Wednesday, June 25, 2014

Nasty neighbors—everybody’s got one

They’re noisy. They cause a ruckus. They tromp through the front yard. Everyone has an annoying neighbor—even anoles. And anoles are particularly grouchy homeowners. Many Anolis lizards are highly territorial, actively defending the area in which they live against the intrusion of other anoles. This behavior has been well studied in males—most are highly intolerant of trespassers, and will display at, chase, and in some cases, even physically fight with other males that wander into their territory. But what about females? Fewer studies have focused directly on female territorial behavior, and as a result, many exciting research questions remain unanswered.

For the past three weeks, I’ve been at El Verde field station in Puerto Rico trying to gain some insight into the territorial behavior of female Anolis gundlachi lizards. After a few frustrating days (I found maybe 10 females when I expected to see hundreds), I finally got the hang of it. With those days behind me, I settled into three small plots and (quite literally) stalked some female A. gundlachi. I’ve been keeping track of where females spend time, denoting where they perch within plots in relation to other females and males that reside in the area. I’ve also been observing their behavior, and trying to denote behaviors associated with territoriality in particular. From what I’ve seen, females are grouchy territory owners too.

Similar to males, females seem to perch consistently in the same areas within a habitat. Also like males, the females either keep a safe distance from others or suffer the consequences—I’ve seen many an intruding female chased from a favorite perch of the resident

And today I got the white whale—a full-blown, locked-jaws fight between two females. See the shot below, sorry for the terrible picture quality! 

Female A. gundlachi hash it out over--let's face it--a pretty lack-luster tree. 
I found these feisty ladies while wandering down a forest trail. They were obviously agitated, and so I stopped to film. After doing pushups at each other for several minutes, the females ran at each other and danced around the tree joined at the jaw for almost five minutes. Finally, one female literally ran the other off of the perch, chasing her down the tree and into the leaf litter. Oh, and our winner did a few follow-up pushups—just for good measure.

While I feel sorry for the battered trespassing female, it was exciting for me to see a territory dispute escalate so dramatically. I’ve collected territory data and observed several hours of female behavior, but nothing yet to this degree.

It’s been a great three weeks here at El Verde, and I look forward to analyzing the data I’ve collected on this trip. Ole ola!