Oct 062014
 

Original story at The Guardian

Spiny damselfish study suggests it would take at least several generations for fish to start coping with climate change.
Spiny damselfish, Acanthochromis polyacanthus. Photo: Flickr/creative commons.

Spiny damselfish, Acanthochromis polyacanthus. Photo: Flickr/creative commons.

Rising carbon dioxide levels in oceans adversely change the behaviour of fish through generations, raising the possibility that marine species may never fully adapt to their changed environment, research has found.

The study, published in Nature Climate Change, found that elevated CO2 levels affected fish regardless of whether their parents had also experienced the same environment.

Spiny damselfish were kept in water with different CO2 levels for several months. One level was consistent with the world taking rapid action to cut carbon emissions, while the other was a “business as usual” scenario, in which the current trend in rising emissions would equate to a 3C warming of the oceans by the end of the century.

The offspring of the damselfish were then also kept in these differing conditions, with researchers finding that juveniles of fish from the high CO2 water were no better than their parents in adapting to the conditions. Continue reading »

Sep 162014
 

Original story at ABC News

Three-quarters of the trash found off Australian beaches is plastic, a new study says, warning that the rubbish is entangling and being swallowed by wildlife.
Litter impacts wildlife through entanglement and ingestion, with 43 per cent of seabirds from study discovered with plastic in their gut.

Litter impacts wildlife through entanglement and ingestion, with 43 per cent of seabirds from study discovered with plastic in their gut.

Researchers surveyed the vast Australian coastline at intervals of about 100 kilometres, compiling the world's largest collection of marine debris data, the Commonwealth Scientific and Industrial Research Organisation (CSIRO) said.

"We found about three-quarters of the rubbish along the coast is plastic," CSIRO scientist Denise Hardesty said.

"Most is from Australian sources, not the high seas, with debris concentrated near cities."

The report, part of a three-year marine debris research and education program developed by Earthwatch Australia with CSIRO and energy group Shell, found there were two main drivers of the pollution - littering and illegal dumping.

Rubbish found included glass and plastic bottles, cans, bags, balloons, pieces of rubber, metal and fibreglass, as well as fishing gear and other items lost or discarded in or near the sea.

The report said this marine debris not only posed a navigation hazard but could smother coral reefs, transport invasive species, harm tourism and kill and injure wildlife.

It warned that litter impacted wildlife through entanglement and ingestion, but also indirectly via the chemicals it introduced into marine ecosystems.

Smaller turtle species in particular ingested the debris, possibly because soft, clear plastic resembled its natural prey jellyfish. Continue reading »

Jul 192014
 

News release from The University of Exeter

The tiny plastic particles polluting our seas are not only orally ingested by marine creatures, but also enter their systems through their gills, according to a new study led by the University of Exeter.
Photo: Shutterstock

Photo: Shutterstock

Scientists also discovered that when microplastics are drawn in through this method they take over six times longer to leave the body compared with standard digestion.

Lead author Dr Andrew Watts of Biosciences at the University of Exeter said: “Many studies on microplastics only consider ingestion as a route of uptake into animals. The results we have just published stress other routes such as ventilation. We have shown this for crabs, but the same could apply for other crustaceans, molluscs and fish – simply any animal which draws water into a gill-like structure to carry out gas exchange.

“This is highly important from an ecological point of view, as if these plastics are retained longer within the animal there is more chance of them being passed up the food chain.”

The researchers used fluorescently labelled polystyrene microspheres to show how ingested microplastics were retained within the body tissues of the common shore crab, Carcinus maenas. Multiphoton imaging suggested that most microspheres were retained in the foregut after sticking to hair-like ‘setae’ structures within the crabs. Continue reading »

Jul 172014
 

Original story by Jake Sturmer, ABC News

A world-first study has found that dredging can more than double the level of coral disease in reefs.
Joe Pollock researches the impact of dredging on coral. He says his study on the impacts of dredging highlights the pressure reefs face. Photo: Ed Roberts

Joe Pollock researches the impact of dredging on coral. He says his study on the impacts of dredging highlights the pressure reefs face. Photo: Ed Roberts

Scientists have known for decades that dredging can smother corals, but researchers say this is the first time it has been linked to diseases.

With dredging approved in the world heritage listed Great Barrier Reef Marine Park, the scientists hope their work draws attention to the pressing issues facing the region.

The study by the Australian Research Council's Coral Reef Studies Centre of Excellence looked at the 7 million cubic metres of dredging done for Chevron's Gorgon Gas Project off Western Australia's coast.

"There was a fair bit of dredging going there and this was an ideal opportunity to use this natural experiment to look at the impacts of dredging, sediment and turbidity on coral health," lead author Joe Pollock said.

"What we've found is that you get two times as much coral disease near the dredge sites as you do at nearby control sites."

