Pine Siskin Salmonellosis Outbreak, Winter 2020-2021

What to Do If You Find A Sick Bird in Your Yard

If you find sick or dead birds in your yard, please contact your local wildlife rescue center straightaway. If you are able to capture the ill or deceased individuals, do so promptly and bring them to your local wildlife rescue for treatment and/or to help remove the disease from your local environment. You can also report individual mortality and mortality events to California Fish and Wildlife, here, to help us and the state track the spread of disease.

Remove and thoroughly clean all seed-feeders and birdbaths immediately, following our Songbird-Safe Bird Feeding Guides below. Leave your feeders and baths down for a minimum of 3-4 weeks. This allows your local birds to redistribute naturally into the environment, lowers the risk of congregation, and therefore, lowers the spread of the disease. However, in light of the severity of the current Salmonellosis Outbreak, The Bird Rescue Center strongly recommends you remove all seed-feeders and birdbaths from your yard until late spring, when Pine Siskins will be migrating north again for the breeding season.

Birds existed long before the invention of birdseed. While many of us love supporting our local wildlife with supplement seed-feeders, these feeders are currently posing a life-threatening risk to our feathered neighbors.

Pine Siskins, and other “feeder-species”, naturally arrive in an area, disperse, deplete all available resources, then move on. As such, they are rarely in close contact with one another while foraging and do not spend much time in one location, which helps keep the population healthy. Unfortunately, our feeders prevent this natural behavior, encouraging not only the congregation of birds in close contact, but keeping them in a single environment for a prolonged period. This combination becomes deadly when there is a disease circulating.

The very best way we can help stop the spread of the Salmonellosis Outbreak and reduce avian mortality is to remove bird baths and feeders, allowing wild birds to distribute and feed more naturally on native vegetation across the landscape.

Irruption & Salmonellosis Outbreak

California is currently experiencing a Salmonellosis (“Salmonella”) Outbreak. Salmonellosis is a fatal bacterial infection that rapidly spreads through populations of wild birds via feces-contaminated food and water. Most often, Salmonellosis Outbreaks originate where birds flock to feeders or baths. Infected individuals will appear lethargic, puffed/fluff-up, with eyes partially closed; on occasion eyes may also appear swollen, red, or irritated.

Pine Siskins – tiny, heavily streaked, yellow-accented finches – are especially susceptible to Salmonellosis. Pine Siskins occur naturally in small populations across Sonoma County; however, this winter we are seeing huge numbers migrating in. This mass-migration is referred to as an “Irruption Year”, a natural phenomenon driven by fluctuations of available resource. This winter, there is a shortage of tree seeds across Canada’s boreal forest (the normal wintering grounds for Pine Siskins), causing siskins to ‘irrupt’ south in search of food. According to a recent article from The National Audubon Society, this winter’s irruption is one of the largest in recorded history. In fact, siskins have even been reported migrating at night – a very odd spectacle for a diurnal species.

Not only are Pine Siskins especially susceptible to the disease, they are also carriers of Salmonellosis, spreading it throughout the environment. Therefore, we often see Salmonellosis Outbreaks correlated with irruption years, which is what is occurring now. If the disease persists in the environment for long enough, it will eventually spread from Pine Siskins to goldfinches, other finch species, and beyond, penetrating deep into the avian community.

To date, The Bird Rescue Center is being hit hard by the Salmonellosis Outbreak. Since mid-November, we have been fielding dozens of calls every day about sick Pine Siskins and Salmonellosis. Our hospital has received more than double our average number of intakes for this time of year, with Pine Siskins serving as over 40% of all intakes. Unfortunately, we are now seeing the disease in American Goldfinches, Lesser Goldfinches, House Finches, and Purple Finches. As we enter into the peak of the Salmonellosis Outbreak, some days Salmonellosis is the entirety of our new caseloads, with well over two dozen cases a day.

Our local, wild avian community is being hit hard by a Salmonellosis Outbreak and they need our help to survive!

