New research into the movement patterns of waterfowl, including ducks, swans and geese, could help commercial poultry producers better predict and manage the risk of highly pathogenic avian influenza (HPAI).
Claire Teitelbaum, assistant unit leader with the U.S. Geological Survey’s Georgia Cooperative Fish and Wildlife Research Unit and adjunct assistant professor in the Warnell School of Forestry and Natural Resources at the University of Georgia, said the findings point to wild bird habitat management as an underutilized tool in the fight against HPAI.
"The results of this study really highlight that protecting and properly managing habitats for wild birds could be an important part of managing or slowing the spread of highly pathogenic avian influenza with relevance to commercial poultry," she explained.
Where wild birds come from matters
According to the study in Ecology Letters summing two decades of movement data analysis from more than 4,600 waterfowl across 26 species, where wild birds live largely determines how far they travel.
Birds in areas with more varied habitats — like a mix of wetlands, green spaces and urban areas — stayed closer to home, which could mean less opportunity for HPAI to spread to new areas, including commercial poultry farms.
Wild birds are highly tolerant of HPAI, meaning they can be infected with the virus but show few clinical signs. Therefore, “understanding what makes them move can help us predict where they’re going to go and where they’re going to bring these viruses with them,” Teitelbaum said.
"This has the potential to inform things like biosecurity in commercial facilities — to know that this is a high-risk time, so we really need to be extra careful right now," she added.
Habitat management could also play a direct protective role in protecting commercial poultry against HPAI.
For example, during drought conditions, waterfowl are forced to disperse from their normal ranges, potentially carrying the virus and other pathogens into new areas. Maintaining adequate water in lakes and ponds located in key waterfowl habitats during high-risk weather periods could help keep birds concentrated and reduce that dispersal risk.
Non-migratory movements still drive spread
While migration typically dominates conversations about HPAI and wild birds, this study focused specifically on shorter-range, within-season movements and still found meaningful links to virus spread patterns.
That distinction is important, as it expands the window of concern beyond traditional migration periods, Teitelbaum said.
Stronger HPAI spillover
When modeling distances between HPAI detections in wild waterfowl, Teitelbaum included broiler density as a variable and found a relationship, though a relatively weak one. She said the finding supports a growing body of research indicating that spillover and spillback between poultry and wild birds has been more frequent during the current outbreak than seen previously than in previous HPAI outbreaks.
In the future, Teitelbaum hopes to investigate whether extreme weather events trigger the kind of unusual long-distance movements in wild birds that could introduce HPAI into previously unaffected areas — a mechanism she believes may have played a role in the virus's arrival to North America.
To learn more about HPAI cases in commercial poultry flocks in the United States, Mexico and Canada, see an interactive map on WATTPoultry.com.
View our continuing coverage of the global avian influenza situation.
