The Utah Division of Wildlife Resources has another tool to fight small but dangerous creatures.

A new law allows law enforcement-officers to inspect and detain vehicles and boats that may be infested with quagga mussels or zebra mussels. The Legislature approved more than $2 million to implement a program that began in 2007.

"This gives us more teeth to actually encounter boats. That's the big deal, that's given us the bite behind the bark," said Evan Freeman, a state invasive-species biologist.

Officers will be at major water bodies and checkpoints, asking questions and spraying boats with extremely hot water, if necessary.

"The big problem with quaggas are people can ship them and transport them and they are so small you wouldn't know if they were there," said Mike Fowlks, the DWR's chief of law enforcement.

"A year ago, if we saw a boat traveling down the road and we expected it had been to a place infested with mussels, we couldn't stop a boat unless there was actually quagga mussels seen," he said.

Under the new law, officers with reasonable suspicion can stop anyone and have the boat decontaminated. Boats from California, Colorado and Nevada — places that have the mussels — frequently visit Utah.

According to a survey at quagga-infested Lake Mead in Nevada, boaters ranked Utah's Jordanelle Reservoir, Bear Lake and Willard Bay among their top 20 places to visit, Freeman said.

The mussels attach themselves to boat hulls, motors and water-system intakes. They plug pumps, pipes and outboard motors. They have no natural predators and reproduce rapidly, creating layers of shells.

The mussels filter water and consume plankton, which can destroy fish populations. In one of the Great Lakes, Lake Erie, mussels can filter the entire lake in 36 hours, Freeman said.

"They're incredibly dangerous. ... It totally alters the food chain," he said.

The creatures can live up to 18 days out of the water and can be transported alive. A single breeding pair can lead to a huge colony.

The experts said anyone who uses lakes or reservoirs for recreation, irrigation or drinking water should be concerned.

"We're not looking to prosecute people — just decontaminating their boats and getting them on their way," Fowlks said.