Bullfrogs

Asked May 1, 2015, 2:44 PM EDT

I have a lot of bullfrogs in the water behind my house. Are they native? How can I get rid of them?

Washington County Oregon invasive species frogs herpetology bullfrog rana catesbeiana lithobates catesbeianus

1 Response

The American bullfrog (Lithobates catesbeianus formerly Rana catesbeiana) is native to the eastern part of the United States; however, it was introduced to, and considered invasive in, the western part of the US. This species was introduced into Oregon in the early 1900s as a food item (frog legs).

Bullfrogs out-compete native species of frogs in food, habitat, and reproductive capacity. They also transmit diseases to native species. Bullfrogs are voracious feeders, eating just about anything they can catch and put in their mouth. This includes insects, amphibians (including other frogs, both native and other bullfrogs), fish, reptiles (turtles and snakes), small mammals, and birds. They also reproduce in larger numbers than the native frog species. Bullfrog females lay up to 20,000 eggs at a time, while native species such as the red-legged frog lay up to 5,000 eggs. Based on a fact sheet published by the Oregon Department of Fish and Wildlife (ODFW), bullfrogs are a controlled species and can be legally harvested any time of the year, and no angling license is required. ODFW recommends removing bullfrogs you find in the wild. However, make sure you're dealing with a bullfrog. Most native species of frogs in Oregon are protected and cannot be removed from the wild or killed. Here's a link to the ODFW fact sheet on bullfrogs:
http://www.dfw.state.or.us/conservationstrategy/invasive_species/docs/bullfrog_fact_sheet.pdf

To make sure you have the most current information, however, I recommend you contact the ODFW at (503) 947-6000.
Hope this answers your question and thank you for using Ask an Expert.

Jim