Nestling diets of coexisting salt marsh sparrows: Opportunism in a food-rich environment

  title={Nestling diets of coexisting salt marsh sparrows: Opportunism in a food-rich environment},
  author={William C. Post and Jon S. Greenlaw},
  journal={Estuaries and Coasts},
The saltmarsh sharp-tailed sparrow (Ammodramus caudacutus) and the morphologically similar seaside sparrow (Ammodramus maritimus) occur together in Atlantic coast salt marshes. Over 2 yr we examined food exploitation patterns to gain an understanding of how these species coexist and to characterize the trophic conditions that allow the maintenance of different mating systems within the same habitat. In the promiscuous saltmarsh sharp-tailed sparrow, only females feed the young, while the young… 
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