New Jersey's Wild Bird Die-Off

 

#19,059

The Northern Hemisphere is at - or near - peak avian flu for this winter season, with literally scores of outbreaks being reported on a daily basis.  So much so, that reporting on individual outbreaks has become nearly futile. 

While we get reasonably accurate numbers of poultry lost to HPAI H5, its impact on wild birds and mammals can only be guesstimated. 

A year ago, in Nature Reviews: The Threat of Avian Influenza H5N1 Looms Over Global Biodiversity, we looked at some of those estimates:

An estimated half a billion domestic fowl have died of H5N1 (ref. 4), and this number is rising; mortality in wildlife is more difficult to quantify than in poultry, but the effects are substantial. By mid-2024, H5N1 infections were documented in at least 406 bird and 51 mammal wild species (according to reports on the World Animal Health Information System (WAHIS)), and available reports suggest that multiple millions of wild animal individuals may have died (Fig. 1a).

The most noteworthy mass-mortality events include more than 200,000 wild birds in coastal areas of Peru6; 24,000 sea lions in South America7; 20,500 wild birds in Scotland8; 6,500 Cape cormorants in Namibia9; and 17,400 elephant seals, including >95% of the pups in Argentina10. These figures, however, largely underestimate actual mortalities, owing to a pervasive lack of monitoring, testing and reporting — particularly in inaccessible areas and in disadvantaged countries4,7.

These numbers are now 18 months old, and H5's carnage has only increased since then (see ISIRV: Update on H5N1 Panzootic: Infected Mammal Species Increase by Almost 50% in Just Over a Year). While H5N1 has yet to crack the human code, it is already a devastating pandemic (panzootic) in animals. 

The long-term impact of this loss of biodiversity remains uncertain. By the time we know, however, it will be a fait accompli. 

Last week, in Several States Warn On Contact With Wild Birds/Mammals, we looked at a sampling of recent non-poultry outbreaks across the country. This week, the hot-spot (at least based on media reporting) for avian flu appears to be New Jersey. 

As the following FluTracker's Thread illustrates, over the past few days the NJ Department of Environment has been flooded with reports of hundreds of dead birds (mostly in Snow geese and Canadian geese) littered across the state. 

Credit NJ Fish & Wildlife

What Agencies are Responding to the Outbreak?

The U.S. Centers for Disease Control and Prevention  states that the ongoing nationwide H5N1 outbreak is primarily an animal health issue that poses low risk to the health of the public. The three principal state agencies involved in monitoring and responding to avian influenza are NJDEP Fish & Wildlife, the New Jersey Department of Health, and the New Jersey Department of Agriculture, which provide the following updates:

• Between August 2025 and February 17th,2026, we have confirmed detections in 8 counties (Bergen, Burlington, Middlesex, Monmouth, Salem, Somerset, Sussex and Warren) and a preliminary detection in 5 counties (Atlantic, Cape May, Cumberland, Essex, and Hunterdon).
• The New Jersey Department of Health  continues to closely monitor H5N1 and collaborate with state and federal partners on preparedness and response to H5N1. There are no reports of H5N1 in humans in NJ, but the virus has been detected in multiple domestic cats: H5 Highly Pathogenic Avian Influenza Confirmed in New Jersey Cat 
• The New Jersey Department of Agriculture  reports that there have been confirmed detections in domestic poultry in Hudson, Mercer, Union and Essex Counties.

While tests on these most recent bird deaths are pending, yesterday the Burlington County Department of Health Posted:

The Burlington County Health Department is reminding residents to be aware of the potential spread of Highly Pathogenic Avian Influenza, also known as bird flu, following the discovery of large numbers of dead geese in Hainesport and other South Jersey locations this week.

The Health Department has not been notified of any positive tests confirming the birds died from bird flu, however, officials are treating it as a likely bird flu case.

Residents are encouraged to review avian flu information and guidance on the County Health Department website and follow all recommended precautions. The webpage is at https://www.co.burlington.nj.us/2115/H5N1-Bird-Flu . Information is also posted in County parks.

Among the recommended precautions:

• Avoid contact with wild birds;

• Avoid unprotected contact with wild or domestic birds;

• Report cases of dead or sick wild birds to the NJ Dept. of Environmental Protection at 877-927-6337;

• Report cases of dead or sick domestic birds or livestock to the NJ Dept. of Agriculture at 609-671-6400 or state.veterinarian@ag.nj.gov .

• Pet owners should keep dogs and cats away from areas of high concentrations of geese or geese waste;

• Pet owners who notice signs of illness in their pet bird, cat, dog or any other domesticated animal should immediately contact their family veterinarian to safely examine your pet and test for bird flu if needed.

Additional guidance is available on the New Jersey H5N1 page at https://www.nj.gov/.../divi.../ah/livestockhealth/h5n1.shtml .

On Tuesday, the Borough of Pitman announced the closure of two parks on their Facebook page due to excessive bird deaths.

 This was followed up by a more detailed announcement:

It was just about a year ago, we were following the outbreak of H5N1 among colony of domestic cats on a property in western New Jersey (see Hunterdon County DOH Reports 4 More Cats Test Positive for HPAI H5N1 (Ttl=6)).

While we await test results, for now the NJ Fish and Wildlife Department is offering the following :

What Do You Do if You See a Group of Sick or Dead Wild Birds?

Please fill out the Wild Bird Disease Reporting Form .

How Do I Report Sick or Dead Domestic Birds?

If you are reporting sick or dead domestic poultry, please call the New Jersey Department of Agriculture Division of Animal Health at (609) 671-6400.

What if I Have Questions About Human or Domestic Pet Health Due to H5N1?

If you have questions about human or domestic pet health due to H5N1, please direct your questions to your local health department .

What are Disposal Options for Property Owners?

While NJ DEP Fish & Wildlife does not advise that the public handle sick or dead wildlife, if you have a dead bird on your property and are electing to dispose of the carcass, precautions should be taken:

• PPE should be worn, including gloves, a mask, and eye protection.
• Avoid direct contact between you and the animal by using a shovel to move the carcass.
• Double-bag each bird, close the bag using a zip-tie, and place in an outdoor trash bin inaccessible to pets and other wildlife.
• Following disposal, immediately wash your hands with soap and water and disinfect any non-disposable items using a diluted household bleach solution. Allow the disinfectant to sit on the item for 10 minutes before rinsing with warm water.

Residents can also contact their local municipality or county to inquire about animal control services or private wildlife control services able to dispose of dead wildlife.

Sage advice, assuming anyone is listening.