11 de septiembre de 2021

Studying Mountain Yellow-legged Frogs and Bd in the Sierra Nevada

The cold, rugged, and exposed peaks of the high mountains are not the sort of place that you would expect to find ectothermic animals. However, in the high Sierra Nevada in California, amphibians not only survive these harsh conditions but thrive. Some species have become so well suited to the high Sierra Nevada that they are found nowhere else in the world. One such amphibian is the Mountain Yellow-legged Frog, which is often the most numerous amphibian in the alpine and subalpine lakes and creeks where it occurs. Due to the unusual nature of the habitats that they live in, these frogs have very peculiar life histories. For starters, they live much longer than similar species of frogs, sometimes living as long as 15 years! The tadpoles also take longer to metamorphose, usually taking 2-3 years to transform into juvenile frogs and becoming gigantic for tadpoles in the process. For comparison, the tadpoles of most frogs species in the U.S. only take a fraction of a given year to complete metamorphosis. Mountain Yellow-legged Frogs also behave weirdly. In addition to being active at much lower temperatures than most frogs can tolerate, they also bask on rocks, logs, and the ground during the Summer to increase their body temperatures. During the Winter, they remain underwater as their water sources freeze, spending time moving around to the warmest patches of water and hunkering down in the mud at the bottom of the lakes and creeks. Evolving to survive in such a harsh habitat has made these frogs different from almost every other and resulted in a truly unique type of amphibian.

Unfortunately, as with many frog species around the world, the Mountain Yellow-legged Frogs have experienced severe population declines due to the emergence of Batrachochytrium dendrobatidis (Bd), a species of chytrid fungus that appears to attack the skin and heart of frogs. This fungus, along with the other causes of Mountain Yellow-legged Frog population declines, had such significant effects that the populations in the Sierra Nevada have been Federally listed as an endangered species. At one point, it was thought that the species would eventually go extinct. However, to the surprise of many, Mountain Yellow-legged Frogs have not only survived into the present day, but they are also thriving in many parts of their range. While Bd is still a significant threat and the endangered species ranking is still warranted, the future of these frogs looks much more secure than it did several years ago. But exactly how are these frogs persisting in the face of a deadly disease? What factors are contributing to their survival? And why are some populations still declining while others are persisting? Is there some sort of immunity that the frogs have been evolving, or is it possibly environmental factors?

The answers to these questions are unclear and researchers are trying better understand the struggle between Mountain Yellow-legged Frogs and Bd. The Briggs Lab at UCSB is one of the organizations at the forefront of Mountain Yellow-legged Frog research and has devoted a lot of time and effort to gaining a better understanding of this relationship. As part of this research, the lab sent a small group of students from the university into the Sierra Nevada to collect data on these frogs as part of a new study aimed at investigating the role of genetics in how frog populations and Bd interact. I was fortunate enough to be one of the assistants in that group and spent two full months conducting fieldwork in the Sierra Nevada this Summer. To collect our data, we backpacked out to remote locations across the Central and Southern Sierra Nevada on overnight trips, sometimes for six days or more at a time. We would then conduct a visual encounter survey of every site (population) we visited and tally up every Mountain Yellow-legged Frog adult, juvenile, and tadpole that we saw in order to get a better idea of the current population size. We then caught 10 adult frogs from each site and took both skin and tissue samples from them to retrieve their DNA as well as that of any Bd that was on the frogs. All of this work was done with the proper permits and done as efficiently and humanely as possible in order ensure that our impact of these endangered frogs was kept to a minimum. With the samples all collected at this point, all that is left is for the grad student in charge of the project to analyze the data, interpret the results, and write up a scientific report on the study.

This was an amazing experience for me in so many different ways. For one, it was so cool to be able to explore such remote and scenic wilderness areas and find these endangered amphibians in the middle of them. I got to handle endangered species, learn precise field methods, and engage in profession fieldwork that was completely different from anything I have ever done. I also got to see the wholistic view of a research project and make the connection between the big picture and the specifics that make it up. But perhaps one of the most valuable aspects of this experience was getting to know such a unique ecosystem at such an intimate level. Like everywhere I explore, I saw lots of wildlife, but spending 2 months in the Sierra Nevada did more than that. By paying close attention to the environment, I was able to detect changes in the rhythms of the ecosystem, such as when the transition from Summer to Fall occurred and when the birds started to migrate South. I was so in tune with the ecosystem that I could detect subtle changes that I never experienced in any other ecosystem. Thanks to this opportunity, I have become more passionate about the subtleties of the environment and have developed a great appreciation for one of the strangest frogs in the world.

