Northern California Marine Environment Status with Dr. Jan Freiwald of Reef Check
by David Chervin
At the Aqua Tutus May membership meeting, Dr. Jan Freiwald, Executive Director of Reef Check, presented an analysis of the status of the northern California marine environment.
At the Auqututus May membership meeting, Dr. Jan Freiwald, Executive Director of Reef Check, presented an analysis of the status of the northern California marine environment. We have seen massive increases in purple urchins over the last few years which led to the closure of the Abalone fishery for the 2018 season. Dr. Freiwald presented data gathered by Reef Check volunteers that describes the current situation and discussed the possible future status of California reefs.
Reef Check California trains volunteer SCUBA divers to perform scientific surveys to inform state agencies approaches to managing the California marine environment. Reef Check is focused on research to promote science based decision making and foster public awareness.
Reef Check California is a program of Reef Check Foundation which was founded in 1999 to promote research and awareness of coral reef environments. Reef Check has trained local inhabitants in 50 countries to monitor their coral reefs. In 2006, Reef Check California was founded to focus on monitoring California rocky reef environments. Reef Check California gathered baseline data in advance of the creation of California Marine Protected Areas (MPAs) and has been monitoring the effect of the MPAs ever since.
Dr. Freiwald joined Reef Check in 2008 to direct Reef Check California and was promoted to Executive Director in 2018 to run the Reef Check Foundation including Reef Check California.
Reef Check California volunteer SCUBA divers take a two weekend course of classroom, pool and open water sessions where they learn how to identify 73 indicator species and conduct the Reef Check scientific research protocol. Volunteers are tested at the end of the course before they are certified to gather data. Each year, returning volunteers do a day of diving where they are re-tested and re-certified to collect data for the upcoming survey season. In 2017, Reef Check volunteers completed 117 surveys at 104 sites from the Oregon to Mexico borders.
Reef Check surveys show the effects of environmental events on California’s marine environments. In 2014, the onset of a virus led to the sea star wasting disease that dramatically reduced sea star populations. Purple urchin populations began to increase and the kelp forest started to decline, possibly as a result of increased ocean temperature. Abalone populations counted by Reef Check divers initally increase in 2014. In the following year , purple urchin populations continue to increase and kelp density further decreased. Abalone populations were now declining.
By 2017, Reef Check has identified multiple sites in Mendocino and Sonoma Counties that have become urchin barrens with little or no kelp forest. About half the sites in Monterey County such as Coral Street and Lover’s Point have become urchin barrens while the Big Sur coast seems unaffected so far. Lately, we are seeing a strange standoff between urchins and kelp at many Monterey sites.
Based on analysis of populations in Mendocino and Sonoma, it appears that abalone have moved from deeper waters not surveyed by Reef Check to the shallows as kelp populations decline dramatically. In addition, we observed that the abalone weight and thickness was also reduced as a result of a loss of food supply. In 2018, abalone density was below the allowed threshold, and the California Department of Fish and Wildlife closed the abalone fishery for the 2018 season.
The future is not bright for California kelp forests and the abalone population. Based on the current data, the abalone fishery is not likely to re-open any time soon. Abalone are a notoriously slow growing organism and studies show that even after their food supply is restored in can take two years for abalone to recover to the point where they can reproduce.
Removal or culling of purple urchins may help restore the kelp forest environment. Culling efforts in a few test sites in southern California led to kelp recovery. A big effort is underway by commercial urchin and volunteer diver to reduce urchin populations in Mendocino and Sonoma. Over Memorial Day weekend, several tooters and other divers are meeting at Ocean Cove to reduce purple urchin populations. Reef Check will conduct surveys before and after the removal to determine the effect of these efforts.
The jury is still out on the future of our kelp forest environment. Urchin barrens may be a natural phenomenon as has been seen previously in Monterey in the 60s and 70s or this urchin invasion could be a result of global warming. Urchin removal may bring back the kelp forest of have unintended consequences such as the introduction of an invasive species that creates a more dire situation.