Christie Wilcox describes a terrible experiment. Investigators were mystified by an area around a Pacific island that was empty of lobsters, so they dumped a bunch of lobsters there to see what happened. And then…
“Visibility was great that day, and virtually the entire sea bottom started to move,” he said.
That movement was countless whelks. They started to climb onto the newcomers, sticking to their legs. “I didn’t know then, but they’d started to suck them alive, basically. It was like a horror movie,” Barkai said. “It actually was a bit frightening to watch.” The lobsters simply didn’t know how to respond. They were outnumbered and overwhelmed.
“To my horror, in about 30, 40 minutes, all the lobsters were killed.”
Barkai managed to bring two whelk-coated lobsters back to the surface to show the crew—which is when the first photo in this piece was shot. The bewilderment on his face says everything. On the ship, they carefully pulled the whelks off—over 300 per lobster. “When we removed the whelks from the lobsters, they were empty shells. There was no meat left at all whatsoever. They were simply empty shells,” he recalled. “Basically the only thing that kept them together was the whelks, so the moment we removed the whelks, the lobsters just fell apart.”
But perhaps the most awful part was seeing up close how the whelks had done the lobsters in. They had penetrated every single soft tissue that they could find with their tubular mouthparts—the lobsters’ eyes, joints, anywhere with even a little give. “You could see these very long pipes coming in from the inside of the lobster,” Barkai explained. The poor lobsters—”they didn’t have a chance.”
So, to oppose the lobsters, one must be a whelk. Which is interesting, because the lobster-devouring whelks don’t seem to exhibit much in the way of hierarchical behavior, and do have some anti-lobsterian social behaviors.
Pity the male of the marine whelk, Solenosteira macrospira. He does all the work of raising the young, from egg-laying to hatching — even though few of the baby snails are his own.
The surprising new finding by researchers at the University of California, Davis, puts S. macrospira in a small club of reproductive outliers characterized by male-only child care. Throw in extensive promiscuity and sibling cannibalism, and the species has one of the most extreme life histories in the animal kingdom.
Now that I’ve stuck the knife in, let’s twist it a bit.
“The promiscuity in the female snails is extraordinary,” Kamel said, noting that some females mate with as many as a dozen different males.
Whelks: the lobster’s worst nightmare. I’ve been saying for years you’ve got to admire a good mollusc.
A useful reminder that for all people accuse arthropods of being creepy, it’s predatory gastropods that are horror creatures.
Apparently male-only child care also occurs in some insects, and it is always associated with promiscuity. Basically it serves as a way for males to distinguish themselves from competitors. Even if some eggs aren’t their own, they attract more females by showing off what capable care their offspring would receive.
Yes it’s horrible.
Now then: Are whelks good eatin’?
Bulots !!
Salade d’Escargots de Mer « buccin » !
Burp.
This may decide where I go for dinner tonight… problem is homard is not typically available without pre-ordering…
Yes, whelks are supposed to be delicious. I’ve never had one, and apparently their popularity has been in decline for a while.
sparks@2, “Welks”, technically, refer to various different critters, albeit apparently all sea snails. The ones I consume — see @3 — are good eating. I presume the ones who eat the lobsters in the OP are (closely?) related to the ones I eat, as both them and I live in the Mediterranean area. I also presume the bulots I eat are “local”, but am uncertain… (The homard probably are not “local”?)
What a bizarre experimental protocol. “Let’s just introduce a species to a new environment to see what happens!”
Maybe we could introduce Mr. Peterson to the whelks?
Yeah, what Ed @7 said. We need an experiment in which we dump Jordan Peterson, and maybe his daughter for good measure, into that same Pacific lagoon and then we see what happens.
6 @ Holms:
It wasn’t a new environment. Only 20 years previous, there had been an abundant population of lobsters there. Overharvesting of lobsters there shifted the balance, along with the whelks there being protected by a bryozoan coating their shells, thus reversing the predator-prey relationship between lobsters and whelks. The other nearby island, Marcus, was crawling with lobsters and virtually nothing else but kelp and sponges, since the lobsters were eating everything. But once they’d been so drastically reduced at Malga, the whelks took over and wiped them out and they couldn’t come back. Very bizarre situation. Very interesting article.
What shocked me was the number of lobsters in the experiment. I figured a few dozen, maybe a hundred, but they dumped a thousand lobsters in, all dead in about 30 minutes. So it must’ve indeed looked like a horror movie.
That’s a hardcore mollusc.
I trust that the whelks wrote a nice letter to the scientists thanking them for providing such a nice, unexpected lobster feast.
Je suis whelk.
There’s more about whelks here.
I read this as a subtle allusion to PV’s other posts on the Trump White House: large predator arrives in a space that seems ripe for exploitation; the whelks attack little by little. Distressed lobster tweets a bit and dies; we now return to our regularly scheduled degraded ecosystem programming.
Maybe I just try to see the bright side of things.
Snails can be vicious. I use a species called “assassin snails” to keep the common garden snail population at bay in my planted aquarium. Once they get acclimated to their new environment, they just go to town; injecting one snail after the other with a paralyzing toxin and then consuming them. After a few days, even the worst garden snail infestation is gone. Nasty little things, but useful.
@11–
“So long and thanks for all the lobster.”
But do they only eat beef? Do they only drink club soda? Inquiring minds wish to know.
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There are yellow submarines: http://www.abc.net.au/news/2018-08-31/crown-of-thorns-starfish-killing-robot-great-barrier-reef-qld/10183072
A really immoral experiment.
“She swallowed the whelks to eat the lobster, but I don’t know why she swallowed the lobster.”
