Waterdogs, they're called, these larvae of tiger salamanders used as live bait for freshwater fishing.
With tiger salamander larvae, anglers hope to catch largemouth bass, channel catfish and other freshwater fishes.
They may be in for more than they bargained for: salamanders in bait shops in Arizona, Colorado and New Mexico are infected with ranaviruses, and those in Arizona, with a chytrid fungus called Batrachochytrium dendrobatidis (Bd).
"These diseases have spread with the global trade in amphibians,'" says James Collins, assistant director for biological sciences at the National Science Foundation (NSF). Collins is currently on leave from Arizona State University. "The commercial amphibian bait trade may be a source of 'pathogen pollution.'" Pathogens are disease-causing agents such as some viruses and bacteria.
Along with biologist Angela Picco of the U.S. Fish and Wildlife Service in Sacramento, Calif., Collins screened tiger salamanders in the western U.S. bait trade for both ranaviruses and Bd, and conducted surveys of anglers to determine how often tiger salamanders are used as bait, and how frequently the salamanders are let go in fishing waters.
The scientists also organized bait-shop surveys to determine whether tiger salamanders are released back into the wild after being housed in shops.
"We found that all tiger salamanders that ended up in the bait trade were originally collected from the wild," says Picco. "In general, they were moved from east to west and north to south--bringing with them multiple ranavirus strains."
Results of the research show that 26 to 73 percent of fishers used tiger salamanders as bait; 26 to 67 percent of anglers released tiger salamanders bought as bait into fishing waters; and four percent of bait shops put salamanders back in the wild after the waterdogs were housed with infected animals.
"The tiger salamander bait trade in the western U.S. i
|Contact: Cheryl Dybas|
National Science Foundation