Spelling suggestions: "subject:"4thyear"" "subject:"5thyear""
1 |
Disturbance and Environmental Effects on Staging Roseate Tern Parent-Offspring Interactions and Hatch Year Survival at Cape Cod National SeashoreDavis, Kayla L. 31 January 2017 (has links)
The study that I detail in the following thesis is a component of a three-part collaborative project to provide the U. S. National Park Service and Cape Cod National Seashore (CCNS) with data needed to inform management decisions for protection of the endangered northwest Atlantic Roseate Tern (ROST) during fall pre-migratory staging. This study was designed to address objectives related to hatch-year (HY) ROST behavior and survival in response to human and non-human activities and environmental variables at CCNS. Behavioral data showed that disturbance, specifically human and non-human activities, were related to increased HY ROST locomotion (flying and walking). We also found that environmental variables, including day of season and time of day were related to increased locomotion. Flock-level HY ROST begging behavior was decreased in the presence of human disturbance, but we did not see the same effect at the individual level. We found no evidence that the observed behavioral effect of disturbance resulted in decreased residency, recruitment, or staging duration of HY ROST at CCNS. Our work demonstrates that disturbance events around staging flocks have behavioral consequences, but it is unknown whether HY ROST behavioral responses to disturbances are great enough to impact survival after departure from CCNS. A conservative and proactive management strategy to minimize the potential for negative carryover effects on survival should limit ROST exposure to disturbance, particularly human activities, by exclosing staging sites between mid-July–mid-September to encompass the period of time when the highest number of ROST use CCNS. / Master of Science / The study that I detail in the following thesis is one component of a three-part collaborative project to inform management decisions for protection and recovery of the endangered northwest Atlantic Roseate Tern (ROST) population while they prepare for southward migration at Cape Cod National Seashore, MA (CCNS). This study was designed to address objectives related to hatch-year (i.e., HY, birds that were just hatched on the breeding grounds and now flying south for the first time) ROST behavior and survival in response to human and non-human activities and environmental variables at CCNS. We found that disturbance, specifically human and nonhuman activities were associated with increased locomotion (walking and flying). We also found that certain environmental variables, including day of season and time of day were related to increased locomotion rates. Additionally, proportions of HY ROST within a flock that engaged in begging behavior decreased in the presence of human disturbance, but we did not see the same effect at the individual level. We found no evidence that the observed behavioral effect of disturbance resulted in decreased residency, or time spent at CCNS by HY ROST. Our work demonstrated that human activity around tern flocks had behavioral consequences, but it is unknown whether HY ROST behavioral response to human disturbances was great enough to impact survival after departure from CCNS staging grounds. A risk-averse management strategy would entail limiting ROST exposure to potential human disturbance by closing off staging sites between mid-July–mid-September to human activity to encompass the period of time when the highest number of ROST use CCNS.
|
Page generated in 0.0235 seconds