Monday, March 18, 2013

Strawberry Poison Frogs



The strawberry poison frog (Dendrobates pumilio) is one of the most frequently seen charismatic creatures of the forest. The males call throughout the day in a sound that is like “eeh-eeh-eeh…”, which we’ve likened to winding a disposable camera, or the sound a sprinkler turning in a circle makes. Once I tuned into the sound, I am amazed at how frequently I hear it every day.

Of the three types of poison frogs here (in addition to the strawberry, there are the green and black poison frogs and the striped dart-poison frog), the strawberry poison frogs have one of the coolest reproductive systems I have learned about. Granted, I know very little about frogs. These tiny guys (only about 22 mm long) have biparental care- both males and females take turns caring for the babies. After a courtship period, the female lays eggs in a nest under the leaf litter and the male fertilizes them. The male tends the eggs, keeping them moist and guards them from other males (who may eat the eggs). Once the eggs hatch into tadpoles, they wiggle onto the female’s back and she carries them to tiny water pools that collect in the base of bromeliads or aroids (plants). She will deposit only one tadpole per pool, and returns every few days to lay unfertilized eggs in the pools containing her young, which they eat as they are maturing. Females are able to distinguish their own young, and will not provide eggs to feed unrelated tadpoles, even if they exhibit “begging behavior”. It takes between 43-52 days for tadpoles to transform into froglets, and they do not become sexually mature for another 10 months.

J.P. holding a frog. They are tiny!
Certain species of poison frogs have historically been used by South American human cultures to create poison tipped darts. The darts are rubbed across the back of a live frog, then used with blowguns. Not all of these frogs have been used to poison darts, though they are all commonly referred to as poison dart frogs.

Fun facts for the day! It's a lot of fun to learn about the animals we are seeing and hearing everyday, and it makes me appreciate them that much more.

Green and black poison frog, Dendrobates auratus. Photo by J.P. Drury

Monday, March 4, 2013

Ick


Feb 11

Tonight I had to kill the largest cockroach I’ve ever seen. It was dying in the shower, and I was so sweaty from hiking all day in the humidity I couldn’t ignore it (which is my usual tactic). It was pretty awful. Also, I have about a million mosquito bites and also potentially chiggers (according to JP). Working in the tropics can be really gross sometimes. 

sloth!


Feb 7.

Oh my gosh! I saw a sloth! Like a lot of other awesome things, it was just outside the field station. A few of the students saw it earlier today, just a big ball of matted fur up in a tree. I went out at dusk to help set up an experiment, and figured I should look for it on the way back. Sure enough, it was up and active (well, as active as sloths get), eating leaves and moving slowly in the tree. We had a little watching party- everyone standing around with their headlamps and binoculars. It was so fun to watch. Someone with a fancy camera and tripod got a good photo, suggesting it was a mom with her baby!

I didn't even try to get a picture, but I drew it instead :)