Skip to main content
U.S. flag

An official website of the United States government

Endangered fish threatened by Asian fish tapeworm

January 1, 2004

The Asian fish tapeworm, an exotic parasite, has invaded the endangered humpback chub (Gila cypha) population from the Colorado and Little Colorado Rivers in Grand Canyon, Arizona. This parasite causes disease and death in carp in aquaculture settings and may retard growth in hatchery-reared roundtail chub (Gila robusta). Other consequences include destruction and dysfunction of the intestinal lining and adverse changes to certain blood parameters. Introduced into the U.S. in the 1970s with imported grass carp (Ctenopharyngodon idella), the Asian fish tapeworm (Bothriocephalus acheilognathi) was discovered in the Little Colorado River (LCR) by 1990. The LCR is the main tributary to the Colorado River in Grand Canyon and is an important spawning area for humpback chub.

Publication Year 2004
Title Endangered fish threatened by Asian fish tapeworm
DOI 10.3133/fs20053057
Authors Rebecca A. Cole
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Fact Sheet
Series Number 2005-3057
Index ID fs20053057
Record Source USGS Publications Warehouse
USGS Organization National Wildlife Health Center