Lake San Antonio in Monterey County , California , has been closed to the populace amid investigations into the huge numbers game of dead fish washing up on the lake ’s shores over the course of study of several days .

Monterey County functionary first announced a “ large fish death event ” in a July 6social medium post , take down that the California Department of Fish and Wildlife had been advise . At that clip , the cause of death was believe to be the result of “ extreme temperature modification , causing oxygen depletion in the water ” with California late having been hit by a disc - breakingheatwave .

The lake remained subject , with officials stating they did not believe there was any risk to man or their PET , but visitors were cautioned to leave behind the numb fish alone .

But on July 10 , Lake San Antonio was squeeze to close to visitant .

“ The fish die off we alerted you to last Friday has get bad , ” said county officials in aFacebook post , “ and the lake is being close as a public health caution while examination and clean up is being done . ”

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Fish ranging in size of it from small baitfish through to larger catfish , bass , andtroutcould be seen swim in the lake ’s water system and lave ashore , attracting scavenge birds and maggots . “ It seems like every Pisces the Fishes species in the lake is being impacted , ” Chief of Parks Bryan Flores toldSFGATE . “ We have never seen this type of multi - species die - off , peculiarly on this scale . ”

While previously suspect as having something to do with the sweltering temperature , the cause of the people die - off is now being treated as strange until investigation provide further information .

“ We ’re waiting on reports back from the Department of Fish and Wildlife , Water Resources Agency , and Health Department to see what the cause of this massive fish die - off is , ” said Flores in a video posted toFacebook .

But the official does have some estimation of what may or may not be behind the upshot , which he believes could have been ad-lib and unlikely to have a more villainous root .

“ If it was a poison , you ’d think it would be affect the other species , ” Flores explain toKRON4 . “ More than likely , it is some kind of biological unconscious process that ’s come about , whether or not it ’s alga or phylum Protozoa . ”

Until that possibility is or is n’t confirmed , however , thelakeremains closed indefinitely .

In a statement seen by theSan Francisco Chronicle , Flores say : “ While this may be a raw occurrence , until it is sleep with that this is not being because of a biological transmitter or pollutant that could cause scathe to the populace , we must keep the public good by exit the parkland . ”