Featured Creature Friday: The Punishing Pistol Shrimp

I don’t know about any of you, but I don’t give shrimp much thought. Sure, they’re an essential part of ocean ecosystems, but I don’t even enjoy eating them, and I certainly don’t want them anywhere near my cocktails, so for the most part they’re not even on my radar, so to speak. If I’m thinking about the oceans I’m usually pondering the terrifying threat of jellyfish, so shrimp don’t even rate a mention. This was clearly an oversight on my part; I’ve been learning lately about a few sorts of shrimp that are packing some deadly firepower. (They may be useful allies when the jellyfish come for us, let us all take note.)

Still from BBC's "Invisible World"

Still from BBC’s “Invisible World”

The Alpheidae are a family of shrimp commonly known as “snapping shrimp,” and the Pistol Shrimp is perhaps the family’s most famous member. It’s a tiny animal, only a few inches long, but it’s packing some serious firepower in the form of a claw with a specialized snapping mechanism that allows it to “shoot” a high-velocity air bubble through the water. That might not sound so intimidating, coming from a tiny shrimp, but trust me when I tell you it’s seriously bad-ass. The Pistol Shrimp’s claw has a jointed “hammer” mechanism which snaps shut with such force that it vaporizes the water in front of it, forming a bubble. The bubble doesn’t go far, only about 4 centimeters, but it travels at speeds up to 60 miles per hour, generating enough force to kill fish, break glass, and knock well-armored opponents on their proverbial asses. The bubble’s real power, though, is in its collapse; in a process known as cavitation, the bubble essentially implodes under the pressure of the water around it, and that implosion not only produces sonoluminescence — a short burst of light which in the Pistol Shrimp’s case is invisible to the human eye — but also generates temperatures nearly as hot as the surface of the sun. The Pistol Shrimp was the first animal that was ever demonstrated to produce sonoluminescence (in a future featured creature we’ll take a look at the Mantis Shrimp — not actually a shrimp — which packs a similar punch and has also been found to generate sonoluminescence).

Still from BBC's "Invisible World"

Still from BBC’s “Invisible World”

The noise of the Pistol Shrimp’s bubble collapsing is brief, less than a millisecond, but the sound produced can reach a staggering 218 decibels; when there are a lot of them in one place, the cacophony is loud enough to interfere with underwater communications and submarine sonar. (The voiceover narration on this video is completely terrible, but it gives you a great sense of exactly how noisy the ocean really is — skip to about 6:00 for some great audio — and snapping shrimp are a major contributor to the noise.)

The Pistol Shrimp uses its awesome firepower to stun, disable, or even outright kill its prey, which it usually hunts from the comfort of its own burrow; it detects passing meals with its antennae, stuns its meal with a bubble blast, and then drags it into the burrow to devour. Lazy bastard. It can also use its pistol-claw in self defense and to communicate with its fellow shrimp. Not quite cool enough for you? Okay, how about this: if a Pistol Shrimp’s gun-claw is torn off, not only will it grow a new limb to replace the missing one, its other claw — which is typically smaller, while its shooting arm is half the size of its body — will grow to become its new shooting hand. It can grow back missing parts and it’s ambidextrous. If you don’t seriously love this shrimp right now, I can only assume it’s because you’re jealous.


BBC Weird Nature

Some varieties of Pistol Shrimp have also learned to live cooperatively with another species, which is more than I can even say for me and my dog. Pistol Shrimp build their own burrows, but they’ve been known to share their space with goby fish, which have superior eyesight and act like watchdogs for the shrimp. The fish alerts the shrimp to danger, and then they both retreat into the burrow together. Presumably they also snuggle. I’m guessing the fish is the little spoon.


BBC Invisible Worlds

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Featured Creature Friday: The Humble Hermit Crab

It seems only appropriate that today’s featured creature should be one that, at first glance, seems a little boring. Hermit crabs are pretty common animals — there are 1100 different species and many of them are kept as pets. Of course, as pets, they’re about on par with seamonkeys or beta fish, the kind of pet that people impulse buy for a couple bucks and expect to be dead within a week. (With proper care, of course, these sorts of animals can live a long time — some species of hermit crabs, for instance, have been known to live over 20 years in captivity.)

