Author: Kristin Winchell

I am an Assistant Professor of Biology at New York University. My first love is herpetology, but my lab works on urban evolutionary ecology in diverse organisms (but primarily anoles!).

A Costa Rican Anole… with Eyespots? (ID Help Please)

By Kristin Winchell

On December 22, 2015

In Ask the Experts

My friend, Ricardo Kriebel (post-doc at University of Wisconsin – Madison), asked me for some help identifying an anole he came across in Costa Rica. He took these photos a couple of days ago in Cerros de Escazu, San Jose, Costa Rica in a cloud forest at ~2000m. Can anyone identify this species for him?

Ricardo reports that the lizard was unusually easy to catch (which says a lot since he is a botanist and not accustomed to hand-catching anoles). He came across it on the ground in the leaf litter and it didn’t move when he got close to it. Weather wasn’t likely to blame for it’s sluggishness as it was fairly warm out. Maybe this species relies heavily on crypsis? The body pattern in the photos above certainly looks like it would blend in well in leaf litter.

Ricardo also pointed out that on the top of the head the pattern resembled eyes. He noted that eye mimicry is common in this region in insects as a defense against predatory birds (e.g. Janzen et al. 2010). He proposed that perhaps the pattern on the top of this anole’s head was a similar type of mimic meant to resemble the eye or face of something an aerial predator should be wary of, like a snake. In a quick search I was unable to find any papers proposing mimicry of this type in anoles, so I turn to the Anole Annals readers. What do you think? Eyespots or random pattern? Does anyone know of any research on potential mimicry of this type in anoles?

Anolis sagrei Survey Continued: Eleuthera, The Bahamas

By Kristin Winchell

On November 16, 2015

In Notes from the Field

I just got back from a short trip down to Eleuthera in The Bahamas where I was assisting Anthony Geneva (Harvard post-doc) in sampling lizards. Also along for the trip were Sofia Prado-Irwin (Harvard Ph.D. student) and Rich Glor (University of Kansas). We went with the main goal of sampling Anolis sagrei from four habitat types found commonly in the Bahamas as an extension of an ongoing project in the Losos lab (previous posts from: Rum Cay, Concepcion Island, Ragged Island, Bimini, Mangrove habitat, and Great Isaac Cay). Specifically, we were looking to sample Anolis sagrei in mangrove, secondary coppice forest, closed coppice forest, and beach scrub habitats. These habitats differ in the height of the canopy, density of the understory, and composition of plants.

This slideshow requires JavaScript.

We focused entirely on the southern half of the island near Rock Sound and Cape Eleuthera. We were successful in sampling two beach scrub habitats, two mature coppice forest, one secondary coppice forest, and one mangrove habitat. We were able to catch all four of the anole species found on Eleuthera: Anolis angusticeps, Anolis distichus, Anolis sagrei, and Anolis smaragdinus. We also encountered a number of other native herp species: the Bahamian boa (Chilobothrus striatus), Ameiva auberi, Eleutherodactylus rogersi, curly tailed lizards (Leiocephalus carinatus), and the Bahamian racer (Alsophis voodoo), as well as a couple of non-native species: Cuban tree frog (Osteopilus septentrionalis), and Hemidactylus mabouia.

This slideshow requires JavaScript.

In my own research I work with Anolis cristatellus, the Puerto Rican crested anole. I am always surprised when I catch A. sagrei by how much smaller they are than A. cristatellus, although very similar in appearance otherwise. On this trip, I was also surprised that the A. sagrei, as well as the A. angusticeps and the A. smaragdinus, appeared to be much smaller than those I had encountered on Bimini last spring.

We also found that the density of lizards was quite low compared to what we expected and what I had experienced in Bimini, both during the day and at night. In all four of the habitat types, we saw an abundance of hatchlings, juveniles, females, and small males, but relatively few full adult male A. sagrei. For A. angusticeps and A. smaragdinus, we encountered only a few individuals total during the week of sampling. This reminded me of an odd experience I had last fall in Puerto Rico with A. cristatellus. It was the same time of year and I had an extremely difficult time locating mature animals in sites where I had previously sampled large numbers during the spring and summer months. Instead, I observed a large number of very young animals and females. I’m curious if this is a coincidence or if perhaps there is a strong seasonal effect on either male behavior (i.e., reduced visibility outside of the mating season) or male abundance (i.e., reduced numbers because of mortality during the mating season). In other words, are the males still there, but hiding, or are they really lower in abundance in the late fall? Or maybe I was coincidentally unlucky on both trips… I am very curious to hear thoughts on this!

