Dulin, G.S. 1990. 1990 summary report of the Forster's and black tern breeding survey of the Minnesota Valley National Wildlife Refuge and vicinity. Report submitted to the Nongame Wildlife Program, Minnesota Department of Natural Resources. 16+ pp.
Forster's terns (Sterna forsteri) and black terns (Chlidonias niger) have both traditionally bred in Minnesota. The breeding range of the Forster's tern is primarily in the Northern Great Plains including the western half of Minnesota extending east through the central part of the state to the Twin Cities. Black terns breed throughout the state except in the northeastern region and in the southeastern region away from the Mississippi River. Casual observations over the last few years have indicated that both species have been breeding on some of the wetland areas included in and adjacent to the Minnesota Valley National Wildlife Refuge. The objectives of the 1990 survey were to identify those wetlands currently being used for breeding by either tern species and to conduct nest counts and fledgling counts to estimate productivity.