Naked hermit crabs kind of look like what would happen if H.R. Giger had been in charge of creating Hello Kitty. (Photo by Arnstein Rønning, 2011, by way of Wikimedia. Used under Creative Commons license.)

Hermit crabs just don’t get a lot of credit for being complex animals with intricate social — yeah, they’re not very hermit-y — behaviors. And frankly, I don’t think we’re appreciative enough of the hermit crab’s particular form of body armor/performance art; unlike true crabs, hermit crabs have no shell of their own, and instead acquire or improvise a suitable home. You’ll find them living in snail shells, stones, driftwood, broken bottles, crab shells, glass shells, and even, apparently, Legos.

Without a shell, they’re vulnerable and also a little funny-looking when they’re naked, just like people. Which is why they armor themselves with the detritus of the sea floor. Basically, they’re like the Iron Man of the sea, if Iron Man was kind of timid and spent all of his time eating tiny things in the ocean.

Which he doesn’t. Because he’s Iron Man. And that’s neither here nor there.

In cases of shell shortage, hermit crabs will fight over shells the same way humans will fight for a decent neighborhood and a jacuzzi bathtub. But give them shells in abundance and they’re practically socialists, as this article in Scientific American explains:

When a lone crab encountered one of the beautiful new shells, it immediately inspected the shelter with its legs and antennae and scooted out of its current home to try on the new shelter for size. If the new shell was a good fit, the crab claimed it. Classic hermit crab behavior. But if the new shell was too big, the crab did not scuttle away disappointed—instead, it stood by its discovery for anywhere between 15 minutes and 8 hours, waiting. This was unusual. Eventually other crabs showed up, each one trying on the shell. If the shell was also too big for the newcomers, they hung around too, sometimes forming groups as large as 20. The crabs did not gather in a random arrangement, however. Rather, they clamped onto one another in a conga line stretching from the largest to smallest animal—a behavior the biologists dubbed “piggybacking.”

I guess that it’s a bit like when you’re a kid and all you get to wear is your siblings’ hand-me-downs (so speaks the youngest child of the family…), but the hermit crabs at least seem happy about it. And sometimes intensely competitive. Here’s a sweet video from Blue Planet with a terrifyingly huge snail, plus some hermit crab combat. The first rule of Fight Club is, you don’t talk about Fight Club.

Speaking of hermit crabs, did you know that coconut crabs are also sort of a hermit crab? In addition, they’re the largest terrestrial arthropod in the world (that means land-dwelling creepy-as-shit crab-thing). They can and do climb trees, live for decades, and have pincers so powerful they can crack coconuts. When the mommy crab and daddy crab love each other and decide to have a family, the female crab releases her eggs into the ocean, where the young ones start out as plankton. As juveniles they do the usual hermit crab thing and find random shells to live in, then when they get older and toughen up a bit they get by with just a thick sort of leathery exoskeleton and put away childish things like shells. Eventually crawl their way back onto land. Despite being the sort of creature you might imagine dwelling in the sea, adult coconut crabs actually drown if they’re left in the water, and so they generally prefer to dwell in your nightmares.

OH MY GOD HOW ARE YOU SO ENORMOUS AND WHY DO I SEE YOUR TERRIFYING PINCERS EVERY TIME I CLOSE MY EYES.

Here There Be Sea Monsters (And Also Snuggly Little Otters)

As you may recall, I am in general not always a big fan of creatures of the sea. Jellyfish, for instance, are at the top of my personal Threatdown list. But there’s more to an aquarium than jellyfish — and the lure of otters is too strong to resist — so today some family members and I took a field trip to the Living Planet Aquarium in Sandy, Utah. I haven’t had much of a chance to practice my low-light and zoo-ish photography, so I brought my camera along (with apologies to my awesome long-suffering sister-in-law, who has to put up with this same nonsense from her husband all the time) and managed to get a few shots I quite liked.

