Tag Archives: herpetologist

What do you mean their dorsal spots ain’t right?

http://news.mongabay.com/2010/0414-hance_matrix.html

When I first embarked on doctoral research study it was clear that climate change had a great impact on amphibian decline as did disease along with pollutants (toxicants). Although I eventually transferred from a program that would allow me to investigate such issues, the topic will continue to warrants a lot of attention. I wanted to do work on a project that had interested me as a zoo keeper and one that I thought, at least at the time would be very applicable to carnivore preventive medicine.  I still found the topic of examining synergistic effects of pathogens, global warming, and toxicants on herpetile health to be really interesting, but creating a model to study these factors seemed a lot more difficult when I set out to mimic nature and modify it in a lab. In fact, this post may dissuade or encourage you to pursue an advanced degree.  In graduate school they don’t spoon feed you information and many advisors work with students on projects that are beyond their scope of expertise. This is not at all uncommon. I came in with some background studying helminth parasites in plethodontid salamanders (don’t get too excited now) and was hoping to develop a related project with ambystomatid salamanders (e.g., tiger salamanders, spotted salamanders, etc.).   The one thing about mole salamanders is that your field season is abbreviated as in a couple of days long and if you miss the mass migration to vernal pools where mole salamanders breed, you have to wait another season. Migration is triggered by several factors (i.e., ground and ambient temperatures, humidity, barometric pressure, and light/darkness).  Hence, the movement of  these explosive breeders is somewhat predictable to the seasoned herpetologist, but expect the unexpected.   The second objective was to find a model pathogen that I could use to infect a laboratory population of wild caught spotted salamanders and then introduce variations in the photoperiod through the use of artificial light. Finally, I was planning to find some pollutant that was a known toxicant. Not too long ago an interesting study had been published on the effects of toxicants on salamander spot patterns.  If you didn’t know spotted salamanders normally have two symmetrical rows of dorsal yellow spots on a dark dorsum (back), you do now.  Stress  from toxins or  lack of water due to warming temperatures are considered potential etiologies for these aberrant dorsal spot patterns. This may be a subtle anomaly compared to additional limbs or something more bizarre, but it’s a great indicator of ecosystem health.  Anyway, I established that I would select malaria, a vector-borne disease which effects non-human animals including species of mammals, and birds as well as amphibians.  I was just ready to go out and collect specimens when the opportunity to work on a zoo project was made available. As much as it sounds “insensitive” that scientists continue to conduct laboratory studies that require sacrificing wild caught specimens, it’s occasionally imperative to conduct these investigations for the benefit of the species. I must say that I certainly prefer working on projects that do not involve terminal procedures and fortunately I have had other opportunities.

Dr. Jordan Schaul, Zoo Keeper Emeritus

New Hampshire Fish & Game