Josh Russo: Purple Urchin and Abalone

  • Commercial urchin diver

By: Alan Throop (photo above ref. 10)

At the July 11 general meeting, Josh Russo spoke to us about the purple urchin and abalone problems that California has faced the past several years and what the Watermen’s Alliance (WA) is doing to help address these issues.

Josh Russo July 2019

Josh Russo speaking to club. (Credit: Linda Phillips)

Josh is president of the WA and has been a key driver to organize both recreational and commercial removal of the urchin overpopulation, to give the kelp and abalone population a better and faster chance of recovery. Josh is a very active in the Northern California dive community. Besides his activities with WA, he is on the board of directors of Diving For a Cause, an administrator on the forum, a member of the Solano County Dive Rescue Team and also does volunteer work with several other organizations that help people recovering from substance abuse. For the last six years has Josh has been sharing his passion for the ocean with new divers as an assistant scuba instructor and licensed guide for spearfishing and abalone diving. He also created a “mentor thread” on NorCal Underwater Hunters that helps new divers find an experienced diver that can teach them how to understand the regulations, dive safely and hunt effectively.

Josh mentioned interestingly that he has been diving for 20 years and got into diving when doing Physical Therapy after a motorcycle accident. The exercise and motion in the water when Ab diving helped his recovery and he enjoyed it so much that he got trained in SCUBA, began teaching, and has become actively involved in the regulatory aspects to protect and enhance the sport. His efforts to protect the resources and access for spear fishermen have followed from this.

Urchin problem

In 2013-14 a “sea star wasting syndrome” (SSWS) attached the sea star community in the North America Pacific Coast, including Northern California (1).  It caused massive die-offs in over 20 different species of sea stars that continues to persist. Similar die-offs had occurred in the 1970s, 80s, and 90s, but not at the magnitude and geographic extent of the “2013” event. It was initially thought to be due to a virus, but that is now NOT the case except for one important species –  the sunflower sea star (Pycnopodia helianthoides) …more on this in a moment.  So there is still a lot more to understand about this disease that continues to be a mystery after all these years.

A series of photos taken in Guemes Island, WA in June, 2014 over the course of only three days (see PDF newsletter). This shows how quickly SSWS can progress and how extensive the damage and eventual death is. The current die-off was first noted in June, 2013 along the Washington state coast during monitoring surveys. In August, divers reported massive die-offs of sunflower stars in Vancourver, British Columbia. In October and November similar massive die-offs were reported in Monterey. By mid-December, 2013, die-offs were reported in So Cal and by summer, 2014 SSWS had spread to Mexico and Oregon.  There is an interesting UC Santa Cruz website that shows long-term trends at monitored locations.

Sunflower star

Sunflower star, Ref: web.

Unfortunately, one of the first species to often succumb to SSWS is the sunflower star (photo). This large sea star, along with the ochre star (Pisaster ochraceus), are considered “keystone species” because they have a disproportionally large influence on other species in their ecosystem. In particular, the sunflower star is a key predator of sea urchins. As adults, they swallow the sea urchins whole and spit out the spines (2). With the absence of sunflower stars, the sea urchin population began to explode. The sea urchins, in turn, overrun and devour the kelp, destroying the kelp communities and leaving large “urchin barrens” where there were once prolific kelp forests.  Before 2013, NorCal Mendocino and Sonoma county waters typically had 1-2 Sunflower stars per 60 sq meters; in 2014 there were none. The 2018 diving season also had no reported sightings (2).

It is hoped that a natural recovery will allow the kelp to reseed itself, but the kelp propagates by dropping spores that float and then eventually settle on the bottom to grow (“recruitment”). However, with an overpopulation of urchins this could be problematic since the urchins also eat the spores (2). In particular, Bull kelp needs to spore within 2 years or it cannot reproduce itself.

Aqua Tutus Diving Club at the Purple Urchin Removal Event

Aqua Tooters participating in the FIRST recreational urchin takes, May 2018. Ref: unknown.

