Squidnappers and Octopossies: the Wild Wild Wet

Okay, that title might have been a bit too much, but science puns are fun! Science! Yay?

Anyways, the point is that I went on a night snorkel last night and it was AWESOME. Little tiny blinky lights in the seagrass, the moon full and high above the water, the reef dark and looming ahead of us… We (three of us, me, Molly, and Ellen) swam out into the darkness with our little dive torches, ready to explore the now-familiar reef in front of the LCRC in a completely unfamiliar light (or lack thereof, as it were).

It’s a different place after dark. Coral polyps compete with anemones (invisible or hidden during the day) for the title of “wiggliest sessile animal in these parts here’bouts” and giant spiny lobsters assure one another that the reef is certainly not big enough for all of them. Meanwhile, Billy the Squid is sneaking up from behind with glowing spots and tentacles drawn:

Image

As the parrotfishes all slept in their warm mucus blankies, the predators were on the prowl, thieving and snatching and generally causing very quiet but very effective mayhem on anything unlucky enough to get caught out after the curfew set by the sun. This octopus is bank robber #1 out on this reef, reaching tentacles into reef hidey-holes and swapping disguises to blend in with the background and escape notice from the good townsfolk of the reef.

IMG_9406The water is dark and the visibility is limited- but the rewards are great for those who dare to venture forth to the frontier of night. Invertebrates galore, bioluminescence, and all kinds of stealthy hunters and skittish prey… never a dull time out in the wild, wild wet.

 

 

I’m a Pebble, I Swear

Remember that scorpionfish from a few days ago? Well, it’s certainly not the only thing hiding in plain sight in the rocks and corals and sea grasses around here.

I’m sure you’ve seen pictures of flounders before… but I gotta tell you, they’re harder to find in real life unless you scare one up out of the sand. Can’t you just see him willing you not to notice that he isn’t a patch of sand? Willing himself actually to become the sand? So zen’d out into his environment… “Become the sand. Feel your graininess and be one with the sand…”

Image

 

Here’s another sneaky little guy- a box crab. I love these for so many reasons. Crabs, first of all, are generally awesome. Their eyeballs are super cool, their legs are fun and tickly, and they have a general attitude that appeals to me on cranky days. Box crabs are special because they fold up into perfect little packages, claws and legs and all, and will themselves into pebble-dom, which of course appeals to me as a Rockapella (my a capella group at Dartmouth calls its freshmen “Pebbles” because they’re baby Rocks, get it?) and as a lover and collector of smooth stones and general cute things. 

Image

Imagine the amount of evolutionary pressure these cryptic little guys must be under (from batfish, stingrays, sharks, and all kinds of other predators) to evolve to look exactly like the stone and sand on which they live. It’s incredible, and incredible fun to solve the eyeball-puzzles they present out in the water! 

P.S. Hi Rockapellas!

I Like Invertebrates

Don’t get me wrong; I like fish too. But there’s something about the inverts of the sea that fascinate me. 

Take squids, for example. Cephalopods, they are over-developed mollusks (yeah, like snails and slugs and clams, only awesome-er) and are usually predatory. They swim “backwards,” using jet propulsion to push themselves through the water, tentacles trailing behind them. And their eyes are awesome. 

ImageThat’s not to discount the worms, though- these guys, segmented worms or annelids known as “fireworms” due to their stingy white side bristles, resemble strips of bacon when they swim or crawl across the sand and coral. 

Image

Inverts are so interesting- so many different forms and colors and weirdo ways of living. Expect more mollusks and crustaceans in the coming days! 

We’ve got another dive (actually, two) tomorrow, but the camera won’t go with me yet. Still making sure I’ve fully got my bearings and my buoyancy underwater before I add more distractions. But maybe tomorrow I’ll post some pictures from my night snorkel, to commence directly after this blog ends… LIKE NOW.

 

Slow and Steady Finally Shows Up

Remember all that running around on dark beaches that we did back in Santa Rosa at Playa Naranjo, looking desperately for nesting or hatching turtles? Well, I do. A total of four sleepless hours without moon, just red flashlights searching the jaguar-infested sand for little baby turtles… we saw lots of interesting crabs, but not much else.

But today, the turtles finally found us. Or at least this one did:

Image

He came swimming in over the reef, straight toward Seth, who was very pleased with his find, and Jill, who could not contain the awesomeness:

Image

Not sure why he was in so close to shore, but I’m glad he came by for a visit. I’ve loved sea turtles since I was little, on the beach in Hawaii.

This one was a new species for me: a hawksbill turtle, Eretmochelys imbricate. These turtles aren’t herbivorous like the Chelonia mydas (green sea turtles) that I know from Hawaii, but prefer to eat reef sponges. Since the coral’s taken such a hit from disease and acidification of the oceans, sponges have proliferated along this reef- might that be beneficial for the CITES-listed, once-hunted, critically endangered Hawksbill?

All in all, a very beautiful and successful day at the beach- we had our first dive (camera-less, sorry, didn’t want to have to think about that plus all the gear on my first dive in two years) and everyone checked out with skills, and we made plans for a night snorkel tomorrow after dinner! We’ll be figuring out research projects to start on tomorrow as well- post any reef questions or comments that we might be able to investigate in the comments!

Life is pretty sweet. The adventure continues.

Image

Goodbye, Costa Rica… HELLO LITTLE CAYMAN

We left La Selva two days ago (…sorry… I’m running just a little behind…) and took off for Miami, Grand Cayman, and then Little Cayman Island, where we arrived yesterday. The view of the reef flying in was incredible- Little Cayman has a barrier reef almost all the way around, and the color of the water changes dramatically from reef to nearly bottomless drop-off. The wall-diving here is supposed to be spectacular, but for today we stuck to snorkeling. 

