Recovering Black Abalone: Their Roles in Intertidal Ecosystems and in Ours

After Withering Syndrome devastated black abalone populations in Southern California, an interdisciplinary team teamed up to figure out how to save them. Theodora Mautz speaks with a handful of experts on strategies, lessons learned, and next steps for black abalone recovery. In this second episode of a two-part Natural Laboratory podcast series on black abalone, join us as we learn about what happened next to this resilient species, and why we should care.

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TRANSCRIPT:

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[Ambient intertidal sounds]

Theodora Tong Mautz: You're listening to the Point Reyes National Seashore Natural Laboratory Podcast, located on Tamál-Húye, the lands of the Coast Miwok. I'm Theodora Mautz with Point Reyes National Seashore Association, nonprofit partner to the National Park Service.

[Ambient intertidal sounds]

TTM: This is the second part of a two-part podcast on black abalone, the marine snail that lives in the area where the sea meets the land, called the intertidal zone, off the coasts of California and Baja California, Mexico. Let's dive back in where we left off: at a dangerous point for black abalone, where populations in Southern California were almost completely wiped out by a disease called Withering Syndrome in the late 1980s and early 90s. Things got so dire that they were added to the Endangered Species List in 2009.

At that point, it became clear that something needed to happen, quickly, to save the black abalone from extinction. Enter Susan Wang, the Black Abalone Recovery Coordinator for National Oceanic and Atmospheric Administration, or NOAA, Fisheries.

Susan Wang: I was part of a team to evaluate the status of black abalone. And we eventually, of course, decided to list black abalone as endangered under the Endangered Species Act. And so, following that, we worked on critical habitat. And then since then, I've mostly been working with a team to develop the recovery plan for black abalone, and we finalized that last year in 2020, and so now we are currently in the phase of recovery implementation, so taking that plan and prioritizing the recovery actions.

TTM: The recovery of this species is so important that there is a whole team dedicated to it. When most Bay Area residents hear the term BART, they think about the San Francisco subway system. But to a dedicated group of collaborative researchers, BART also stands for the Black Abalone Recovery Team. Susan now leads BART, and here's what she said about their work:

SuW: So, this is a team that's been formally appointed by NOAA Fisheries, and it includes I think 9 partners that are representatives of federal agencies, state agencies, universities, as well as other nonprofit entities, and also one of them is also from a consulting company. So, these are all black abalone experts and experts in the field of monitoring and recovery and outreach and education. And so, this team has been formed to advise NMFS or NOAA Fisheries on recovery implementation.

TTM: NMFS is the National Marine Fisheries Service.

SuW: One of our recovery actions is to restore and re-establish populations where they've declined because of disease, and so the main focus there is translocation: so taking abalone from healthy populations and moving them to these areas where there are no more black abalone right now, or where the populations have declined, and re-establishing and restoring those populations. And so, developing those plans and implementing restoration efforts, as well as learning and coordinating with our partners in Mexico, because they're actively doing that work right now, and then also ongoing studies on genetics and disease, and then working with enforcement and outreach and education partners to really get the word out there about black abalone and help the public see ways that they can really be contributing to black abalone recovery efforts.

TTM: Susan mentioned translocation as a key recovery action. The reason it might work is because in northern populations of black abalone, or further north than Point Conception, Withering Syndrome did not affect those populations. That doesn't mean that the bacterium, a type of Rickettsia, isn't there: in fact, when researchers sample black abalone from any population along the coastline, every single one has the bacterium that causes Withering Syndrome. Here's Professor Pete Raimondi, Professor of Ecology and Evolutionary Biology at University of California Santa Cruz, discussing how that works:

Pete Raimondi: And so, the real question isn't whether it's got it or doesn't have it, it's why and when it's going to go rogue, meaning it's going to become really problematic and lead to the death or really a lot of disease in the animal. It's kind of like people, people have got all sorts of things on them that are under control, like all sorts of bacteria are all over you, Staph is all over you. But for most people, it's not an issue. But if you get compromised in some way, or if you get stressed, then it can become an issue. And that's the same thing with abalone. We think that every one of them has got Rickettsia, but it doesn't really cause problems except under certain stressful conditions.

TTM: One of those potentially stressful conditions is warmer water temperatures. That could explain why black abalone populations further north aren't dying from Withering Syndrome. And it checks out – Steve Whitaker, a marine ecologist working at Channel Islands National Park, told me that he started seeing some populations of black abalone rebound in one site on the Channel Islands. But then, in 2015, two things happened that significantly raised water temperatures.

Steve Whitaker: We had a combo effect: we had not only one of the strongest El Niños on record occur during that year, but during the same period of time, we had something called the "warm water blob" and that was somewhat of a mystery at the time as to why it was caused, but it was this giant body of water that was much warmer than the surrounding areas, and then that warm water blob drifted around throughout the North Pacific Ocean. And in combination with the El Niño, really increased the water temperatures, which then had that ill effect on the black abalone, as well as the other organisms. It's not good for virtually anything in the ocean except humans bathing on the seashore, you know, we like the warm water. But everything else doesn't.

TTM: And this 2015 event once again devastated the black abalone populations at the Channel Islands. What that means is that global warming poses a threat to black abalone because of rising ocean temperatures. And that was sad news to me, because everything else about black abalone is unusually resilient against extreme changes in climate, just by being able to survive in the intertidal zone. Both Susan Wang and Professor Raimondi spoke to me about this:

SuW: What a tough environment that is! And that's where they live, you know, they, they're a marine snail, yet they can stay out of the water for hours in a day in the sun, and you know, they're just amazing creatures and really interesting how they can stand—they're tough— so they can stand all of this.

PR: It's resilient to things that ordinarily you would think would be problematic, and that may be problematic in the future with respect to climate, which are things like increase in temperature, changes in pH, oxygen, and that's because it experiences all those things almost on a daily basis, you know, because it's in the intertidal. Things get hot, they get cold, they can go low pH during upwelling, they can go low oxygen during cold upwell periods. So, there's a lot of things that you think are going to be problematic in the future because of climate change, they're already adapted for, and so they're unusual in that sense.

TTM: So, figuring out how to build back a population of black abalone that are resilient to Withering Syndrome and its links to climate change is the next big step. There's actually another aspect of climate change that has had a dangerous impact on black abalone populations, and it's not an intuitive one: it's big forest fires. Fires leave a ton of debris behind them, and in summer 2020, there were two very large fires in Big Sur, California. These were followed by a series of heavy storms in January 2021, which caused massive debris flows that traveled down to the ocean. This was disastrous news for BART, because 70% of healthy black abalone live around the Big Sur area. And this was supposed to be the population that formed the core group for recovery of the species. A team led by Professor Raimondi and graduate student Wendy Bragg went in and had to carefully dig through sediment and debris to rescue black abalone and translocate them safely to a lab. They kept them in the lab until a few months ago, when they were translocated back into the field. While this certainly demonstrates how much havoc climate change can wreak on black abalone, it also has a lesson of hope. Researchers rescued hundreds of black abalone successfully from the debris, kept them in the lab for months, and most of them survived to be released back into the wild once the danger had passed. In the coming years, BART will be able to apply the lessons learned from the Big Sur rescue to other black abalone translocation efforts.

We talked a little about the importance of black abalone in the last episode, but let's connect that to conservation efforts. Why are so many different people, from academic researchers to federal agencies, to even, as Susan Wang told me, guitar companies, so invested in protecting these snails? Well, the guitar companies can use abalone shells in their instruments, but in the other cases, it's less straightforward. Let's start with the ecological perspective. H