I want to get one of these frogs and carry it around on my shoulder at all times. It looks like it's really wise and might enjoy advising me on how best to conduct my business.

These Lion Fish are actually venomous, but they were also pretty good about showing off for my camera, so I guess they're not just straight-up jerks.

The aquarium itself was a bit of a disappointment — their interpretive signs left much to be desired, and a great many of the animals’ habitats were both small and overcrowded, with some of the views obstructed by slightly grimy tanks — but it was about what I expected from an aquarium of its size, especially considering that looking at the building from the outside it appears as if they converted an old K-Mart or something. I have to applaud them for having done as much as they have with the space they’re working with, but it’s clearly not the best possible situation. Luckily, a brand new aquarium building is in the works, with 130,000 square feet in Draper and what looks like a much more purpose-built and animal-hospitable building. Currently they’re planning to break ground this summer with a possible opening as early as spring 2013. I can’t wait to give the new place a try when they’ve upgraded their facilities. For now, if you’ve been to SeaWorld it’s not going to even remotely impress you, but if your aquarium experience begins and ends at the pick-your-own-crustacean tank at Red Lobster, then you’d probably find all of these exhibits incredibly diverting and educational.

They had several kinds of sea horses, which was awesome, but the leafy sea dragons were apparently hiding -- or just so good with their marvelous pretending-to-be-a-bit-of-plant-matter disguise that I couldn't spot them -- which was super-sad.

These piranhas were particularly super-awesome... those gold-colored flecks are just incredible. I wouldn't want to take a swim with them, though.

OMG OTTERS.

In case you've ever wondered what an otter looks like while it's pooping, this is the answer. YOU'RE WELCOME. It occurs to me that this always seems to be the pose that taxidermists choose to put stuffed otters in, which makes me wonder whether that's some sort of bathroom-related inside joke among taxidermists all over the world.

Here is a photo of a jellyfish. Jellyfish thing. I don't even know. I'm just showing you this so that you can identify the enemy.

Here is the obligatory NEMO! moment. Now that we've gotten that over with, we can move on to the serious biznis.

Like for instance this eel. Eel-thing? This is definitely serious. I couldn't find a sign saying what sort of eel this is, but I'd guess it's a giant moray. And thanks to Google I've discovered that eels gape their mouths open in this very threatening-looking fashion to help them keep water flowing through their gills and help them breathe. Rad. Also rad? That frilly corral-looking thing at the bottom left is a wobbegon, which in this case seems to mean a shark disguised as furniture, and it was chilling out with a huge eel so it had instant street cred. Tank cred?

This lobster is apparently over 45 years old. That kind of depressed me for reasons I can't really explain. Also, he's totally pretty and blue, which made him seem rather decent for being a cockroach of the sea.

I'm not really that into fish, but I did like the frogs. They were incredibly colorful and also adorable.

And speaking of adorable, here are a couple of Axolotls. I had to Google that to make sure I was spelling it right. What would I do without Google? Probably curl up in the corner and cry.

I don't know what this is, which is why I'm calling it a "gecko-y thing maybe" like that is its official taxonomical classification. My brother says it's a newt, which is probably the case, but "newt-y thing" doesn't have quite the same ring to it.

I was surprised at how well some of these photos came out, considering my camera is not exactly the latest in DSLR technology and it was really quite dark in there. This last photo, of a sleeping green tree snake, is one of my favorites from the day. (That first frog shot is definitely the other top pick.)

I’ve been having a great time lately finding occasions to visit some of the local attractions here in the greater Salt Lake City area… it’s sort of fun to make yourself be a tourist in your native land. Keep an eye out for more posts and photos from around town as I continue to endeavor to get myself out of the house….

