Type of Presentation

Oral

Session Title

General Marine Habitat

Description

The rocky intertidal summer temperature profile of Bridget/Sunshine Cove in southeastern Alaska is more variable than occurs on San Juan Island in the Salish Sea. Maximum summer temperatures are as high at the Alaska site as on San Juan Island but are also more variable due to a high number of days with rainfall. The 5 hour high emersion temperature tolerance of the low intertidal Nucella lamellosa (29.6oC), mid intertidal N. lima (31.4oC), and high intertidal Littorina sitkana (41.5oC) varied directly with their intertidal position. However their dessication tolerance was minimal, 2.9 days for N. lamellosa, 2.2 days for N. lima, and 3.0 days for L. sitkana, and did not vary with their intertidal zonation pattern. The high emersion temperature and desiccation tolerance of the five species of gastropods on San Juan Island (Nucella lamellosa, 30.9oC and 3.8days; N. canaliculata 31.0oCand 2.7 days; N. ostrina , 33.8oC and 2.1 days; Littorina sitkana,41.0oC and 5.2 days: and L. scutulata, 40.6oC and 6.8 days, varied directly with their intertidal position. The high temperature tolerances of the gastropods on San Juan Island lie near the maximum air temperature to which they are exposed for a significant period of time during tidal emersion rendering the snails susceptible to mortality due to increases in emersion temperature with climate change while gastropods in Alaska are not likely to suffer mortality due to summer emergence temperatures. Natural selection in gastropods has not favored desiccation tolerance in Alaska because this site lies in a temperate rain forest whereas San Juan Island exhibits an arid environment during the summer.

Comments

Keywords: Rocky intertidal gradients, gastropods, temperature tolerance, desiccation tolerance, Nucella, Littorina

This document is currently not available here.

Share

COinS
 

Effects of rocky intertidal thermal regime along the Inside Passage between San Juan Island in the Salish Sea, WA and Bridget/ Sunshine Cove, AK on the high temperature and desiccation tolerance of gastropods.

2016SSEC

The rocky intertidal summer temperature profile of Bridget/Sunshine Cove in southeastern Alaska is more variable than occurs on San Juan Island in the Salish Sea. Maximum summer temperatures are as high at the Alaska site as on San Juan Island but are also more variable due to a high number of days with rainfall. The 5 hour high emersion temperature tolerance of the low intertidal Nucella lamellosa (29.6oC), mid intertidal N. lima (31.4oC), and high intertidal Littorina sitkana (41.5oC) varied directly with their intertidal position. However their dessication tolerance was minimal, 2.9 days for N. lamellosa, 2.2 days for N. lima, and 3.0 days for L. sitkana, and did not vary with their intertidal zonation pattern. The high emersion temperature and desiccation tolerance of the five species of gastropods on San Juan Island (Nucella lamellosa, 30.9oC and 3.8days; N. canaliculata 31.0oCand 2.7 days; N. ostrina , 33.8oC and 2.1 days; Littorina sitkana,41.0oC and 5.2 days: and L. scutulata, 40.6oC and 6.8 days, varied directly with their intertidal position. The high temperature tolerances of the gastropods on San Juan Island lie near the maximum air temperature to which they are exposed for a significant period of time during tidal emersion rendering the snails susceptible to mortality due to increases in emersion temperature with climate change while gastropods in Alaska are not likely to suffer mortality due to summer emergence temperatures. Natural selection in gastropods has not favored desiccation tolerance in Alaska because this site lies in a temperate rain forest whereas San Juan Island exhibits an arid environment during the summer.