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WOS 2010 ~ ABSTRACTS p. 26
density were similar between nest sites and random sites. These habitat characteristics are typical at sites where
forest thinning and prescribed fire are used to manage Red-cockaded Woodpecker habitat. We recorded 371 prey
deliveries (males = 195, females = 176) to nest sites by breeding pairs. Most vertebrate prey was delivered by males
(86%), with green anoles (Anolis carolinensis) being the most common prey item (n = 104). Females delivered
mostly invertebrates (88%), and grasshoppers were the most common prey item (n = 54).
43 Influence of seeded, exotic grasslands on wintering birds in mixed-grass prairie. Timothy J. O’Connell and
Andrew D. George, Dept. Natural Resource Ecology and Management, Oklahoma State Univ., Stillwater, OK,
74078.
Millions of hectares of U. S. cropland have been converted to seeded grasslands through enrollment in the
Conservation Reserve Program (CRP) since the 1980s. The majority of those lands have been seeded with exotic,
invasive Old World bluestems (OWB) that are now abundant CRP fields and in managed hayfields. In the U.S.
Southern Plains, several species of conservation priority winter in grasslands; the use of OWB by these species has
not been investigated. We surveyed 6 fields of native grasses and 6 fields of OWB monoculture during two winters
(2008–2009) in Oklahoma to test the hypothesis that richness, abundance of target species, and avian conservation
value was similar between the two types of grass cover. Transect surveys revealed 31 species in the fields over the
two seasons, of which 16 occurred exclusively in native grass fields and 4 occurred exclusively in OWB fields.
Despite these differences, neither mean richness nor diversity differed between the two types of fields. Conservation
value, when weighted by abundance, was significantly different, and higher, in CRP fields. Smith’s Longspur,
Savannah Sparrow, Northern Harrier, and Short-eared Owl were more abundant in OWB fields; American Tree and
Song sparrow were more abundant in native grass fields. Forbs were more abundant in native grass fields, but other
vegetation structure variables were similar between field types. For select species, OWB monocultures may provide
suitable overwintering habitat, although the potential for survivorship to be reduced in these fields remains to be
examined.