Talking with locals to gain insight on the natural history of Sierra box turtle

The best part of working in the Sierra de Alamos protected area has been getting to know some of the families that have lived in this in area long before conservation ever became a priority. These people have been living with the turtles that I study their entire lives and as someone who did not grow up around turtles, I am interested in any and all stories related to their encounters. Such conversations often lead to a new insight on the natural history of the species I am interested in. In fact, I think most of my success in looking for rare turtles at any field site in Mexico has been a direct result of asking locals about their encounters and experiences with turtles. They often have detailed accounts of when, where, and what a turtle was doing when they encountered it. Although I learn many things in these conversations that might not be true, such as turtles singing on the Día de San Juan (June 23-25), much of what I do learn has led to success in the field. The point of this blog post is to 1) share an example of when a conversation with locals has led to success in finding turtles or learning something about their natural history, and 2) share photos that were sent to me from a local person of turtle behavior that has not been documented before.

A conversation with a local leads to our first encounter with the Sierra Box Turtle

When I first arrived in the Sierra de Alamos protected area to conduct field work in 2018, I didn't really have a clue where I was going to find the Sierra box turtle (Terrapene nelsoni). There is virtually no published information on this species. However, we do know that this species is endemic to Mexico's Sierra Madre Occidental mountain chain (meaning its found no where else) and that it has been observed at low elevations in the tropical dry forest and at higher elevations in pine-oak forest (Turtles of Mexico; Legler and Vogt 2013).

I arrived at the field site in the tropical dry forest during the wet season in July 2018 and I was joined by two university students from Sonora, Abel Domínguez-Pompa and José Carlos Verdugo-Gil, and a local from Sabinito Sur, Félix García who were to help me with my field work. Talking to Alejandro, a parkguard that works in Sierra de Alamos, we learned that the two turtles he had uploaded to iNaturalist were in fact found in the tropical dry forest. When I asked Alejandro I was with Félix García, who lives next-door to him en Sabinito Sur, and Félix knew exactly where he found this turtle.

The very next day of learning where Alejandro had seen this turtle, we woke up early and set out to look for Sierra box turtles in the area that Alejandro had seen two individuals copulating in years past. It wasn't even 30 minutes into our walk along a mountain side to arrive at the location Alejandro described and there it was! A beautiful male Sierra box turtle in the flesh (right photo). All the pictures I have seen of Sierra box turtles did not prepare me for the male that we found that day. This male was completely black! Had bright red eyes and practically without the yellow spots that characterize the species. The worn down scute rings on the carapace indicated that this male was very old, and based on studies on other box turtles I estimated this turtle could easily be over 50 years. To monitor this individual and hopefully find more individuals, we equipped him with a radio transmitter, which allowed us to constantly monitor this species.

After finding this male in the Sierra box turtle in the tropical dry forest, I thought I had struck the jackpot and that many more box turtles were soon to follow (this is usually what happens). However, this wasn't the case. Many people, many days, and two years of radio-telemetry has yielded very little success in finding Sierra box turtles in the tropical dry forest. We did find one dead individual during the Summer of 2018 near the first male we found, then one more male on that hillside in May 2019. In May 2019, we found three individuals (two females and one male) at a different site in the tropical dry forest. We also put radio transmitters on those three individuals and have been tracking them ever since. Still no luck on new individuals.

Novel Natural History Observations by a Local

Although we have had very poor success at locating box turtles in the dry forest, we have had success at higher elevations in the pine-oak forest. At the field site in the pine-oak forest we also got to know locals who have been cattle ranchers in the pine-oak forest for nearly a century and they are full of information on the Sierra box turtles. For example, two of the the most prominent observations that they seem to have made many times is observing the Sierra box turtle near leaf-cutter ant waste piles and horse dung. I was able to corroborate these observations after the first summer of looking for turtles and I found turtles at both waste piles of leaf-cutter ants, and at piles of horse dung.

In 2020, one of the locals from our pine-oak field site sent me pictures via Whatsapp that he took during the summer while he was attending to his cattle. These observations not only confirm their knowledge of the natural history of this species, but also provide one of the first evidences of courtship behavior in this species. The first picture I was sent was just a male (as can be seen by the abnormally big and melanistic head) (photo 1). The second is a turtle sitting on-top of a cow pie or horse dung (photo 2). We discovered in 2019 that turtles are eating dung beetles that are attracted to the waste piles, and not the dung itself. The last picture, perhaps the most significant, was a photo of two turtles copulating in the middle of a trail (photo 3). This is one of the first observations of this species copulating in the wild.

Photo 1 Photo 2 Photo 3

Talk to Locals to Better Understand the Organisms You Want to Study

Talking to locals and taking them seriously is something that many biologists need to do more. In my experience, biologists often think they know more about wildlife because they studied it in a university. It is true that many of the ideas that locals might have on local flora and fauna might not be biologically accurate. For instance, some locals still believe that Sierra box turtles sing at the start of the wet season on the Día de San Juan to signal that the rainy season has arrived. When in fact, toads are singing at the start of the wet season, not turtles. Nonetheless, locals often have a much longer history with the organisms that we aim to study. For this reason, it does not necessarily matter how they might interpret their observations, but the fact that they have more observations make any information they might have valuable. You never know, questions about the natural history of organisms may also lead to new friendships and free meals.