Anolis sagrei using coral ground habitat.

Finally, I want to end with a short natural history note on the habitat use of the A. sagrei in the mangrove habitat. In this habitat we observed A. sagrei using perches at drastically different heights: some were 6 feet up, others were on the ground. Interestingly, the ones on the ground did not appear to be in transit, but seemed to be using the pockmarked karst as perches, running into one of the many holes when approached. Has any one else observed this behavior before? It seems so different from the typical trunk-ground anole perch and behavior to me.

That’s all for now. Currently Anthony is sampling additional islands in the Bahamas along with Melissa Kemp (Harvard post-doc) and Colin Donihue (Yale Ph.D. candidate / Harvard visiting student). Best of luck to them, I can’t wait to hear how the rest of the trip went!

To Eat or Be Eaten: How an Anole Decides When to Forage

By Kristin Winchell

On November 10, 2015

In New Research

Anolis cristatellus in survey posture (photo by K. Winchell)

Foraging decisions are the result of a complex decision-making process involving intrinsic factors (physiology, body condition, cognitive ability, sex, ontogeny, etc.) and environmental factors (food availability, structural habitat, presence of predators and competitors). In short, it comes down to the tradeoff between the benefits of energetic gain and the potential costs of predation risk, missed opportunities for reproduction, and expended energy. However, little is known about the specifics of this process – what information are lizards considering when making this decision? By conducting manipulative field experiments on Anolis cristatellus in Puerto Rico, Drakeley et al. (2015) attempt to elucidate what environmental factors influence the decision to forage.

The authors conducted field experiments involving feeding trays in the wild. The Puerto Rican crested anole is a trunk-ground anole and a sit-and-wait forager. When receptive to feeding, it perches head down in “survey posture,” a behavior it reduces when satiated. Aside from movement associated with foraging and social interactions, this species typically remains stationary on a perch. Because of this, the authors were able to easily locate a focal individual and count the number of conspecifics present, using natural variation instead of manipulating the number of animals present.

In the first experiment, they manipulated the food quantity to determine how foraging decisions differ when food is plentiful versus scarce and how this is influenced by the presence of competitors. They found that lizards foraged faster when there were more conspecifics present and food was scarce. When no lizards were near the feeding tray and the feeding tray was full, the focal animal took longer to approach the tray to take the mealworms compared to when there were many conspecifics nearby. Interestingly, this was not related to overall local density, but rather to the number of conspecifics in the immediate vicinity. Therefore the decision to forage likely involves an instantaneous assessment of the local conditions rather than knowledge of the long-term population trends. The authors also considered several other factors and found that although body size was related to foraging latency (larger lizards were quicker to the feeding tray), no other environmental factors were relevant (temperature, humidity, perch height, perch diameter, local density of conspecifics).

Figure 1 from Drakeley et al. (2015). Latency to feed was correlated with the number of conspecifics present and abundance of food.

In the second experiment, the authors chose focal animals farther from the feeding trays and considered distance as a proxy for predation risk. The farther the lizard was from the tray, presumably the greater exposure it had to predators as it moved towards the tray. They found that under this scenario, when risk was elevated, there was more latency in the approach of the food tray. This effect was driven mainly by the increased use of intermediate perches rather than a direct approach across open ground. Increased latency to feed was observed regardless of how abundant the food was or how many conspecifics approached the tray, supporting the conclusion that this effect was because of the perception of greater predation risk (i.e. movement over a longer distance). They also found that larger lizards had a lower latency to feed (approached the feeding tray more rapidly) and lizards not in the foraging position had a longer latency to feed.

In summary, it seems that anole foraging decisions are quite complex. Lizards appear to weigh the risk of predation taking cues from conspecific behavior and abundance versus the abundance of food to make instantaneous decisions to approach a novel feeding source.

