Avian Community Response to Grazing Intensity on Monoculture and Mixed Florida Pastures
Issue Date
2010-03-01Keywords
abundanceavian-habitat relationships
biodiversity
guild
heterogeneity
migratory birds
vegetation structure
Metadata
Show full item recordCitation
Willcox, E. V., Tanner, G. W., Giuliano, W. M., & McSorley, R. (2010). Avian community response to grazing intensity on monoculture and mixed Florida pastures. Rangeland Ecology & Management, 63(2), 203-222.Publisher
Society for Range ManagementJournal
Rangeland Ecology & ManagementAdditional Links
https://rangelands.org/Abstract
Monoculture and mixed pastures in Florida provide habitat for a variety of resident and migratory bird species. The objectives of this study were to investigate the effects of grazing on vegetation structure and bird species richness and abundance in grazed monoculture and mixed pastures. Study pasture units were subject to four cattle grazing intensities: 0 = nongrazed (control), 15 = low, 20 = medium, or 35 = high animal units (AU) per pasture unit (no cattle, 1.3, 1.0, and 0.6 ha AU-1, on monoculture pastures and no cattle, 2.1, 1.6, and 0.9 ha AU-1, on mixed pastures). Monoculture pastures displayed a greater decrease in spatial heterogeneity of the vegetative community in the presence of grazing than mixed pastures. An increase in grazing intensity led to declines in total avian species richness and abundance and species richness within short-distance migrant, neotropical migrant, and permanent resident guilds on monoculture pastures. Declines in total species richness and abundance and neotropical migrant guild species richness and abundance were observed on mixed pastures subject to increasing grazing intensity. However, species richness within short-distance migrant and urban guilds and abundance within the grassland guild increased on this pasture type in the presence of grazing. Loss of spatial heterogeneity typically results in a lack of suitable habitat for birds that occupy the extremes of the vegetation structure gradient. This can lead to a loss of species richness and abundance. For the majority of avian guilds, a low grazing intensity of 1.3 ha AU-1 and 2.1 ha AU-1 on monoculture and mixed pasture, respectively, is recommended to maintain abundance. However, these grazing intensities may result in declines in species richness. Ultimately, if a range of avian species are to be supported on monoculture and mixed pastures, spatial heterogeneity of plant structure and composition must be maintained.Type
textArticle
Language
enISSN
0022-409Xae974a485f413a2113503eed53cd6c53
10.2111/REM-D-09-00092.1