on aboral surface of Patiria miniata.
4 September 2015
© Allison J. Gong

I'll keep checking on this star and see how quickly the lesion grows.

Episode 3Scott and I have had to accept that we aren't having much luck growing up our tiny Pisaster stars. This afternoon we counted 16 of the 0.5mm orange dots that are juvenile stars. We consolidated 12 of them into a single jar and kept the other four in a bowl with a piece of mussel shell. We have failed to determine what it is they eat when they're this small, unless it's more than sheer luck that the four with the mussel shell haven't experienced any mortality in two weeks. And yes, we will continue to change the water in the jar and the bowl twice a week.

For broadcast spawners such as Pisaster ochraceus, which shed gametes into the water, reproductive success is all about numbers--numbers of spawning individuals in a population as well as numbers of gametes produced. In our experiment the numbers just weren't working in our favor: (1) we got usable quantities of gametes from only two females and two males; (2) fertilization success was pretty low for both crosses (Purple x Purple and Orange x Orange); (3) all embryos for the Orange x Orange cross died in the early developmental stages; and (4) settlement and metamorphosis success was low for the Purple x Purple cross survivors. And now we're down to 16 stars. By this time next week we may be down to zero stars, although those four on the mussel shell might still be hanging on.

We knew going in that the crux of the problem would be feeding the juveniles; I was reasonably certain that we'd be able to get through the larval stages successfully. And this is indeed what has been the case. Right now I feel more than a little disheartened even though the result we got (i.e., we can't get the damn things to eat once they metamorphose) is far from unexpected. Fortunately it will be months before our brood stock can be spawned again so I have lots of time to decide if it would be worthwhile to try the experiment again. I will need to come up with some new ideas of what to feed the juveniles.

To recap:  Way back in January I spawned some sea urchins. The resulting progeny are now almost 7.5 months old, counting from the day that they were zygotes. Once they metamorphosed and became established as post-larval urchins in June, I divided them into three feeding treatments:  the kelp Macrocystis pyrifera, the green alga Ulva sp., and a red coralline alga. Since then I've been counting and measuring them monthly, and today I completed the fourth data collection.

I could tell by looking at the bowls that the Macrocystis and Ulva urchins continue to grow much more quickly than the poor urchins stuck on the coralline diet. The Macrocystis urchins are, overall, bigger than the Ulva urchins, despite the qualitative observation that the Ulva urchins appear to be eating more. However, I am not monitoring the amount of food that is eaten by any of the urchins.

Test diameter of juvenile sea urchins (Strongylocentrotus purpuratus) as a function of diet. 2 September 2015. © Allison J. Gong
Test diameter of juvenile sea urchins (Strongylocentrotus purpuratus) as a function of diet.
2 September 2015.
© Allison J. Gong

In the past month I lost almost half of the coralline urchins; I'm down to six. Mortality for the other groups remains low. I think the Macrocystis and Ulva urchins have for the most part gotten big enough that, barring any unexpected disastrophe (yes, I made up that word), they shouldn't experience much mortality.

Population sizes of juvenile sea urchins (Strongylocentrotus purpuratus) as a function of diet. 2 September 2015. © Allison J. Gong
Population sizes of juvenile sea urchins (Strongylocentrotus purpuratus) as a function of diet.
2 September 2015.
© Allison J. Gong

In terms of color, I think the differences between the Macrocystis and Ulva diets have become more pronounced in the last month. Today I tried to photograph the two groups of urchins under the same lighting conditions, with mixed success. There's some variation within groups, of course, but overall the Macrocystis urchins have a more golden color on both the test and the spines. . .

Juvenile sea urchins (Strongylocentrotus purpuratus) eating the kelp Macrocystis pyrifera. 2 September 2015. © Allison J. Gong
Juvenile sea urchins (Strongylocentrotus purpuratus) eating the kelp Macrocystis pyrifera.
2 September 2015
© Allison J. Gong

. . . whereas the Ulva urchins have more purple coloration:

Juvenile sea urchins (Strongylocentrotus purpuratus) eating the green alga Ulva sp. 2 September 2015 © Allison J. Gong
Juvenile sea urchins (Strongylocentrotus purpuratus) eating the green alga Ulva sp.
2 September 2015
© Allison J. Gong

And, just to make sure that I hadn't inadvertently biased the light in favor of one group at the expense of the other, I manhandled all of the urchins to one side of their respective bowls and took a picture of the two bowls side by side. Let me tell you, it was like herding cats. I'd get one group all bunched together then start working on the other, and the first ones would immediately begin wandering away from where I'd put them. This is the best shot I managed to get. Without reading the caption, you can still figure out which group is which, right?

Juvenile sea urchins (Strongylocentrotus purpuratus) feeding on Macrocystis (left) and Ulva (right). 2 September 2015 © Allison J. Gong
Juvenile sea urchins (Strongylocentrotus purpuratus) feeding on Macrocystis (left) and Ulva (right).
2 September 2015
© Allison J. Gong

We're coming into the time of year when it might be difficult obtaining food for these urchins on a regular basis. Everybody may have to go on a diet for a few months. As long as I can get my hands on both Ulva and Macrocystis I'll keep feeding them, and when I run out of one food the other group will have to fast also. I think they're well enough established by now that not having unlimited food won't do much harm.

I just had another thought. I could put the Ulva and Macrocystis urchins back on coralline rocks and see how they do over the winter. Something to think about.

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