Laserfiche WebLink
ap <br />3. PIPING PLOVER <br />A. NestinQ <br />Habitats occupied by piping plovers during the nesting season are <br />ecologically and physical-ly similar to those. of the interior <br />least tern (Table 12) (Faanes 1983, Currier et al. 1985, USFWS <br />1987a). The data suggest that piping plovers are more tolerant <br />of vegetation in the nesting area than are interior least terns <br />(Faanes 1983). <br />B. ForaQina <br />The principal difference in foraging strategies between least <br />terns and piping plovers is that the plover eats invertebrates <br />almost'? exclusively; the least'tern primarily eats fish. Most <br />observations of foraging among piping plovers suggest that the <br />bird secures its prey primarily by picking and gleaning on sandy <br />substrates from the wet zones up to dry sand. Following review <br />of the available data, the Biology Workgroup assumed that <br />suitable riverine nesting habitat for piping plovers would also <br />provide suitable riverine foraging habitat. Although piping_ <br />plovers forage at sandpit nesting areas, Lingle (unpubl. da.ta) <br />has observed piping plovers move from sandpits to riverine <br />habitats to forage. <br />4. BALD EAGLE <br />A. Roostina <br />Wintering bald eagle,s often congregate at communal roost sites, <br />in some cases traveling 20 km or more from feeding areas to a <br />roost site (Fisher et al. 1981). The same roosts are typically <br />used every year and-are usually located in areas protected from <br />wind, harsh weather, and human disturbance (Steenhof 1978, Fisher <br />et al. 1981). The use of large, live trees in sheltered areas <br />provides a more favorable thErmal environment and helps to <br />minimize the energy stress er.icountered by wintering birds (USFWS <br />1987a). Communal roosting may help to facilitate food-finding <br />and pair-bonding (Steenhof 1978). The proximity of adequate <br />night roosts to the other habitats required by wintering bald <br />eagles such as hunting perches and feeding sites is important <br />(USFWS 1987a). In some'lacations the absence of a suitable <br />night roost may limit the use of otherwise suitable habitat <br />(USFWS 1987a). Freedom from human disturbance is also important <br />in communal roost site selection (Fisher et al. 1981). Continued <br />human disturbance at a nocturnal roost may cause bald eagles to <br />abandon an area (Hansen et a:L. 1981, Keister 1981).