Revising the marine range of the endangered black-capped petrel Pterodroma hasitata: occurrence in the northern Gulf of Mexico and exposure to conservation threats

Abstract

The black-capped petrel Pterodroma hasitata is an Endangered seabird endemic to the western North Atlantic. Although estimated at ~1000 breeding pairs, only ~100 nests have been located at 2 sites in Haiti and 3 sites in the Dominican Republic. At sea, the species primarily occupies waters of the western Gulf Stream in the Atlantic and the Caribbean Sea. Due to limited data, there is currently no consensus on the geographic marine range of the species although no current proposed ranges include the Gulf of Mexico. Here, we report on observations of black-capped petrels during 2 vessel-based survey efforts throughout the northern Gulf of Mexico from 2010-2011 and 2017-2019. During 558 d and ~54700 km of surveys, we tallied 40 black-capped petrels. Most observations occurred in the eastern Gulf, although birds were observed over much of the east-west and north-south footprint of the survey area. Predictive models indicated that habitat suitability for black-capped petrels was highest in areas associated with dynamic waters of the Loop Current. We used the extent of occurrence and area of occupancy concepts to delimit the geographic range of the species within the northern Gulf. We suggest that the marine range for black-capped petrels be modified to include the northern Gulf of Mexico, recognizing that distribution may be more clumped in the eastern Gulf and that occurrence in the southern Gulf remains unknown due to a lack of surveys there. To date, however, it remains unclear which nesting areas are linked to the Gulf of Mexico.

Temporal and spatial segregations between phenotypes of the Diablotin Black-capped PetrelPterodroma hasitataduring the breeding and non-breeding periods

“…Petrels are susceptible to point-based attraction to continuous lighting of staffed oil and gas production platforms, and irregular lighting from support vessels and gas flaring, which can cause disorientation, grounding, and direct mortality (Ronconi et al 2015, Fraser and Carter 2018). Petrels may also be exposed to accidental oil spills and regular discharge of produced waters, through direct (contact with contaminated waters) or indirect (through bioaccumulation of contaminants in the food chain) entryways (Fraser et al 2006, Ronconi et al 2015, Jodice et al 2021). There is currently no active petroleum production in areas used by Black-capped Petrels in our study but active exploratory leases are present in the region and one individual in our study was present in leases 2435 and 2436.…”

“…More than 5,500 at-sea observations of Black-capped Petrels have been confirmed in the U.S. EEZ since 1938 (Sussman and U.S. Geological Survey 2014, Jodice et al 2021). Together with data from the Caribbean Sea, these records have been used to infer the global range and distribution of the species (Simons et al 2013, Winship et al 2018, Leopold et al 2019, Jodice et al 2021)(Figure S12). At-sea surveys are limited, however, by season, weather, time of day, sea state, and bias due to research funding.…”

“…The Diablotin, or Black-capped Petrel Pterodroma hasitata , is an endangered gadfly petrel endemic to the Caribbean and occurs in waters of the western North Atlantic Ocean, Caribbean Sea, and Gulf of Mexico (Simons et al 2013, Jodice et al 2015, Jodice et al 2021). The species is considered Endangered throughout its range (BirdLife International 2018) and is being considered by the U.S.…”

Seabird vulnerability to oil: Exposure potential, sensitivity, and uncertainty in the northern Gulf of Mexico

“…The northern Gulf of Mexico (nGoM) is a globally significant region for oil extraction and an important habitat for a wide array of avifauna, including seabirds (Jodice et al, 2019;Wilson et al, 2019). Seabirds may be exposed to oil through acute events (e.g., oil spills) and chronic pathways (e.g., persistent leaks or discharges; Jodice et al, 2019;Lamb et al, 2020). Acute events tend to be relatively well documented.…”

“…Given the levels of both acute and chronic exposure of seabirds to oiling in the nGoM, an assessment of the risk to seabirds from oiling appears warranted. To date, such an assessment has not been performed, mainly due to data gaps for the distribution and abundance of seabirds in this region (Jodice et al, 2019).…”