Climate Change Enhances the Potential Impact of Infectious Disease and Harvest on Tropical Waterfowl

• Published in: Biotropica 2009-07, Vol.41 (4), p.414-423
• Main Authors: Traill, Lochran W., Bradshaw, Corey J. A., Field, Hume E., Brook, Barry W.
• Format: Article
• Language: English
• Subjects: Animal diseases; Animal, plant and microbial ecology; Anseranas semipalmata; Applied ecology; avian disease; Biological and medical sciences; Climate change; Climatology. Bioclimatology. Climate change; Conservation, protection and management of environment and wildlife; Disease models; Disease outbreaks; Earth, ocean, space; Epidemiology; Exact sciences and technology; External geophysics; Fundamental and applied biological sciences. Psychology; Geese; General aspects; global warming; Infectious diseases; Magpies; Meteorology; Mortality; population viability analysis; Reviews; tropical Australia; Waterfowl
• ISSN: 0006-3606; 1744-7429
• DOI: 10.1111/j.1744-7429.2009.00508.x

Global warming exacerbates threats to biodiversity as ecological systems shift in response to altered climatic conditions. Yet the long-term survival of populations at direct risk from climate change may also be undermined by local factors such as infectious disease or anthropogenic harvest, which leave smaller and more isolated populations increasingly vulnerable to the rapid pace of global change. We review current and future threats to an exemplar tropical waterfowl species, magpie geese Anseranas semipalmata, and focus on the potential synergies between infectious diseases, harvest, and climate change. We outline viral, bacterial, and fungal pathogens likely to cause disease in geese, and give mention to parasites. Further, we elaborate on a previously developed, spatially explicit population viability model to simulate demographic responses to hunting and novel or enhanced disease outbreaks due to climate change. With no harvest, the simulated disease epizootics only threatened metapopulation viability when both mortality rate was high and outbreaks were regular (a threshold response). However, when contemporary site-specific harvest is included as an additive impact, the response to disease severity and probability was linear. We recommend field research to test these hypotheses linking drivers of waterfowl population decline to disease–climate change interactions.