Argyle Creek is a unique "subtidal" habitat on San Juan Island.  The creek is a narrow conduit that runs between two saltwater habitats: Argyle Lagoon and North Bay.  The lagoon is filled by way of the creek daily as the tide rises and water runs into the lagoon, and then is partly emptied as the tide recedes and water runs back into the bay.  As a result, the creek never runs dry, and receives daily input of ocean water, which can carry in many of the planktonic larval stages of organisms that normally settle in subtidal benthic habitats.  Subtidal organisms can therefore be found in close proximity to intertidal organisms.  These conditions provide the professional or amateur biologist with access to an unusual mixture of animals at relatively shallow depth--at the lowest tides, the depth of the creek is only about 10-20 cm along its thalweg .  This habitat is also of special interest for its many unique physical aspects, including daily temperature fluctuations, bi-directional water flow, and wide daily velocity range in a saltwater environment.

The main goal of this project was to examine patterns of animal diversity in relation to physical factors that influence this unusual habitat.  To characterize the habitat, we first divided the creek into four zones, and then surveyed heterogeneous patches within each zone.  To link to detailed information and maps of each of the distinctive zones, and to read about other aspects of Argyle Creek, follow the links below.

Additional Links:
Glossary of Selected Terms
List of Organisms Recorded at Argyle Creek