Not all diseases are fatal but Mr Pollock said they can have a significant impact on reef health. Continue reading »

Jul 092014
 

Original story by Bianca Nogrady, ABC Science

Plant-eating tropical fish species are causing serious damage to algae and kelp forests in sub-tropical and temperate regions around the world, an international team of experts warn.
Pretty tropical fish are devastating kelp forests. Photo: Adriana Verges

Pretty tropical fish are devastating kelp forests. Photo: Adriana Verges

The findings come from a review published today in the Proceedings of the Royal Society B, which suggests that climate change is leading to 'tropicalisation' - the movement of tropical species towards the poles - as waters get warmer and ocean currents strengthen.

It reveals how algae and kelp-eating tropical fish such as rabbitfish have already led to the collapse of kelp forests - and their associated abalone fisheries - in Japan, and decimated the canopy-forming algae forests in the Mediterranean.

Two herbivorous tropical species - rabbitfish and drummer fish - have also been implicated in the loss of kelp forests on both the east and west coasts of Australia, says lead author of the study Dr Adriana Verges, marine ecologist at the University of New South Wales.

Overgrazing of algae and kelp by fish hampers recovery of the ecosystem from events such as heatwaves. Continue reading »

Jul 062014
 

Original story at Australia Network News, ABC

Scientists are concerned that hundreds of thousands of tons of plastic waste floating in the ocean is being eaten by fish.

Scientists believe fish may be eating tons of plastic waste. Photo: Great Barrier Reef Marine Park Authority

Scientists believe fish may be eating tons of plastic waste. Photo: Great Barrier Reef Marine Park Authority

An international team of experts has found evidence there is 100 times less plastic on ocean surfaces than expected.

Professor Carlos Duarte, an oceanographer from the University of Western Australia, was part of the study that towed a mesh net through the world's oceans.

He told Pacific Beat there are a number of possibilities for where the missing plastic has gone but one stands out.

"The disturbing reality is that we cannot account for where the 99 per cent that is missing may be," he said.

"The plastic particles that are missing might be ingested by fish. That one possibility is... the most likely one." Continue reading »

Jul 032014
 

Original story from the Society for Experimental Biology via EurekAlert!

This image shows tropical damselfish (Chromis viridis) schooling in a coral reef. Photo: Lauren Nadler

This image shows tropical damselfish (Chromis viridis) schooling in a coral reef. Photo: Lauren Nadler

Like humans, fish prefer to group with individuals with whom they are familiar, rather than strangers. This gives numerous benefits including higher growth and survival rates, greater defence against predators and faster social learning. However, high carbon dioxide levels, such as those anticipated by climate change models, may hinder the ability of fish to recognise one another and form groups with familiar individuals.

Scientists at the ARC Centre of Excellence for Coral Reef Studies at James Cook University, Australia, have been studying the effect of carbon dioxide on the schooling behaviour of the tropical damselfish Chromis viridis. Lead investigator Miss Lauren Nadler found that juvenile fish normally require three weeks to recognise their school-mates, however elevated carbon dioxide levels significantly impaired this ability. Continue reading »

Jun 082014
 

news release from The Ocean Cleanup

Feasibility study proves efficiency and financial viability

The Ocean Cleanup, founded by Dutchman Boyan Slat, has unveiled its feasibility report today, concluding that its concept is a viable method to clean the oceans from plastic. The report is the result of more than a year of extensive scientific research in engineering, oceanography, ecology, maritime law, finance and recycling. The feasibility study was financially supported by crowd funding and professional in kind contributions. The research was done by an international team of over 100 experts, predominantly on a voluntary basis. The next step, building and testing large-scale operational pilots, will be initiated as soon as sufficient funding has been raised.19-Year-old invents feasible solution to cleanup ocean garbage patches

The conclusions of the study mark the end of the first phase of the project in which the assumption that a cleanup of the infamous ‘Great Pacific Garbage Patch’ is impossible has been disproven. Within ten years’ time, almost half of the plastic could be removed. Continue reading »

Jun 072014
 

Original story by Damien Larkins and Russell Varley, ABC Gold Coast

Racehorse trainers and conservationists are angry at plans to fill in a wetland area near the Gold Coast Turf Club.
The wetland is home to a nesting black swan and dozens of other bird species. Photo: Damien Larkins

The wetland is home to a nesting black swan and dozens of other bird species. Photo: Damien Larkins

Trainers received an email on Thursday afternoon that work was going to start the next morning, as preparations continue for the Gold Coast Show to move to the Turf Club.

The email says the 2.75 hectare swamp area will be used for parking at the show and large race days but otherwise will be free for trainers to walk their horses the rest of the time. Continue reading »

Jun 042014
 

Original story by David Adamson and Adam James Loch, University of South Australia at The Conversation

The federal government’s approach for the Murray-Darling Basin Plan has shifted again, and now favours water-saving infrastructure over purchasing water rights. But is it the right move?
Spending on water-saving infrastructure could expose Murray-Darling farmers to debt and drought. Photo: Michelle Bartsch/Flickr, CC BY-NC-ND

Spending on water-saving infrastructure could expose Murray-Darling farmers to debt and drought. Photo: Michelle Bartsch/Flickr, CC BY-NC-ND

The new scheme proposes to cut the amount of water bought back from farmers by 200 billion litres — from 1,500 billion litres down to 1,300 billion litres. Continue reading »