At the risk of stating the obvious. What would Jordan Peterson say?
It is quite the horror show of a poorly thought out experiment. The findings that resulted are very interesting, but even the person who did the lobster massacre realizes that it was a terrible idea.
I also questioned the claim that the males somehow lay eggs, because there is no such thing as egg laying males of any species AFAIK. I reading of the second link cleared up the basic biology, but I am a little surprised to see such an obvious error made multiples times in the link, and then repeated on a biology blog.
I wonder if males with bryozoa on their shells are preferred egg laying sites?
Why not share your ideas for a better method? As a first attempt, seemed entirely reasonable to me. He even started with standard exclusion experiments.
If you’re thinking it was horrible because what happened to the lobsters?
There was no way to know before conducting the experiment
It’s still an entirely valid method.
Again, how could this have been done differently in order to gather data to either support or reject the idea that the snails were excluding the lobsters? That’s a point worth discussing.
I often ran into issues with my own experimental designs sometimes where I really wanted to look at alternatives that would impact the subjects of the experiments a bit less. Often, even with an entire department at hand to make suggestions, there just weren’t any better alternatives anyone could think of in order to complete the experiment.
I also questioned the claim that the males somehow lay eggs
in addition to what you noted with this specific case, most snails are hermaphrodites, and they ALL lay eggs.
some even self fertilize.
blockquote fail.
I don’t think the article is meant to say that the males lay eggs, but that they begin looking after them from the moment they are laid. And no, most snails are not hermaphrodites. The terrestrial snails are; but the largest group are the Caenogastropoda, including many different sea snails like whelks, and they almost all have separate males and females.
Thanks for the information Monad! I thought the claim as quoted by PZ
was perhaps a misquote or a typo, but it is repeated twice in the linked article before it clarifies that the females use the males shell as a suitable egg laying substrate, and their environment lacks rocks or other surfaces that are typically used by other marine snails.
Even among the hermaphroditic types of snails, one typically does the egglaying and the other does the fertilizing. Love darts are a strange snail mating process. I know there are also marine species that are males when small and mobile, but turn female when they become large and stationary.
Ichthyic
A better method would have been to check for predators with a single crate of lobsters and a camera, rather than just randomly dumping 1000 animals into a foreign environment. The researcher himself admits he did not think it through very well, and was horrified at what he had done to the lobsters. I do indeed have an issue with human beings having a callous disregard and causing mass death to wild animals that were just going about their lives, even if they were just lobsters.
it wasn’t random, and it wasn’t a foreign environment (lobsters were in this area historically, and quite recently).
“A better method would have been to check for predators with a single crate of lobsters and a camera”
Then you run into localized area effects, and have to repeat the localized experiment in many different areas besides, resulting in similar loss of numbers. I agree that would be a more controlled experiment however, even if in the end the number of casualties would be similar. In the end, you’d STILL need hundreds of lobsters for decent replication, but you’d get better data for sure.
frankly, I see no way around it, and your suggestions, while an improvement on the ability to better control the data collection, would in the end still require lobsters to be transferred from one local habitat to another. Field experiments are NOT easy, and yes, most of us DO want to figure out ways to have minimal impacts, but also realize the research will generate information that actually helps the animals we study in the long run.
Did you click through and read the link? The question was "Why aren't there any lobsters in this small localized area anymore, when the nearby island is crawling with them?" Barring any obvious environmental reasons, logic would suggest an abundance of predators as the most probable difference. Since they could clearly observe the entire area to know that all the lobsters were eaten within 30 to 40 minutes, a single crate of lobsters would have provided sufficient evidence of the whelks, with far less effort.
Huh, that’s a new tech glitch. I have no idea why my comment is in red unless I put in a line break after the blockquote.
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Tethys, looking at the source, you’ve apparently inadvertently used the <code> tag, resulting in fixed-width font in red due to this site’s rendering of it. No biggie.
Whelk, actually…
Why do I think this we be a scene in the next David Cronenberg movie.
Yum!
https://cooking.nytimes.com/recipes/1014417-whelks-with-parsley-and-garlic-butter
The power of Cheeeerist (and seafood) compels me … to try them!
@Tethys:
I think I actually agree that seeing what happened with a few, or even one, would have been a reasonable first attempt, and given what Barkai says, he would agree with this too. The article does mention that they put lobsters in cages in the water, but I guess they had mesh too small for the whelks, or maybe they weren’t on the seafloor.
Still, this is a case of hindsight. I don’t think it’s immediately obvious that the population of whelks had grown quite so large, or that something as small as whelks could and would so completely overwhelm something as large as a lobster, even en masse, so quickly. They might have been thinking that there was something repulsive to lobsters, or even toxic, and they would record the statistical retreat of the lobsters from the area over time. Or maybe there was something that interfered with lobster reproduction, which would take a generation to be recorded and demonstrated.
The symbiotic relationship with the bryozoa is fascinating, as is the adaptatations of the whelks to an environment that lacks suitable egg-laying hardgrounds. The sediments of the seafloor host all kinds of strange carnivorous animals, and whelks have been around for a very long time. I expect that normally the lobsters and whelks are in direct competition, and act as a balance on each others populations, but overfishing the lobsters allowed a population of whelks with bryozoa to establish itself in the available habitat.
According to wiki, the whelk locate prey using chemoreceptors. I don’t know why Barkai decided to do such a large first release , but the fact that his test subjects had 100% mortality within the hour is a compelling bit of evidence that starting with 1000 lobsters was scientific overkill.
damn you tatatypos