Featured Creature Friday: The Dapper Dresser Crab

You can ask anyone who knows me, and they will tell you the truth: I know nothing about fashion. That’s why I’ve been looking to the experts for tips. No, I haven’t been watching a Project Runway marathon, and I still have no intention of taking my mom’s suggestion that I should go on What Not To Wear. (Thanks mom.) Instead, I’ve been reading up on dresser crabs.

I'm not really sure if the pearls are the right look for you, but they are a classic.

Don’t laugh. You don’t know a thing about accessorizing until you’ve seen a dresser crab (also known as a decorator crab) carefully select the right look for any occasion. But this isn’t just about fabulousness for them: it’s a matter of life and death. In order to defend themselves against predators, these crabs actually attach bits and bobs found on the ocean floor to the velcro-esque surfaces of their bodies, and then freeze to blend in with their surroundings when they feel there’s danger.

The crabs in the video, of course, are wearing the latest in crab fashion, but normally (when BBC camera crews and their obviously twisted senses of humor aren’t involved) dresser crabs use more common items found on the sea floor. After all, it’s the ocean, and they don’t have H&M or Abercrombie stores down there. (Yet.) They can’t just go pick up a nice frock or a pair of skinny jeans.

Their typical attire, however, is infinitely more bad-ass. Dresser crabs will stick anemones (which have stinging tentacles) or poisonous seawood to their backs. Then they’re not only sporting the latest fashion, but also a formidable defense against any animals foolish enough to tangle with them. I’m not sure why anybody would tangle with them, though. Dresser crab hangouts must be like the awesome drag reviews of the sea. And frankly, with all the jellyfish in there, I reckon the sea can use all the awesome it can get.

Featured Creature Friday: The Fabulous Fossil Sharks

I kind of have a thing for “living fossils.” Maybe it’s just because I watched Jurassic Park a few too many times in my youth, but I love the idea that there’s so much of our planet’s natural history still visible to us today, from the deep and fascinating layers of geology to the life forms that haven’t changed much in the last few million years. Some of those animals are so bizarre that they’re almost difficult to comprehend: they seem like things that couldn’t possibly exist in our world. Maybe they think the same about us.

photo from National Geographic / Getty

One of those creatures is the frilled shark, which is notable not only for its overwhelming creepiness but also because it’s one of those deep-sea swimmers that we rarely see. They’re something of a reminder to us of just how much we don’t know about our planet and the other creatures that live here. And the fossil record on these animals goes back 80 million years. 80 million years. Let that sink in for a moment while you watch this video of an extremely rare live specimen that was found off the coast of Japan:

(It’s worth noting that this shark was way outside of its habitat long before it was captured and taken to the marine park, so while I’m not a big fan of the “We have found a rare animal, let us place it in captivity!” mentality, this shark was likely already dying before it was captured.)

We don’t really know that much about frilled sharks, because of the depths at which they usually reside (thousands of feet below the surface). We do know they eat things like squid and other sharks. Their teeth are three-pronged and their fixed upper jaws (unlike the hinged ones of modern sharks) give some idea of exactly how far back the genetic heritage goes on these sharks.

photo from National Geographic / Getty

As a bonus, because personally I believe that one creepy shark simply isn’t enough, here are a few more. This is a Goblin Shark:

This thing has a mouth that practically acts independent of its body; check out how the mouth works when the shark bites into the diver’s suit (presumably no divers were harmed in the making of this documentary :D), and then how the mouth returns to its original configuration once the shark lets go. This shark is like the transformer of the sea. Or maybe I ought to compare it to Alien. Whatever, it’s freaking awesome.

My favorite freaky prehistoric shark video, however, is this one of the Six-Gilled Shark, filmed at a depth of 3300 feet:

It’s not the world’s most exciting video, and the Six-Gilled Shark doesn’t look all that different from the sharks we’re more familiar with, but this thing is massive, at about 18 feet long. (There are larger sharks, like the Basking Shark, but this one’s pretty impressive anyway.) The best part of the video is the audio though, so make sure you watch it with the sound on so you can listen to some marine scientists having a joygasm over the sighting.