LITTLE ROCK (AP) — Bird experts are seeking volunteers in Arkansas and 23 other states to spot the North American Rusty Blackbird, a specie whose population has dropped to a fraction of its size in the 1960s.

Scientists do not know what caused the bird’s decline by about 85-99 percent over the last 40 years, but suspect that loss of habitat is a major culprit, according to the Cornell Lab of Ornithology at Ithaca, N.Y.

There is no monitoring program for the birds, a lab news release says, and the lab, the National Audubon Society and the Smithsonian Migratory Bird Cente...