Drakeley M, Lapiedra O, Kolbe JJ (2015) Predation Risk Perception, Food Density and Conspecific Cues Shape Foraging Decisions in a Tropical Lizard. PLoS ONE 10(9): e0138016. doi:10.1371/journal.pone.0138016

Evolution 2015 Recap

By Kristin Winchell

On July 9, 2015

In All Posts, New Research

Evolution 2015 is officially over and we have all sadly left beautiful Guarujá, Brazil. There were a lot of great talks and posters and a great representation of South American students and researchers. For coverage on the conference as a whole, check out #evol2015 on twitter! The herps were few and far between (I only saw 2 in my 16 days in Brazil!) but the posters and talks on herps were numerous. Unfortunately, anoles were poorly represented at Evolution this year with only three anole talks and a couple of others that briefly highlighted anoles. If you weren’t able to make it to Brazil, I’ve got the recap for you here.

click to read more about Travis Hagey's research

A glimpse at the variation in gecko toepads

Starting off in one of the first sessions was a talk by Travis Hagey titled “Independent Origins, Tempo, and Mode of Adhesive Performance Evolution Across Padded Lizards.” Although his talk was mostly about geckos, he did shine the spotlight on anoles for a few minutes. He focused on the phylogenetic pattern of toepad adhesion in pad-bearing lizards: geckos, skinks, and anoles. Specifically he looked at how clinging ability (measured as angular detachment – check out one of his videos showing this) varied within and among clades. Unsurprisingly, he found that anoles don’t cling nearly as well as geckos. He also demonstrated that gecko toepad diversification best followed a Brownian motion model with weak OU and anole toepad diversification was best fit by a strong Ornstein–Uhlenbeck process. In other words, gecko toepads diversified slowly over a very long period while anoles were quickly drawn towards an optimum over a short time-period. Travis concluded that these patterns explain why there is a large amount of diversity in gecko toepads but not in anole toepads.

Next up was Joel McGlothlin, who also gave a non-anole talk titled “Multiple origins of tetrodotoxin‐resistant sodium channels in squamates.”

Species ID from Bimini – A. sagrei or distichus?

By Kristin Winchell

On March 31, 2015

In Anole Photographs, Ask the Experts

After looking through my photos from my trip last week to Bimini in the Bahamas, I was disappointed when I realized that none of us seemed to have any pictures of Anolis distichus. Or maybe we did? Among all the typical sagrei-looking anole photos was this guy:

Anolis distichus or Anolis sagrei???

Without telling you why I thought this was a distichus, or why others I have asked are torn between distichus and sagrei, I am curious what people think. What species is this?

Field Trip Recap: Herps of Bimini, The Bahamas

By Kristin Winchell

On March 29, 2015

In Notes from the Field

Anolis sagrei on the beautiful island of Bimini

I just got back from a 10 day research trip to Bimini in the western Bahamas along with Harvard post-doc, Graham Reynolds, Harvard graduate student, Pavitra Muralidhar, and UMass Boston undergraduate, Jason Fredette. We went with the simple goals of kicking off a research project in the Losos lab on Anolis sagrei and to observe as many other herps as we could.

We spent the majority of our time on South Bimini. We sampled from the well-maintained Nature Trail, where we found all four anole species (Anolis sagrei, Anolis smaragdinus, Anolis angusticeps, and Anolis distichus) and a Bimini boa among diverse habitat types, including blackland coppice and open Coccothrinax shrub. We also spent a couple of nights searching in some mangrove forest near the airport, which yielded only A. sagrei and A. angusticeps and in low abundance at that. The “Fountain of Youth” ended up being a gold mine for Sphaerodactylus nigropunctatus as well as boas — we caught 3 here.

Male Anolis sagrei

Anolis smaragdinus

Anolis angusticeps

We also did a fair amount of exploring. Our hosts for our house rental wanted to make sure we had a great time in Bimini and so they insisted on boating us out to a couple of the nearby islands for some snorkeling. They even provided us with the best full face snorkel mask I’ve ever laid my eyes on. We picked up a boat for the ride at the Intrepid Powerboats website. Of course, we saw this as the perfect opportunity to catch a few lizards. Our first destination was Gun Cay, a small island a few miles to the south of Bimini. Pavitra and Jason entertained our hosts by collecting shells and feeding stingrays. Meanwhile, despite our hosts’ curiosity that we wanted to go wander in the brush, Graham and I nabbed 10 adult male A. sagrei in less than an hour. We also saw several Ameiva auberi, Anolis smaragdinus, and some sort of very large rodent (does anyone know about Hutia reintroductions in the Bahamas?).

