Delesseria decipiens Ecology
decipiens lives in low intertidal to subtidal areas on the west
coast of North America, from Alaska to San Luis Obispo, CA. D.
decipiens is saxicolus,
meaning that it grows on rocks and can be found on the vertical faces
of rocks in the low intertidal areas. D.
decipiens was first collected in 1859 in the Straits de Juan de
Fuca, near present day Washington State. Samples of D. decipiens were
found in the Hopkins Marine Life Refuge growing on buoy lines in late January
and early March. Data collected from the Gilbert M. Smith Herbarium
also indicates that D. decipiens grows in
a wide variety of locations around the Monterey and Carmel Bay areas.
Locations of D. decipiens in the past have included, from north
to south, Point Pinos, Moss Beach, Asilomar, Spanish Bay, Point Joe,
Cypress Point, Pescadero Point, Pebble Beach, Stillwater Cove, Carmel
Beach, Mission Point and Soberanes Point. Herbarium notes suggest that D.
decipiens can grow in a tidal range form 0.5 to -1.5 feet, although
some sources indicate that it grows at depths of 20 feet. Map
of coastline of the Monterey Peninsula.
To see additional data from the G.M. Smith Herbarium Click Here
Seasonal Growth Delesseria
decipiens is a spring annual that can be found in the Monterey
Bay region from late January to July. Based on a survey of D. decipiens samples
in the Gilbert M. Smith Herbarium, plants seem to reach their maximum
size, as measured by the length of their primary midrib, in May and
June. There did not appear to be any pattern of reproductive development
with samples becoming reproductively identifiable in April and continuing
Sensing UV Light Studies done in Delesseria sanguinea have shown that D. sanguinea is a sensitive and reliable indicator of UVB light, demonstrating a significant reduction in growth rates when compared to exposure to visible sunlight and UVA light alone. This is significant as continued thinning of the ozone layer allows more UVB light to reach the earths surface. UVB is a highly destructive form of UV light and accurate indicators such as D. sanguinea could be highly valuable in monitoring the effects of UVB levels on biological life. It is not currently know whether D. decipiens shares the same UVB sensitive properties, but testing this property could be an area of further research.
Delesseria decipiens as a habitat Delesseria decipiens can act as a habitat for other invertebrates and marine organisms. In a sample collected on March 4, 2004 from a buoy line several invertebrates were found in association with D. decipiens. These invertebrates included several caprellids, called skeleton shrimp (Phylum Arthropoda, Class Crustacea, Order Amphipoda), a tiny nudibranch (above right) Coryphella trilineata (Phylum Mollusca, Class Gastropoda, Order Nudibranch), several acorn barnacles of the genus Lepas (Phylum Arthropoda, Class Crustacea. Order Thoracica), and an unidentified worm from the phylum Nemertea about 2mm long.
Gooseneck barnacle living on Delesseria decipiens (right)
Caprellid shrimp attached to algae