Dissolving Dungeness?

By Jim Steele,

Published in Pacifica Tribune March 8, 2020

What’s Natural

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Like New England’s lobsters, savory Dungeness crabs are San Francisco and the northwest’s iconic seafood. While fisheries around the world have declined from overexploitation, Dungeness crabs have been sustainable despite intensive harvesting over the past 40 years. Their resilience partly relies on mature females producing 1 to 2 million eggs each year. Thus, harvesting females commercially is illegal.

Unfortunately, few eggs survive to adulthood. Besides being preyed upon, early life stages (larvae) must survive being swept out to the open ocean and then return a few months later to shallow near-shore waters. The more larvae that survive that trip, the greater their abundance. But if the winds and currents prevent the larvae’s return, populations could crash as they did in the 1950s.

The successful return of Dungeness larvae largely depends on the strength and timing of upwelling currents. When eggs hatch, larvae rise to the surface and are then blown offshore. If larvae float into the California Current, they’re carried southward and further offshore. But below the California Current is the Undercurrent, transporting warmer waters northward. Northward currents also strengthen during winter. By migrating daily between contrasting surface and deeper waters, larvae minimize being swept too far away. Then beginning around April, a strengthening California Current creates upwelling currents that carry larvae back towards the coast while larvae remaining in the open ocean die.

Upwelling currents also promote plankton blooms by bringing essential nutrients back into sunlit surface waters. Upwelling enables the entire marine food web to flourish. Larvae that settle in regions bathed by upwelling water, benefit from 10 times more food than elsewhere. Upwelling also increases the abundance of sardines and anchovies, but that causes a problem for crab fishermen.

Humpback whales feeding on anchovies are attracted to Dungeness fishing grounds. Recovering from past exploitation, larger whale populations are more likely to encounter crab trap buoy lines and deadly whale entanglements increased. So commercial crab fishermen agreed to further restrict fishing season to minimize overlap with feeding whales. Promising technological solutions to eliminate buoy lines are a work in progress.

In 2015, beneficial upwelling also enabled a bloom in plankton species producing domoic acid. Passing up the food chain, high doses of domoic acid cause neurological damage to birds and mammals. Detecting high domoic acid levels in crabs, public health agencies shut down the 2015 Dungeness season until the danger passed. That was economically devastating for fishermen. Hoping to recoup their losses the Pacific Coast Federation of Fishermen’s Associations blamed climate change and sued 30 oil companies. But they are unlikely to win their lawsuit.

Outbreaks of domoic acid poisoning correlate with upwelling and natural ocean oscillations. The northward currents can bring additional domoic-acid-producing species into Dungeness habitat. Then with seasonal upwelling, their numbers explode. In 1961, a similar plankton bloom disoriented seabirds. Monterrey newspapers reported birds flying into buildings and people, inspiring Alfred Hitchcock to produce his iconic horror film “The Birds”.

Unfortunately, bad science also promotes media horror stories such as CNN’s headlines, “The Pacific Ocean is so Acidic that it’s Dissolving Dungeness.” But in truth, ocean pH is far above 7.0; oceans are alkaline, not acidic.

Still NOAA’s West Coast Ocean Acidification program seeks worrisome examples of “acidification” and it was their researchers who prompted those horrific headlines. They found Dungeness larvae in off-shore waters (with a slightly higher pH) had smoother inner shells, versus larvae in near-shore waters (with a slightly lower pH) that had shells with patchy dissolution. The dissolution was invisible to the eye. Researchers had to remove the shells’ outer protective layer and examine the inner shell with scanning electron microscopes and various x-ray technologies to find microscopic “changes”. And despite a correlation with lower pH, the measured pH should not have caused any dissolution.

Dungeness larvae reaching near-shore waters are transported by the naturally low-pH upwelling currents. That upwelled water is derived from the Undercurrent, which is fed by waters originating in the deep Pacific Ocean. Those deep waters had not been exposed to our atmosphere for hundreds to thousands of years. Suggesting low-pH upwelled waters are worsened by “atmospheric carbon dioxide” was a false narrative. The lower pH and high nutrients are produced by hundreds of years of decaying organic matter.

