At the end of our long field season in the Galapagos Islands this summer, I felt like I hadn’t had my fill of diving and so I flew back to the west coast for a week of collaborating with the Channel Islands National Park in southern California. There I joined director Dave Kushner and staff Josh Sprague and Kelly Morse on the yearly kelp forest monitoring project. One of the longest of its kind, this project has yielded one of the longest running marine ecological datasets in the world, dating back over 30 years. Such a timescale of high-quality data on fish, sessile and mobile invertebrate, and algal abundance, size, recruitment, and diversity is an invaluable tool for defining relationships between fishing, reserve protection, and environmental oscillations as drivers of ecosystem structure and functioning.
I saw many parallels between the yearly monitoring work that we do in the Galapagos and the kelp forest program, but the scale of things was much larger: they monitor 32 sites every summer, taking copious amounts of information from multiple 100 x 20 transects at each site, in addition to recruitment modules and roving fish counts. I held my own and was able to contribute valuable data, and I also got my first taste of a California kelp ecosystem, one of the most productive and diverse in the world. In contrast to the New England kelp forests, which reach a maximum canopy height of about 20 feet, these giant kelp (Macrocystis pyrifera) can grow as much as 2 feet per day and reach maximum heights of 150 feet!
Needless to say, this immense 3-dimensional habitat houses a wide variety of unique, and sometimes familiar, marine life. My first incredible underwater encounter was with a giant black sea bass, a 7-foot behemoth that stood as an example of just what the ocean is capable of producing if we let her be. This amazing fish circled us curiously for about 20 minutes, allowing me to videotape it closely, I even got shots of the parasitic copepods covering it's face and a couple good shots showing divers alongside it for scale. Just a beautiful, powerful animal, what a treat.
I also took some cool film of a California sheepshead wrasse eating a large red urchin. It acted similarly to the triggerfish of the Galapagos, biting into the urchin test and scooping out the insides. Instead of hogfish circling to steal the prey, this wrasse had to deal with dozens of señoritas, small elongate wrasses that were able to get into the bite holes that the sheepshead had made and eat out all the meat before the sheepshead really even had a chance to get it. Very similar interference competition to what we see in the Galapagos, increasing handling time and decreasing the caloric reward for predation, and thus increasing the number of urchins needed to be killed in order to survive.
The Channel Islands are an incredible place and I highly recommend a visit for anyone who loves marine life. Completely worthy of designation as a National Park, I hope that this ecosystem remains healthy and protected long into the future.
Follow the Witman Lab's adventures, on land and at sea @witmanlab on Instagram and Twitter!