Resightings of captive-reared and wild Piping Ploversfrom Saskatchewan, Canada

摘要

In 2002, flooding threatened Piping Plover Charadrius melodus nests at Lake Diefenbaker, a reservoir in south central Saskatchewan, Canada. Therefore, 80 eggs from 21 clutches were collected and incubated, with the resulting chicks raised in captivity. In total, 65 fledged chicks were banded and then released at nearby Chaplin Lake, Saskatchewan. Approximately 12 (18%) captive-reared plovers from these two releases were directly observed on the breeding grounds in Alberta, Saskatchewan and North Dakota, compared to 50% (8/16) for 2002 and 52% (26/50) for 2003 wild-fledged birds from Saskatchewan. During the winter (2002-2008), 9% (6/65) of the captive-reared plovers were observed, compared to 31% (5/16) of the 2002 and 30% (15/50) of the 2003 wild-fledged chicks. Resightings of captive-reared chicks on the wintering grounds and return rates of captive-reared chicks to the breeding grounds were significantly lower than those of wild chicks. Captive-rearing is considered to be an emergency measure for this species, thus priority management methods should include water management, predator exclosures, clutch re-location and public education.