Spring means osprey nesting and horseshoe crab spawning season is upon us, and Felix Neck Wildlife Sanctuary is looking for volunteers to help keep an eye on the animals.

Felix Neck will host training sessions this month for the osprey monitoring program and horseshoe crab surveys. Osprey spend summers on the Vineyard in their iconic nests, and the osprey population has recovered after a steep decline beginning in the 1970s. An annual census of osprey nests provides valuable data about the fish-eating hawks.

Osprey researcher Rob Bierregaard and lead volunteer Dick Jennings will train volunteers to continue the survey program at Felix Neck on Wednesday, April 12 from 5 to 7 p.m. and Saturday, April 15 from 1 to 3 p.m.

Volunteers are also needed for horseshoe crab spawning surveys. Surveys take place during the new and full moons of April, May, and June, which is when the ancient arthropods traditionally spawn.

Volunteers are expected to attend a training session and complete at least two surveys. Training sessions take place at Felix Neck on Saturday, April 22 from 1 to 3 p.m. and Wednesday, May 17 from 4:30 to 6:30 p.m.

Registration is required for all training sessions at 508-627-4850 or massaudubon.org/felixneck.

Naturalist Susie Bowman will offer lectures about horseshoe crab history on April 18 from 6:30 to 7:30 p.m. at Oak Bluffs Library and May 9 from 7 to 8 p.m. at the Vineyard Haven library.