Friday, June 15, 2012

Tarantula Hunting

'ello pretty!



Yesterday I returned from 2 weeks at  the coast of Esmeraldas, the province in the north-west corner of Ecuador, searching for tarantulas, family theraphosidae, for my research project.  The expedition itself was a success- we came back with a cooler full of tarantulas- and I had a great time at the 2 research stations we visited, exploring the jungle and searching for spiders.
View from the bluffs above Congal
The first station Alejandro & I went to was the Congal Biomarine Station, outside of the town of Muisne.  The park offices and lodge were small- just 2 buildings, a researcher lodge & a volunteer lodge/dining hall, but it was a great location, park to the front of it, and mangroves, Rio Muisne, and then the Pacific behind. The lodgings turned out to be more "advanced" than the next station, with brick walls and a shower for every researcher room, but hiking through the humid jungle made the showers appreciated!  At each of the 2 research stations, we had the same procedure for the week we were at each.  On the first day, we went out to the jungle with Vicente, the guide/handyman at Congal, and set up a series of 100 meter transect lines that we'd use as our search area.  Every day after that, we'd work a different transect line, one each day.  Trying to be looking for tarantulas at as many points in the day as possible, we did two searches a day- 3 hours in the morning after breakfast, and then the same amount in the late afternoon/early night, before we came back to camp for a late dinner.   Our usual procedure was to spend most of the morning looking for burrows and spiders roaming around (important for finding males- females make burrows which are easy to find, but males roam their entire lives), and in the evening most of the search period would be spend digging up burrows found in the morning.  Even considering they were big spiders, the burrows were suprisingly deep- even at Congal, where the tarantulas were smaller, some of the burrows were 3 feet long.  Sometimes, if the spider was at the mouth of the burrow, we could fish her out by sticking a twig in the burrow and jiggling it, so when we pulled it out of the burrow she'd chase after it, thinking it was prey or competition. Another, mostly unsuccessful idea was to flood the spider out- pour water into the burrow until the spider has to leave.  But becasue of the size of the burrows, that idea was a little impractical.
one of the trails in Congal
So ultimately, we usually had to dig the spider out.  We'd put a stick in the hole so it wouldn't collapse while we dug, and slowly work our way with trowels and machetes to the back of the burrow.  Usually after digging deep enough, when we pulled the stick out, the tarantula would try to flee, and we'd catcher her then, putting our hand in front of her so she'd run into our grasp, or dropping a tupperware container on top of her, then sliding the lid underneath to seal her in.  For all their reputation, the spiders at Congal showed basically no aggression- a couple times back at the station we were able to play with them, taking them out of their containers and letting them run free on our hands.  Their grip, from the tarsal scopulae- tiny hairs on the end of their feet, is surprisingly strong, and you could feel when they grabbed a twig thrust into their burrow.

After the week at Congal, we moved onto Caimito, an awesome reserve further up the coast, the cliffs and the Pacific on one side, and the town of Caimito on the other.  The town consisted of nothing more than a school, farms, 1 road, and 40 inhabitants.  It was weird, but really relaxing, to be in such a small, relaxed place.  And of course the lodge there was incredible- buried in the jungle away from the gravel road, three strories, it was all open air and made of nothing but bamboo walls and railings, wood floors, and thatched roof.  Even the shower was just a thatched hut, with a garden hose and gravel floor.  For all our meals we at with Raul, the direct of the reserve, and it's one employee.  Since the lodge was the only building of the reserve, we at in his house, a short walk away.  A 20 minute walk from the lodge was the ocean- you could see it from the top floor- and while the water was that great for swimming, it was a tiny beach with strong, ferocious waves, it was a great walk to take to sit at the base of the cliffs lining most of the coast!
first floor of the caimito lodge, hammocks and all
an arch in the sea-cliffs
a flower
The searching in Caimito brought out the big tarantulas- while the ones at Congal had been 4 or so inches across, some of the Caimito spiders were easily 9 inches long with their legs spread out.  It was crazy to thing of arachnids being so large, but awesome getting to catch them and see them up close.  The most beautiful was the 1 male from Caimito- out of 23 spiders from the whole trip, only 3 were males- who had a purplish iridescent sheen under bright light.  Though both Congal and Caimito were jungles, they were certainly drier than the jungle of the Amazon- it only rained a couple of times at each place, and the soil was, for the most part, fairly dry- meaning we didn't have to dig through mud!  Seriously though, I think that definitely explains the tarantulas.  In the Amazon, many tarantula species are arboreal, because ground burrows would be more prone to collapse or flooding in a constantly humid and rainy environment.  One creature I saw plenty of here, and in the Amazon, were bullet ants.  An inch long, they crawled over tree trunks, looking more intimidating than the tarantulas.  One night, i Made the mistake of stirring up a bullet ant next.  Thinking it was a tarantula burrow, I stuck a branch in it to fish for the spider, and ended up fleeing as dozens of massive, lethal ants (6 bites is usually fatal) came swarming out.
photo op...
...and size comparison
Finally though, we had to lead, and on our travel day went an hour further north on the coast for an afternoon to visit Mateo, my host brother, who was studying cetaceans, whales and dolphins, as by-catch of the fishing industry.  While we were with him, we went out out the water with some of the local fisherman to watch them put their nets out, and record any dolphins they caught.  Thankfully, the only dolphins I saw were free swimming spinner dolphins- a kind most famous for it's huge leaps and jumps into the air.  We did however, bring in several dolphin fish, dorado, and 4 big marlins, before we came back to port and Alejandro & I returned to Quito, ending hte adventure in the Jungle, and almost ending my time in Ecuador.