We walked right out of the dining room from breakfast into the waves, taking a several-yard detour to snag wetsuits and fins and snorkels.

Image

The reef right in front of the Little Cayman Research Center, where we’ll be staying for the next few weeks, is simply incredible snorkeling. And Dad got me an underwater housing for my camera for Christmas- I don’t know if I’ve ever been as excited for a Christmas present put to use! Thanks Dad!

A few of the creatures we saw our very first few hours in the water:

This is a scorpionfish- I got lucky and spotted it on the seafloor next to a rock, I think because it was breathing and I saw its gills move. They’re quite venomous if you get pricked with their dorsal spines- like all the snakes from previous posts, no touchie!

Image

This one’s a Southern Stingray, one of the critters that makes the Caymans famous (the biodiversity here is huge, but the stingrays are pretty charismatic and like to be hand-fed, so snorkel tours go out of Grand Cayman to pat them all the time). 

Image

This Queen Conch, probably 18 inches from front to back, was presumably sifting through the sand to find food… while other mollusks and algae and tiny fishes colonized its beautiful shell. The wiggly reddish thing is a fire worm- a very good and painful reason not to dig around in the sand with bare hands.

Image

Tomorrow, we go on our first check-out dive (just to make sure everyone’s skills are up to par). Maybe in the afternoon when we get back, I’ll go looking for the 6-foot nurse shark that is supposed to hang out in the grass off of one of the boat moorings. Maybe I’ll get started thinking of research project ideas… hopefully ones that involve octopuses or pufferfish or nudibranchs or other cool stuff! 

Life could definitely be harder… 

Image

Expect more underwater photos, and hopefully some more natural history of the islands, coming up soon!

Night Life, Party Time

College kids are known for their late nights- procrastinated papers, raucous parties, frats, beer pong… well, our FSP does involve the occasional game of ping-pong on the folding table outside the researcher’s lounge, some late-night paper revisions (though it would be essentially impossible to procrastinate here), and, well, bio-nerd’s dream parties: night walks through the jungle.

La Selva is known for great birding, and to the FSP program is known as a great place to take night walks. The paths are wide and clear, and there’s always something interesting to see, whether it be an ocelot, an armadillo, a bat, or the little glass frog who sits on her eggs by the bridge. But if we only looked down on our nighttime excursions (party, woo!) we’d miss out on some of the most impressive sights.

Those who know me will know all about my passion for owls- silent fliers, possessed of awesome eyes and wicked eyebrows, sharp hearing, powerful wings… owls are pretty sweet. So far in Costa Rica I haven’t managed to get any good pictures, but I’ve been surprised a few times by a sudden rush of air over my head followed by a ghostly set of wings.

But another bird might be overtaking (or at least coming close to) my favorite avian predators- the Great Potoo, a tropical bird that perches during the day on dead trees, sitting perfectly still and pretending to be a dead branch. During the night, this fairly large bird (about  regular owl-sized, actually) shakes out its wings and yawns its massive beak before taking off into the sky and hunting down some big flying night bugs and sometimes even bats. (Can you imagine?)

As Tommy commented in a previous post, they have one of the most interesting and unsettling calls in the jungle- listen to the Cornell bird lab’s recording and imagine hearing that from out of the jungle as you walk alone through the dark:

http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=222936

Here’s my best Potoo picture- this one surprised me on the bridge over the river, and hung out for a few minutes to be admired.

Image

These next guys are some members of the nightjar family, either nightjars or possibly pauraques- I spotted their eyeshine with my headlamp on the ground right outside of our cabin, and had to check them out. They didn’t seem to care about my approach at all until they took wing in unison, buzzed my head, and set back down to wait for more insect prey on the ground nearby. You never know about those tricky birds… they could be anywhere.

Image

I probably ought to go to bed earlier than I do… but you know college kids, can’t miss out on that night life! 

Everyone Gets Defensive Sometimes

Animals displaying bright coloration and patterning to warn away predators are known as “aposematic,” and include things like coral snakes, skunks, and poison dart frogs (Dendrobatidae). This “blue jeans frog” is bright red and blue as a warning to potential predators that it is very nasty-tasting and/or dangerous to their health… but doesn’t lend them any stealth abilities for avoiding curious and camera-laden humans.

Image

Other fun facts about these frogs: they lay eggs in the leaf litter, fertilize them, allow them to hatch, and then carry the tadpoles on their backs high into the canopy, to deposit them in tiny pools of water caught in bromeliads. The mother will return to feed them every day until they are big enough to grow legs and leave the pools, somehow remembering each tadpole’s location, and providing them with the chemicals in their foods that they will need to retain their parents’ defensive poison.

Another type of animal defense involves not advertisement of unpalatability but simple hiding-in-plain-sight. Tent-making bats like the two species below chew along the midribs of big leaves, collapsing them down into little shelters. They hold on to the midribs with their tiny little feets, and nap through the day bathed in the green light coming through their tent walls. They also build decoy tents, with no bats inside, possibly to foil squirrel monkeys and other bat predators’ efforts to find their real hiding places.

Image

These ones look like cotton balls. Way too cute.

IMG_8819

Other interesting defense mechanisms we’ve seen in La Selva include: the armadillos, hard to photograph because they like to crawl around in the underbrush in the dark; fer de lance snakes with a very nasty bite to impart on anything foolish enough to tangle with them; and bullet ants, inch-long little boogers that are named for their ability to make you feel, for 24 full hours, as if you have been shot.

IMG_8772

Then there are things like this tamandua (ant-eater) that see potential predators like us, squeak, and waddle over to a too-small tree in order to climb it slowly and cast timid and unhappy looks down at the scientists below. Not maybe as impressive a defense strategy… but still pretty adorable.

IMG_8753