The impact of cattle grazing regimes on tropical savanna bird assemblages

Neilly, Heather, and Schwarzkopf, Lin (2019) The impact of cattle grazing regimes on tropical savanna bird assemblages. Austral Ecology, 44 (2). pp. 187-198.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: https://doi.org/10.1111/aec.12663
2


Abstract

Globally, agricultural land use is implicated in the decline of avifauna. In rangelands (areas used for livestock grazing), bird community responses to grazing can be complex, species-specific and scale dependent. A greater understanding of bird responses to grazing will lead to more meaningful management recommendations. We tested the hypothesis that foraging height predicts bird species' responses to grazing, such that species using lower vegetation strata are most likely to respond to the impacts of livestock grazing. We examined the response of a tropical savanna bird community to four grazing strategies at a long-term grazing trial in northern Australia. We predicted that ground-foraging guilds would be more responsive to grazing treatment than foliage- or aerial-foraging guilds. We analysed the bird community assemblage using generalised linear mixed models and examined individual species' abundance in relation to microhabitat variables. We found that while ground-foraging guilds were more responsive to grazing treatment, individual species dynamics within a foraging guild could be contradictory. For example, the red-backed fairy-wren decreased in abundance with increased grazing and was positively associated with grass and shrub (Carissa ovata) cover, whereas Australian magpies increased in abundance in the most heavily grazed paddocks. In general, the responses of bird species to grazing were more pronounced in guilds that forage closer to the ground, but whether the responses were positive or negative was driven by bird species ecology. Measures examining the responses of individual species are more useful than assemblage measures (such as richness) to describe the impacts of anthropogenic disturbance such as grazing.

Item ID: 57907
Item Type: Article (Research - C1)
ISSN: 1442-9993
Keywords: avifauna, bird community, community ecology, livestock grazing, microhabitat, rangelands
Copyright Information: © 2018 Ecological Society of Australia.
Funders: Queensland Department of Agriculture and Fisheries, Meat and Livestock Australia, Australian Government, Holsworth Wildlife Research
Projects and Grants: Australian Postgraduate Award
Date Deposited: 10 Apr 2019 07:37
FoR Codes: 05 ENVIRONMENTAL SCIENCES > 0502 Environmental Science and Management > 050202 Conservation and Biodiversity @ 100%
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page