For more information on the Mountain Yellow-legged Frog, please see my video on its biology and conservation. (https://www.youtube.com/watch?v=5mNsVf_FbVg)

Anotado en 11 de septiembre de 2021 a las 05:30 PM por tothemax tothemax | 22 observaciones | 1 comentario | Deja un comentario

17 de mayo de 2021

Herping Away the Pandemic: The 2021 Herping Season

Field herping, or the act of searching for reptiles and amphibians in the wild, has been one of my favorite outdoor activities every since my first survey with the Southwestern Herpetologist Society. Reptiles and amphibians are just such beautiful animals and the intimate knowledge of their life histories that is required to find many of them makes this process so much more rewarding than other forms of wildlife watching. In 2019, I decided to conduct a personal field project all on my own while working on my undergraduate degree at UC Santa Barbara in order to learn how to find wild reptiles and amphibians in Santa Barbara and what conditions were most suitable for different species. The 2019 and early 2020 seasons were very productive and taught me a lot about field herping and herp biology. Unfortunately, the middle of 2020 season was interrupted by the coronavirus pandemic. I was forced to leave campus and move back in with my parents. Although I was able to make a few trips back out to Santa Barbara to collect data that season, I was mostly restricted to the Western Los Angeles County area where I live. This forced me to broaden the scope of my project from a focus on Santa Barbara to Coastal Southern California more generally. This transition also resulted in me finding a bunch of new sites to look for herps, although the herping season had ended before I found most of them. As a result, I prepared and waited for the 2021 season to arrive.

Now, as the 2021 season draws to a close, I can say that the wait was worth it. Both as part of my study and just for fun, I did more herping and saw more herps this year than I have ever done in one season. The weather was not optimal this year, with comparatively little rain and extreme temperatures for Spring, and yet I still saw more than ever before. What rain did fall was enough for chorus frogs and slender salamanders to be found in oak woodlands. I was also able to find my first Monterey Ensatinas, a species that is very spotty in its distribution in Southern California. Thanks to a few sites in particular, I was able to find dozens of gophersnakes and rattlesnakes, including some very unusually patterned and colored individuals. Unfortunately, several of my encounters with rattlesnakes this season were close calls, so I will be meditating on those experiences in preparation for future expeditions. I also found several nightsnakes this year, a species that I have not seen many of. Skinks and alligator lizards were found in great numbers as usual, but I was also able to find them in new places. Despite the dry weather, I found a decent number of Ringneck Snakes this season, including some of the most beautiful ones I have ever seen. This season was also my personal record for the most kingsnakes in one season, with three of them being striped-phase kingsnakes that I found in San Diego County. Additionally, I spent a decent amount of time walking creeks this season and have become much more experienced in looking for Pacific Chorus Frogs, California Tree Frogs, Two-striped Gartersnakes, and California Newts in such habitats. Other amazing finds for this season included a black-headed snake, a legless lizard, a striped racer, a whiptail feeding on a jerusalem cricket, my first arboreal salamander, and a rattlesnake feeding on a pocket mouse.

With the exception of finding Western Toads, I saw every species I wanted to see this season and then some. It was an amazing experience and I will not forget it, as it is probably the only season of Coastal California Herping that I will ever be able to experience as fully. I learned so much from all my encounters and I can't wait to reflect back on these experiences again when I finalize my project in 2022.

Anotado en 17 de mayo de 2021 a las 05:49 PM por tothemax tothemax | 38 observaciones | 5 comentarios | Deja un comentario

03 de agosto de 2019

Reptiles and Amphibians of Santa Barbara County INat Project

Today, I have founded a new INat project entitled Reptiles and Amphibians of Santa Barbara County (https://www.inaturalist.org/projects/reptiles-and-amphibians-of-santa-barbara-county). This project is meant to increase our knowledge about the reptiles and amphibians that inhabit the Santa Barbara Region, one of California's great biodiversity hot spots. Please join the project and submit any observations of reptiles or amphibians you have seen in Santa Barbara County, California. The inclusion of details, such as behavior, temperature, humidity, weather, # of individuals, location in habitat, and any other information relating to the observation is highly encouraged.

Anotado en 03 de agosto de 2019 a las 12:28 AM por tothemax tothemax | 3 observaciones | 0 comentarios | Deja un comentario

5,000 Observations!

I have uploaded over 5,000 observations to INaturalist as of today. It has been nearly two years since I first got involved with this amazing citizen science outlet and contributing to it today feels as exciting as it did when I first started. Not only am I able to making a difference by helping progress scientific research through INaturalist, but I am learning so much about the animals that I encounter as I explore their worlds. As an aspiring zoologist, this is simply thrilling to me. I must make a big shout out to Greg Pauly of the Los Angeles Natural History Museum and Founder of the Reptiles and Amphibians of Southern California (RASCals) INaturalist project. I remember when he came to the Southwestern Herpetologist Society to give a talk about the RASCals project and talked about how he was doing important research with INaturalist data and how this data is created by ordinary people. It was then that I learned about INaturalist and that I became interested in getting involved. Looking back on it now, I am very glad I did.

Anotado en 03 de agosto de 2019 a las 12:18 AM por tothemax tothemax | 0 comentarios | Deja un comentario

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