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Bradford S. Keitt

Publications and source records attributed to Bradford S. Keitt.

2 recordsLinked to original sources

Satellite tracking supports hypotheses of breeding allochrony and allopatry in the Endangered Pterodroma hasitata (Black-capped Petrel, Diablotin)

Pterodroma hasitata , the Black-capped Petrel (locally known as Diablotin), is the only extant Pterodroma petrel nesting in the Caribbean. The species is listed as globally Endangered by the IUCN and was recently listed as endangered under the U.S. Endangered Species Act. Pterodroma hasitata show a phenotypic gradient, ranging from a darker, smaller form to a paler, heavier form, that is reflected in a strong genetic structure. This phylogenetic divergence suggests the existence of at least two distinct breeding populations. We report on pre-breeding movements of two male Pterodroma hasitata , one of each form, tracked by satellite from non-breeding areas in Gulf Stream waters of the western North Atlantic Ocean to breeding locations in Hispaniola in late 2019. Based on a combination of tracking locations, location error classes, battery voltage, and satellite communication schedules, we infer that the light-form petrel visited a nest in central Dominican Republic during 2 to 8 October and 9 to 15 October, and the dark form visited a nest in southeastern Haiti during 9 to 22 November and 29 November to 3 December. This information supports earlier suggestions that Pterodroma hasitata forms breed in allochrony and in allopatry, both of which may be a driver of speciation.

North Carolina

Framework for assessing and mitigating the impacts of offshore wind energy development on marine birds

Offshore wind energy development (OWED) is rapidly expanding globally and has the potential to contribute significantly to renewable energy portfolios. However, development of infrastructure in the marine environment presents risks to wildlife. Marine birds in particular have life history traits that amplify population impacts from displacement and collision with offshore wind infrastructure. Here, we present a broadly applicable framework to assess and mitigate the impacts of OWED on marine birds. We outline existing techniques to quantify impact via monitoring and modeling (e.g., collision risk models, population viability analysis), and present a robust mitigation framework to avoid, minimize, or compensate for OWED impacts. Our framework addresses impacts within the context of multiple stressors across multiple wind energy developments. We also present technological and methodological approaches that can improve impact estimation and mitigation. We highlight compensatory mitigation as a tool that can be incorporated into regulatory frameworks to mitigate impacts that cannot be avoided or minimized via siting decisions or alterations to OWED infrastructure or operation. Our framework is intended as a globally-relevant approach for assessing and mitigating OWED impacts on marine birds that may be adapted to existing regulatory frameworks in regions with existing or planned OWED.

Biological Conservation