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11.
Effects of forest patch size on avian diversity 总被引:10,自引:2,他引:8
Nancy E. McIntyre 《Landscape Ecology》1995,10(2):85-99
The effects of landscape patchiness on the diversity of birds of the Georgia Piedmont were investigated during 1993. Birds were sampled along line transects within relatively large (10–13.25 ha) and small (less than 3.25 ha) forest patches located within nonforest agricultural landscapes. Patterns of habitat use in these patches were compared to those in contiguous forest patches larger than 13.25 ha. Analysis of variance revealed significant differences in diversity between large and small woodlots and between contiguous and fragmented landscapes, especially in terms of the numbers of edge and interior species and winter-resident, summer-resident, and year-round birds observed. 相似文献
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Carissa Embury-Hyatt Rosemary Postey Tamiko Hisanaga Lynn Burton Kathleen Hooper-McGrevy Leanne McIntyre Kevin Millar John Pasick 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(9):998-1002
In March 2011, rabbit hemorrhagic disease (RHD) was suspected in a 1-year-old male neutered lop-eared rabbit that had acute onset liver failure. Gross pathology, histopathology, immunohistochemistry, partial nucleic acid sequencing and phylogenetic analysis of the major capsid protein (VP60) and animal inoculation studies all supported this diagnosis making it the first confirmed case of RHD in Canada. 相似文献
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Marsha Taylor Lorraine McIntyre Mark Ritson Jason Stone Roni Bronson Olga Bitzikos Wade Rourke Eleni Galanis Outbreak Investigation Team 《Marine drugs》2013,11(5):1669-1676
In 2011, a Diarrhetic Shellfish Poisoning (DSP) outbreak occurred in British Columbia (BC), Canada that was associated with cooked mussel consumption. This is the first reported DSP outbreak in BC. Investigation of ill individuals, traceback of product and laboratory testing for toxins were used in this investigation. Sixty-two illnesses were reported. Public health and food safety investigation identified a common food source and harvest area. Public health and regulatory agencies took actions to recall product and notify the public. Shellfish monitoring program changes were implemented after the outbreak. Improved response and understanding of toxin production will improve management of future DSP outbreaks. 相似文献
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L McIntyre 《New Zealand veterinary journal》2013,61(1-2)
Extract Early last year, shortly after taking office as Minister of Agriculture and Fisheries, I initiated a survey by my Ministry of the state of the livestock industry. 相似文献
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Daniel R. Goethel Katelyn M. Bosley Brian J. Langseth Jonathan J. Deroba Aaron M. Berger Dana H. Hanselman Amy M. Schueller 《Fish and Fisheries》2021,22(1):141-160
Understanding spatial population structure and biocomplexity is critical for determining a species’ resilience to environmental and anthropogenic perturbations. However, integrated population models (IPMs) used to develop management advice for harvested populations have been slow to incorporate spatial dynamics. Therefore, limited research has been devoted to understanding the reliability of movement parameter estimation in spatial population models, especially for spatially dynamic marine fish populations. We implemented a spatial simulation–estimation framework that emulated a generic marine fish metapopulation to explore the impact of ontogenetic movement and climate‐induced distributional shifts between two populations. The robustness of spatially stratified IPMs was explored across a range of movement parametrizations, including ignoring connectivity or estimating movement with various levels of complexity. Ignoring connectivity was detrimental to accurate estimation of population‐specific biomass, while implementing spatial IPMs with intermediate levels of complexity (e.g. estimating movement in two‐year and two‐age blocks) performed best when no a priori information about underlying movement was available. One‐way distributional shifts mimicking climate‐induced poleward migrations presented the greatest estimation difficulties, but the incorporation of auxiliary information on connectivity (e.g. tag‐recapture data) reduced bias. The continued development of spatially stratified modelling approaches should allow harvested resources to be better utilized without increased risk. Additionally, expanded collection and incorporation of unique spatially explicit data will enhance the robustness of IPMs in the future. 相似文献
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A new, multi-scaled graph visualization approach: an example within the playa wetland network of the Great Plains 总被引:1,自引:1,他引:0
We employed a sliding-window approach at multiple scales (window sizes and dispersal distances) to calculate seven standard graph-theoretical metrics within a subset of a large, freshwater wetland network. In contrast to most graph analyses, which quantify connectivity at a single (global) scale or at a patch-level scale, a multi-scaled, sliding-window approach provides an assessment that bridges these two approaches to examine patch clusters. As a case study we focused on a subset of a habitat patch network in a ~20,000 km2 area encompassing 2,782 playa wetlands in the panhandle of Texas. Playas are seasonal wetlands of the southern Great Plains of North America that form a network of regional habitat resources for wildlife. The large size of this network meant that global metrics failed to capture localized properties, so we used contour mapping to visualize continuous surfaces as functions of playa density, linkage density, and other topological traits at different window sizes and dispersal distances. This technique revealed spatial patterns in the components (i.e., the network properties of regions of the landscape at a given dispersal scale), with the spatial scale of habitat clustering varying with the size of the sliding window and dispersal distance. Using a tool familiar to landscape ecology (sliding-window methodology) in a novel way (to examine ecological networks at multiple scales), our approach provides a way to represent ecologically determined local-scale graph properties and illustrates how a multi-scaled approach is useful in examining habitat connectivity to investigate graph properties. 相似文献