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Punta Gorda is a remote coastal promontory in southern Humboldt County. Ocean conditions off Punta Gorda are known for their frequent strong winds, rough seas, and strong currents. Two square miles of ocean off Punta Gorda were selected as a marine ecological reserve as a result of the Proposition 132 selection process. Last year, we obtained a grant to fund a three-year habitat and resource inventory of Punta Gorda Ecological Reserve (PGER). In 1997, we focused on mapping bathymetry and substrate as well as on providing initial samples for abalone DNA studies. California Department of Fish and Game (CDFG) staff, including Konstantin Karpov and Douglas Albin, provided coordination, logistics and vessel support for the field portions of these assignments. Vessel support was supplied using both a CDFG vessel and a leased commercial urchin boat, the FV Miss Michele owned and skippered by Jon Holcomb, whose marine experience contributed greatly to successful completion of our habitat inventory work. In July, we also began aerial photo reconnaissance to characterize environmental conditions in the reserve. Seasonal photographs will provide information needed to quantify any surface canopy of annual bull kelp (Nereocystis pyrifera) and document seasonal turbidity patterns. Over the next two years, aerial photographs will be taken on a quarterly or tri-annual basis. In late August, temperature recorders programmed to log sea temps
for 662 days at 2 hour intervals were deployed, and a single exploratory
dive to 8.1 meters was completed. Strong currents (up to 3 knots)
were recorded during this time period. Bathymetry and substrate field work were also conducted in late August by Chris Malzone and Pat Iampietro of ABA Consultants, aboard the FV Miss Michele. Skipper Holcomb was required to steer 30 precise track line headings in the reserve, while Chris and Pat operated sidescan “Roxann” sonar (which estimates substrate type) and differential GPS. Post-processing of the data has already begun. When completed, the Department will have detailed bathymetric maps of the reserve sea floor, with overlays that categorize geomorphic features, as well as digital, computerized Geographic Information System (GIS) maps for detailed analysis of habitat types within PGER. Ground truthing of bottom types will be conducted during years two and three of the project. Abalone DNA work at PGER was initiated by Dr. Vicky Kirby, who has collected over 400 red abalone tissue samples from nine sites along the California coastline, and from two aquaculture facilities. Dr. Kirby began studies to determine what kind of tissue can be collected in the field for microsatellite analysis. Microsatellites are DNA sequences which provide information on genetic linkage, mapping and individual identification. Dr. Kirby’s study was the first to successfully identify microsatellites in red abalone. Douglas Albin and Warden Larry Bruckenstein collected the first
tissue samples from adult red abalone at PGER. These samples may be compared
to abalone from other biogeographical sites to isolate genetic markers
belonging to distinct populations. As DNA technology advances, the tissue
samples collected at PGER may prove invaluable for future population studies
of California red abalone.
ABOVE: Sidescan sonar image from about 20 m depth in PGER.
Lighter areas are rock outcrops. Dark, flat areas are fine sediment such
as sand or mud.
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