AA stalwart Liam Revell was forwarded the photo above on Facebook and decided to look into it. Here’s what he reports:
This impressive photo showing a Puerto Rican crested anole (Anolis cristatellus) being attacked by a Puerto Rican racer (Borikenophis portoricensis) was recently posted to the Facebook group ‘Biodiversidad de Puerto Rico’ by a photographer Benny Diaz. He has kindly allowed us to re-post his photo here and also supplied the following description of the predation event he witnessed transpiring in the Puerto Rican state forest Bosque Estatal Guajataca (translated from Spanish):
“I first saw this anole and tried to take a photo of it after noticing that it was marked with two different colored spots of paint on its back. As I slowly approached it, the animal suddenly reacted with a jump and just at that moment a Puerto Rican racer (Borikenophis portoricensis) appeared out of nowhere and captured the anole in midair!”
Although the predation event is remarkable in itself (and the photo capturing it terrific), perhaps even more notable is the fact that the lizard appears to have been marked by an investigator conducting research on anoles! After some (social media-aided) investigation of the matter, led by Puerto Rican USFW biologist and avid photographer J.P. Zegarra, this scientist revealed herself to be University of Puerto Rico Ph.D. candidate, and friend of Anole Annals, Luisa Otero. Luisa is studying anoles in Puerto Rico as part of a multi-institutional collaborative NSF project to investigate the vulnerability of tropical ectotherms to global climate change. More can be learned about this project, and Luisa’s research, from the project website.
Luisa recounts the following about this particular lizard:
“Yes, we took the Tb (Editor’s note: body temperature) of the poor lizard in the picture a few weeks ago in Guajataca. Prof. Hertz was here and we were taking body temperatures and operative temperatures from models. It was the last trip of the ‘ vulnerability of tropical ectotherms’ project!! I usually use paint to mark the lizards so we don’t re-sample them the same day. This poor guy was sampled two days in a row…. (that’s why it has two colors)… and a few weeks later was eaten by this Alsophis (Ed. recently renamed Borikenophis)… very sad.”
Some years ago, Manuel Leal and Javier Rodríguez-Robles conducted a study in which they investigated what happened when a Puerto Rican racer confronted a crested anole. I summarized the study in Lizards in an Evolutionary Tree:
“In laboratory trials, Leal and Rodríguez-Robles (1995) showed that the snake, (which can attain a length of more than 1m), attacked anoles much less often when the lizard displayed. Moreover, they demonstrated that when attacked, the lizards fought back, often biting the snake on the snout for as long as 20 minutes and managing to escape in 37% of the encounters (Leal and Rodríguez-Robles, 1995)—remarkable given the size discrepancy of the snake and the lizard.”
Diaz’s observations confirm that this behavior is not a laboratory artifact–crested anoles will chomp down and hang on for all their worth. But, just as in the majority of the lab trials, the valiant defense was for nought. After a few minutes, Diaz reports, the lizard
appeared to be immobilized (probably the result of the rear-fanged snakes venom) and the snake began to work the lizard around, little by little, until it was able to swallow it head first.
The time between the first photo (above) and the last one (below), in which the lizard is well on its way to digestion, was eight minutes.
It’s also worth mentioning the follow-up study Leal conducted. Again from Lizards: “
In field trials, Leal (1999) found that the extent of display behavior toward a snake model correlated with the endurance capacity of the lizard (as determined in subsequent laboratory trials); the greater the endurance capacity of the lizard, the more it displayed to an approaching snake model. Anole displays to predators may be an example of a pursuit deterrent signal (reviewed in Caro, 2005). By signaling their endurance capability, anoles may be indicating their ability to fight back, escape, and potentially even injure a snake (Leal, 1999).”