Modelling the impacts of agriculture in mixed-use landscapes : A review and case study involving two species of dabbling ducks / David J. Lieske, Megan MacIntosh, Lee Millet, Soren Bondrup-Nielsen, J. Bruce Pollard, Glen Parsons, Nic R. McLellan, G. Randy Milton, Frances MacKinnon, Kevin Connor, and Lauren K. Banks.
Material type:
TextSeries: Landscape Ecology. 33(1): 35-57 Publication details: 2018Description: illustrations ; 28 cmLOC classification: - LIE
| Item type | Current library | Collection | Call number | Status | Date due | Barcode |
|---|---|---|---|---|---|---|
Electronic Journal
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IWWR Supported Research | Non-fiction | LIE (Browse shelf(Opens below)) | Available | 16948 |
Includes bibliographical references (pages 55-57).
Context This study synthesizes evidence from three
separate surveys of American Black Duck and Mallard
breeding habitat usage to quantify the effects of
agriculture at the landscape scale.
Objectives To assess duck breeding activity in
agricultural landscapes within the Canadian maritimes
in order to measure the overall impact of agricultural
land use, the response to particular agricultural
activities, and the influence of landscape
configuration.
Methods Models, constructed using a long-term
census (SURVEY1), were used to predict habitat
selection for two other independent surveys (SURVEY2,
SURVEY3). Predictions incorporated information
about wetland area and diversity, as well as
anthropogenic factors, allowing subsequent analyses
to focus on the remaining residual error attributable to
agricultural effects.
Results SURVEY2 results demonstrated that the
proportion of active agriculture is an important
indicator of the severity of human disturbance,
yielding threshold estimates of 39% for Mallards and
60% for Black Ducks, with an overall average of 50%.
Agricultural conversion beyond these thresholds
deterred breeding ducks independently of other factors.
SURVEY3 land cover information demonstrated
that the presence of cropland intensified this deterrence
effect, even at levels as low as 10%. Woodland
cover (in excess of 30%) was important for both
species, but its configuration was not.
Conclusions In addition to quantifying threshold
effects, this study reaffirms that woodland is an
important part of the maritime landscape matrix, and
contributes positively to habitat diversity in mixed use,
moderate intensity agricultural regions. Wetland
restoration in agricultural landscapes should monitor
and promote less crop-intensive, mixed-use practices.