The rise of highly pathogenic avian influenza (HPAI) in B.C. has yet to show any signs of slowing down. Positive cases have been confirmed in the Lower Mainland, Vancouver Island, Interior and North regions. This includes birds like great horned owls, bald eagles, great blue herons, ducks and geese, and even crows.
During this fall migration season, birds gathering in large groups can be problematic for the spread of HPAI – an effect that is particularly apparent for snow geese in the Richmond and Delta area.
“The number of confirmed positive cases is just the very tip of the iceberg,” says Andrea Wallace, manager, wild animal welfare, “The number of suspected cases – alive or deceased – far exceeds the capacity to test the animals. In addition, many animals that pass away in the wild are never recovered.”
The BC SPCA is continuing to advise the temporary removal of seed and suet bird feeders to help discourage unnecessary large gatherings that may facilitate the spread of the disease.
Which animals are affected?
Although waterfowl (including ducks, geese and gulls) and raptors (eagles, hawks and owls) are highest risk, avian influenza viruses can infect all avian species. Wild birds, especially waterfowl, are natural reservoirs of influenza viruses. They are not normally affected by the disease, but can still transmit it to other birds. The H5N1 strain is considered highly pathogenic, causing severe illness and death in birds.
Pet birds can also be infected by avian influenza, and HPAI has been detected in mammals including rats, mice, weasels, ferrets, pigs, cats and dogs.
In Canada, B.C. is second only to Alberta for the highest number of birds affected at poultry farms, resulting in mass mortality.
How does the virus spread?
The virus is shed by infected birds through feces and respiratory secretions and is very resilient – the virus can survive in the environment for several months and continue to infect other birds. HPAI may also persist on clothing and footwear creating further transmission risk. If you visit an area where birds congregate or are in contact with wild birds, be sure to clean and disinfect your footwear and wash your clothing thoroughly.
Bird feeders facilitate the spread of the disease by encouraging unnatural congregations of birds and attracting other wildlife including predators and rodents. Fallen seed is also an especially bad source of disease – when birds feed from the ground, they are also exposed to droppings that accumulate below a feeder. The presence of bird feeders and baths can also increase the risk of transmitting the virus between nearby animals like backyard chickens or turkeys. Do not keep bird feeders or create duck ponds close to poultry barns – this will attract wild birds and create more opportunities for disease transmission.
The virus can spread to birds through contact with infected poultry and poultry products, or through contact with contaminated manure, litter, clothing, footwear, vehicles, equipment, feed and water. On rare occasions, this virus can cause disease in humans that have close contact with infected birds, or heavily contaminated areas.
If you see a sick bird
Sick birds may appear lethargic, unusually “fluffed up”, have nasal discharge, coughing and/or sneezing, diarrhea, or have excessively watery eyes or swelling of the head, neck and eyes. Contact the BC SPCA at 1-855-622-7722 for advice about sick birds or for help finding your local wildlife rehabilitation centre.
Report sightings of sick or dead wild birds to the B.C. Wild Bird Mortality Investigation Protocol & Avian Influenza Surveillance Program (PDF) at 1-866-431-BIRD (2473). If the report is assessed to require further investigation, guidance will be provided on a case by case basis. Please do not bring deceased birds to a wildlife rehabilitation centre or veterinary clinic as they will not be able to test for the disease.
Resources:
- B.C. Wildlife Health
- Dashboard: Highly pathogenic avian influenza – wild birds
- Map: Avian influenza zones
- Fact sheet: Avian influenza
- Precautions for bird banders, Aviculturists and wildlife rehabilitation centres
- Government of Canada – status of ongoing H5N1 response
More information on bird feeders
Help curb this serious disease by removing your bird feeders and emptying bird baths as well as monitoring for any signs of sick birds in your area. Outside of disease outbreaks, the BC SPCA generally recommends only providing bird feeders in winter between October and March. In the spring and summer months, there is lots of natural food for birds. Get the facts on backyard bird feeding.
“Now is a good time to start planning bird-friendly plants for spring,” says Wallace, “Native plants are the safest way to attract birds to your yard, and help other native wildlife too.” Learn more about making a bird-friendly backyard.
Provide water sources with caution. Well-maintained bird baths and running water sources are considered relatively low-risk for HPAI. Water sources must be emptied, cleaned, and refilled regularly. If you see any signs of sick birds in your yard, empty the water sources and discontinue use immediately.
What about hummingbird feeders?
Hummingbird feeders are not without risk but pose the lowest risk because they are species-specific and have a more limited group of birds visiting them. However, this is a good reminder to regularly change the nectar in and clean hummingbird feeders to prevent deadly fungal outbreaks. Learn how and when to change the hummingbird nectar solution, how to clean your hummingbird feeder, and how to keep hummingbirds safe in winter. And remember, if you see sick birds at your feeder, take it down right away!