**This blog entry orginally appeared on the website oceanspaces.org.**/p>
It was a typical north coast cold and foggy morning as we arrived at the Trinidad boat launch to catch a ride to our research vessel (see Part I), which was anchored at the edge of Trinidad bay. While Trinidad bay offers good protection from northwest swell, the rocky reefs around the pier are too hazardous for a ship as large as ours to approach. Having just finished our underwater survey of the Point Saint George Offshore SMCA (see Part II), we were all a little groggy on this particular morning. As the last person arrived at 5:45 am, we boarded the small skiff and prepared to be lowered down the rickety tracks of the boat launch to the water. As we reached the water the captain said, “Give us a good straight push off the trolley so we don’t end up on the rocks. I don’t have reverse, so we only get one shot at this”. I speak for all of us when I say we were not expecting that. After taking the short taxi ride out to the boat, we boarded and prepared for the almost three hour transit to the Reading Rock SMR.
Located about three miles offshore of Redwood National Park, Reading Rock is a unique rock spire that rises up from the sea floor, producing an offshore rock that is visible from land. Sonar mapping of the sea floor around Reading Rock shows that it is surrounded by an area of rocky reef that gives way to vast stretches of soft bottom habitats. This island of rocky reef was to be our first dive.
We headed for the State Marine Reserve site first and launched the ROV into the water. As I descended the ROV toward the sea floor, visibility quickly began to diminish. Suspended fine sediments and marine snow created a thick fog like soup. Nearing the 60 meter depth, large boulders and rounded rock outcroppings barely became visible as the ROVs lights illuminated the darkness. I began to carefully maneuver the ROV through the labyrinth of rock structures and boulder piles, making my way along a pre-planned transect line.
Within the rocky reef, several species of colorful sea stars were observed on the sediment covered rocks. Aggregations of the club-tipped anemone and giant acorn barnacles were often found on vertical surfaces and under overhanging rock features, taking refuge from the constant deposition of fine sediment and detritus. Only on the tallest of rocky features were the white metridium anemones found. The usual cast of fish characters were also observed living within the rocky rubble. Lingcod and quillback rockfish were common, as were copper and yelloweye rockfish.
As I flew toward the edge of the rocky reef, boulders gave way to cobble, which gave way to gravel and then sand. Juvenile canary rockfish darted past taking only a moment to observe the bright lighted alien craft that had just come out of the darkness. Many species of flat fish lay motionless on the sea floor, camouflaged and awaiting prey. Only as the ROV moved over the top of them or after we took a photo for identification did they swim away.
Our survey lasted three days at Reading Rock and with rough weather quickly approaching we headed for Humboldt Bay to wait out the storm. I had a great time exploring this unique reef and especially enjoyed being able to finally share the experience with my son Paul. He joined our team for two days and had the opportunity to not only see what dad does, but also put all those years of playing video games to work and fly an ROV. Our next stop is to the south and it will be the most extreme marine environment we will survey on the north coast. Diving deep, we will explore the Mattole Canyon SMR.