Arthur T Knackerbracket has processed the following story:
In 2013, dozens of dolphins living in Florida’s Indian River Lagoon mysteriously began to die. Their remains washed up, showing the animals had been emaciated. Now, over a decade later, ecologists believe they’ve figured out the cause of the bizarre die-off.
While the deaths have long been linked to gigantic algae blooms in the water, it took until now to determine exactly how the two events were connected, and it turns out, it’s mostly humanity’s fault. This might be hard to believe, but apparently dumping massive amounts of human waste and fertilizer into waterways can be bad.
As the ecologists note in the journal Frontiers in Marine Science, the long-lasting phytoplankton blooms began in 2011. The spread of the tiny plant-like organisms led to a widespread change in the Indian River Lagoon’s ecology. Their presence caused the amount of seagrass in the water to decrease by over 50%, and a 75% loss of macroalgae (better known as seaweed).
That alone wouldn’t have killed off the dolphins, but when the ecologists examined isotopic ratios in teeth samples taken from the carcasses, and compared them to teeth taken from 44 dolphins that hadn’t been part of the die-off, they realized their diets had been drastically altered. The dolphins had eaten 14% to 20% fewer ladyfish, a key dolphin prey animal, but had eaten up to 25% more sea bream, a less nutritious fish. In essence, the presence of such large amounts of phytoplankton had reduced the amount of food available for the dolphins’ usual prey. As the prey numbers dwindled, the dolphins had to catch more prey to consume the same amount of energy. The effects weren’t felt just by those dolphins that died, but by the area’s dolphin population as a whole. At the time, 64% of observed dolphins were underweight, while 5% were classified as emaciated.
“In combination, the shift in diets and the widespread presence of malnourishment suggest that dolphins were struggling to catch enough prey of any type,” said Wendy Noke Durden, a research scientist at the Hubbs-SeaWorld Research Institute, who worked on the research, in a statement. “The loss of key structural habitats may have reduced overall foraging success by causing changes in the abundance and distribution of prey.”
The historic record bears this out. According to records kept of the recorded causes of death for stranded dolphins, starvation was the cause of death in 17% of recorded dolphin deaths in the area between 2000 and 2020. That number spiked to 61% in 2013.
“Blooms of phytoplankton are part of productive ecological systems,” said Charles Jacoby, strategic program director at the University of South Florida, who also worked on the study. “Detrimental effects arise when the quantities of nutrients entering a system fuel unusually intense, widespread, or long-lasting blooms. In most cases, people’s activities drive these excess loads. Managing our activities to keep nutrients at a safe level is key to preventing blooms that disrupt ecological systems.”
There is a small silver lining to this grisly finding. As the researchers noted, waste and other crap dumped into Indian River Lagoon is being gradually reduced and is expected to hit safe levels in 2035.
Journal Reference: https://doi.org/10.3389/fmars.2025.1531742
(Score: 4, Informative) by JoeMerchant on Thursday April 10, @06:50PM
Indian River Lagoon is mostly humanity's fault. We have played with the dolphin there (more than seven years ago, because - you know it's not legal to approach a wild dolphin, but when they're approaching you what are you gonna do?)
Anyway, there's a series of islands along the intracoastal waterway channel there, the islands were made by dredging the channel.
The inlets around there are heavily armored with rocks and concrete to prevent them from moving as they naturally would with currents, waves and especially hurricanes.
There are vast shallow flats that probably wouldn't exist without the dredged up causeways crossing the lagoon.
And, on top of all that, every dog and cat that shits in the yards of the waterfront properties, and there are a LOT of them, are putting their pet-waste into the runoff along with all the lawn pesticides, herbicides, fertilizer, etc. and basically nothing is being even acknowledged about this, though on the beach side you can occasionally see streaks of bright green sand running down from the over-fertilized lawns.
Anyway, one of the problems they do occasionally acknowledge is the dumping of raw sewage from the whole inland population into the bays, because that rises to a level that kills EVERYTHING in the water. I was in middle school in the late 70s when the first blades of turtle grass returned to Tampa Bay after a 50+ year absence due to uncontrolled sewage dumping. We _can_ do better, we _have_ done better even with population soaring 10x and more during the interim.
So, yeah, the marine life in the Indian River Lagoon somewhat resembles pigeons eating cigarette butts in urban downtown areas. But, the dolphin still play there, possibly because the fish are easier to catch there than they are out in the ocean.
Anyway, it's disappointing that our local pet dolphin are starving to death due to fluctuating food supplies in the semi-urban lagoon, but hardly surprising. When the manatees were starving to death in the St. John's river recently (due to unusual - for the past - weather patterns) activists went out to (illegally) feed them, and likely saved quite a few - nobody raised much of a fuss about them interfering with "nature" as coded in State Law.
🌻🌻🌻 [google.com]
(Score: 3, Insightful) by chucky on Thursday April 10, @08:48PM (3 children)
In other words: once you make something dirty, bad things will grow around it, good things will die. And this is what should be taught to the kids. No need to talk about global {current_popular_buzzword}. Just the basics.
(Score: 2) by Mojibake Tengu on Friday April 11, @03:09AM (2 children)
A fine good that is. Verily good enough. Reminds me of bears in Slovakia, current year.
Rust programming language offends both my Intelligence and my Spirit.
(Score: 2) by JoeMerchant on Friday April 11, @03:54PM
With all the dolphin in the wild, if they only get blamed for 2-3 human deaths per year (out of the 62 million human deaths in 2024), that's pretty remarkably low numbers.
Google AI is pretty brain-damaged when asked: "how many people die per year from falling coconuts" but it seems that number is around 150, and sharks weigh in around 10 human deaths per year.
Meanwhile, ~720,000 humans are thought to be killing themselves every year.
🌻🌻🌻 [google.com]
(Score: 3, Touché) by OrugTor on Friday April 11, @04:56PM
2-3 deaths a year is pitiful. Dolphins need to get their act together.