Augmenting Small Populations of Plovers: An Assessment of Cross‐Fostering and Captive‐Rearing

This study compared the growth and behavioral development of parent‐reared, cross‐fostered, and captive‐reared Killdeer (Charadrius vociferus) chicks. Common species were used to test these techniques for possible application to rare endangered forms. Parent‐reared chicks were raised naturally in the wild, cross‐fostered chicks were raised by Spotted Sandpipers (Actitis macularia) in the wild, and captive‐reared chicks were raised in captivity by humans. Both hatching and fledging success were significantly increased by captive‐rearing, and cross‐fostering produced approximately the same number of fledged young as natural parent‐rearing. Captive‐reared Killdeer chicks spent more time resting and less time feeding and stayed closer to siblings than cross‐fostered or parent‐reared chicks; these behavioral differences were not seen after release to the wild. Growth rates among the three groups were similar. All of the young Killdeer responded to Killdeer alarm calls. There was no evidence that captive‐reared and cross‐fostered Killdeer were negatively affected by their early experiences. Captive‐rearing is a viable management technique for augmenting small populations of endangered shorebirds, such as the Piping Plover (Charadrius melodus). It is recommended over cross‐fostering because captive‐rearing is more flexible as a technique, produces more young, does not affect another species, and does not produce potential imprinting problems.