In a recent blog post, I spoke about my dives at “One Mile South” between El Capitan and Refugio State Beaches west of Santa Barbara along U.S. Highway 101. My last sport dive at that spot was in the summer of 1994, just before I moved to Alabama to teach at Troy University. Three years later, I returned to southern California to work as a social scientist for the Minerals Management Service where I re-established the long dormant Pacific Region’s scientific diving program. It was in that capacity that I visited “One-Mile South” for the last time to look for an elusive white abalone,, also known as Sorenson abalone (sp. Haliotis sorenseni).
How the Armor Rock Came to Be Placed
Santa Barbara County and other regulators had long insisted that the Exxon platforms in the Santa Ynez Unit be operated with electric power that was generated onshore and transmitted to the platforms via a subsea power cable. The quarry rock was placed over the nearshore portion of the cable route to armor the installation. The electrification strategy was thought to greatly reduce air emissions compared to electrical power generation from on-platform diesel generators. In the 1980s and 1990s, air emissions from offshore oil and gas facilities contributed greatly to the County’s air quality degradation. A special unit was created within the air quality management district just to address permits and monitoring from these sources.
Problems Under the Armor Rock Protection
By 2001, the power cable between Exxon’s Las Flores Canyon processing plant and the offshore platforms needed to be replaced. That operation required the removal of the overlying rock protection. A staff report by the California Coastal Commission framed the need for the dive.
“During a pre-construction biological survey in August 2001, the Applicant found what was believed to be a white abalone on armor rock about 50 feet from the end of the nearshore cable conduit at about 20 feet of water depth. The white abalone is a federally-listed endangered species with a historic range from approximately Point Conception on the north to Baja California in the south. (Note 1)
The white abalone is generally found in much deeper waters (80 to 200'); however, this individual was found in about 20 feet of water about 50 feet from where excavation work is proposed to allow cable removal and placement through the conduit terminus. (Note 2) The excavation work would result in turbidity, which would be short-term but could adversely affect the abalone.
Additionally, cable removal and placement, along with vessel anchoring in the vicinity, could result in abalone being crushed or being disturbed by any increased turbidity.”
Species Uncertainty
The NOAA website notes that the white abalone has “a thin, oval-shaped shell. The shell has a row of holes used to breathe, remove waste, and reproduce. The bottom of its foot—the muscle it uses to move and adhere to rocks—is orange. It also has a tan-orange epipodium, an extension of the foot with tentacles used to sense the surrounding environment.”
While this description sounds definitive, some species of abalone in the wild are difficult to positively identify, especially when the object is far back in a rock crevice. Some believed that the only way to positively identify the white abalone was to examine the foot for the most distinctive characteristics. Such an examination would require the abalone to be pried off the rock. However, removal and replacement of an abalone, even to positively confirm the species, could have been a violation of the Endangered Species Act if the abalone turned out to be a white abalone. In other words, we could only observe the abalone. The abalone could not be removed or disturbed in any way.
Because there was uncertainty as to whether the individual abalone was indeed a white abalone, California Department of Fish and Game biologist Ian Taniguchi was asked to do a follow-on survey to visually confirm if the abalone was indeed a white abalone. Ian contacted the Minerals Management Service to see if its dive team could assist with the survey. I had met Ian when we were divers participating on a National Park Service Kelp Forest Monitoring cruise a year earlier. Herb Leedy, the second MMS diver, was a wildlife biologist in the environmental and assessment study section.
I was excited to participate in this reconnaissance. The MMS dive team had recently been authorized. Up until that point our activities had been limited to training dives, a reconnaissance of the ocean-to-beach transition of a pipeline at Carpenteria pier, and assisting Channel Islands National Park in the underwater video program from the Anacapa Island landing cove.
The plan was for us to join Ian on Peter Howarth’s boat, which was normally used for marine mammal rescue response, for the trip out to the site. Ian had arranged use of the vessel. Once at the site, we would dive on the cable’s protective rock covering, locate the abalone, and complete our assessment. Our dive plan was quickly approved by MMS regional managers. On September 19, 2001, Herb and I met Ian and Peter at the Santa Barbara Harbor for a quick voyage to Las Flores Canyon.
The Dive
Tuesday, September 19, 2001, was foggy and overcast—the typical early morning Southern California marine layer. We boarded the boat at the Marine Mammal Center’s berth near Sea Landing at the Santa Barbara Harbor. The trip out to the location was uneventful. There was a slight chop on the surface easily handled by Peter’s boat. We motored up the coast past many of the places from which I made beach dives over the years. As we approached Elwood Pier and The Junkyard, I got a close look at the luxury Bacara Hotel.
