A wildlife expert says last year's improvements at Sitka's airport are helping to reduce the risk of collisions between birds and planes.

The Daily Sitka Sentinel reports that David Tresham told the Sitka Chamber of Commerce Wednesday that grass sections of an infield near the runway were filled with gravel, and that has made a difference. Before, the area would fill with water, attracting birds.

Tresham is a wildlife specialist with the U.S. Department of Agriculture who is managing wildlife threats to planes that use Sitka's airport.

Bird strikes are a big concern there. An Alaska Airlines jet hit an eagle on takeoff in 2010 and had to abort the flight.

Tresham says birds remain a concern, but workers have done a good job identifying potential problems.