State conservation officials are asking for the public’s help tracking loon deaths this summer after receiving a “small but noticeable increase” in calls from people finding dead loons.

Reports and test results point to West Nile virus, which was confirmed as the cause of death in two of three loons from northeastern Minnesota earlier this month, the Department of Natural Resources said Thursday.

While individual bird deaths are normal and “not cause for alarm,” the agency said it’s asking lake homeowners and other lake users to contact a regional nongame wildlife office if they see two or more dead loons on a single lake with no obvious injury or cause of death.

Aug. 2012 West Nile virus cases on the rise in Minnesota

West Nile was first confirmed in Minnesota in 2002 and was fingered as a cause of loon deaths in 2005.

The virus is spread through mosquito bites, and most people and animals fight off the virus and develop antibodies against future infection. Loons and crows, however, are especially susceptible to the infection, the DNR said.

“Minnesotans love our loons and it’s concerning for people to find them dead. When we start seeing multiple birds dying on a single lake, we want to know about it so we can start tracking the information and determine when further testing is warranted,” DNR nongame wildlife specialist Gaea Crozier said in a statement.

“While there isn’t a way to treat the West Nile virus infection,” Crozier added, “knowing the cause can help us rule out other, preventable causes of mortality.”