NEW YORK (AP) — New York City's Department of Parks and Recreation is starting an aerial survey of the deer population of the Bronx.

City officials say the weeklong survey will start Saturday. It will take place between the hours of 6 p.m. and 1 a.m., weather permitting.

The survey will include Pelham Bay and Van Cortlandt parks as well as the Riverdale section.

A single-engine plane will use an infrared camera to measure the temperature difference between the deer and the surrounding environment.

It will fly at altitude of about 1,000 feet.