Central California Council of Diving Clubs, Inc.

Abalone Armageddon

We were going to call this page 'Ab Gab' in order to pass on divers' observations regarding abalone, kelp, and purple sea urchins. But after accumulating some of the material there is no doubt that this treasured California resource is in dire straits. An excellent summary of the situation "Collapse of the kelp forest?", written by Mary Callahan was published in the Santa Rosa Press Democrat in April, 2016, with its astounding photo of an abalone on a runt of a kelp stalk. A copy may be read from the San Jose Flipper Dippers May newsletter at Collapse.

Abalone harvesters during the first 3 months of the season reported numerous shrunken feet inside of large shells. Rocky areas devoid of kelp but with thousands of small blue sea urchins were described in both Sonoma and Mendocino Counties.

On the August first reopening of abalone season the San Jose Flipper Dippers on an outing to Timber Cove reported mixed results. Carl Tuttle summarized for the club that some areas had healthy abalone in kelp beds, areas with a small amount of kelp had some abalone, while areas that we were covered with purple sea urchins had no kelp with very few to no abalone. One member reported seeing a purple sea urchin attached to the top of a short stalk of kelp. Upon cleaning the abs it was observed that those taken from the more sparse kelp areas and those from non-kelp areas were substantially smaller. It appears that the abs in some areas may not be getting enough to eat.

Abalone diver John Salisbury, diving south of Mendocino on August 12-13, came across a dead abalone on the bottom, foot side up, that had apparently died of starvation. He reports that the body was shriveled and hard as a tennis shoe sole. He used the word "depressing" to see this. The bottom, lush with kelp in previous years, was barren except for many small sea urchins. An area about 100 yards away still had a good stand of kelp with a lot of nice abalone.

On the weekend of the 13-14th a club that wishes to remain anonymous stayed at Ocean Cove and gave no word as to where they dove for abalone. They found more than one 10" abalone, in shell size, but the meat was small. The abs were starving. Some vertical walls were covered with the big ones as they seemed to be leaving their crevasses in search of food. Also noted were abs on top of abs as one eats the algae off another. The operative descriptive word here was "pitiful".

In the August, 2016, issue of MBNMS Newsletter, Capt. Phil Sammet has some alarming observations from the Point Arena and Fort Bragg areas, noting the marked changes which have occurred over the last two seasons. The small purple urchins have covered many miles of reefs (Phil says over 100 miles!), eating every bit of kelp. Abalone, as we all know, rely on kelp for their main diet, and are starving as a result. His report follows.

The Rockfish Files

by Capt. Phil

I wanted to write a little something about my recent visits to Point Arena as well as Fort Bragg. I was there as diving support for Reefcheck. I also took some time to do a little diving on my own. I have been diving in the Sonoma and Mendocino for many years as I am sure many of you have. Last season and this season have marked a major change in the north coast environment.  Urchins have covered the reefs for over one hundred miles of the north coast. The small purple urchins (Strongylocentrotus pupuratus) eat kelp if it is hungry and at this time they have eaten every bit of it, leaving none. 

 

 

 

The abalones are desperately looking for food. They have resorted to eating red algae on the backs of their fellow mollusks. Because otters have been removed from the north coast for so long, people have been the keystone species there, removing urchins commercially and abalone recreationally. The problem is we are not doing a good job. The urchins are not commercially viable at present, due to size, and we restrict the take of abalone (unless you are a poaching flash mob at low tide) which I have seen is now doing a fabulous job restoring balance on the reef by taking everything in sight. There is a total system collapse up north that has not yet hit rock bottom. Will kelp grow back? Nope, not until the urchin population is reduced. Will the abalone die? Maybe, I don't know how long they can hold out. Will the urchins eat themselves out of existence? I don't know. I must say that I am happy to be back in a healthy kelp forest with otters that know how to treat an urchin. We as a society choose the environment we work and live within, in MBNMS we have a great balance. A vibrant kelp forest, The great whales and Well managed fish stocks.  But remember this is a choice. It requires work

Capt. Phil

What is happening reminds us of the Oklahoma dust bowl of the 1930s where droughts were followed by plagues of grasshoppers that ate any remaining vegetation and then the winds blew the dry soil away. The farmers who relied on their crops had to move or die. For several years we've had a perfect storm of oceanic changes which have shrunk the kelp forests and the currents are now bringing plagues of sea urchins which are eating any remaining vegetation. Unfortunately the abalone who rely on the kelp are not able to move so will die.

Lastly, CDFW published a summary article of conditions that have led up to the current dire situation. To access that, copy and past this address in your browser: https://cdfwmarine.wordpress.com/2016/03/30/perfect-storm-decimates-kelp/.