A cargo ship approaches the coast of Australia. It's been at sea for weeks, and passed through the Panama Canal. The ship picked up a hitchhiker in Panama. A fruit bat.
Bats sometimes roost in ships in port and may be transported to new areas. Silver-haired bats have been found hibernating in ships and yachts in New York. Little Brown Bats roosted aboard a ship that traveled from Canada to Europe, flying ashore after arrival in the Netherlands. The presence of individual Little Brown Bats in rabies-free Iceland has been attributed to travel by ship.
Bats are also translocated when they get closed inside shipping containers. Free-tailed bats from the tropics have been transported in fruit shipments. A Pallid Bat was discovered in Victoria, British Columbia, in a shipment of lettuce from California.
One concern is that these bats could introduce rabies and other diseases to rabies-free areas. Another concern is the transmission of a bat disease that's killed millions of bats in eastern US in the past decade, white-nose syndrome. It's suspected that a bat sick with the disease discovered in 2016 near Seattle, more than a thousand miles from the nearest known infected bats - could have made it to Washington via a cargo ship.
Scientists with the Alaska Department of Fish and Game are collecting reports of bats found aboard vehicles, in shipping containers, or flying out of containers when they are opened or unloaded. This can help better understand, and hopefully combat, the spread of bat diseases to Alaska and other western states.