Leptophis Action

In one day, I was able to observe a pair of mating parrot snakes and a parrot snake preying on Lithobates (Rana) forreri.  As a disclaimer, the frog was tossed toward the snake out of curiosity by another student here, Paul, so it wasn’t a ‘real’ predation event.  Mahmood, however, suggested that this species of snake hunts for frogs, such as L. forreri, in the leaf litter during the day, while the frogs are inactive.

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A finished fence and a crocodile

After completing a fence to keep out the damn cows, Boa and I discovered that a 2-m crocodile had come to investigate.  The water is still very shallow, so it didn’t make an attempt to get away… that is, until we decided to strap a rope around it’s jaw and wrangle it to the shore.

Charles is shown stringing the crocodile’s jaw and Paul is the other individual celebrating the catch.

Patches of Tadpoles

What could be controlling the patchiness of tadpole density in the wetland?  There are areas, such as those pictured below, where tadpole congregate in large numbers and appear to move about as a school.  In a couple of cases, I notice one or two dead tadpoles being cannibalized in the mass, but here there was no obvious food source that had attracted them.   In the surrounding area (maybe within a 5 m radius), there were very few tadpoles; 2-3 per sqaure meter.

On a related note, how can I measure tadpole density?

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