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Effects of rearing treatment on the behavior of captive whooping cranes (Grus americana)

M.D. Kreger·I. Estevez·Jeff S. Hatfield·G.F. Gee
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Abstract

Small founder populations of whooping cranes are managed to maximize egg production for the purpose of reintroducing young to the wild. This results in an excessive number of hatched chicks that cannot be naturally reared by parents. Hand-rearing techniques have been developed to raise the additional hatches. However, hand rearing may affect the behavior of the birds and their chances of survival later in life. The objectives of this study were to determine the impact of rearing practices on the behavior of whooping crane chicks. The birds were reared under three commonly used rearing techniques: parent reared (PR), hand reared (HR), and hand reared with exercise (HRE). Fifty-six whooping crane chicks were observed by focal animal sampling from hatch to 20 weeks of age. During these observations, occurrences of comfort behavior, aggression, foraging, nonvigilance, sleep, vigilance, and other types of behavior were collected. Data were analyzed using mixed models repeated measures analysis of variance (ANOVA). Behavior was affected by rearing treatment, age, and time of day. PR birds spent more time being vigilant than HR and HRE birds. An inverse correlation was found between percentage of time foraging and vigilant (r = -0.686, P < 0.0001). However, there were no differences in the behavior of birds reared in HR or HRE programs.

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M.D. Kreger, I. Estevez, Jeff S. Hatfield, G.F. Gee. 2004. Effects of rearing treatment on the behavior of captive whooping cranes (Grus americana). https://doi.org/10.1016/j.applanim.2004.07.005

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