Activity patterns and spatial use of facility by a group of captive female manatees (Trichechus manatus latirostris)

As a means to compare and contrast to free-ranging Florida manatees, we examined the behavior and movement patterns of nine adult-female captive manatees at Homosassa Springs Wildlife State Park (HSWSP). HSWSP has a unique manatee exhibit that consists of a natural river and a man-made pool. Because the manatees are exposed to a natural environment including natural food resources, the study of various aspects of behavioral and physiological parameters of the captive manatees is especially valuable with this group. We determined activity pattern and spatial use of the facility by manatees over three allotted periods of a day (noon, mid-afternoon, and late-afternoon) and three seasons (winter, spring, and summer). Behavioral strategies of the manatees were: 1) to remain "inactive," probably to conserve energy, during the day while the park provisioned food; 2) to alter locations during the course of the afternoon, apparently with the direction of the sun, possibly to assist with thermoregulation; and 3) to change location seasonally where and when food resources became abundant, showing a strong interest in natural vegetation as it became available. Spatial use and activity pattern of the HSWSP captive manatees apparently were influenced by energy constraints and nutrient intake by provisioned food availability over the day and natural vegetation over the study period. The behavior of the female group of manatees may have been affected by the single-sex living arrangement. In addition, these manatees are subject to a largely invariable temperature (ca. 23 degrees C) that may have created thermal stress and immunological suppression over time. This study demonstrated that for these captive manatees the activity patterns and spatial use were comparable to that of free-ranging manatees in relation to the availability of food resources.