Snake fungal disease

Close up photo of a garter snake in the grass
Photo by Jon McGinnis
Garter snake in the grass.

Snake Fungal Disease (SFD) is a disease in snakes caused by the fungus Ophidiomyces ophiodiicola.

This fungus was first isolated from captive snakes in Europe and the United States in the mid-1980s, and now experts consider it to be an emergent pathogen across North America. It was recently found in the western United States, in Idaho and California. The incidents of SFD have steadily increased over the last few years, putting many snake species at risk.

Snakes perform important ecosystem services such as controlling populations of small mammals and enhancing biodiversity. Ophidiomyces ophiodiicola is not known to cause infections in humans or other mammals.

Report snake observations

Public reports of sick, injured, or dead snakes provide valuable information to track snake populations in Washington. Report your observations here

What to do if you find a sick snake

Live snake

  1. If you find a live, non-venomous snake with possible signs of snake fungal disease (SFD), please capture the snake and place in a snake bag, pillowcase, or box with appropriate air holes/ventilation. If using a pillowcase or bag, be sure to tightly secure the top (double knots) to prevent snake from escaping.
  2. Be sure to wear gloves when handling the snake. Dispose of gloves in a trash can.
  3. Keep the snake in a well-ventilated area that is the same temperature as where the snake was found.
  4. Be careful to not leave the snake in direct sunlight as this could cause overheating/undue suffering. Err on the side of keeping the snake cool.
  5. Contact Katie Haman for further instructions.

Dead snake

  1. Using gloves, collect the carcass into a sealable bag. Double bag the carcass.
  2. Cool the carcass as quickly as possible. Ideally, place in a refrigerator immediately post-collection. If this is not feasible, place in a cooler with ice packs.
  3. Contact Katie Haman for further instructions.

What are some signs of snake fungal disease?

Some common signs of snake fungal disease include:

  • Localized thickening or crusting of the skin; yellow, crusty scales especially common around the eyes, snout, and chin
  • Ulcerated skin
  • Nodules (abnormal bumps) under the skin
  • Irregular scale surfaces
  • Abnormal shedding
  • Facial disfiguration that can be quite severe, leading to emaciation and death
  • Abnormal behavior (for example, a snake that is active in cold weather)

Can snake fungal disease pass onto my pets or to people?

No, SFD only affects snakes. However, it is always a good idea to handle wildlife with gloves and wash your hands after.

Where has snake fungal disease been found in Washington?

To date, the fungus that causes SFD, O. ophiodiicola has not been found in Washington. However, there have been several reports of a fungal disease in garter snakes that appears to be closely related to O. ophiodiicola-caused snake fungal disease. Because of this, WDFW is closely monitoring the health of Washington snakes to determine if we have a novel snake fungal disease, or if we are in fact witnessing the spread of O. ophiodiicola into Washington.

How the fungus spreads

At this time, it is not well understood how the fungus causing SFD is spread. It is likely that the fungus is shed into the environment by an infected snake, and then spread from the environment to other snakes.

How you can help

You can help us monitor the presence and potential spread of this disease by reporting sick or dead snakes to WDFW. You can also be a friend of snakes by letting them coexist in your yard, and not killing or moving them from your property.

Why snakes matter to our environment

Snakes are key components of healthy Washington ecosystems. Some species of snakes will eat garden pests (slugs) while others eat small mammals. Regardless of their diet, snakes play a vital role in healthy ecosystems and enhancing biodiversity!