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.

Common Acorn Barnacles(Balanus glandula/Chthamalus dalli/fissus)
Acorn Barnacles
Description:
Balanus glandula is moderate in size (~2 cm), white with a diamond-shaped operculum and more heavily ribbed walls. Chthamalus dalli/fissus is smaller (<1 cm), brownish with an oval shaped operculum, and smoother walls.
Distribution:
Alaska to Baja California. Balanus glandula has been introduced to the shores of Argentina in the past 30 years, and has become an invasive species there.
Habitat:
Found along the open coast and in bays. Balanus glandula is common in mid to low intertidal on mussels and rocks. Chthamalus dalli/fissus is common in the high to mid intertidal.
Diet:
Plankton. Barnacles filter plankton from the water using their feathery, segmented legs.
Fun Fact:
Barnacles are hermaphrodites. They fertilize one another internally by means of a long penis. The eggs are brooded by the parent and released as nauplius larvae.
Reason for Monitoring:
Competitors for space in the high and mid zone. Major prey for many intertidal species. Susceptible to high mortality from oil spills because oil can stick to high intertidal habitat.
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