The Tern islands were created in the late 1970’s after part of the wetlands were restored to allow seawater influence. During this time, two islands were created to provide nesting habitat for tern species, specifically the California least tern
(Sternula antillarum browni) and habitat for migratory and wintering bird species. The Southern Tern Island (STI) was originally 1.7 acres, and the North Tern Island (NTI) was 1.8 acres in size. Today, STI has 0.6 acres of usable nesting area. North Tern Island has managed to sustain most of the original footprint, the elevation has significantly changed with only part of the island serving as nesting areas for tern and plover species. Over the past 50 years, the islands have degraded in size from weather and erosion. This has resulted in tern nest failure due to flooding during high tides. When considering sea level rise, it is critical these islands are restored to their original size. Currently, four tern species and the Federally listed Western snowy plover (Charadrius nivosus nivosus) nest on the islands. Over the past 50 years, 15 or more bird species have been observed commonly using the islands to rest and
forage during the winter months. Many bird species continue to use the islands as a rest stop while migrating along the Pacific Flyway.
The project will utilize dredging sand to refill and construct the island back to their original size. This will be done during the non-nesting season and accessible through the west levee road which travels from the inlet (dredging area) to the islands. A temporary road will be designed to access the islands. Once the island restoration is complete, the roads will be removed.