Wednesday, October 7, 2020

SearchResearch Challenge (10/7/20): How are the kelp forests doing?


One of the glories of plant life on planet Earth are the great kelp forests along the coasts... 

Photo by Dan, taken in a kelp forest near Santa Rosa island.

Near me, along the coast of California, is an 800 mile long coast that has historically been an almost continuous kelp forest.  Kelp has historically run from Baja Mexico up to Alaska.  (This kelp is all members of the Laminariales family; I don't mean "seaweed" in general, as the term kelp is sometimes used.)  

The coast of California used to look much like this. The dark areas in the water are stands of kelp. 
Was this forest near Gualala, CA larger in the past?  How would you know?  

I grew up snorkeling and diving the Los Angeles area coastline, and as I recall, the kelp forest was luxurious, dense, and grew fairly close to shore.  

It can be intimidating to swim through, but if you've been in heavy kelp enough, you quickly learn to control your panic when it seems to wrap tightly around your ankles.  It's pretty slippery stuff, so as long as you don't make any quick movements, but if you slowly and carefully untangle yourself, it's not bad.  

Well, there was that one dive off Santa Rosa island where my feet got pretty tangled up with only 500 psi left in my tank... at 45 feet deep.  That's a moment that'll decalcify your spinal column.  But a bit of slow breathing and carefully reaching down and unwrapping my ankles got me free.  Move slowly and carefully, don't panic.  It was maybe only twenty seconds, but felt like twenty minutes. 


As I travel up and down California these days, I can't help but notice the kelp beds that line the coast.  I've read a few articles about the changes in kelp that have been happening over the past 30 years, but I wonder--what's really going on?  Is it truly getting better?  Or are things getting worse? 

That curious question leads to today's Challenge: 

1. How are the California kelp forests going these days?  Are they healthy? 

2. Can you find some data about the state of the kelp forests?  How can one measure the forest and create a data set to analyze kelp forest health over a span of decades?  Can you find such a multiyear data set?  

What say you?  Can you find this information?  

As always, be sure to let us know HOW you found it.  Did you use a special resource?  Did you use a particular set of search terms?  Enquiring minds want to know!  

Search on! 


  1. Replies
    1. This is great, Remmij! Do you remember your search path to find this content?

    2. rough re-capture - seemed Luna was cited somewhere as leading a research group looking at kelp forests… used serps and images to glean leads…
      as I recall, used your description of your dive and came up with this:
      Well, there was that one dive…
      Rodrigo Beas Luna
      Cooperative research
      kelp data base, etc.

  2. Replies
    1. Fascinating stuff. His paper on "The Smallest Great White Shark" is fabulous.

  3. ⌘-f
    Santa Rosa
    Channel I.

    "Diving in a kelp forest is a three-dimensional wilderness experience. It has been likened to hiking through a redwood forest, sans gravity. Imagine yourself hovering in the middle of the water column. Kelp rises above you to the surface where it spreads out in a thick canopy. The fronds are held afloat by gas-filled bladders. The sun's rays penetrate in shafts through crystal-blue water playing off fronds flowing gracefully in the current. Below are boulders covered with life on top of life, competing for space."

  4. I started with "500 psi left in my tank... at 45 feet deep." As I don't know anything about scuba diving

    [500 psi how much time of oxygen gives] at 6 liter per min= 28 minutes. How many liters are needed, Dr. Russell? How that is established?

    [How fast can you ascend scuba diving]
    A. 30 feet per minute

    [California kelp forest status 2020]

    [Kelp forest status after:2019]

    Many good results. In tablet my results give more answers. In laptop, more links

    California’s critical kelp forests are disappearing in a warming world. Can they be saved?
    The “sequoias of the sea” suck up carbon and shelter special species. They’ve been hit hard, but scientists, surfers, and more are banding together to save them.

    Lots of interesting things: Photos, links, and more. Says a multidisciplinary group to work. Also says eat them and the return of the abalone.

    Still need to read the links mentioned in this article.

    [Define abalone] Abulón in Spanish

    [California kelp forest health through the years] later I am adding after:2019 to my query

    Among the results, is this one in PDF: Current status and future trends in kelp forest ecosystems (Researchgate)

    "...Kelp forests grow predominantly along the Eastern Pacific Coast, from Alaska and Canada to the waters of Baja, California." NOAA Fisheries

    California has lost 90% of its kelp forests in the last 10 years. Caused by the proliferation of purple sea urchins, as their predators disappear from human impacts and climate change. (2020)

    [California "kelp forest" Snopes]

    Also trying with [California "kelp forest" data 2000.."2020"] My question is this query good? I added the "" to say to Google I want 2020 in the results.

    Landsat data maybe a keyword to search

    2020: The kelps are alright: Studies reveal resilience in kelp forests There Ctrl-F "California"

    And says: "In 2019, the California Department of Fish and Wildlife reported that kelp forests off the state’s coast had declined by 93% over a five-year period after a marine heatwave in 2014 appeared to have increased the numbers of purple sea urchins, an animal that grazes on kelp...The Landsat data also revealed that the massive kelp loss observed in California over the past five years was not seen in neighboring Oregon..."..."We really don’t understand kelp very well,” Sara Hamilton, a marine biologist pursuing her Ph.D. at Oregon State University..."

