This marks the fourth year of the Belfast bird bus, a collaborative recreational opportunity sponsored by the Waldo County YMCA, the Belfast Bay Watershed Coalition, and the city of Belfast.

The bus will go to Acadia National Park Saturday, March 6. The daylong trip will focus on waterfowl and other birds on their spring migration. Additionally, tour leader Seth Benz, who was an interpretive ranger at Acadia National Park, will discuss how the geology of the park helps shape bird migration.

The tour departs from the Waldo County YMCA at 8 a.m., and returns by 3:30 p.m. Participants are urged to bring binoculars, a bag lunch and dress for the weather. The bird bus will visit a series of exceptional “hot spots” to take advantage of Acadia’s majestic scenery and maximize bird spotting.

Benz will share tips for identifying waterfowl as well as their annual life cycles. Participants can expect to see a variety of waterfowl, including diving or sea ducks, loons and grebes. This is also a time when early-returning birds of prey may be seen.

These families of birds represent some of the more than 250 species that have been identified in the park. Benz noted that late winter specialties such as white-winged and red crossbills are among the perching-bird possibilities and add anticipation of the unknown at every stop.

The bus tour is designed for people of all ages and all levels of bird-watching interest. The tour is not physically challenging, as the stops provide exceptional viewing opportunities in close proximity to the bus. Benz, the tour leader and bus driver, has more than two decades of experience working for both Maine and National Audubon.

To register, call the Y at 338-4598. The cost is $30 per person. Deadline for registration is Friday, Feb. 26.