I’ve recently arrived at El Verde Field Station in Puerto Rico for my first real field season working with anoles. My main goal is to carry out enclosure experiments looking at the different components (resource competition and predation) of the interactions between anole species. I’ll post more about the research later, but for now I want to give a rundown of the enclosures I’ll be using.
Anole enclosures have been used before, but it took some time to figure out what would work best for my purposes. The first enclosure experiments I know of were done by Pacala and Roughgarden in the Lesser Antilles, and involved fencing in large areas. The use of fences requires smooth plastic overhangs and lanes of cleared vegetation to prevent anoles from climbing and/or jumping out. I have several treatments needing replication, and such an approach would have been impossibly time- and labor-intensive given the resources at my disposal. Instead, I’m using commercially available ‘screenhouses’, normally used to keep the bugs and rain off at a picnic, to hold small populations of anoles.
Screenhouses are basically tents with mesh sides and no bottom, so they take mere minutes to set up. They measure about 3m by 4m at the base and are tall enough to stand in. They seem to work well for anoles, as they can be set up over bushes or small trees, and the roof provides some shade while the mesh sides allow some rain and sun through. The trickiest part has turned out to be securing the sides of the screenhouse to the ground tightly enough to prevent anoles from escaping. Luckily, our experiment site is adjacent to several abandoned and broken-down buildings, so there’s a ready supply of chunks of concrete rubble that can serve this purpose (less luckily, this has meant many trips hauling said rubble back and forth by me and my undergrad helper Tanner).
We’ve set up 12 enclosures now, and we’re halfway done introducing the anoles to their (temporary) new homes. We tested them with a few anoles of various sizes and species to make sure they don’t escape or overheat, and the early returns are promising. I’ll write again with a post-mortem on how the screenhouses hold up over the next few weeks – they seem able to weather a moderately windy day, but all bets are off if hurricane season gets an early start this year. Stay tuned…