    [ Nereocystis]


    With [today i found out Forest kelp]

    What is a Kelp Forest? NOAA

    [Kelp forest in Mexico after:2018]

    Visited in cache " From Mexico to Alaska: Cooperative Research Effort by Oceansolutions.stanford. But my lap didn't allow me to visit

    1. Great finds, Ramón!

      I should have been a bit clearer in my "500 psi" comment.

      "500 psi" is the amount you should have left when you come out of the water. That is, I was already into the red zone, and I didn't want to be stuck in kelp, waiting for someone to return and help me get unstuck. As you can imagine, it would be easy to swim right by someone on the other side of a curtain of kelp and never see them. My buddy had just disappeared into the distance. Even if she had turned around, it would have been easy to not see me. In any case, "500 psi" left is getting into dangerous territory. Obviously, I was able to get unstuck, but it was kind of a close thing.

    2. Thanks, Dr. Russell.

      Yes, I thought so for what you said about the Spinal Column. Just that I searched in general about how much is PSI and how fast someone can surface. Thanks for adding that important data you mention. I didn't search for that nor how much PSI has a full tank. I'll search

    3. I kept searching about Oxygen and Scuba Diving. As I mentioned, I don't know anything so reading Dr. Russell's story was very interesting and also made me think in stuff that never thought about. Not even when saw people taking Scuba classes or when Dr. Russell have posted about his travels.

      Dr. Russell, liters per minute is a fixed amount or it changes according to where you diving? Those 6 liters per minute is good amount?

      Searched [How much oxygen Scuba diving tank has]

      How much oxygen does an average scuba diver need?
      Predrag Maksimovich's answer sounds interesting and complete. He mentions thanks go from 7 liters to about 24. Also mentions the minimum of 6 liters per minute. And mentions this: "In general, it’s always much safer and much better, to have lots of air at the beginning and quite a lot of air when starting for the surface, to cover for the mandatory 3 min at 3 meters." That rule is real? What it means?

      [scuba diving 3 minutes rule]

      Always perform your 3-minute safety stop at 15 feet

      For the SRS Challenge, searched [ Kelp forest site:aaaa after:2019] aaa meaning for example:, and

      With these, found interesting results. One is Kelp found off Scotland dates back 16,000 years ago. Other, Sir Attenborough's plea to save 'magical' kelp forests.

      And specially this one:

      Bringing Back Sea Otters Benefits People, Too. Study was in Vancouver Island applicable to others

      And today found:

      Cayne Layton dives into his work on restoring kelp forests in cold-water oceans.

      Related to previous Challenges

      Two metres or one: what is the evidence for physical distancing in covid-19?

    4. A Search question out of topic, Dr. Russell.

      A friend asked me if it's possible to use Google Lens on videos. I said no, at least at the moment. Is that the right answer?

      I'll love to use Google Lens in the future not just in videos, also in YouTube videos and more. As I love how Google Lens is now in the Search bar in Google Assistant. And now thinking about it, Dr. Russell, do you know why Google Assistant didn't get a female name as other assistants?

    5. I was re-visiting SearchReSearch and noticed that The Joy of Search first anniversary was a few days ago.

      September 19, 2019. The Joy of Search ��

      And, SearchReSearch is almost 11 years old! That is impressive and amazing. Congratulations and thanks, Dr. Russell!

      January 30,2010. The First Post

  5. fwiw… also enjoys a good kelp patch… have you had an encounter?
    see trailer

  6. in space… and back again (2023) - asteroid landing (next week)
    101955 Bennu

  7. 1. CA kelp forests: I first looked to using the imaginative term [kelp] which had many hits but the best is 'California's crashing kelp forest How disease, warming waters, and ravenous sea urchins combined to kill the kelp and close the red abalone fishery.' Sep 2019.

    "In a study published today in the journal Scientific Reports, scientists from the University of California, Davis, and the California Department of Fish and Wildlife use two decades of kelp ecosystem monitoring data to chronicle the catastrophic shift in 2014 from a robust bull kelp forest to a barren of purple sea urchins. Similar impacts are being observed in kelp forests from Baja California to Alaska." Rep[utable sources I think.

    In short: AZ perfect storm:
    2013: Sea star wasting disease killed mass numbers of sea stars, a purple sea urchin predator.
    2014-2017: A marine heatwave and El Nino event warmed the nearshore ocean.
    2015: Purple sea urchin populations exploded.
    2017: Mass mortalities of red abalone led to that fishery's closure in 2018 to the present.

    "What we're seeing now are millions and millions of purple sea urchins, and they're eating absolutely everything," said Rogers-Bennett. "They can eat through all the anemones, the sponge, all the kelp, the fleshy red algae. They're even eating through calcified alga and sand."

    "More than 90 percent of bull kelp and 96 percent of red abalone were lost along 217 miles of northern California coastline within just a few years. Meanwhile, purple sea urchin populations exploded 60-fold between 2014 and 2015.

    "We're in the 20th year of this monitoring program, and we can confidently say, this is uncharted territory that we're in," said lead author Laura Rogers-Bennett, an environmental scientist"

  8. I'll try this again - off topic, but related to prior sRs… off planet, but returning this time?
    101955 Bennu