A time activity budget of American Oystercatchers (Haematopus palliatus) breeding in Texas

ABSTRACT We developed diurnal time activity budgets to quantify parental behavior of American Oystercatchers (Haematopus palliatus) breeding on the Texas Coast from February to July of 2013 and 2014. We conducted focal animal observations on breeding pairs for two reproductive periods: incubation and chick-rearing. We conducted observations on 60 nests and 38 broods for a total of 1,242 observational hours. American Oystercatchers predominantly engaged in incubation (52%), resting (16%) and self-maintenance (10%) during the incubation period. They predominantly engaged in resting (35%) and vigilance behaviors (29%) during chick-rearing. Agonistic behavior increased by 2% when adults were rearing chicks. We determined that breeding behavior was primarily partitioned between reproductive, self-maintenance, and vigilance behaviors. The life history of American Oystercatchers in the Gulf Coast region was poorly understood until recently, and this study provided insight on activity patterns and local factors i...