Chthamalus dalli in the Intertidal zone at Race Rocks

Physical description:
-Size: Reaches a diameter of only 8 mm (0.3 inches)
Colour: Gray, brown
Shape: It looks like a big brown barnacle but the main the difference is the size – it is much smaller
Texture: They do not have ridges
Geographical range: Alaska to San Diego
Habitat: Intertidal and splash zones but also it can occasionally be seen at lower levels
Feeding: Filter feeders on microplankton
Predators: Predatory snails including Nucella ostrina and sea stars such as Leptasterias. If predators are prevalent, Chthamalus dalli will sometimes grow a slight curve on its shell to protect itself.
Reproduction: They are hermaphroditic and produce sperm and eggs simultaneously. They do not self-fertilize, instead they use their long penis (4.5 cm from the shell) to fertilize another barnacle. Life span: About 3 years
Behaviour: It may spend more than half of its life out of the water because it can live in high intertidal levels
Domain Eukarya
Kingdom Animalia
Phylum Arthropoda
Class Cirripedia
Order Thoracica
Family Chthamalidae
Genus Chthamalus
Species dalli
Common Name: small northern barnacle

References:
http://zipcodezoo.com/Animals/B/Balanus_glandula/
http://beachwatchers.wsu.edu/ezidweb/animals/Chthamalus.htm

Other Members of the Phylum Arthropoda at Race Rocks

Return to the Race Rocks Taxonomy and Image File

The Race Rocks taxonomy is a collaborative venture originally started with the Biology and Environmental Systems students of Lester Pearson College UWC. It now also has contributions added by Faculty, Staff, Volunteers and Observers on the remote control webcams. Alessandra Bustamante Concha-Fernández, Peru ( PC yr 37)