Snakeaholics near and far, once again a warm welcome to the Snakeman’s Lair. It’s been way too long since the last episode, but fear not: today we are back with a bang in the person of our new guest. I had the chance to meet her around a year ago in the Netherlands, where she and her former supervisor travelled all the way from Arizona for the first Venomous Snakes as Flagship Species symposium. A few words were enough to realize that she would go places in the not so distant future- I mean, nothing gives a true “American badass” vibe more than driving around the iconic desert of Arizona tracking rattlesnakes, am I right? Today, it is my great pleasure to introduce Alexus Cazares.
At 22 years of age, Alexus has just started her PhD in Honolulu, Hawai’i (seriously, stop making us jealous), where she will soon kickstart her career in marine biology. Before moving to her new island home, Alexus graduated from the University of Arizona in Tucson, where she contributed to a project aimed at unraveing the impacts of development on reptile communities in a suburban area- with particular emphasis on rattlesnakes. To top it all off, she appeared in the documentary The Desert of Rattlesnakes to describe and promote her group’s work- the film as a whole is amazing, I highly recommend it.
Hi Alexus, thank you for joining us today! Before we go over your remarkable experiences in research and conservation, let’s start from the very beginning: when and how did you get hooked onto nature and wildlife biology?
Hi, thank you so much for having me! I would say that I have always been drawn to nature and animals. While growing up in the suburbs of Los Angeles, California, I took every opportunity to explore the natural world and learn about wildlife…whether it was in my own backyard, at the beach, or by visiting zoos and aquariums. Fortunately, I grew up in a family that loves traveling and spending time outdoors. At age 13, I saw my first snake (a Glossy Snake) in the wild and completely fell in love with reptiles. Then, at some point during high school, I realized that I was pretty good at science and enjoyed learning about biology. My passion for reptiles combined with my love of science led me to studying biology at The University of Arizona.
You recently obtained your Bachelor’s degree in Ecology and Evolutionary Biology from the University of Arizona, where you also started working as a field assistant for the legendary rattlesnake expert Dr. Matt Goode. Would you please explain to us what you and Matt’s group were researching and the daily routine of your work?
Yes, so I began working with the legendary Matt Goode back in the summer of 2017. When I first joined the lab as a sophomore, I worked on a project studying the urban ecology of lizard populations on The University of Arizona campus. Then, after a year, I began working on Matt’s long-term (2002-2014, 2017-2019) project studying effects of urbanization on a snake community and Gila Monster population. The aim of this research is to better understand effects of ongoing urban development on reptiles occurring at Stone Canyon, a residential golf community located at the base of the Tortolita Mountains in Oro Valley, Arizona. This site is particularly interesting because it is home to 21 snake species (3 rattlesnake species) and 13 lizard species (including the iconic Gila Monster). Matt began doing research at this site in 2002, two years after construction at this site began and the same year that the golf course was completed. In 2002, there were only 17 completed houses at the site. Now, there are 278 houses and construction at this site is still not finished.
To quantify the effects of increasing levels of urbanization on reptile relative abundance, we conducted nightly snake and Gila Monster surveys during the months of May-August. We conducted simultaneous surveys of the golf cart path and roads throughout the Stone Canyon development. While surveying, we captured each snake and Gila Monster that we encounter. We collected weather data and location information for each capture. Then, at the end of the night, we took the animals back to the lab for processing the next morning. Processing included taking several body measurements, determining sex and age class, inserting a PIT (Passive Integrated Transponder) tagging for individual identification, and collecting fecal samples. We also collected blood samples from Tiger Rattlesnakes (Crotalus tigris), which were used for genetic analyses. After collecting all of this data, we released the animal to its exact capture location within 24 hours. We conducted these systematic surveys five nights per week during the summer months (May 24-August 25) and recorded our effort, which allowed us to make comparisons across years. Outside of the field season, most of our work consisted of data analyses, writing manuscripts, attending conferences, and participating in science outreach.
Usually we tend to consider wildlife and urban areas as incompatible, which in turn leads us to assume that development is always a threat to biodiversity. Based on your urban ecology research, what is your take on this issue?
Great question! We do generally consider wildlife and urban areas to be incompatible, mostly because urban development often results in habitat destruction and a loss of biodiversity. I think that this is the case for most developments, especially those that are high-density and at the urban core. For example, we do see thriving populations of native lizards on The University of Arizona campus, but only three species. As we move further away from the city center and into more natural areas, biodiversity tends to increase and we find a greater number of reptile species. Low-density developments located at the urban fringe (like Stone Canyon) do not seem to pose as great of a threat to wildlife as we expected. Stone Canyon does a pretty good job of preserving desert environments and allowing space for wildlife to coexist with residents. Most of the houses at this site are built on large lots and surrounded by large areas of intact desert. I think that this is one of the main reasons why we are not seeing a dramatic decrease in snake diversity. It is also interesting that we observe a variety of large mammals at this site such as javelina, deer, bobcats, and the occasional mountain lion. In short, I think it really depends on the intensity and type of development.