When Dungeness larvae return to near-shore waters, they settle to the ocean floor and soon molt into their first juvenile shells. Larvae absorb minerals from their old shell to recycle into their new shell. That causes patches of dissolution. The researchers’ data from one near-shore location was discarded because pre-molt dissolution had clearly started as expected. Still and oddly, researchers blamed that observed pre-molt, but slightly less dissolution, on “ocean acidification” prompting endless media horror stories. What is never told is Dungeness larvae remaining offshore do not molt into juveniles, so would not be undergoing pre-molt dissolution. And despite their smoother shells, larvae remaining in offshore waters die.

Misleading science from researchers who are blinkered by their advocacy for an “ocean acidification crisis” is problematic. We need objective science, not “dissolving Dungeness” fear mongering.

Jim Steele is director emeritus of the Sierra Nevada Field Campus, SFSU and authored Landscapes and Cycles: An Environmentalist’s Journey to Climate Skepticism.

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27 thoughts on “Dissolving Dungeness?

  1. “The Pacific Ocean is so Acidic that it’s Dissolving Dungeness.” is a typical misleading, distorted and even lying headline that Alarmist Media likes to use in order to sell its dubious services. The Ocean is consistently alkaline. Over short periods it is less and more and again less alkaline but it is never acidic. CNN is one of the worst offenders in this field of pseudoscience. All of Climate Alarism and Warmist Hysteria is based on these sort of lies.

  2. “Still NOAA’s West Coast Ocean Acidification program seeks worrisome examples of “acidification” and it was their researchers who prompted those horrific headlines. They found Dungeness larvae in off-shore waters (with a slightly higher pH) had smoother inner shells, versus larvae in near-shore waters (with a slightly lower pH) that had shells with patchy dissolution. The dissolution was invisible to the eye. Researchers had to remove the shells’ outer protective layer and examine the inner shell with scanning electron microscopes and various x-ray technologies to find microscopic “changes”. And despite a correlation with lower pH, the measured pH should not have caused any dissolution.”

    The love affair of climate science with the ocean acidification thing against all the odds in the data is one of the most bizarre twists of the climate change story. Here is one of my ocean acidification posts.

    https://tambonthongchai.com/2019/12/14/ocean-acidification-2019/

  3. Jim,
    You da man! I learn so much from you. Thank you and I hope you keep it up for a long time to come.

    • Yes, Jim is one of the most professional and informed posters her. I always dive straight in.

      Without Jim’s article I would not have know than climate change is now cause demonic acidification in the Pacific 😉

  4. My first post on “dissolving” Dungeness crabs was on January 31st, 2020, “The Solution To Dissolution“.

    My second post published on February 2nd, entitled “Dungeness Crabs Redux“.

    It’s an important issue, so I’m glad to see Jim discussing it as well. And because I respect Jim’s opinion, I’m also glad to see that he agrees with my previous posts.

    Best to all, particularly the crabbies,

    w.

  5. I hear there are places in the ocean that have turned to crazy glue so the crabs all stick in place, especially the ones that have joined XR groups.

    And, don’t call me ‘Davida”..

  6. Earlier, I wrote:

    I hear there are places in the ocean that have turned to crazy glue so the crabs all stick in place, especially the ones that have joined XR groups.

    And, don’t call me ‘Davida”..

    –oops, that was a play on Bob Tisdale’s “Don’t Call Me Shirley” gag over on the Mt. Rainier thread —

  7. Makes you wonder how a population dependent on so many variables completely outside its control has survived this long. Could it possibly be that biological systems have rather more resilience than some people would have us believe?

  8. UK lobster fisheries have been improved in recent years by the harvesting of egg carrying females, so that their eggs can be brought on to a later stage in development before returning to the sea.

    • Oh no, we can’t do that. It was done to salmon and steelhead and now they are considered Franken Fish by environmentalist. You should hear them twist the facts. “Fish counts have cratered we need to shut down the fishery!” In reality native returns are low but we might be having a record return of hatchery fish but that doesn’t matter. The one and only count that matters is native fish because that’s the count they use to push their agendas.

  9. Thank you, again, Jim Steele.
    You always state the science clearly with context and facts that frame or correct misleading or incomplete research publicity.
    Willis, thanks for your comment and previous articles….no need to “upstage”.
    Your two approaches are usually quite different.
    Willis seems mostly statistical in method on wide-ranging data sets, while Jim uses known biological / chemical / environmental processes.
    Both methods are needed and helpful to understand, reinforce or differentiate findings and conclusions.
    That is science!

  10. Yet again, incompetence through impatience. People believe advertising exists to educate them.

  11. Why hasn’t the Ocean Acidification myth been buried yet? Anyone who understands buffering (1st-year Chemistry) can write an acid-base equilibrium expression and actually approximately calculate the change of pH with change of pCO2, which is tiny.

    • As to burial, I just ran across this–https://tos.org/oceanography/issue/volume-28-issue-02
      Volume 28 (2) June 2015,Special Issue: Emerging Themes in Ocean Acidification Science, last paper is Overturning Assumptions: Past, Present, and Future Concerns about the Ocean’s Circulation, pp. 240-251. by M. Susan Lozier , Earth and Ocean Sciences Division, Nicholas School of the Environment, Duke University, Durham, NC, USA, and also President of The Oceanography Society. The 16th of the Roger Revelle Commemorative Lecture Series.

      Brief check did not note any “acid” clarification, but from Abstract of article on California Current–“Subsequently, researchers at Whiskey Creek Shellfish Hatchery, working with academic and government scientists, showed a high correlation between aragonite saturation state (Ωarag) of inflowing seawater and survival of larval groups, clearly linking increased CO2 to hatchery failures.” and from one on Characterizing the Natural System… “Ocean acidification is a global threat to these ecosystem services,”

      Maybe Lozier’s article has been analyzed before, but a brief examination makes one wonder about it, conclusions based heavily on modeling studies, and selective information like the distribution of tritium after nuclear tests. That the conveyor belt is sloppy seems reasonable, but the paper itself concludes –“What we don’t understand, however, are the mechanisms that control overturning strength and how and why the overturning will change in the decades ahead.”

      I used to be a member of the Oceanography Society, has lots of good information, apparently now like many ‘scientific’ societies. Somewhere in their holdings there ought to be clarification about what we all know is not, as actually promoted, simplistically acidification in distilled water, but not for an ocean full of sodium, calcium, dead and alive organic matter. But that is apparently “Old Oceanography.”

      • Whiskey Creek Shellfish Hatchery story is old and has been analyzed many times over. Native oysters were overfished so the industry imported Japanese oysters. To maximize success hatcheries were started. There is a small window of time a day or sos, during which the larvae shells are not fully formed and larvae are vulnerable to low pH extremes. Water from the tanks are pumped from the estuary where the larvae will get re-introduced. The hatchery unwittingly had pumped water from the estuary in the morning and coinciding with an upwelling event. Morning water has the lowest pH of the day, which was the exacerbated by low pH upwelling. The hatcheries now monitor for upwelling events before pumping the water into the hatchery tanks and since have hd not problems. Nonetheless the brief problem was told by alarmists as a acidification catastrophe which Gove Inslee capitalized on to get grants

  12. Just curious – What is the actual pH range of the Dungeness waters we’re talking about, and what is the projected range from carbonic acid acidification? Carbonic acid is a very weak acid. Does the projected range in fact damage shell formation of the Dungeness? So many unanswered questions.

    Thanks!

    • Most shells of all organisms have a protective organic layer that insulates them from direct affects of changing ocean pH.

      When the larvae are off shore, they migrate daily from the surface which is typically around 8.1, down to 60 meters or more. The researchers reported the offshore pH at 60 meters depth varied from 7.79 to 7.87.

      The nearshore waters varied t 60 meters depth from 7.48 to 7.85.

      The hype about ocean “acidification” usually focuses on the surface water. Many scientists avoid measurements from coastal waters because pH varies greatly due to upwelling and inputs from rivers and streams. The surface pH prediction for 1000 ppm atmospheric CO2 is about 7.8 . But that is a ph that all vertically migrating marine organisms experience everyday at 60 meters depth

  13. “Unfortunately, few eggs survive to adulthood. Besides being preyed upon, early life stages (larvae) must survive being swept out to the open ocean and then return a few months later to shallow near-shore waters.”

    Also known as whale food for anchovies and certain types of whales.

  14. When the California fishermen association decided not fish, and encouraged others not to fish when it was safe to do so, it became apparent that they were in it for the lawsuit monies rather than any other reason.

    It was a game for them, partnering with the sleazy environ lawyers, and making them just as sleazy.

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