Crows are highly susceptible to the West Nile virus, an illness spread by infected mosquitoes.

Because of their susceptibility, crows can be a barometer for humans. A dead crow can indicate the presence of illnesses in the area, California Lutheran University professor Reese Halter said.

Anyone who sees a dead crow can report it on a hotline set up by the California Department of Public Health at (877) 968-2473.

If the person calling the hotline provides information that leads to the determination that the dead crow needs to be examined, the caller will be instructed to wear gloves or use a shovel to put the crow inside a double plastic bag. The dead bird is to be stored away from sunlight, and someone will be sent to pick up the bird and ship it to a laboratory for West Nile virus testing.

For testing, the crow must have been dead for less than 24 hours, said Randy Smith, an environmental health specialist with the Ventura County Environmental Health Division.

Other types of animals, such as pigeons, quails, doves, domesticated chickens and squirrels, can be picked up for examination for various diseases Mondays through Fridays by calling the hotline. Animals run over by vehicles aren’t accepted.

Another way to attack the spread of the virus is to prevent mosquitoes. To report vacant pools or standing water, which are breeding grounds for mosquitoes, call (805) 658-4310.

Those with fish ponds at their homes can call (805) 662-6582 to have free mosquito-larvae-eating fish delivered.

As the weather heats up, the West Nile virus is more easily transmitted, Smith said.

According to the Center for Disease Control, the West Nile virus is serious for one in 150 people, with symptoms that include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis. Symptoms may last several weeks, and neurological effects may be permanent. About 20 percent of those infected have mild symptoms and 80 percent have none at all.

So far this year, there’s no evidence of the virus in the area, Smith said.