NESTING HABITAT OF BELDING SAVANNA SPARROWS IN COASTAL SALT MARSHES

Although the Belding's Savannah sparrow (Passerculus sandwichensis bel dingi) is listed as endangered in California, little is known about th e factors that affect its abundance and distribution. Numbers of breed ing pairs, nesting territory sizes, and vegetation characteristics wer e measured at fourteen study plots in two southern California coastal wetlands, Tijuana Estuary and Los Penasquitos Lagoon. Sparrows nested in middle salt marsh habitat in areas of dense pickleweed (Salicornia virginica) or saltgrass (Distichlis spicata). No nesting territories w ere found in transitional upland or low marsh habitat. Territory sizes were highly variable and significantly larger at Tijuana Estuary. Ter ritory size may be related to nest site availability and water levels at time of establishment. More research is needed on the effects of ha bitat quality on reproductive success and territory size.