Shoreline Habitat Classification

Marine, intertidal, boulder, partially exposed, eulittoral

Sites not directly exposed to oceanic swell but with substantial wave action are found throughout the Strait of Juan de Fuca, and on the west and south sides of the San Juan Islands and Whidbey Island. Wave energies are less but there is a consequent increase in desiccation stress (and perhaps other stresses) leading to somewhat lower diversities than at the most exposed sites. In Washington, low tides on the more inland waters also fall at highly stressful hours (nearer midday in the summer and midnight in the winter), contributing to lower diversities. Communities on tops and sides of boulders are similar to those on bedrock, but the spaces on the lower edges and beneath boulders provide additional spatial complexity; these microhabitats tend to be shadier (and thus cooler) and less exposed to wave disturbance. Boulder habitats thus often have very high species diversity.

Class ID
6
Class name
Marine, intertidal, boulder, partially exposed, eulittoral
Length
3.00
Primary substrate
Bedrock
Secondary substrate
Boulder
Substrate stability
Stable
Substrate key details
No sediment except sand scour at some sites
Wave exposure
Semi-exposed
Blue book classes
Marine intertidal rock: Partially exposed
Map/survey site examples
Tongue Point; West side San Juan and Lopez Islands
Fish sampling sites
Tidepool/Boulder: Twin Rivers
Diagnostic species
Mytilus californianus
Saccharina sessile
Phyllospadix
Katharina tunicata
Pisaster ochraceus
Anthopleura elegantissima
Balanidae
Lottia
Oligocottus maculosus
Anoplarchus purpurescens
Gobiesox maeandricus
VEC common associates
Haematopus
Habitat classification system
Related images
Overview of class 6
Example of class 6 at Snow Creek, east of Neah Bay
Example of class 6 at Cattle Point, San Juan Island