Eastward Migration or Marshward Dispersal: Exercising Survey Data to Elicit an Understanding of Seasonal Movement of Delta Smelt

DENNIS D. MURPHY and SCOTT A. HAMILTON

Nearly two decades after the listing of delta smelt on the federal and state endangered species act, comprehensive understanding of seasonal movements of the fish in the San Francisco Estuary is still lacking. The authors used publicly available data from trawl surveys on the distribution of delta smelt to infer seasonal dispersal patterns. The authors concluded that dispersal of delta smelt is more restricted than previously thought. This conclusion has real-world implications for efforts to conserve delta smelt.
The authors’ findings support a conservation strategy that focuses on habitat restoration and management efforts for tidal marsh and other wetlands in north Delta shoreline areas.