Wednesday, April 12, 2023

Some good news. Lake Tahoe’s best clarity in 40 years is the work of this ‘natural cleanup crew’

 Scientists attribute the ‘unprecedented’ visibility of the water body to a boom in the population of zooplankton.

Lake Tahoe has attained a clarity that scientists haven’t seen in 40 years – and it’s all because of a microscopic animal acting as a “natural cleanup crew” to restore the clear blue waters.

On Monday, researchers from the UC Davis Tahoe Environmental Research Center (TERC) released their annual report showing that the lake’s average visibility in 2022 was at 71.7ft – compared with 61ft in 2021 – which was largely due to a spike in clarity in the last five months of the year.

Such a sudden improvement “is, I believe, totally unprecedented”, said Geoffrey Schladow, TERC director, to the San Francisco Chronicle. “We’ve never plotted data like this, where the last five months of the year were totally different” from the remainder of the calendar year.

The dramatic change can be attributed to an uptick in the concentration of zooplankton, tiny critters that are specialized to consume particles that inhibit the lake’s visibility and an unexpected depletion in the numbers of Mysis shrimp that normally would eat those zooplankton. According to Schladow, the zooplankton, especially the Daphnia and Bosmina species, “largely disappeared from the lake after they were grazed down following the introduction of the Mysis shrimp in the 1960s”.

Other factors can affect changes in lake clarity including winter runoff, the warming of the lake’s surface and the concentration of particles such as silt, algae or clay. But TERC’s research says the primary factor in the lake’s recent clarity sits squarely with the Daphnia and Bosmina zooplankton.

8 comments:

  1. Geoffrey Schladow gets paid a quarter of a million dollars a year to putt around Lake Tahoe on a very nice boat and drop a disk into the water to measure clarity.

    And you thought you had a good job.

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  2. No 2-cycle engines are allowed on Tahoe, which helps a lot, less oil discharge.

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  3. There is a fine line between being a good steward and worshipping the creation instead of the Creator.

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  4. In the Great Lakes, "ecologists" are complaining that the water is being made too clear, thus damaging life forms which rely on murky water. You cannot please these religious zealots.

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  5. Fredo’s body finally completely dissolved.

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  6. Begs the question...what happened to the shrimp.

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  7. So excess water runoff cleared the lake (ie Mother Nature) and the Wizards of Smart tells us...Zooplankton? Sure, of course....Sod off Swampy!

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  8. Lake Tahoe.
    No ice fishing allowed.
    Ha!

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