Movement analysis of free-grazing domestic ducks in Poyang Lake, China: a disease connection

Abstract

Previous work suggests domestic poultry are important contributors to the emergence and transmission of highly pathogenic avian influenza throughout Asia. In Poyang Lake, China, domestic duck production cycles are synchronized with arrival and departure of thousands of migratory wild birds in the area. During these periods, high densities of juvenile domestic ducks are in close proximity to migratory wild ducks, increasing the potential for the virus to be transmitted and subsequently disseminated via migration. In this paper, we use GPS dataloggers and dynamic Brownian bridge models to describe movements and habitat use of free-grazing domestic ducks in the Poyang Lake basin and identify specific areas that may have the highest risk of H5N1 transmission between domestic and wild birds. Specifically, we determine relative use by free-grazing domestic ducks of natural wetlands, which are the most heavily used areas by migratory wild ducks, and of rice paddies, which provide habitat for resident wild ducks and lower densities of migratory wild ducks. To our knowledge, this is the first movement study on domestic ducks, and our data show potential for free-grazing domestic ducks from farms located near natural wetlands to come in contact with wild waterfowl, thereby increasing the risk for disease transmission. This study provides an example of the importance of movement ecology studies in understanding dynamics such as disease transmission on a complicated landscape.

Keywords:

• domestic poultry
• disease transmission
• dynamic Brownian bridge movement model

Acknowledgments

We thank the poultry farmers of the Poyang Lake region for collaboration on this study. The use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Institutes of Health [NIH 1R01AI101028-01A1]; United States Geological Survey; National Aeronautics and Space Administration Wild–Domestic Duck Interface and H5N1 Transmission (NASA) Public Health Program [NNX11AF66G]; National Science Foundation – National Institutes of Health – Ecology of Infectious Diseases program; United Nations Food and Agricultural Organization; National Institutes of Health – Fogarty International Center [R01-TW007869].