One of the most despairing fates is to be trapped in a vortex of death, much like ants!
Round and round, ceaselessly spinning, without eating or drinking, oblivious to whatever may be happening around them, as if possessed, only circling until finally exhausted and perishing.
Recently, similar incidents have occurred in various animals in the United States, involving at least 44 species of marine creatures exhibiting a bizarre phenomenon known as "death spirals," culminating in mysterious deaths. Scientists have yet to determine the cause!
The earliest discovery was made by diver Gregg Furstenwerth in November 2023, when he encountered an unusual fish while exploring the seabed of the Florida Keys:
It was swimming upside down, continuously spinning in circles, sometimes clockwise, then counterclockwise.
Finding it amusing, Furstenwerth captured the sight with his camera.
As he conversed with other divers, he noticed a growing number of similar spinning incidents, realizing it might be a collective behavior, prompting him to meticulously document these rotational behaviors among marine creatures.
The phenomenon extended its influence over a wide range of species, including:
needlefish, sardines, sand perch, grouper, rays, and sharks, among others, even including the critically endangered smalltooth sawfish. Recently, he also observed a spinning octopus.
There seems to be a spreading pattern in the locations where these occurrences take place.
As of March 24, 2024, there have been hundreds of sightings in total.
Initially, the phenomenon of animals spinning in circles was mainly concentrated along the 35-mile stretch of coastline in the Lower Keys (part of the Florida Keys), but sightings have also been reported in areas such as Miami.
At least 44 species have been involved, with specific death tolls unknown.
The most severely affected species is the critically endangered smalltooth sawfish, with 109 individuals observed exhibiting spinning behavior. At least 28 of them have been confirmed dead, most of which were larger individuals ranging from 2.1 to 4.3 meters in length.
Unlike the spiraling death marches of ants, where exhaustion leads to demise, these marine creatures exhibit abnormal behavior post-spinning, often beaching themselves and perishing, some already deceased before reaching the shore.
The culprit behind the death spiral?
During research, scientists observed that these fish exhibited peculiar behavior while spinning in circles, often popping their heads above the water surface, alternating between floating upwards and sinking downwards. This erratic movement gave the impression of disorientation and balance issues.
Hence, it is speculated that these animals may be unable to maintain balance, resulting in flipping upside down and sideways swimming, ultimately leading to spinning in circles.
In response to these symptoms, researchers have listed a plethora of potential causes, including toxic algal blooms, diseases, parasites, environmental factors such as low oxygen or high temperatures, and marine pollutants...
Scientists state, "Identifying the cause is a challenging task, but to mitigate animal mortality losses, we must race against time. Especially for the smalltooth sawfish, which is already an endangered species. The death of a dozen or so smalltooth sawfish could potentially impact the species' development and recovery. With nearly 30 casualties already, the situation is extremely urgent!"
First, scientists conducted autopsies on the deceased individuals to rule out the possibility of infectious diseases.
Second, environmental factors such as algal blooms, oxygen depletion, temperature, and pH levels were also ruled out.
While certain algae can proliferate massively along coastlines and produce toxins, no evidence of algal blooms was found in the waters where the circling animals were discovered, and no toxins were detected in the water.
Furthermore, factors like low oxygen levels, high temperatures, and parasites were also deemed unlikely causes.
As a result, scientists turned their investigation towards the depths of the ocean.
The prime suspect at the moment is a single-celled algae known as Gambierdiscus, which typically inhabits the seabed.
Scientists collected water samples from the areas where the circling fish were found and conducted tests, revealing significantly higher levels of Gambierdiscus algae compared to normal seawater—approximately 1000 cells per liter as opposed to the usual 30-40 cells per liter in unaffected areas.
This type of algae contains saxitoxin. Generally, it's harmless when fish and marine organisms ingest this toxin, but humans are more sensitive to it.
When coral fish consume this algae, saxitoxin, as an acquired toxin, enters their bodies and then moves up the food chain, accumulating in predators.
The distribution of the toxin in fish is uneven, with the highest levels found in the liver and the lowest in the muscles and bones.
Saxitoxin is a neurotoxin, reportedly 100 times more toxic than pufferfish toxin. It's resistant to high temperatures and cannot be removed even through cooking. Stomach acid also struggles to break it down.
Once humans consume fish containing the toxin, symptoms range from nausea and vomiting to mild motor paralysis. In severe cases, individuals may be unable to stand or maintain balance, and respiratory muscle paralysis can lead to suffocation and death.
Currently, animals showing neurological symptoms such as hyperactivity, inability to maintain balance, and disorientation when sick or dying could be exhibiting signs of saxitoxin poisoning.
To verify this hypothesis, scientists are facing considerable challenges. Saxitoxin is colorless, odorless, and visually undetectable, and there is currently no rapid, effective, standardized method for detection. Directly testing for this toxin through autopsies is difficult. Even if detected, the presence of the toxin in the fish itself complicates interpretation.
Subsequently, scientists opted to collect seawater from areas experiencing disease outbreaks and then rear healthy fish in it to observe if they display circling behavior. This method aims to examine the relationship between algae and circling behavior in marine life.
As of now, no conclusive results have been obtained.
In the end, what concerns Americans most is still the smalltooth sawfish. Scientists believe that the impact on smalltooth sawfish is far more severe than imagined, with a risk of extinction.
After the death of smalltooth sawfish, there is a high probability that the bodies will sink, making it difficult to accurately estimate the true number of deaths.
Currently, several institutions in the United States have jointly launched the first rescue operation for smalltooth sawfish. Wild smalltooth sawfish encountered will be temporarily placed in artificial facilities until the cause of the disease is identified.
