More than 100 dolphins dead in Amazon as water hits 102 degrees Fahrenheit
Source: CNN
More than a hundred dolphins have been found dead in the Brazilian Amazon amid an historic drought and record-high water temperatures that in places have exceeded 102 degrees Fahrenheit.
The dead dolphins were all found in Lake Tefé over the past seven days, according to the Mamirauá Institute, a research facility funded by the Brazilian Ministry of Science.
The institute said such a high number of deaths was unusual and suggested record-high lake temperatures and an historic drought in the Amazon may have been the cause.
The news is likely to add to the concerns of climate scientists over the effects human activity and extreme droughts are having on the region.
Read more: https://www.cnn.com/2023/10/01/americas/amazon-river-dolphins-dead-temperatures-drought-intl-hnk/index.html
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a Botulism strain by eating dead and/or fermented fish carcasses after/during a high-water-temperature water kill.
River dolphins have a thermoregulatory mechanism that adapts to a temporary high temperature aquatic envirnoment, is it possible that hungry mammals and a strain of botulism might also have also played a part or had a simultaneous effect in the wild. The OP article only reports the dolphins died en masse. The following study tested the dolphins mechanism to prevent heat stroke. In this researched mechanism, dolphins ability to survive high-aquatic temps is short-lived and can only occur once, not swing back and forth, if no other environmental changes for the better occur or indeed proceed past maximum heat transfer. The mechanism involves a well-nourished fat layer and blood vasculature to guard against core heat organ build-ups of heat.
In addition, eating large amounts of dead fish infected with colonized botulism spores may not have been considered in the OP article. Botulism strains may have shed and spread disease by re-activation to produce toxins at high temps in stagnant aneorobic conditions. Bolulism strains in the aquatic envirnment that cause disease are fairly hard to detect and are usually diagnosed based upon symptoms that can develop rapidly or may be dependent on amount of shedding and/or consumption. Either way, it causes neurological damage that can improve but never be cured entirely once damage occurs. This may have caused neurologic problems in the dolphins that might have weakened and paralyzed skeletal muscles including those for respiration and movement and/or digestive mechanisms that fail and are readily spread in a "schooled" natural follow the leader situation or when voice communication(s) became paralyzed and interpreted erroneously.
When is a hot-water environment too hot for too long??? Actual temps experienced in the wild may have exceeded tested mechanism maximums for the study???
https://journals.physiology.org/doi/pdf/10.1152/ajpregu.1999.276.4.r1188
Pride, I think, is our greatest sin. I used to think it was greed, & that's a big problem, too, but pride in our big brains, thinking we control everything, that we're not like other animals who over populate & over consume, that we can make everything right if we screw up cuz we're so smart. Mother Nature is about to knock us down a few pegs. Too bad we're taking so much good with us.
