How to Distinguish from Similar Species: Other Nucella have no frilly lamellae and rarely exceed 3 cm in length. Nucella ostrina has alternating large and small spiral ridges. N. canaliculata has many spiral ridges of similar size. Geographical Range: Nucella lamellosa is found from the Bering Strait to central California. Depth Range: Low intertidal to mid intertidal Habitat: Rocky substrate, commonly found on mussel beds Biology/Natural History: A most peculiar species because of its ability to vary so much in shape, color, and texture from one individuals to the next. This makes it very hard to key out. It is one of the most common intertidal whelks in the Pacific Northwest. Nucella lamellosa is a carnivore, feeding on acorn barnacles (photo) and mussels. After locating its prey the whelk uses its radula to scrape through the shell and eat out the soft flesh inside. Predators include the red cancer crab Cancer productus and the seastar Pisaster ochraceus. Prolonged exposure to chemical cues from C. productus, which cracks the snail's shell during predation, induced growth of a more rotund shell with thicker walls. Prolonged exposure to chemical cues from P. ochraceus, which reaches into the shell, induced growth of elongated shells with higher spires which allowed the snail to further retreat into the shell. These cues also stimulated the snails to seek shelter more consistently (Bordeau, 2009) This snail may be found congregating in large groups to breed in the spring and summer (photo). Their eggs are in oatlike capsules which are attached by stalks to the rocks (photo) In the study by Sorte and Hofmann (2005), thermotolerance of different Nucella species along the coast was found to be correlated with the latitude range and tidal height each species occupies. N. ostrina, which occurs higher in the intertidal than does N. canaliculata in Oregon and does not extend as far north, had higher heat tolerance than did N. canaliculata. N. emarginata, which extends the farthest south, and N. ostrina, which lives higher in the intertidal, recovered more quickly from thermal exposure than did N. canaliculata and N. lamellosa, which live lower in the intertidal, and N. lima, which has a more northern range. These differences in heat tolerance may be related to HSP70 molecular chaperones. The famous purple dye from the city of Tyre, that colored
royal Roman
robes, was made from a relative of Nucella.
The snails were
ground up in a stone mortar; different combinations made different
shades
of purple. The dye should be fixed with lemon juice as a
mordant.
The American species produce a much less brilliant purple than do the
Mediterranean
species.
References: Dichotomous Keys:
General References:
Scientific Articles:
Bordeau, Paul E., 2009. Prioritized phenotypic responses to combined predators in a marine snail. Ecology 90:6 pp 1659-1669 Rawlings, 1999. Adaptations to physical stresses in the intertidal zone: the egg capsules of neogastropod molluscs. American Zoologist 39:2 pp. 230-243 Sorte,
Cascade J.B. and Gretchen E. Hofmann, 2005.
Thermotolerance and
heat-shock protein expression in northeastern Pacific Nucella
species
with different biogeographical ranges. Marine Biology 146:
985-993
General Notes and Observations: Locations, abundances, unusual behaviors, etc.: Young individuals of
this species are frequently
a bright orange and may have no lamellae. See the photos
below for
one with tiny lamellae--Dave Cowles
This aggregation of egglaying Nucella lamellosa was under a boulder on Sares Head, April 2011. Photo by David Cowles In July 2005, Jon Mayberry, Matt Henderson, and Taylor Wilkins did a student project titled "Tidal effect on daily migration patterns in Nucella lamellosa". In the study they followed vertical movements of N. lamellosa through six height zones in an aquarium during changes in water depth that simulated the ambient tidal cycle, and in a control tank that always remained full. They found that the snails in the control (full) tank continued to move all the time while snails in the tidal tank stopped moving almost entirely during low tide except for a few that fell to the bottom of the tank, making a highly significant difference in movement between the tidal and nontidal tanks at low tide. The average height of the snails differed both at high and at low tide, with snails in the tidal tank higher. This may have been due to the fact that at low tide the snails in the tidal tank "froze" in position. They also observed what might have been a migration downward at nightfall in both tanks. The figure below (figure 3 from their data) summarizes their results. Zone 0 was at the bottom of the tank, zone 6 on top.
Authors and Editors of Page: Nathaniel Charbonneau (2002): Created original page Edited by: Dave Cowles 8-2002, 12-2004 Edited by Hans Helmstetler 1-2003 |