In 1992, the Montrose trustee agencies funded a study of eggshell thinning and DDT contamination levels in seabirds of the Channel Islands. These studies demonstrated that many seabirds had eggshell thinning of greater than 15 percent compared to pre-DDT era eggs. Eggshell thinning greater than 15 percent can lead to failed hatching of eggs.
As a result of these studies, the Montrose Settlements Restoration Program (MSRP) prioritized a number of seabirds for restoration efforts based on evidence of eggshell thinning. These seabirds are the Cassin’s Auklet, Western Gull, California Brown Pelican, Double-crested Cormorant, Brandt’s Cormorant, Pelagic Cormorant, Ashy Storm-Petrel, and Pigeon Guillemot. The Scripps’s Murrelet is also a priority species for restoration based on its conservation status.
Historical records show that higher number of seabirds was present on the Channel Islands and their offshore rocks. Seabirds were impacted by human activities on these islands, including the introduction of feral cats, grazing, introduction of non-native plants, and changes to the habitat. The goals of the seabird habitat restoration projects are to restore seabird nesting habitat, attract seabirds to the restored sites, and to remove non-native plants and animals.
Visit the pages below to find out more information about our seabird restoration projects on the Channel and Baja California Pacific Islands.
Channel Islands Seabird Protection Network