Estuarine, intertidal, gravel, partly enclosed, eulittoral

Some partly enclosed estuarine intertidal sites in the Salish Sea have a poorly sorted substratum of mixed cobble, gravel, and sand, often distributed in patches along the beach. The relative proportions of sand and gravel vary with elevation, space, and time. These habitats are less diverse than mixed-coarse beaches because they tend to lack the stable surface cobble. Eelgrass beds often lie just subtidally of these beaches where the substratum becomes less coarse. These beaches are used as feeding areas by cutthroat trout, juvenile salmon (chum and pink), fish-eating birds such as cormorants, grebes, loons, mergansers, and great blue herons, and bivalve-eating birds such as scoters and goldeneyes.

Habitat attributes

Class ID: 
70
Class name: 
Estuarine, intertidal, gravel, partly enclosed, eulittoral
Length: 
30.0 km (in WA)
Primary substrate: 
Gravel
Secondary substrate: 
Sand
Tertiary substrate: 
Substrate stability: 
Mobile
Substrate key details: 
Few stable surface features
Wave exposure: 
Semi-exposed, Semi-protected
Blue book classes: 
Estuarine intertidal gravel: Open; also some features of mixed-coarse and sand
Map/survey site examples: 
Northern Indian Island, areas south of Port Townsend, inner Kilisut Harbor
Fish sampling sites: 
Diagnostic species: 
  • Exosphaeroma
  • Hemipodia simplex
  • Armandia brevis
  • Zostera marina
  • Salicornia depressa
  • Platichthys stellatus
  • Cymatogaster aggregata
  • Syngnathus leptorhynchus
Species notes: