Are American bullfrogs ecological time bombs?
Millions of bullfrogs imported into California carry an infectious fungus that, although not fatal to bullfrogs, can wipe out populations of native frogs.
Batrachochytrium dendrobatidis breeds in the conditions in which bullfrogs, many of which are imported from Taiwan, are shipped in.
The main purpose for shipping the live bullfrogs is for use in traditional Asian cuisine.
Bullfrogs carry the fungus but do not die from it. Most of the millions of bullfrogs imported to California each year for use in the food, pet and dissection trades are infected with the fungus, according to several recent studies.
Though the California Fish and Game Commission voted to ban bullfrog imports, it decided not to enforce the ban.
Why not? To avoid a culture clash, apparently. Or at least they caved to the pressure of Asian American groups, who see the amphibians as an important part of their food culture. The ban also targeted bullfrog food imports, but not pet stores, which was seen as unfair towards California’s Asian American community
Another strange twist is that the bullfrogs are originally American (albeit from the Northeast), but were imported to Asia and then farmed in China, Taiwan and Brazil for food. They were also introduced into the California ecosystem during the gold rush after miners hunted native frogs almost to extinction.
Read more about California’s bother with bullfrogs in the Los Angeles Times.
American bullfrogs are not just a worry due to the fungus they carry. The ultra-adaptable species is spreading out in parts of South America due to changing temperatures attributed to climate change.
From the New York Times:
Unless steps are taken to prevent the invasion, the authors write, climate change could enable the American bullfrog to thrive in areas of the Andean-Patagonian forest, eastern Paraguay and northwestern Bolivia, where the species has not yet been reported.
That means that not only will a fungus carrier arrive to spread the disease to other species, a new, adaptable predator will be in the mix, which could spell trouble for native species.