Australian freshwater fish endangered


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.

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.

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.”

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.

3 thoughts on “Australian freshwater fish endangered

  1. Qld govt didn’t want Barrier Reef listed

    Published 11:59 AM, 2 Jan 2011 Last update 11:59 AM, 2 Jan 2011

    AAP

    The Joh Bjelke-Petersen Queensland government furiously opposed the World Heritage declaration of the Great Barrier Reef 30 years ago, arguing only sections of it should be protected.

    Newly released cabinet documents from 1980 show the coalition government was dead against the reef’s listing – which happened in 1981.

    Current Queensland Public Works Minister Robert Schwarten, who has released the cabinet documents, said the Bjelke-Petersen government’s intention had been to do exploratory mining on the reef for oil.

    Originally raised in January 1978, the idea to list the reef was set to be debated by the Australian Heritage Commission in February, 1980.

    A month before that, cabinet resolved to send a letter to the commission reaffirming the Queensland government’s objection to that.

    It said the Great Barrier Reef Marine Park Authority already existed to assess the “conservation, management and economic potential” of the area.

    “By examining the Great Barrier Reef region by region, the Authority has acknowledged that there are areas of differing conservation potential,” the letter said.

    “… It would be appropriate, therefore, to list only areas of prime ecological significance on the Register as they are assessed and identified by the Great Barrier Reef Marine Park Authority.”

    Mr Schwarten said it was interesting to compare the environmentally-aware world of 2010 to 1980, when the environmental debate began in Queensland.

    “The environment was foremost on everybody’s lips but for the wrong reason,” he said.

    “… Ironically, one of the sticking points was that the Queensland government was demanding payment for the mining rights from the reef east of Cairns.

    “Can you imagine anybody suggesting today that we mine on the Great Barrier Reef or that the Queensland government is looking for compensation to not mine on it?”

    The Great Barrier Reef is the world’s largest World Heritage Area and is the world’s most extensive coral reef system, celebrated for its rich biological diversity.

    http://www.businessspectator.com.au/bs.nsf/Article/Qld-govt-didnt-want-Barrier-Reef-listed-CPVMA?opendocument

    Like

  2. Pingback: BP oil kills fish | Dear Kitty. Some blog

  3. Pingback: Saving freshwater fish species and aquariums | Dear Kitty. Some blog

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.