Marine, intertidal, cobble, partially exposed, eulittoral

Cobbles in partially wave-exposed areas are unstable, suffering frequent overturning by waves, and also are hybrid environments because cobbles are virtually always mixed with, or overlie, other substrata. Beaches visually dominated by cobbles, rather than being a clear mix of substrate types, are put into this category, but often have at least some underlying sand. Cobble habitats in moderately to highly wave-exposed areas are generally species-poor because of this high disturbance. The organisms characteristic of this habitat are those that can hide just under the cobbles and move quickly or resist being crushed when cobbles are rolling, such as shore crabs, amphipods, and isopods. Beaches with sand beneath the cobbles contain some infauna that can bury more deeply during storms, such as certain clams.

Habitat attributes

Class ID: 
14
Class name: 
Marine, intertidal, cobble, partially exposed, eulittoral
Length: 
8.0 km (in WA)
Primary substrate: 
Cobble
Secondary substrate: 
Sand
Tertiary substrate: 
Substrate stability: 
Mobile
Substrate key details: 
Sand under (unstable) cobbles at some sites
Wave exposure: 
Semi-exposed
Blue book classes: 
Marine intertidal cobble: Partially exposed
Map/survey site examples: 
Partridge Point, Slip Point, North Beach, Morse Creek
Fish sampling sites: 
Diagnostic species: 
  • Hemigrapsus nudus
  • Macoma inquinata
  • Littorina
  • Lottia
  • Anoplarchus purpurescens
  • Gobiesox maeandricus
  • Oligocottus maculosus
  • Xiphister atropurpureus
VEC common associates: 
Leukoma staminea
Species notes: