San Diego’s Climate Crisis: Oyster Hatchery Challenged By Warming Ocean
Speaker 1: 00:00 And we continue covering climate. Now on mid day edition this week, KPBS is joining hundreds of news organizations from across the globe to bring home the realities of a warming planet. Making a living from the ocean in southern California is never easy, but the planets changing climate is creating additional hurdles. KPBS reporter Eric Anderson has a look at a Carlsbad shellfish business that puts a premium on resiliency. Speaker 2: 00:28 Andrew Chang stands on a small floating pier in a San Diego Lagoon. We want to take a closer look. Chiang works at the Carlsbad Aqua farm. The small hatchery has been selling oysters and mussels to restaurants and other businesses for 50 years. Chang is standing on a Flexi. It's a floating system that pulls water and nutrients up through silos that are full of fledgling shellfish. Determined term would be seed oyster seed and they're anywhere from one to three centimeters. When these oysters get big enough, they'll be placed in square plastic trays stacked 10 high. Though stags are underwater in the Agua heading on to Laguna and Carlsbad production manager, Matt Stinky pulls about next to a barrel shaped buoy above one of those underwater stacks. Now these stacks of oysters are out a hundred to 150 pounds. Stinky says the oysters will live here filtering water until they're fully grown. The last doc is a few days of renting in a nearby building and then their pack for market. But this seed to lagoon to purification bins to market cycle was interrupted by a changing climate. In 2007. The planet's oceans were absorbing larger amounts of carbon, turning the colder waters of the Pacific northwest, increasingly acidic. Unfortunately for oyster growers, that's where all of their seed stock was grown, Speaker 3: 01:56 where an ocean acidification hit the Pacific northwest. Um, they were reporting a 90 to 95% failure in their normal production. And you ended up with a lot of farmers who had open space to grow things and they were unable to buy seed. Speaker 2: 02:10 The industry adapted and here in Carlsbad they now grow some of their own seed. But Stinky says the real threat isn't going away. Speaker 3: 02:18 That's possible that in 10 or 15 years, um, we start seeing more severe failures of, of crop possibly on our waters or in the rest of the industry. Speaker 2: 02:28 And the change is already happening. The ocean is warming as it absorbs carbon dioxide. Scripps Institution of Oceanography Researcher Dan K and says the warm ocean waters are less likely to mix with nutrient rich water at deeper levels. In essence, the warming water is choking off the food supply. Okay. And says that's not all the warmer the oceans get. Uh, the less oxygen it can, uh, accommodate and, uh, low oxygen is, is not good in general for ecosystems as the ocean draws in more carbon from the atmosphere k and says it's also changing the chemistry of the water. Over the last several decades, the acidity in the ocean has increased by about 30%. And um, that makes it more difficult for cal carious shelled and skeletal parts of the, the kind of baseline for the food chain to develop. Though the changes and their impacts will be gradual. Carlsbad aquafarms CEO Thomas Grim is already working to prepare. Speaker 2: 03:38 The alarm for me is that it's changing faster than some aspects of nature can keep up. Grim wants to keep his business from being overwhelmed by changes in the ocean ecosystem. Part of that solution is under the buoys that are just over his shoulder in the southern edge of the lagoon. Those are our research floats. There's both ball floats and barrel floats, but underneath them are families of oysters in different configurations. Some are very small groupings in specialized cages from Australia and they use to grow out selectively bred oysters from a research project at USC. Grim says oysters have survived other ecological upheavals and he says finding and breeding those resilient species is important. He says that changing ocean will change the business so you have to be ahead of what's going on and then have enough resilience stock that is adapted to these, to the changing chemistry. And while this business is fine now there is concerned about the future and that future is dealing with climate change. Eric Anderson, KPBS news, Speaker 4: 04:46 joining me with more on the impact of climate change. On the ocean is Andrew Dickson, a professor of marine chemistry at Scripps Institution of Oceanography and a leading expert on ocean acidification and Andrew, welcome to the program. Thank you very much. It's good to meet you. Now, what exactly is the impact of higher acidity on ocean species and I mean does it kill marine life? How does it change their environment? Essentially you're making the ocean a little bit more acidic and you're changing the composition of the ocean in the various will be referred to as carbonate species are changing their concentrations and different organisms respond differently to the various changes thus far with the changes that have occurred. It's not clear that it's killing organisms as you put it, but experiments in the lab show that at higher and higher levels, it clearly affects organisms in a variety of ways, some of which are obviously expected that shells for calcifying organisms grow more slowly or very poorly. Another interesting one. There was a discussion in Sweden where they grew shrimp and then they had a chef cook the shrimp and give it to pass us by in comparison with shrimp that had not been raised under acidic conditions and ask which one they preferred the taste, what did they say? And overwhelmingly if they preferred the not acidified conditions as improved taste. Speaker 1: 06:13 So there's something different going on. Okay. Speaker 4: 06:15 I think different than the organisms are growing differently, but we know this when we grow wines grow grapes for wine, it matters where the grapes were grown, what the conditions they're living under affects things like the taste. Speaker 1: 06:29 Now, recent research that you took part in found the west coast is almost like a bellwether for a changing ocean chemistry. Why are we facing these big changes? First, Speaker 4: 06:40 the picture that people have of what's changing is that as we're burning fossil fuels, that's coal and oil and natural gas. We're putting carbon dioxide into the atmosphere and quite a lot of this is ending up dissolving in the ocean and changing its composition. But that is happening gradually as we burn more and more along the west coast. There are a variety of other natural conditions. In addition to that, that essentially provide the same thing that more carbon dioxide is added to the ocean locally, either from upwelling of deep water along the coast. You know that it's often quite cold for swimming, and when that's happening, it's big as colder, deeper water is being mixed up into the surface region and there's more carbon dioxide in such water. In other places, it's more restricted areas where agricultural runoff has caused organisms to grow and decompose locally. Again, putting carbon dioxide into the water and these things together, added to the extra CO2 from the atmosphere means that the west coast kind of leads in how its effects are. The so-called bellwether. Speaker 1: 07:50 Yeah. You know, we're also seeing a, as you're mentioning here, lower oxygen levels in the ocean off our coast. How does that affect marine life? We've heard of these so called dead zones. Speaker 4: 08:00 Lower oxygen is exactly that, that there's a region where there's somewhat less oxygen, which means that all organisms that need oxygen for their metabolic processes find it harder. It's like if you go to altitude, if I'm go hiking in Colorado, I find it hard cause there's less oxygen in each breath I take, but I'm still alive and happy to go back to the hotel and have dinner afterwards. Then as that oxygen level gets lower and lower and lower organisms really start to have a problem. And there's a particular level at which you know a lot of marine organisms basically tried to flee the zone if they can or ultimately die because there's not enough oxygen and there's a variety of things that control the oxygen. One is as sea water warms up, less gas is able to dissolve in it and oxygen in the water is largely oxygen from the atmosphere dissolving in the surface ocean or maybe some oxygen produced in the surface ocean by phytoplankton growing and photosynthesizing producing oxygen. But the amount of oxygen that stays there is a little less when the water is warmer. And so we're getting less and less oxygen because of warm water. Speaker 1: 09:13 Is there anything that we can do to mitigate these changes in the ocean? Speaker 4: 09:18 I feel it's hard to come up with something that's an easy silver bullet. I mean there, there are a variety of things. One, you say, okay, I'm interested in the health of such and such a species. What can I do to do that? And you can say, okay, I can have areas where they're protected from everything else, like marine protected areas where there's no fishing there. And so it's a refugee for the species. Does that protect them against ocean certification? Not really, but if they're eating well and don't have other problems, it's not such a bad one. It's really the problem is not just ocean acidification but ocean acidification, increasing temperature, increasing fishing existing and over use and any other pollutions that are often in place close to shoreline. And so in many cases changing any one of these effects locally and help the Puget sound region particularly are looking to restrict the amount of fertilizer runoff from agriculture into the sound which they hope will cut down phytoplankton blooming in the sound and therefore this CO2 in the deep water which gets mixed up when they have a high wind, Speaker 1: 10:26 so there are pockets of Speaker 4: 10:28 rockets of sort of relief that you can actively do more generally you could say, well, don't burn anything ever again for energy, but that would significantly change everybody's way of life to the extent that although it's a, it's a good goal and areas of the world are moving far. Some areas are moving faster than others, that there's clear hesitancy because you don't fix it for yourself. You're fixing it for the world as a whole and if everybody else isn't playing the same game, you feel a little more concerned and tendency to be a little more selfish about it. Speaker 1: 11:05 I've been speaking with Andrew Dixon, he's a professor of marine chemistry at Scripps Institution of Oceanography. Thank you very much. Thank you very much. And you can follow the climate conversation at Hashtag covering climate now Speaker 5: 11:22 [inaudible].