Friday, December 17, 2010

Northern Harrier

Last Saturday was the Natural History and Identification of Raptors Workshop held at Prairie State Park.  Jeff Cantrell gave an entertaining and educational seminar on various types of birds of prey seen in Missouri complete with some mounted examples.

The second half of the program was a field trip around the prairie.  It turns out that raptors are more intelligent than the attendees.  While we walked around in 34 degree weather with 25 mph winds, they pretty much stayed hunkered down some where out of the wind.

Northern Harrier- Joe Motto*
The star of the show was definitely the collection of Northern Harriers that they must keep for special occasions like this.  Said to be "uncommon migrants in Missouri", there were several gliding over the fields.  Well, not exactly gliding.  With the wind, they were hard pressed to maintain a flight path for more than a few seconds before being blown off course.  Their normal distinctive flight pattern follows the contour of the land, maybe 8 to 10 feet above the ground, attempting to startle prey into exposing themselves.  What they lacked in elegance of flight Saturday they made up with persistence.

Their breeding grounds are in Alaska, Northern Canada and down to the Baja Peninsula, especially in coastal areas, while their wintering area extends as far as South America.  Their normal prey is rodents, snakes, birds and insects.

A few interesting facts:
  • Unlike other raptors, they depend on their acute hearing as well as sight to locate their prey.  They are said to be able to hear insects as they glide along close to the ground.  They have an owl-like "facial disks" which helps them gather and locate sounds
  • Males may mate with up to 5 females in a breeding season.  They hunt and bring back prey while their mate(s) care for the young.
  • They are attracted to smoke from far away, coming in to hunt in front of the flames to catch animals running from the fire.
Pictures and a recording of their call is found at allaboutbirds.org.
*  More of Dr. Motto's wildlife photographs are at this site.