Role of thermal conditions in habitat selection by hydrothermal vent gastropods
Bates, AE and Tunnicliffe, V and Lee, RW, Role of thermal conditions in habitat selection by hydrothermal vent gastropods, Marine Ecology - Progress Series, 305, (2005) pp. 1-15. ISSN 0171-8630 (2005) [Refereed Article]
Habitat selection by 3 Juan de Fuca Ridge
gastropod species relates to their thermal environment.
Both collections and images taken along transects
document the small-scale abundance patterns of
each species with respect to temperature and distance
from vent flows. Lepetodrilus fucensis and Depressigyra
globulus were most abundant at distances from
vent flows of 0 to 25 cm in warm fluids with high temperature
variability (10 ± 5°C) over several time scales.
Both species were also abundant at 26 to 50 cm, where
temperatures were lower with less variability (4 ± 1°C).
Provanna variabilis was most abundant from 51 to
75 cm, where temperatures were stable (3 ± 0.5°C). All
species were absent where maximum fluid temperatures
reached 18°C and their substratum coverage was
related to temperature. When presented with a choice
in vent fluids from 10 to 2°C, L. fucensis and D. globulus
moved to areas with temperatures above 5°C, while
P. variabilis showed no preference. In species-specific
temperature preference experiments, L. fucensis and
D. globulus aggregated between 5 and 13°C, while P.
variabilis occupied areas with significantly lower temperatures
from 4 to 11°C. These experimental temperature
preferences correspond with their thermal
environments. Upper temperature limits are moderate;
extreme abiotic variability in higher temperature fluids
may constrain these 3 species. We conclude thermal
conditions are a primary determinant of habitat selection,
thereby driving gastropod abundance patterns.
However, other factors likely contribute. Space competition
nearest vent flows may result in the displacement
of individuals of these species to low quality habitats.