Once on site, we quickly geared up to enter the water. I noticed that Ian used a horse collar buoyancy compensator—the hallmark of scientific divers trained in the 1960s and 1970s. Herb and I used the equipment that had been purchased for us by the MMS when the team was initially authorized.
Peter did not anchor the boat as part of the operation. Instead, we dropped a white marker buoy into the water. He would stationkeep in the area around the buoy and our exhaust bubbles, an operation known as “live boating.”
We entered the water as a group, briefly floated on the surface and descended to about 30 feet. We immediately located the armor rock reef and started examining the area for the abalone. We knew generally where the abalone had been located on the reef and concentrated on that area. I quickly located the abalone and banged on my tank with my dive knife to signal my two buddies.
The abalone appeared to be a white abalone. Herb also visually examined the abalone. Ian visually examined the abalone and took pictures with a Nikonos underwater film camera. We checked the area for any other abalones before surfacing. The entire dive lasted just over 30 minutes.
Peter backed the boat to our surface location. After confirming the engine was in neutral gear, we climbed onto the boat’s rear platform and ascended the ladder to the deck. We removed and stowed our gear as Peter headed the boat back to the harbor. We agreed that the abalone appeared to be a white abalone. Ian said the next plan would be to submit the findings to the State and await their further direction as to the best course of action.
The Aftermath
Herb and I returned to the office and filed the dive report with our findings. Ian emailed us the photographs of the abalone a few days later. (Unfortunately, I no longer have those images.)
A number of actions followed our reconnaissance dive.
In April 2002, Exxon-contracted marine scientists performed an expanded survey to determine if there were other abalone in the area that could be adversely affected by the project. According to the above mentioned California Coastal Commission staff report:
“The survey covered an area about 825' by 800' centered on the conduit terminus. The survey found 21 additional abalone in the area, one of which was thought to be a white abalone about 600 feet from the excavation area. The survey also found the shell of the white abalone identified in the August 2001 survey. The surveyors also observed a sea otter near the site and was believed the sea otter had eaten the abalone during the period between the two surveys.”
Final Thoughts
The preconstruction surveys confirmed my earlier description of the site as “abalone acres.”
The irony of a sea otter (an endangered species) consuming another endangered species (white abalone) is not lost on me. (Note 3)
Little did I know that this dive was my last dive as a government scientific diver. Shortly after the dive, MMS announced that the Pacific Region would undergo a 50 percent staff reduction and I transferred to the Alaska Region. My efforts to established an Alaska Region dive team proved fruitless.
Notes
Note 1.
The National Marine Fisheries Service had listed the white abalone as a federally endangered species under the federal Endangered Species Act on May 29, 2001. This action made it the first marine invertebrate listed as a result of human harvest.
Note 2
Marty
Snyderman in his 1987 book, California Marine Life, notes that the white
abalone is “the favorite of many ab hunters, being noted for their delicious
and tender meat….(W)hites prefer deeper, colder waters. In Southern California white abs are often
found at depths in excess of 100 feet, while in northern waters they are found
as shallow as 35 feet. Dennis Divins, the Diving Safety Officer at the
University of California Santa Barbara, once told me that while the white
abalone was generally found deeper than 100 feet they were not uncommon at much
shallower depths along Santa Barbra County’s South Coast. He thought this might happen because of the
upwelling of cold water in the area.
An environmental
impact analysis completed for the on-going project in 2013 by Exxon noted “this
species has occurred in shallower depths near its northernmost
limit…Specifically, localized mainland areas in the Coal Oil Point region, west
of Santa Barbara, have supported white abalone in water depths less than 60
feet (20 meters)…Speculation concerning reasons for its presence in shallow
water includes competition with red abalone (H. rufescens) and/or a
localized decrease in predation from sea otters without a concomitant increase in harvest…The vertical distribution limits may also be controlled by water temperature.” (emphasis added)
Note 3
Technically,
the sea otter should not have been there.
In the 1980s, the Fish and Wildlife Service translocated an number of
otters to San Nicolas Island. As part of
that program, the Fish and Wildlife Service promised to relocate any sea otter
found south of Point Conception and outside of San Nicolas Island translocation area, to the north of Point
Conception. The otters had other ideas
and expanded naturally into their historic range. The relocation policy, long abandoned to the
whims of nature, was only officially withdrawn a few years ago.
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