https://lowvelder.co.za/518884/hippos-m ... ot-solved/?
Hippos’ mystery death still not solved
Ike Phaahla, GM of communications at KNP, emphasised that SANParks regards the situation seriously and investigations will continue.
49 mins ago
The mystery surrounding the unexpected death of 10 hippos and schools of fish in the Crocodile River in the Kruger National Park (KNP), has still not been solved.
This follows after the pod of dead hippos were discovered by a Malalane section ranger earlier this month. Along with the hippos, there were also scores of dead fish in the water close to Leopard Creek.
Shortly after, veterinarians and scientists were flown to the site to investigate and compile necropsy reports. Water samples and samples from the dead fish were taken. Blood samples from the dead hippos were also drawn.
Phaahla confirmed that nothing out of the ordinary was found in the tissue samples.
“The investigations are ongoing, and the next step is to test the bushes in that area.”
Readers have been speculating on social media platforms as the cause of death, with some claiming that it could have been lightning that killed the animals, while others wondered if the hippos could have drowned after the heavy rainfall that occurred at that time.
A few years ago, state veterinarians managed to confirm the cause of death of a number of animals that occurred in the Crocodile Bridge section of the park. These included at least 52 animals, including lions, cheetahs and seven white rhinos.
Inspection of the dams at the time revealed green scum on the surface of the water, and further tests confirmed that blue-green algae – known as Microcystis – was the main reason for the discoloured water.
One of the oldest known organisms on earth, blue-green algae, or cyanobacteria, were the first green plants on earth and are found in most water bodies in low numbers.
Kruger Park News then reported that although the algae were directly to blame for killing the animals, a variety of factors had combined to create the algal bloom conditions.
Both dams were man-made structures cut off from river systems and depending on rainfall to fill up. They are also home to large hippo populations, that defecate and urinate in the water, effectively fertilising the water for the benefit of the algae.
“An uncommonly warm winter, lots of hippos and an ever-decreasing body of stagnant water all combined to give the blue-green algae a chance to multiply frantically and produce their toxic by-products that eventually led to the death of at least ten different species of animals. Ironically, a hippo was amongst the casualties.”