Observations from a Field Trip to Study Anoles in Puerto Rico

Anolis occultus sleeping on a branch. Photo by Jhan C. Salazar

I have had the opportunity to search for anoles in three different countries— two in the Caribbean (Puerto Rico and the Dominican Republic; I will write about my experience in the Dominican Republic, too) and one on the mainland (Colombia)— and it always surprises me how diverse this group of lizards is. This year, I finally went on a field trip after the craziness of the pandemic—or should I say, during the craziness of the pandemic? I went for three weeks to Puerto Rico along with the incredible Losos Lab combo (the ones at Washington University): Dr. Kristin Winchell (the leader of the team), Dr. Elizabeth Carlen (the new postdoc of the lab), Ari Miller, Ansley Petherick and me—and three other incredible people: Sarah Swiston (a grad student in the Landis Lab at Washington University), Albert Chung (a grad student in the Campbell-Staton Lab at Princeton University) and Armando Vera (a microbiologist from Universidad de Puerto Rico).

I have been on several field trips in the past working with different kind of organisms, but this field trip had something special; it was the busiest one I have ever participated in. Do not get me wrong here: I really enjoyed my time there. We were doing several experiments (that you will hear about in the future) focused on differences between urban and forest anoles.

Now, let’s talk about why I am writing this post. We arrived in Puerto Rico in August and stayed for most of the month, staying at Mata de Plátano Field Station and Nature Reserve. Since the moment I landed, I felt how warm and nice people from Puerto Rico are—there is nothing better than feeling welcome. Once we got to the field station, I also realized how much I love to be surrounded by nature and disconnected from the world—I did not have phone reception in the field station.

I am not going to lie: one of the reasons I wanted to go to Puerto Rico was to see some or all the endemic bird species this beautiful island has. I saw a few of them—the Puerto Rican owl or múcaro and the Puerto Rican lizard cuckoo or cuco lagartijero, just to name a couple. Sadly, I did not see species such as the Puerto Rican tody or the Puerto Rican parrot. However, this time we went for a different kind of group: anoles, particularly Anolis cristatellus.

Even though we were looking for Anolis cristatellus, this one was not the only anole that I wanted to see. There were another nie species that I was looking for—sadly, we did not go to Culebras, Vieques, or Mona, so I guess I’ll have to go back to see the ones I’m missing!

On our first day of sampling, we went to the city of Arecibo to look for A. cristatellus, and while we were looking for this species, I saw a weird-looking anole with some black spots in the back. This was when I realized that I had just spotted my second anole species, Anolis stratulus. In the afternoon of that day, we were working in Mata de Plátano when Ari said “Hey Jhan, there’s a crown giant,” and I thought, “there’s no way this is happening so early on our field trip”; but it was true! We saw a beautiful emerald-colored anole, Anolis cuvieri. Later that day, I spotted my fourth species, one small with white lines on each side of the body, Anolis pulchellus. Four anoles in one day! How crazy is that?

Adult male Anolis cooki basking on a tree trunk. Photo by Jhan C. Salazar.

It was not until our second week that I found my fifth species. This time we were in a small forest patch in Mayagüez. We were walking in the forest, and I saw a familiar-looking anole, but I was not sure what it was. I asked Ari which species it was, and he said “that’s Anolis krugi.” On our last days in Puerto Rico, we went to a couple of places where we found the anoles that were missing from my checklist. Our first stop was El Yunque National Park—if you go to Puerto Rico, you should go there. I was impressed by how different the Colombian mountains are from the Puerto Rican ones. Before we even started to hike, someone pointed out an anole on a palm tree (sadly, I do not remember who it was), and it was another green anole! But this time, it was Anolis evermanni, and once again I was amazed by how easy it is to see some species when I used to spend weeks looking for even one individual of one species in the Andes.

When we were about to start hiking, Kristin said, “that’s Anolis gundlachi, look at those blue eyes!”. Once I heard that, I ran to see this anole; when I saw it, I realized that anoles are a crazy group. I did not know they could have blue eyes, or maybe I never noticed it until that moment. The next day, we went to Cabo Rojo, and there we found two species: Anolis cooki and Anolis poncensis. In this place, Sarah, Armando, Kristin, and I were walking on a small forest patch, and we found a grey anole, A. cooki—and again, I was surprised. I never thought anoles could be grey too! What can I say about A. poncensis? Well, I saw it for a brief period—it is a fast species. When we were walking, Armando yelled “Anolis poncensis! I told you it was here!”. Armando pointed the lizard out to me, but I did not see it until it started running; then, it stopped for one second, and in that second, I saw how beautiful that species is—so small, yet so fast.

I had just one species missing, but this story is unique. At the beginning of the field trip, I was talking with Armando about the anoles he saw when he was working with Anna Thonis (a grad student at Akçakaya Lab at Stony Brook University) just a few weeks before, and he said he was missing Anolis occultus—that was the first time I heard about that species. I did not even know how it looked. We made our quest to find that species. While we were in Mata de Plátano, there was another team working on anoles too, and one of them, Alejandro, told us where we could find this anole. That night, Armando and I went to the forest to look for A. occultus; we went at 9:00 pm and returned at 12:30 am empty-handed; we did not see it. A few days later, Armando went on his own to look for A. occultus, and again, he did not find it. Another night, Albert and the other team went looking for A. occultus, and they asked Armando and I if we wanted to join them, but we were tired; the next day, Albert showed us a picture of A. occultus—yes, they found it. I asked Albert to join Armando and I to look for this occult species; that night, we went to look for A. occultus from 10:00 pm to almost 1:00 am, and once again, we were defeated, with no clue where this species was.

On our last night, a Saturday night, Armando, Ansley, Ari, Sarah, and I were determined to find A. occultus. We started looking at 8:00 pm or so. We walked and walked, looking here and there, minutes passed and nothing. I thought we were going to leave Puerto Rico without seeing this species, and at 9:25 pm—yes, I recorded the time—I looked at a branch with something in it, and there it was. I realized that we had found it; after all these attempts, there it was, Anolis occultus. I said “found it, we finally found it”; everyone was excited, especially Armando. Ari then said, “there must be more individuals here,” and sure enough, Ari found another one! We took hundreds of pictures of those two anoles, and that was when I realized that in three weeks, I saw all ten anoles species that Puerto Rico has!

I feel thankful to visit and work in such an amazing place like Puerto Rico, with amazing people, amazing beaches, and food—particularly, mofongo and Church’s Chicken (they never got my order right, but I still like it). Hopefully, I will be back to work a little bit more, but for now: “Con un cariño profundo en ti la mirada fijo”—“With deep affection fixed gaze on you”—poem to Puerto Rico by José Gautier Benítez