Species

Invertebrates

Learn more about the invertebrates monitored by the LiMPETS program. The list below includes:

  • 17 core taxa that are monitored at as many sites as possible
  • 5 other taxa (denoted with *) that are monitored at only one or two sites

Go to Datasheets and Forms to find out which species are monitored at your LiMPETS site of interest.

Owl Limpet(Lottia gigantea)
Owl Limpet
Description:
This is the largest limpet in North America, reaching sizes up to 8 cm (3.5 inches) in length. The shell is oval and low in profile with the apex (highest point of the shell) positioned far forward. Shell surface often rough with raised brown areas relative to white areas. Tentacles and side of foot gray.
Distribution:
Neah Bay, Washington to Baja California.
Habitat:
Found in the mid to high zone, on cliff faces and rocks of wave-exposed shores.
Diet:
Grazes algal films off rocks with a hard radula.
Fun Fact:
Owl limpets are hermaphrodites. They are born males and become females as they grow older and larger. The females have distinct grazing territories or “farms” that they clear by scraping rocks free of algae. This action creates space and promotes algal growth. Females are territorial and will dislodge small mussels, limpets and anemones from their territories by bulldozing them off the rock with the edge of their shell.
Reason for Monitoring:
Humans eat owl limpets and preferentially take the largest limpets in a population for consumption. As a result, populations may become dominated by smaller males, skewing the gender ratio and decreasing reproduction.
References:
Morris, R.H., D.P. Abbott, and E.C. Haderlie. 1980. Intertidal Invertebrates of California. Stanford University Press, Stanford, California.
MaRINE: Multi-agency Rocky Intertidal Network