KODIAK (AP) — A pest control technician in Kodiak says this year’s warm winter has caused a spike in the number of rats on the island.

BJ Johnson with American Pest Management said rat populations have surged throughout Kodiak Island this year following a third straight winter of warmer-than-normal temperatures.

“It is definitely a rat season,” Johnson told KMXT-FM. “We haven’t had a real cold winter in at least three years now, and hence that gives them plenty of comfortable climate to propagate, and that’s what they’re doing.”

Johnson said the rat being seen around Kodiak is the Norway rat, which Alaska Maritime National Wildlife Refuge biologist Steve Ebbert called the most successful of the invasive rats. The Norway rat in Alaska can be traced back to the first known introduction of rats to the state, Ebbert said, when a derelict Japanese vessel landed on Rat Island sometime before 1780.

“Since that time, there’s been maybe a dozen large islands that have been successfully invaded by rats where the rats have become established,” Ebbert said. “Kodiak got them sometime before 1920.”

Large numbers of rats are a concern because they eat eggs and chicks, which can negatively impact seabird populations.

Johnson said the solution to the island’s rat problem is not a quick fix, but people can help by clearing the base of their homes of excess debris and by not piling wood up against the sides of buildings.