The Influence of Temperature on the Rocky Intertidal Zone

Abstract

The rocky intertidal zone is a dynamic ecosystem that is highly vulnerable to the effects of climate change through both increased water temperature and exposure to extreme weather events during low tides. This ecosystem is home to several species including the habitat forming California mussel and refugia algal species: Endocladia muricata and Silvetia compressa which may be sensitive to thermal shifts. In order to achieve an understanding of these dynamics, the establishment of long term monitoring is essential to track patterns of weather and species cover over time. A key aspect of long-term monitoring is understanding what causes changes in community structure. In order to better understand how temperature affects rocky intertidal species, temperature loggers on each site are co-located with biological point-intercept species plots. Using 7 years of temperature data from two sites on Santa Rosa Island, we investigate thermal trends and extreme heat as related to rocky intertidal biological abundance and diversity.

The two sites on Santa Rosa Island being studied are Bechers Bay (34.00, -120.04) and Skunk Point (33.99, -120.00). Each site contains a total of 20 point-intercept plots with an associated iButton thermal logger (5 per intertidal zone – low, mid, high, and splash). Each zone has unique temperature characteristics due to different emersion rates during high and low tides, but each of the 20 plots also host their own unique microhabitat that is independent of the others. Therefore, the impact of temperatures on both zones and individual plots can be made. Correlations between species abundance and diversity with temperature will be discussed in order to predict how a warming climate may affect rocky intertidal species assemblages in the future.

Details

Session 1

11:15am – 12:30pm

Del Norte Hall

Room B: 1545