This video says about itself:
10 April 2010
Critically endangered around the world, Australia is the last bastion for the Freshwater Sawfish (Pristis microdon). The team from Cairns Marine venture into the remote and inhospitable regions of the southern Gulf of Carpentaria, home to an abundance of crocodiles, in order to collect a small number of juvenile specimens for conservation and display in public aquaria.
From Murdoch University in Australia:
Freshwater fish under pressure
Friday, 26 February 2010
Sources of groundwater such as springs are helping keep threatened species alive, by providing a supply of good water.
Habitat change, decline in water quality and introduction of exotic fishes has had a major impact on the freshwater fish of the South-West, according to Murdoch freshwater fish experts Drs David Morgan and Stephen Beatty.
The Centre for Fish and Fisheries Research researchers say extensive surveys in every river system in Western Australia’s South-West have shown major range reductions and loss of populations of the region’s unique freshwater fishes, a number being listed as endangered. …
“These areas of fresh groundwater intrusions in systems such as the Blackwood River effectively dilute the main channel and maintain permanent tributary habitats for threatened species, such as the Balston’s Pygmy Perch, and therefore it is very important to maintain this input – particularly in light of the predicted reduction in rainfall due to climatic change in the South-West,” Dr Beatty said.
“The surveys have mapped the introduction and colonisation of feral fishes such as goldfish [see also here] and mosquitofish that are also having a massive impact on these fishes.
“In fact, our research has shown that there are now more species of exotic fishes than natives in these waterways, with a number of new species having being recently recorded.”
The Freshwater Sawfish (also known as the Largetooth Sawfish or Leichhardt’s Sawfish) is a critically endangered species that can be found between latitudes 11 N and 39 S in the Indo-West Pacific oceans. It grows up to 23 ft (approx. 7 m) in length: here.
New species of stingray discovered off Western Australia: here.
Talking about fish in Australia; from the University of Queensland:
Poisonous friends help mimic
Friday, 26 February 2010
UQ research has found being a copycat works out pretty well for a certain reef fish.
Dr Karen Cheney, from the School of Biological Sciences, has revealed the secrets of an underwater imposter – the bicolour fangblenny.
“This fish resembles another poisonous reef fish – the yellowtail fangblenny – to avoid predator attack and to also avoid detection from passing reef fish, which they approach and attack to gain a meal of skin and fins,” Dr Cheney said.
“This is the first example of a mimicry system in which the mimic gains multiple benefits from its resemblance to another species.”
The research, conducted at Hoga Island, Indonesia, and at Lizard Island on the Great Barrier Reef, involved observing the number of attacks made by the mimic and how close it stayed to the fish it resembled.
Mimics who stayed in close proximity to models were more likely to be successful in securing food, Dr Cheney found.
To investigate whether the mimics also benefited from a reduction in predator attacks, Dr Cheney placed replicas – photographs glued to Perspex – of the bicolour fangblenny among potential predators.
“Significantly fewer predators approached the true replica compared with the other replicas,” she said.
Dr Cheney said it was possible that the mimic used its colour as a signal to warn potential predators not to attack.
A previous study conducted by Dr Cheney confirmed cleaner fish – which remove parasites from passing reef fish – used colour to advertise their services.
The study will be published in Proceedings of the Royal Society B on February 24.
In a remarkable new finding, scientists have reported that certain coral reef fish use ultraviolet (UV) vision to tell the difference between their own and other similar species: here.
Top 10 Most Endangered Fish Species: here.
Britain: Teenage angler reels in 5lb goldfish: here.
March 2011. A biologist from the University of Toronto has discovered a new kind of tropical freshwater stingray. Dr Nathan Lovejoy’s 10 years of research with his collaborator, Marcelo Rodrigues de Carvalho of the University of Sao Paolo, confirmed the first new genus of stingrays from the Amazon region in more than two decades: here.
Object Recognition in Fish: Scientist trains goldfish to touch objects for food rewards: here.