Risk of Salmonellosis to Humans and Domestic Animals

Salmonellosis is a zoonotic disease, meaning it can be transferred from animals to humans, and vice versa. In avian species, Salmonellosis is often fatal; however, in mammalian species, such as ourselves and our 4-legged companions, Salmonellosis often presents as “food poisoning”. Common symptoms include acute abdominal pain, diarrhea (sometimes containing blood), vomiting, weight loss, or fever. Severity of symptoms can vary widely, but humans/mammals infected with the disease may not get sick at all and/or many that do become symptomatic will require no medical treatment beyond rest and hydration.

If you find a sick bird, please do not hesitate to help it! If you are diligent about washing your hands after you capture the animal and/or handle potentially contaminated equipment, there is a very small risk of infection. Additionally, the use of small latex-style disposable gloves can be worn to eliminate direct contact.

That said, parents of young children and/or owners of free-roaming cats or outdoor dogs, please take note. Your loved ones are at risk of contracting Salmonellosis if they have free access to potentially infected equipment (i.e., feeders and baths) or dropped seeds. Furthermore, pets – primarily free-roaming cats – that predate upon infected wild birds can contract the bacteria. These are some of many good reasons to always keep your cats indoors or contained in a catio, as well as to follow our recommendation of fully removing your feeders and baths if you find a sick bird in your yard. Your local wildlife, pets, and loved ones will thank you for keeping their safety in mind!

Year-Round, Songbird-Safe Feeding and Bath Guidelines
Based on: News from our Nest, Veronica Bowers, Native Songbird Care & Conservation, December 2020

First, please consider the use of native vegetation to support, feed, and sustain local wildlife. Native plants provide shelter, seeds, berries, nectar, and insects – all of which are vital resources for wild birds. They also promote more natural, safe, and healthy foraging habits, reducing the risk of disease spread through your yard.

If you choose to also provide supplemental feeders and/or birdbaths, it is critically important you clean them at least once a week, all year-round.

Bird Feeder Cleaning Instructions:

• • All feeders should be cleaned and disinfected at least once per week, year-round.
    Tip: Keep duplicates of each type of feeder so you can place a fresh one out while the other is being cleaned.
  • Safely discard any remaining food into your compost bin or trash
    This should include raking up spilled seed or debride below your feeders. This helps improve overall cleanliness; reduces risk of children, domestic animals, or other wildlife contacting potentially contaminated seeds; and reduce the presence of rodents foraging on dropped seed.
  • Clean: Scrub feeders inside and out with warm, soapy water, then thoroughly rinse with water.
  • Disinfect: Soak feeders in a warm 9:1 bleach solution for 10-15 minutes.
    Alternatively, use bleach solution in a spray bottle to coat feeders inside and out. Let sit for 10-15.
    To make the bleach solution, mix 9 parts water with 1 part bleach (i.e., 9 cups of water to 1cup of bleach, or approximately 1 gallon water to 1.75
    cups bleach, etc.).
  • Rinse thoroughly with water, then allow feeders to fully air dry before re-filling and re-hanging.

Bird Bath Cleaning Instructions:

• • All baths should be emptied and refilled with fresh water on a daily basis, year-round.
  • All baths should also be cleaned and disinfected once per week following the same procedures as cleaning bird feeders.

Keep Yourself Safe:

• Wear gloved to protect your skin from direct contact with bleach or potential pathogens.
• Wear a mask to prevent accidental ingestion or inhalation of splash back or aerosolized particles.
• Always wash your hands thoroughly with soap and warm water after contact with sick or dead birds and/or dirty feeders and baths.

References:

• Native Songbird Care & Conservation – News from our Mews, December 2020
• Canadian Wildlife Health Cooperative – Avian Salmonellosis Fact Sheet
• National Audubon Society – Pine Siskin Irruption
• California Fish and Wildlife – Salmonellosis Overview
• California Fish and Wildlife – Bird Feeders and Birdbaths