The following day, our hosts insisted we come with them to a small island 20+ miles to the north of Bimini (Great Isaac Cay) where they promised us dolphins and hammerhead sharks. On the way to the island we saw several dolphins, tons of flying fish, sea turtles, and several large nurse sharks. As we approached the island, I saw the mature Casuarina forest and yelled down to Graham from the crow’s nest tower, “I want to go explore there!” Our hosts got us as close as they could to the rocky shore (dangerously close it seemed, the hull almost hit the rocky karst island) and all four of us hopped onto the island. The island had an abandoned lighthouse and buildings from the 1800’s that we explored. We were shocked to not find a single anole on Isaac Island, although we did find Sphaerodactylus nigropunctatus and Ameiva auberi.

The isolated Great Isaac Cay with ruins from the late 1800’s.

The trip was a huge success. In total, we came across all but five of the reptiles of Bimini. Surprisingly, we were unable to find any Bahamian racers (Alsophis vudii) other than roadkills, though most of our field time was at night. Unsurprisingly, we did not find either of the blind snakes or the dwarf boa, the latter of which tends to be more common in the rainy season. As expected, A. sagrei was the most abundant anole on Bimini. We came across A. angusticeps and A. smaragdinus with equal frequency and actually encountered only a few A. distichus. We did most of our searching at night, so this may be a reflection on different sleeping behaviors rather than abundance.

In summary, we were able to observe:

140+ Anolis sagrei males and females
9 Sphaerodactylus nigropunctatus (black-dotted dwarf gecko)
1 Sphaerodactylus argus (ocellated dwarf gecko)
Dozens of Leiocephalus carinatus (curly-tail lizard)
5 Chilabothrus strigilatus fosteri (Bimini boa)
a handful of Anolis distichus, Anolis smaragdinus, Anolis angusticeps

We also saw a number of other herps that we were not able to catch or didn’t need data from:

Ameiva auberi (Bimini ameiva)
Eleutherodactylus planirostris (greenhouse frog)
Osteopilus septentrionalis (Cuban tree frog)
Hemidactylus mabouia (invasive house gecko)

This slideshow requires JavaScript.

Orange Coloration in Anolis cristatellus

By Kristin Winchell

On January 19, 2014

In Natural History Observations

A couple of days ago as I was feeding my Anolis cristatellus hatchlings and I noticed something really strange – one of the hatchlings had a bright pink/orange tail! I was really amazed at how bright and unusual it was so I immediately emailed Ambika Kamath who pointed out that this conversation is not a new one to Anole Annals and suggested I post on my anomalous pink lizard.

The pink-orange color is only on the tail and hind limbs and when I picked the lizard up the color faded as the lizard turned darker brown. The mother was unremarkable (not pink!), but one of the siblings also has some reddish tint to its tail, although not as apparent. I have not noticed this in any of my other hatchlings.

I’m curious if this is the same sort of coloration that other people have observed in Anolis sagrei. Some of the pictures look very similar to what I observed. Has anyone else observed this in A. cristatellus or any other species? Or maybe this sometimes happens in hatchlings and fades with age? For reference, here are the previous posts on Anole Annals regarding this topic:

It might be noteworthy that the hatchling is the offspring of two urban lizards from Mayaguez, Puerto Rico. In the other posts, it seemed like many of the observations of the red-orange A. sagrei were in urban areas. One of the posts mentions an orange color of palm trees and other manmade substrates in the suburban area where they observed multiple orange lizards. I wonder if this is an adaptation to something in the urban environment? Now that I think of it, I recall catching some lizards at my urban sites that had striking orange coloration on them, but none were completely orange and none looked pink. Also, I don’t recall my study site having a large amount of orange substrates, although many of the houses are painted bright orange, yellow, pink, etc. Any thoughts on this? I’ll keep an eye on this lizard and let you know how the color develops as it gets older.

Urban Anole Phylogenetic Study: You Can Help!

By Kristin Winchell

On November 12, 2013

In All Posts

A. cristatellus on a rooftop in Mayagüez, PR

Urbanization poses a major challenge for many species, altering natural environments in ways that few animals can tolerate. Despite this, some species persist and even thrive in urban areas. In my research in the Revell lab at UMass Boston, I’ve been studying adaptation in response to urbanization in Anolis cristatellus, the Puerto Rican crested anole. However, among anoles urban tolerance is by no means restricted to A. cristatellus. We suspect that readers of this blog have probably observed many different anole species occupying and thriving in urban areas. Consequently, we would like to ask for your help in gathering some information on this topic.