Science foundation Chapter 5 Appendix 5.1: Case study Forester's tern (Sterna forsteri) and California least tern (Sternula antillarum browni)

This case study considers two tern species that breed within the San Francisco Bay Estuary, Forster’s Terns (Sterna forsteri) and California Least Terns (Sternula antillarum browni). Forster’s Terns are medium-sized (140 g) terns that breed in coastal and interior marshes of North America. Forster’s Terns can exploit ephemeral habitats, and colony locations often move among years with change in habitat suitability and resource availability. Least Terns are smaller-sized (45 g) terns that breed along beaches and major interior rivers of North America, and winter along marine coastlines in Central and South America. Forster’s Terns and California Least Terns breeding in San Francisco Bay tend to use the same nesting colony locations each years.