Saturday, April 7, 2018
Sarah Lawrence College Center for the Urban River at Beczak
35 Alexander Street, Yonkers, New York
For more information and registration, see Seminar 2018.
Urban Wildlife Appreciation Day
Herpetologist Thomas Duchak, Hoffstra University
Held Saturday, February 10, 2018, 3:00 p.m.
Church of St. Paul and St. Andrew
West 86th Street and West End Avenue in Manhattan
Hatching Failure in a New Jersey Wood Turtle Population
Thomas Duchak is freelance researcher, environmental educator, and adjunct professor who developed a fascination for turtles at a very young age. In 2016 he obtained his Master of Science in Biology at Hofstra University, studying the reproductive ecology of wood turtles in northwest New Jersey. He continues to study several aspects of wood turtle biology and conservation including population dynamics and demography, home range and habitat use, thermal biology, population genetics, and nesting ecology, but his major research interests involve identifying factors that limit reproduction in wild turtle populations.
North American wood turtles (Glyptemys insculpta) have been suffering a range-wide population decline since the mid-1900s. Habitat destruction and degradation have already eliminated numerous wood turtle populations while threats such as illegal poaching for the pet trade, unnaturally high predator populations (e.g., rodents, raccoons, skunks, etc.), automobiles, and agricultural machinery continue to negatively impact existing populations. Monitoring efforts of these turtles usually involve population surveys to assess population viability but seldom investigate rates of reproductive success.
Since 2013, Thomas has been collecting annual wood turtle nesting data at a turtle nesting site in northwest New Jersey. Despite being one of the state's premier wood turtle sites, the annual overall hatch rates for the entire population are always low. Some females in the population always have bad hatch rates for their clutches while other females have good or variable hatch rates for their clutches. The study concerns one population in which some females always have poor rates of success and this drags the entire populations yearly success rates down.
To gather more clues about the causes of maternally linked hatching failure in this population, Thomas has extended the scope of this study to include more study areas and two additional species that share nesting habitat with wood turtles. He is also surveying these turtles for biocontaminants that affect hatching success in turtles and other egg-laying reptiles. It is hoped that investigating the hatch rates and contaminant levels of wood, painted, and snapping turtles at several adjacent sites will reveal whether the low hatch rates are indicative of a localized problem that only affects certain wood turtle populations or a more widespread problem that compromises the well-being of several species.
Our meeting place: The Church of St. Paul and St. Andrew is located on the Upper West Side of Manhattan, just steps from the 86th Street subway station on the No. 1 train (Broadway line). Please use side entrance on 86th Street.