An added factor to all this is that the Purple Urchin can exist for many years with little food. It’s a voracious eater, normally feeding on algae on rocks and kelp. Its 5 tooth-like plates near the mouth can even drill into rocks and steel pilings. When these food sources are gone, it can go into a type of dormant state  where it can live for many years and then awaken when its food source returns. This makes recovery of the kelp forest problematic after such a severe over-population event. In addition, the purple sea urchin normally is commercially taken and exported as “uni” (more on that below). However during these severe events when it goes dormant, the gonads shrink and they become unviable for export. This suggests that the current large over-populations of urchins need to be removed to improve the chances and to help speed the recovery of the kelp forest and abalone resource.

It should be mentioned that, about this same time in 2013, the kelp forest faced other pressures.  At that time a persistent high pressure system settled in over the Pacific Ocean. This, coupled with the very-strong El Nino of US west coast over several years, producing warm water along the coast. The warm water not only stressed the kelp but also reduced the phytoplankton that is the underlying ecological basis 2015, impacted the entire for the kelp forests. This “perfect storm” of SSWS, climate anomalies, and predation laid waste to much of the kelp along the west coast in a manner not seen in decades, if ever.

Abalone issue

An additional pressure on abalone and the marine environment that complicated the issue was the “Abalone Withering Syndrome” (AWS).  This was first described in 1986 (3).  This disease attacks the lining of the ab’s digestive tract, inhibiting the production of digestive enzymes. To prevent starvation, the ab literally consumes its own body mass, so that its foot withers and the ab finds it difficult to hold to rocks, making it more prone to predation, or just prone to starvation. It was first observed in the northern Channel Islands. This further enhanced the impact of SSWS on the ab population. In 1997, it was determined that numbers of abs in SoCal were so small that some species might become extinct, and the California Department of Fish and Wildlife (DFW) closed both commercial and sport taking of abalone.

DFW logo

Josh got involved with the abalone problem after the DFW reduced the take in NorCal in 2013. DFW at that time hoped that that the ab population would rebound.  Unfortunately, it did not.  In 1999, it issued the Marine Life Management Act (MLMA), aimed at limiting the take until it is proved that the fishery could be sustained. The DFW is not developing a Red Abalone Fishery Management Plan (FMP) for the north coast.  Josh, representing the WA, is advocating for continued take by recreational divers for research (which they then get to eat).

Josh said that currently there are still very few abs in Sonoma county except in isolated spots. Mendocino county is not as bad, but still has a distinct lack of abs that cannot support any level of recreational take. The goal of the WA work is to again return these areas to a level of abalone population that can support recreational take.


WA concern is that the sport and near-shore fisheries may decline even further or disappear altogether if the current state continues. Rather than “watch and wait”, the have taken a pro-active approach – working with the DFW – to explore some options to help remove the sea urchin over-populations.

Purple urchin event

Urchin take. Ref 10.

One way to address the urchin barren problem and help the kelp forest ecosystem re-establish itself is to remove the over-population out of equation – at least in certain areas. This might be accomplished by either/both recreational or commercial removal.  The DFW limit for Purple Urchin recreational take was limited to 35 urchins/day  for recreational take prior to 2013. Due to work by WA and others to help mitigate the urchin problem, this limit was raised to 20 gal/day in 2018 and they were allowed to crush the urchins OUTSIDE of the ocean to reach the 25 gal limit. The limit has again been raised to 40 gal/day in 2019.

Josh, with the WA, has been using these new regulations to provide a proof-of-principle to the DFW that taking the urchins by commercial and recreational harvesting can have a measureable impact on the urchin population and thus give the kelp ecosystem (and abalone) an opportunity to recover.  They have now organized a number of recreational urchin-take events (of which Aqua Tooters have participated, photo) at several locations: Ocean cove, Caspar, Albion, Noyo harbor and Van Damme. They were typically able to remove about 1000 pounds from a recreational dive weekend. These recreational takes are in areas that are too shallow for commercial takes and are used to demonstrate to DFW that these takes are both meaningful and sustainable.

