Dr. Cohen and Ph.D. student Amanda Cheeseman collaborated with a team of researchers on a successful proposal to the SUNY-ESF administered USDA McIntire-Stennis Grant competition that focused on using microsatellite DNA to quantify dispersal of New England cottontails from their home ranges. The relatively new technique was pioneered by scientists at the University of Idaho, as published in a recent
Wildlife Society Bulletin article.
New England cottontails may disperse to new habitat in long distance movements of 100 meters or more, or may slowly bud a new home range off their existing one if there is adequate local habitat. Amanda will use radio-telemetry to quantify rates of long distance dispersal. To examine rates and spatial patterns of budding, she will compare DNA in pellets gathered during winter surveys to DNA in tissue collected from young and adult rabbits captured in the summer. Understanding dispersal patterns in this imperiled species is critical for planning restoration and protection of their habitat. The other researchers on the proposal were Dr. Christopher Whipps, a parasitologist and geneticist at SUNY-ESF, and Dr. Sadie Ryan, a spatial ecologist at the University of Florida.
PhD student Alison Kocek, along with collaborators at the University of Maine, piloted a study in 2014 involving the application of PIT (Passive Integrative Transponder) tags to tidal-marsh sparrows within New York City and southern Maine. During previous field seasons, multiple recaptures of sparrows (systematically and at nests) throughout the field season led to trap avoidance and possibly increased the risk of nest abandonment by adult sparrows. To reduce both of these potential problems, Alison chose to attach a PIT tag to a nesting birds’ color band as a novel way to allow researchers to passively identify birds attending a nest. These tags do not require a power source, are light weight (0.1g), and remain with the birds for their entire lifespan. This reduces potential negative impacts from frequent handling of birds, while allowing researchers to collect more information with less effort than traditional recapture methods.
Alison and fellow researchers applied tags (using epoxy and electrical tape) to the color bands of female saltmarsh sparrows (ME and NY), Nelson’s Sparrows (ME) and hybrids (ME), and male and female seaside sparrows (NY) captured throughout the 2014 field season. She also banded male seaside sparrows with PIT tags because they are known to occasionally aid in feeding young and are notoriously difficult to capture during targeted netting at nests. Tags were applied to 88 individuals in New York and 84 in Maine. Once several individuals were tagged at a study site, researchers began placing RFID (Radio Frequency Identification) reader antennae next to active nests for 15-minute intervals to determine which individuals were attending nests. To confirm that RFID readers were only capturing the IDs of the attending adult and not another bird passing by, a subset of these same nests were later targeted for netting. In all instances where targeted netting resulted in a capture, individuals trapped in nets were the same individuals whose PIT tag ID was recorded by the RFID reader at the nest. Also, in every instance that an RFID Reader was unable to obtain the PIT tag ID of an individual, target netting determined that the attending individual was not marked with a PIT Tag. Thus, these data demonstrated 100% PIT tag readability and accuracy during the 2014 field season in both New York and Maine.
Alison plans to continue this work in 2015, and will tag new individuals as well as examine return and retention rates for previously tagged birds. Alison and Dr. Cohen conduct this research as part of the Salt Marsh Habitat and Avian Research Program (SHARP), a collaborative effort among several universities and agencies in the Eastern U.S. SUNY ESF’s portion of the project is funded by the U.S. Fish and Wildlife Service's Hurricane Sandy recovery program.