The welcome birds of spring will soon return to fields and farms, feeders and fences. Heralding yet another sign of the coming season: the Cornell Lab of Ornithology's popular Spring Field Ornithology course. For the novice and expert alike, this eight-week course will clear the cobwebs of winter and hone knowledge of bird behavior and identification skills. The course, now in its 29th season, runs from March 29 to May 21.

The course is offered in two sections: Wednesday night lectures and guided weekend field trips. The lectures are held at the Lab of Ornithology on Sapsucker Woods Road and led by Stephen Kress, the National Audubon Society's vice president for bird conservation. Lecturers, including Cornell scientists Ken Rosenberg, Kimberly Bostwick and David Winkler, will address a variety of topics, including eggs and nests, why birds sing, courtship rituals and conservation.

The field trips take place Saturday and Sunday mornings to give participants an opportunity to practice skills learned during the week at such birding hot spots as Stewart Park, Dryden Lake and Derby Hill, and a longer trip to the bird-rich Montezuma National Wildlife Refuge at the north end of Cayuga Lake. An additional trip to Cornell's Arnot Forest in Van Etten will include special sessions about bird photography and sound recording, and an overnight jaunt to the coast of New Jersey in May will include stops in Cape May and Stone Harbor.

The cost is $150 for lectures, $150 for the field trips or $290 for both, with an additional fee for the overnight New Jersey trip; Lab of Ornithology members' fees are discounted. Participants enrolled in both the lectures and field trips will receive a free copy of the book "The Birds of Sapsucker Woods," which contains descriptions of and colorful artwork on most of the common local birds.

Space is limited; call (607) 254-2452 (outside Ithaca, 800-843-2473) to sign up. For more about the course schedule or to register online, visit http://www.birds.cornell.edu/sfo. E-mail questions to sfoclass@cornell.edu.