Estimating sustainable mortality limits for shorebirds using the Western Atlantic Flyway

Shorebird hunting in Barbados: Using stable isotopes to link the harvest at a migratory stopover site with sources of production

“…However, probabilistic assignments for all species indicated that juveniles harvested in Barbados could also have origins in parts of Alaska in the western portion of their breeding ranges. Watts et al (2015) assumed that only the Canadian portion of the American Golden-Plover population was exposed to harvest, while our results indicate that Alaskan individuals (juveniles) may also comprise a portion of the birds harvested in Barbados. In the case of the Short-billed Dowitcher, our results indicate that it was mostly juveniles of the eastern subspecies (L. g. griseus) that had high probabilities of being harvested in Barbados, whereas Origins of shorebirds harvested in Barbados 363 Watts et al (2015) assumed that both the subspecies that breed in the midcontinental region (L. g. hendersoni) and the eastern subspecies (L. g. griseus) were equally exposed to harvest in the Western Atlantic Flyway.…”

“…Little information exists on age-specific differential fall migration pathways for the Short-billed Dowitcher. Our results suggest that estimated sustainable continental harvest levels (Watts et al 2015) could possibly be revised upward for American Golden-Plover and downward for Short-billed Dowitcher. However, more information would be required on the routes and migratory connectivity of adult birds to provide definitive management recommendations.…”

“…This will allow the development of conservation and management options for these species that are better targeted at the segments of the population exposed to harvest. For example, a recent evaluation of North American breeding shorebird sustainable harvest levels was based on demographic and population parameters from potential production areas within the breeding range of the 4 species included in our study as identified by expert opinion (Watts et al 2015). Applying results from our study will allow estimates of sustainable harvest levels to be indicative of Nearctic population segments that are likely exposed to harvest in Barbados, and will allow the use of regional demographic estimates when available.…”

“…Substantial population declines have been reported in 65% of the Nearcticbreeding shorebird species that migrate via the Atlantic Flyway (Bart et al 2007, Andres et al 2012. Although the proximate causes of these declines are poorly understood for most species, harvest along migration routes and on the wintering grounds has emerged as a threat or potential contributing factor in shorebird declines worldwide (Zöckler et al 2010, Watts et al 2015, Pearce-Higgins et al 2017). In the Americas, shorebird harvest occurs in several countries and may negatively affect shorebird populations in the Western Atlantic Flyway (e.g., Hutt 1991, Vermeer and Castilla 1991, Canevari and Blanco 1994, Ottema and Spaans 2008, Burke 2009).…”

“…Furthermore, a recent evaluation of the harvest in Barbados showed that 18 species were recorded in hunting logs, with 6 species making up~98% of the harvest: Lesser Yellowlegs (Tringa flavipes; 54-67% of the harvest), Pectoral Sandpiper (Calidris melanotos; 11-23%), Stilt Sandpiper (Calidris himantopus; 6-8%), Short-billed Dowitcher (Limnodromus griseus; 4-11%), Greater Yellowlegs (Tringa melanoleuca; 3-7%), and American Golden-Plover (Pluvialis dominica; 1-6%; Wege et al 2014). Although the harvest levels of these species in Barbados are apparently within continental-scale sustainable limits (Watts et al 2015), their overall hemispheric harvest is unknown and could negatively affect some populations (Hutt 1991, Clay et al 2010.…”