Translocation, Homing Behavior and Habitat Utilization of Groundfishes Around Offshore Oil Platforms in the East Santa Barbara Channel. Final Report

摘要

There are 27 oil platforms (23 Federal, 4 State) offshore of the southern California coast from Point Arguello to Huntington Beach. In the near future, several deepwater platforms may be slated for decommissioning. However, California's decommissioning policy currently requires full removal, which can have detrimental effects on the local populations of marine life associated with the underwater structure, as explosives are often used to separate the vertical stanchions below the seafloor. Using non-explosive methods, when technically feasible, still removes long-standing habitat and the entire biofouling community. Of particular concern are the rockfishes, whose populations have been depleted due to overfishing on natural reefs. However, submersible surveys conducted over the past 13 years by Love et al. (2003) have shown significantly higher densities of larger adult rockfishes residing around oil platforms compared to nearby natural reefs. Platforms provide complex structure spanning the depth of the water column, which provides habitat for recruits in shallower depths, and larger individuals ii toward the base. Furthermore, fishing within and around the structure is difficult and sometimes restricted. As a result, platforms function like de facto marine reserves.