THREATENED RIVER SHARKS REDISCOVERED AFTER 45 YEARS
Scientists recently discovered two species of shark river after analyzing the DNA of these fishes in a market in Papua New Guinea. These represent the first records of both species in the country since the 1960s and 1970s and highlight the lack of studies of shark biodiversity.
The river sharks (Carcharhinidae: Glyphis) are a relatively poorly known group of sharks with patchy distributions in tropical rivers and coastal regions of the Indo-West Pacific
The fact that adult speartooth sharks
, a large apex predator, have thus far gone unnoticed highlights the rarity of river sharks which combined with their occurrence in remote, poorly-surveyed regions, have resulted in Glyphis species being some of the least known sharks
Despite their large size, they are not considered a danger to humans due to their extreme rarity. Experts believe there are less than 2,500 mature individuals of this species in the entire world, and no more than 200 in any one local population.
Photograph: Freshly caught specimen of New Guinea river shark (Glyphis garricki)
The New Guinea river shark, which is generally slightly larger, is even more rare. Fewer than 250 mature individuals are believed to exist.
Freshly caught adult males of
speartooth shark (Glyphis glyphis)
White et al 2015 Rediscovery of the Threatened River Sharks, Glyphis garricki and G. glyphis, in Papua New Guinea. PLoS ONE
She is free in her wildness, she is a wanderess, a drop of free water. She knows nothing of borders and cares nothing for rules or customs. ‘Time’ for her isn’t something to fight against. Her life flows clean, with passion, like fresh water.