Radio Transmitters did not Affect Apparent Survival Rates of Adult Piping Plovers (Charadrius melodus)

Abstract

Assessments of possible adverse effects of transmitters on marked individuals is an important component of individual-based tracking studies, particularly for species that are listed under the U.S. Endangered Species Act. The breeding and post-breeding movements of adult Piping Plovers (Charadrius melodus) from the federally-threatened Atlantic Coast Population were studied by gluing miniature, 1.0-g, digital VHF radio-transmitters on their interscapular region. Mark-resighting data from 2015-2018 was used to estimate apparent survival rates for 289 adult Piping Plovers in Massachusetts, Rhode Island, and New Jersey in order to compare survival estimates between individuals with a transmitter attached and control individuals without a transmitter. Cormack-Jolly-Seber models were used for live-encounter data in a Bayesian framework to estimate apparent survival rates based on resightings of uniquely marked individuals. There was no evidence that mean apparent survival rates differed between adults with transmitters (0.756; 95% CI = 0.611 - 0.877) and without transmitters (0.673; 95% CI = 0.607 - 0.740). In addition, there was no evidence of differences in apparent survival rates between breeding location (state) or years. This study provides further evidence that radio transmitters glued temporarily to the inter-scapular region can be an effective tool to monitor local and regional movements of sensitive shorebirds, such as Piping Plovers.