The animals you worked with are highly venomous and widely feared- if not downright hated- by the general public. Are the people in your former study area aware of the presence of rattlesnakes, and how willing are they to coexist with them?
The people at our study site, Stone Canyon, are aware of the presence of rattlesnakes and Gila Monsters in their neighbourhood. Generally speaking, the people at this site are pretty willing to coexist with these highly venomous and widely feared animals. The employees, residents, and golfers that we talked to seemed genuinely interested in the research that our lab is conducting at the site. Most of them were very eager to share stories of reptiles and other wildlife that they had observed around their property or on the golf course. It is also important to note that being immersed in nature and preserving the surrounding desert environment are part of the appeal of living at Stone Canyon, which is likely the reason that residents do not mind sharing their space with wildlife.
Drawing from the results you have obtained over time, what future scenarios can we reasonably predict for rattlesnakes and Gila monsters in Stone Canyon?
Based on our results, we are seeing that species respond differently to increasing levels of urbanization at our site. Of the three rattlesnake species occurring at Stone Canyon, the Western Diamond-backed Rattlesnake (Crotalus atrox) is the only species that is not significantly affected by the number of houses at the site. In contrast, both Tiger Rattlesnakes (Crotalus tigris) and Black-tailed Rattlesnakes (Crotalus molossus) are decreasing in relative abundance over time. We believe that we are observing these trends because Western-Diamond-backed Rattlesnakes are habitat generalists and occur more regularly in urban areas. Tiger Rattlesnakes and Black-tail Rattlesnakes are habitat specialists and often found in rocky habitats. As these rocky hillsides are removed to make way for new houses, we would expect to see less and less of these rock specialists. As for Gila Monsters, we are not seeing any significant impacts on their relative abundance over time. Although the snake community and Gila Monster population at Stone Canyon seem to be doing alright for now, construction at this site is not finished. There may come a time when the costs of living at an urban site (i.e. road mortality) outweigh the benefits of living near a golf course.
At last year’s “Venomous Snakes as Flagship Symposium”, your supervisor Matt gave a talk discussing (among other topics) how cities can integrate nature within urbanized areas. What kind of measures do you consider most feasible and/or most effective to achieve this, particularly with respect to your target species?
We see a wide variety of organisms, not only at our study site but also in the Sonoran Desert generally. Clearly, various communities of snakes, lizards and other herps respond to different management strategies in unique ways, and we see these differences between rattlesnakes at our study site. Overall, I think the research we carried out as well as the body of research on urban conservation shows that management needs to be tailored to each case. Overall, we think that at least in Stone Canyon, preservation of habitat and the introduction of anthropogenic resources such as artificial irrigation are key. But these factors can change depending on the site and reptile community, which is why this research is so important.
You have been working on reptiles for the past three years, but I remember you telling me of how your first passion was marine biology- which you are now going back to for your postgraduate career. What fascinates you about marine life and how exactly are you planning to enter this field as a researcher?
Yes, I have left the world of Herpetology (not entirely though) to obtain a PhD in Marine Biology. As a kid, I always loved the ocean and had a deep interest in marine life. Now, I am most interested in studying marine ecosystems because of the human population’s dependence on them for food, oxygen production, climate regulation, and recreation. After taking a few Marine Science courses at The University of Arizona, I was really surprised and saddened to learn about all of the ways that humans are negatively impacting our oceans…such as effects of climate change on coral reef ecosystems, nutrient pollution in coastal ecosystems, and unsustainable fisheries. This motivated me to complete a Marine Science minor and led to my decision to study Marine Biology in graduate school. I want to increase my understanding of marine organisms, how they interact with one another and their physical environments, and how they respond to anthropogenic stressors. Based on the programs and labs that I applied to, I will likely be studying marine genomics, coral reef ecosystems, deep-sea ecology, or marine mammals.
Now that you’re getting into marine science, you are about to enter a completely different environment compared to your previous work in desert ecosystems. In your opinion, what are the benefits of working in different settings and disciplines for an early-career scientist?
I think that it is important for an early-career scientist to gain experience working in different labs and fields of study because it allows the student to get a better idea of the type of research that he or she would like to pursue in the future. As an undergraduate, I had the opportunity to work in two research labs, which allowed me to work with several study organisms (plants, microbes, and reptiles), use different methods, and learn many useful lab/field techniques. These research experiences helped me develop as a scientist and learn transferable skills that can be applied to many fields of science.
Lastly, Alexus, our interview ends with a look to the future: what are your main aspirations and goals for your career as a scientist?
As far as the near future goes, my main goal is to obtain my PhD in Marine Biology at a competitive research institution. After that, I aspire to pursue a career in academia as a postdoctoral researcher and eventually as a tenure-track professor. I aim to become a leader in Marine Science and conduct research that can be applied to conservation, policy, and management of marine resources. In addition, I hope to have an active role in science outreach so I can share my knowledge with the general public and inspire the next generation of scientists.
Thank you so much for joining us in the Lair today, Alexus! We all wish you the absolute best for your career- and I am especially looking forward to reading/watching your work. As for us, the Snakeman’s Lair will be back soon with another kickass guest from the world of wildlife, biology, and conservation. Stay tuned!