Four steps are required for this proof-of-principle:

  • First, can the urchins effectively be removed? The California Reef Check organization surveys the sites before and after the take.
  • Second, Do the urchins stay out?  DFW & Reef Check continue to survey the sites to document the populations. So far both agree that they have not returned.
  • Third, Do they return? By subsequent surveys, Reef Check determines that this area has clearly remained with a reduced-population of urchins.
  • Fourth, Does the ecosystem return? DFW looks for observation that this area sees a restoration of kelp and that the abalone is returning.

To date, steps one to three have been completed. These events have established that a “clear line” has been observed in each cove, beyond which the urchins have not moved back into the cove.

In additional to recreational takes, WA is working to establish that commercial diving can also impact the urchin population and are trying to establish a commercial market for the urchins on an ongoing basis. WA raised $130,000 to test the impact of commercial takes. A local commercial diver near Fort Bragg, Jon Holcomb, designed an underwater vacuum for the large-scale removal of urchins (photo). They were able to demonstrate that the commercial harvest by the single diver could be 500-1000 pounds/day, and that it would cost about $500/day to operate the vacuum.  WA has to-date been unable to find a commercial diver in Mendicino for similar harvesting.

In NorCal, there has always been some commercial harvest of purple urchins for “uni” (photo), the Japanese name for gonads of the sea urchin. It’s very trendy (apparently), with a creamy texture that tastes like the ocean by not fishy and is used for  sushi, sandwiches, and pasta topping in trendy restaurants (photos). However, due to the unnatural explosion of the urchin population due to SSWS, the urchins themselves are small and their commercial value has decreased … along with the profitability of taking them commercially.

They are also trying to establish a commercial fishery market in Sonoma county for urchins – to support ongoing commercial takes of urchin – using crushed urchins as a fertilizer (which also has useful pesticide properties). This would generate “sub-prime” urchins. At the same time, they are trying to establish a “prime uni” market for healthy marketable urchins for both local and foreign consumption. They currently have setup six demonstration  pens at the Bodega Marine Lab where they raise prime-quality urchins. The urchins are fed kelp pellets and become eatable size in about six weeks. Eventually they would hope to have 100’s of pens, with sales going back to support commercial divers to remove the sub-prime urchins on an expanded and on-going basis.

So far, by their combined efforts of recreational and commercial takes of urchins, WA has removed over 58 tons pf urchins. They have been able to demonstrate that these takes can remove enough urchins from an area of impact the number of urchins and that they can keep the urchins from returning. They are hopeful that this season or next they can observe and demonstrate that both the kelp and abalone are returning to these areas. Once that is accomplished, they can expect to obtain funding to expand this work.

We appreciate that Josh took his time to share his work with us and that he and Watermen’s Alliance are so committed to helping the ocean and fishery recover from the threats they face.

(Editor’s Note: Even as this article was written Josh was in Washington, DC, along with Ocean Conservancy and California fisherman, to meet with about a dozen congressmen & congresswomen or their staff, including our representative Barbara Lee in support of the Magnuson Stevens Act (11) and California SB-69 Ocean Resiliency Act of 2019 (12). SB-19 provides science-based management of our oceans to address impacts of acidification and other issues due to climate change. It also provides $3.5M for kelp restoration statewide. See the references at the end to read up and then please send an email to to support SB-19; please mention Josh’s name in the email so that they know he/others are representing our interests. In this article you will hear about the hard work that Josh and these organizations are doing to protect our oceans, so please help them to help us all and our oceans by sending a simple email.)












11. Magnuson Stevens Act, 2017; Fishery Conservation and Management Act:

12. SB-69 , Ocean Resiliency Act of 2019: