Tag Archives: climate change

Lobsters Turn to Cannabalism

An adult lobster eats a tethered juvenile lobster (as indicated by the arrows) in these handout pictures taken from an infrared camera on the ocean floor near Maine. Graduate student Noah Oppenheim, has been documenting the phenomenon using a special infrared camera that allows him to observe a juvenile lobster tethered with a rope to a spot on the ocean floor. During the daytime, it is fish that typically feed on the tethered juvenile lobsters, but at night the researchers were stunned to see that most of the attacks on the small lobsters were by their larger brethren. REUTERS/Gregory Oppenheim/Handout

An adult lobster eats a tethered juvenile lobster (as indicated by the arrows) in these handout pictures taken from an infrared camera on the ocean floor near Maine. Graduate student Noah Oppenheim, has been documenting the phenomenon using a special infrared camera that allows him to observe a juvenile lobster tethered with a rope to a spot on the ocean floor. During the daytime, it is fish that typically feed on the tethered juvenile lobsters, but at night the researchers were stunned to see that most of the attacks on the small lobsters were by their larger brethren. REUTERS/Gregory Oppenheim/Handout

Off the coast of the USA, big lobsters have started eating their little brethren in a move never before recorded in the wild.

This is a fascinating case study of population change in the face of climate change and overfishing. And this time it’s about a population that is not only surviving – it’s changing behaviour too.

Warming waters in the Gulf of Maine and decreased predators due to overfishing have led to a huge population increase in recent years. A record 104 million pounds (45 million kilograms) were caught in 2011, compared with 23 million pounds in 1981. 2012 is expected to be even higher.

Lobsters are no stranger to aggressive interaction: they will attack each other when confined in a small space. But now encounters with each other in the Gulf of Maine are becoming so frequent that a predator-prey interaction has come about.

In a study by researchers from the University of Maine, they found that fish were the main lobster predator during the day. But the populations of cod, halibut and other groundfish that feed on lobsters has declined due to overfishing, and in a surprising find, 90% of predation on juvenile lobsters at night was due to older, bigger lobsters feeding on their younger brethren.

The Maine researchers believe this is the first time such behaviour has been visually documented in the wild, although Canadian researchers have also recently found evidence of cannabilism by examining lobster stomach content.

In an interesting contrast, warming waters have led to more disease and lower populations in Long Island Sound and southern New England. The increased abundance (and thus lower cost) of Maine lobster has also led to tensions with Canadian fishermen.

To read the original article from Reuters, click here.

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New Climate Watch App for Smartphones

ClimateWatch App ScreenshotA new iPhone app from ClimateWatch, a citizen science project started in 2007 by EarthWatch Australia, allows the public to record species sightings and help scientists to track climate change impacts.

Using the free app, you can record animal, bird, plant and insect behaviour and distribution.  This data can then be used to help understand how Australia’s environment is responding to climate change.

So far there are over 25,000 data points recorded on the website launched in 2010, and more than 5,000 registered users.

You don’t have to be an expert to take part.  You can record sightings when bushwalking, at the beach, or whilst sitting having a coffee in town.  Even with limited mobile reception, observations can be recorded with GPS, time and date stamps.

ClimateWatch is working with scientists on analysing and presenting the data for use in reports and research.  They’re looking at introducing the app into universities, and partnering with other citizen science projects such as Tasmania’s Red Map which tracks marine species.  This will help to complement the data gathering process in areas it doesn’t cover yet.

Citizen science projects are when “scientists and researchers ask the public to deliver data on a large scale to further research.  Large amounts of data can be gathered, processed or analysed faster to help researchers track trends and patterns.”

Read more at Science Network WA.  Then go get the FREE app from ClimateWatch and start recording!  (And for users without iPhones, Android is coming soon…)

 

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Half the Great Barrier Reef has Disappeared

Crown of Thorns Starfish. Image: AIMSDid you hear the depressing news this week that the Great Barrier Reef is declining faster than ever? A study by the Australian Institute of Marine Science found that the GBR has lost half its coral in only 27 years, and the rate of decline has worsened since 2006.  It is now at a coral cover level of 13.8%, and scientists predict we may only have 5% coral cover by 2022.

Whilst nearly half the damage since 1985 was caused by cyclones, 42% was caused by the destructive activity of the coral-eating crown-of-thorns starfish, and 10% by spikes in sea temperature causing widespread bleaching.  Importantly, coral cover could have increased if not for the starfish problem, but outbreaks of them have become ever more common, likely increased by fertiliser and pesticide run-off.

The study says that the reef could recover if the crown-of-thorns starfish numbers were reduced… and climatic conditions were stabilised.  Since the reef is also threatened by ocean acidification (which reduces the ability of coral to form its calcareous skeleton), trying to stabilise at least the local climate could make a huge difference.

Unfortunately, that’s not the only problem facing the Great Barrier Reef.  The ever-expanding coal and LNG industry along the Queensland coast threatens to turn this once pristine environment into a shipping highway, with all the associated risks of pollution, run-off, and oil spills.  UNESCO recently criticised the Australian government for failing to adequately protect the reef, warning that coastal development offered “serious concerns over its long-term conservation”.  The listing of the GBR as a World Heritage Site could be changed to ‘World Heritage Site in danger’ in a matter of months if steps aren’t taken to better protect it.  But the QLD government says they won’t jeopardise the economic future of the state.

Queensland and federal governments have since launched a review to determine how they can better manage the Great Barrier Reef alongside increasing urban and industry development.

Meanwhile, scientists are working on novel ways to protect the reef, and say that improved water quality is certainly key.

Queensland MP Bob Katter wants to put a bounty on the crown-of-thorns starfish… But the Environment Minister says that research and government-assisted culling is the way to go.  (The starfish’s spines are poisonous by the way… I know I wouldn’t dive for them!)

Green groups such as Greenpeace, the Australian Marine Conservation Society, WWF, the Australian Conservation Foundation and many others have ongoing campaigns aimed at raising awareness of the reef’s plight, trying to stop the destructive development plans along the coast, and improving water quality.  If you are concerned or want to learn more, I suggest heading over to their websites to sign up your support.

It would be Australia’s greatest shame to lose the Great Barrier Reef.  But if we don’t act now, that day is fast approaching.

 

 

 

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