One of Black Rock Forest’s smelliest summer projects has been our Spotted Turtle (Clemmys guttata) trapping. According to Hazel, her ‘…whole car smells like sardine bait.’
With inspiration provided by Dr. Susanne Macey from the American Museum of Natural History, we (summer interns Piper and Hazel) set five funnel traps in Sphagnum Marsh over the course of four weeks in the hopes of catching and monitoring Spotted Turtles. These turtles are a species of concern in New York due to habitat loss, pollution, and their illegal collection for the exotic pet trade, amongst others. In other words, the sardine-smell is well worth the mission.
Despite our efforts, not a single Spotted Turtle was caught. This is somewhat concerning as Sphagnum Marsh has been a habitat for these semi-aquatic creatures in previous years, and a loss of the local population could imply a disrupted food web, increased predation, and overall ecosystem imbalance. Alternatively, they are still here but moved to another waterbody in the Forest or the timing of our efforts was off.
Nonetheless, the funnel traps were rarely empty. Fortunately, many Painted Turtles (Chrysemys picta) were caught, in addition to the occasional Brown Bullhead Catfish (Ameiurus Nebulosus) or Northern Watersnake (Nerodia sipedon). Over the summer, 32 Painted Turtles were caught and recorded. While these turtles face fewer threats than their spotted relatives, it is still important to monitor them as they are increasingly illegally poached for the pet trade and the data we record adds to our long-term database.
While looking through their Painted Turtle data, we found that only 28% of the turtles caught this summer were female. This is interesting because turtles have temperature-dependent sex determination, meaning the temperature of their nest affects the sex of the turtles in the eggs. Due to the hotter summers, we would expect an increasingly younger female population as more females than males hatch every year. Yet, more males were captured than females and those females were also rather old. It is possible that there are increasing female-eggs, but these eggs are not hatching or the very young turtles are escaping the traps.This emphasizes the need for continued efforts, including possible surveys to explore turtle nest disturbances like human-led habitat degradation and foraging by predators. Continued monitoring will help us better understand our local turtle population, especially as the world is seeing increased climate variability and undergoing rapid changes.
While no Spotted Turtles were caught this season, we remain hopeful that they are safe and happily living in Black Rock Forest (and maybe just prefer a more expensive brand of sardines).
By: Piper Jenkins & Hazel Calway