Snow geese migration picture
Updated: March 29, 2023

Protect Your Farm from Bird Flu:  Tips for Managing Wild Birds During Migration Season

     Migrant birds traverse across the United States two times a year; they travel from the North to South in the late summer through fall and back to the North in late winter through spring. Waterfowls, shorebirds, gulls, and terns are among these migrant birds and are known to have the avian influenza (Bird Flu) virus naturally. Nesting grounds and stop-over sites of these birds are mixing vessels of the Flu virus, where new viral variants arise from the intermixing of birds from wide geographical regions. Among the four major migratory pathways, the Atlantic flyway, which straddles across the eastern coast of North America and South America, plays an important role in the epidemiology of Bird Flu. The spread of recent highly pathogenic Bird Flu, which is of Eurasian lineage, is believed to have occurred through infected migratory birds traversing across the Atlantic from Europe.

     Spring migration of these birds usually lasts from February through April and can potentially lead to widespread outbreak across the migratory pathways. Domestic poultry, including commercial poultry and backyard flocks, are at great risk of Bird Flu through feed, equipment, and personnel contaminated by droppings and other secretions from these migratory birds. The risk of Bird Flu has been further heightened by the spread of the H5N1 subtype of AIV prevalent in Europe and Asia before emerging in North America in late 2021. Also, the recent spate of this flu outbreak in South America, which had been free of HPAI, has rung a bell of alarm in poultry farmers, public health officials, and animal health personnel alike across the nation.   

    The recent 2022 outbreak caused primarily by H5N1 subtype of the virus, has been recorded in poultry across 47 of the United States. The outbreak has been the most severe since the 2014-2015 outbreak, causing the loss of more than 53 million birds. Unlike previously reported farm-farm spread of infection, this recent outbreak is driven primarily by movement of wild migrant birds. Unlike the 2014-2015 outbreak, which was killed by the bright sunshine and warm temperature of summer, the new virus persisted through summer in wild birds and the infection resurged afterwards in the cooler and wetter months of winter. Also, two human cases of bird flu have been reported this time caused by this prevailing virus. However, these two cases do not change the human risk assessment for the general public, which CDC considers to be low.

     Due to the seasonal pattern shown by Avian Influenza, the number of outbreaks in poultry flocks is expected to increase in the coming days. So, stringent biosecurity measures outlined by the USSDA APHIS and NPIP are recommended to apply on the farm to check the spread of infection. The routine farm biosecurity measures like the use of clean clothing before entering the bird area, disinfection of vehicle tires before entry onto the farm, bird proofing the poultry farm, All-In All-Out system, etc., can be effective to combat Bird Flu.  Beside these measures, simple wildlife management practices like the following can potentially reduce the risk of Bird Flu on your farm.

  1. 1) Reducing the attraction of wild birds through the use of frightening devices (sirens, flash lights, scare-crows, bird distress calls, etc.)

  2. 2) Removing standing water that can attract thirsty wild birds

  3. 3) Managing risks at ponds and water basins

  4. 4) Promptly cleaning feed or grain spillover

  5. 5) Covering farm generated wastes (waste feed, dead birds, egg shells, litter)

  6. 6) Removal of trees which can be potentially used by wild birds for shelter or for food

 

  1. BirdCast Migration picture
    Figure 2: BirdCast, migration forecast map; night of March 23, 2023. Cornell Lab of Ornithology and Colorado State University

     Farmers who are concerned about wildlife intruding areas near their poultry facilities can contact their USDA-APHIS Wildlife Services’ state office at 1-866-487-3297. They can also visit the USDA website at www.usda.gov/avianinfuenza to learn more about avian influenza and recommended biosecurity practices (as well as our own Maryland Poultry website with videos at extension.umd.edu/poultry). Wild-bird migration forecast tools provided by BirdCast can help producers prepare for future risk.

     Moreover, reporting suspicious disease which resembles the symptoms of Bird Flu in domestic poultry, pet birds, game birds, and other wild birds can assist in the surveillance of AI. Together these biosecurity measures, alongside the active surveillance program from animal health authorities, can mitigate the risk of Bird Flu to a large extent.

References and useful resources:

1. Wildlife Damage Management Technical Series http://bit.ly/408VPF6
2. To track live bird migration maps over your area https://birdcast.info/
3. Biosecurity Guidelines against Avian Influenza https://bit.ly/3FDIMDp
4. Manage Wildlife To Prevent Avian Influenza https://bit.ly/ManageWildlifeToPreventflu
5. 2022-2023 Detections of Highly Pathogenic Avian Influenza http://bit.ly/3ncTFpq

Acknowledgment:

This work is supported by the Smith Lever Special Needs Competitive Grant, project grant number 2022-41210-38062, from the USDA National Institute of Food and Agriculture and the University of Maryland, College Park.