05/14/2025
Update on Lake Huron Fish Die-Off: 14 May.
I have heard from the MNR (see below for full email) and they have confirmed that some fish samples were collected from Kincardine, Goderich, and Lambton Shores and submitted for analysis yesterday. Part of the analysis will be screening for viral hemorrhagic septicemia (VHS). Results from testing of those samples can take between 5-6 weeks so we won't know for a while if VHS is involved in the ongoing die-off in Lake Huron.
While we wait for results, I encourage everyone to treat this as a potential outbreak of VHS until we know otherwise. If VHS turns out to not be involved, preventative measures won't hurt, but if VHS is involved and we do nothing until we are sure, a lot of damage could be done to vulnerable fish populations like those in the Old Ausable Channel.
One of those preventative measures is to clean up the potentially diseased carcasses from the beaches. MNR have indicated that clean up on public beaches is the responsibility of the municipality while clean up on private beaches is the responsibility of the landowner. So if you live near a public beach, please contact your municipality to ask them to clean up the carcasses. I will be making a separate post on what I've found out able safe disposal practices.
Ways to control the spread:
1. Ask your municipality to clean up dead fishes from public beaches.
2. Do not move fishes, including baitfish, between waterbodies.
3. Don't move boats or other aquatic equipment between waterbodies.
4. If you must move equipment from one waterbody to another:
a. Drain all water from the boat and bilges, prior to leaving the shore of the waterbody.
b. Clean boats and equipment (particularly boots) of all mud, plants, and other debris as these can hold the virus.
c. Disinfect all surfaces and gear that has come into contact with lake water or fish with a 10% bleach solution (100 mL bleach per 900 mL of water). Soak items for 10 minutes where possible.
d. Let all boats and equipment fully dry in the sun prior to use in a different waterbody.
5. Continue to report newly dead fishes to the MNR fish die-off line (1-800-387-7011), particularly those that show signs of possible VHS (red blotches on skin, around eyes, mouth, and bases of fins).
6. Spread the word! The more people who are aware, the better.
May 13, 2025. Email from Upper Great Lakes Management Unit:
Our team, situated in Owen Sound, is responsible for the reporting and investigation of Fish Die-off events within the Canadian waters of Lake Huron and Georgian Bay (Zone 13 and 14). We work alongside the Canadian Wildlife Health Cooperative (CWHC) to monitor large wild fish die-offs related to disease, particularly emerging diseases.
We have received reports of dead fish over the last week and we have pursued sample collections today and yesterday. Given the public interest in this matter and the challenges with collecting moribund or fresh specimens, we also encourage concerned public members to notify the fish die-off hotline at 1-800-387-7011 as soon as possible after a new mortality event occurs. However, it is important note that testing may not provide all the answers. In some cases, the cause of death may never be clearly identified by a laboratory. Especially following atypical seasons, such as this past winter, wherein a multitude of factors may be at play.
A recent update we can provide is that [we were] successfully able to collect samples at 2 locations. 5 moribund and 1 dead Gizzard shad were collected in Kincardine and Goderich, respectively, and have been successfully received by the CWHC laboratory for testing. In general, the lab asks for an allowance of 5-6 weeks for virology results. They were made aware to specifically test for viral hemorrhagic septicemia (VHS). Additionally, we are aware of several more samples of alewife and largemouth bass incoming to the CWHC which were provided by Pinery Provincial Park staff.
As you are likely aware, Lake Huron and Georgian Bay are considered positive waterbodies for VHS in Ontario, with the Great Lakes strain known to affect both game fish and baitfish species. Although VHS has not been confirmed in this particular die-off event, it is important to note that it does not pose a risk to human health. The virus does not affect humans and fish carrying VHS are safe to eat and handle. However, people should not consume or handle fish that look sick, are dying, or are already dead and found washed up along the shoreline. Members of the public should always make sure that any fish they are going to consume should be cooked thoroughly. As with any dead or dying fish or wildlife, pets should not be allowed to eat or come into contact with dead or dying fish.
With respect to VHS, our management efforts to slow the spread of VHS include education and awareness efforts for members of the general public and restrictions on the movement of baitfish as a potential vector for this virus. More information on Ontario’s approach to VHS can be found at https://www.ontario.ca/page/viral-hemorrhagic-septicemia-vhs.
In terms of cleanup, Municipalities are responsible for removing fish from public beaches that they own, while MECP is responsible for removing fish from swimming beaches in Provincial Parks. Individual landowners are responsible for the cleanup of fish from their shorelines. Attempts to sample fish by Ministry staff are often unsuccessful due to the state of the carcasses found after reports are made.
However, we are willing and able to sample appropriately fresh fish given notice.
If possible, we would like to encourage future public inquires or reports be made to the MNR reporting website (https://www.ontario.ca/.../dead-animals-or-fish-found...) or the MNR fish Die-off hotline. Our team is committed to addressing the concerns brought forth and will share any results with the public as soon as possible. Please feel free to share the informational links we provided below and contact us if you have any additional questions.
Dead animals or fish found on your property: https://www.ontario.ca/.../dead-animals-or-fish-found...
Viral hemorrhagic septicemia (VHS) https://www.ontario.ca/page/viral-hemorrhagic-septicemia-vhs
Sustainable bait management: https://www.ontario.ca/.../sustainable-bait-management...