Tuesday 31 December 2013

Ghost Fishing and the Staggering Cost of Rubbish

















The following story was published in the Epoch Times Nov 1-7, 2013.




Not many people know what ‘ghost fishing’ is. It sounds scary and in fact is; but not for the reasons you might think.

Ghost fishing is when lost or discarded fishing equipment just keeps on catching fish. The caught fish die and attract more marine life to their death. This endless circle of destruction can go on for decades. 




In a recent report by Emily Rose Nelson of the R J Dunlop Marine Conservation Program she stated that something like 640,000 tons of fishing gear is lost or discarded at sea every year.

I did most of my marine research in northern Australia and we had teams working in the Gulf of Carpentaria; one of the country’s most productive fishing grounds. During a large scale beach clean-up 5,491 ‘ghost nets’ were collected. These are nets that washed ashore and don’t count many more entangled on the seabed. 

Carcasses and skeletons still in the nets showed that 80% of their catches were marine turtles. Of the 7 species, 5 are “endangered” or “critically endangered” and the other 2 are listed as “vulnerable” by the IUCN.




Further analysis revealed that the risk of entanglement was related to the number of ‘ghost nets’. As the deadly nets increase in numbers so too will the catching of marine turtles. Protecting turtles through legislation is of little benefit if their environment is laced with hazards they have no understanding of.

Here in the Andaman Sea most of the marine turtles are gone. Harvested for food and killed in trawling operations. But those few that survive and offer a small chance of population recovery face ‘ghost fishing’ on a mammoth scale. Fishing pressure is much higher in S E Asia than in northern Australia. There are no seasonal closures and fishermen discard enormous quantities of netting.

There isn’t a coral reef without bundles of net entwined in the coral and an invitation to the unsuspecting marine life. But it isn’t only fishing nets that kill the unsuspecting sea turtles. Fishermen throw lots of plastic into the sea. In the Andaman Sea, salt is used to hold the catch and the large white, plastic salt bags can be found floating everywhere.




Discarded plastic ‘shopping’ bags floating in the ocean resemble jellyfish, a common food of sea turtles. If a turtle eats plastic, it tends to clog the turtle's digestive system and results in the animal dying a slow and probably painful death. There have been many cases of turtle dissection showing plastic and other debris inside their stomachs and intestines.

When I worked with fishermen I saw lots of waste discarded overboard; they said there wasn’t enough room aboard to take it back to land. Surprisingly, they had enough room to bring it out with them. The price of being lazy and uncaring about our world is the loss of marine life in staggering proportions. If we continue this way we will have little to save and even less to fish for.






Friday 6 December 2013

The Butterfly Effect and Ocean Acidification






Will the Sea Butterfly be the victim of ocean acidification that causes a collapse of the ocean's food web?











Mathematicians working in physics, engineering, and biology have developed the concept of chaos theory. In a nutshell, this says that some processes are incredibly sensitive to the conditions at the time they start; things can turn out very differently with each tiny variation at the beginning.

This lead to the term, the Butterfly Effect, coined by Edward Lorenz (1917-2008) and creating the idea that much in nature is unpredictable.

I’ve always been intrigued by the theory; fascinated with such an absurd concept that seemed beyond proof and yet so believable. Could the beating of a butterfly’s wings really start the chain reaction that eventually grows into a whirlwind that destroys us all?

 
 The elegant sea butterfly is actually a tiny swimming snail

A few months ago I ran across an article in the Smithsonian Magazine about one of the most charming creatures in the ocean. Sea butterflies are tiny mollusks, ‘snails’ in fact, that are so light they are able to either fly through the shallow waters of the oceans or glide hanging upside down on the water’s surface using their foot. From a biologist’s perspective they are quite beautiful and very ‘cool’.

Called Pteropods, these fragile creatures are only a few millimeters long and have nearly transparent shells. Their shells look like those of their terrestrial cousins but are incredibly thin to make fluttering through the ocean possible. 


 


Sea butterflies number in the trillions from the tropics to the poles and eat enormous quantities of microscopic plankton, mostly plants, by entangling it in fine mucus ‘fishing’ nets. Their diet is the stuff that makes up the foundation of the ocean food pyramid and the sea butterflies are the first step in converting these plants into food for larger animals. At night many hunt at the surface and return to deeper water each morning.

Surprisingly, ocean food pyramids are rather short. Four or five steps usually gets to the top, to what are called the ‘apex’ predators. Of real importance is the fact that there is a lot less food at each level of the pyramid. Really large animals like many whales can’t find enough energy at the top and so take a shortcut and eat tonnes of plankton like tiny shrimps and of course, sea butterflies.

But man started a time bomb ticking at the end of the 18th Century when we began burning fossil fuels to power our industry and fulfill our dreams. In the USA, more than 90 percent of greenhouse gases come from fossil fuels. We now produce about 40 thousand tonnes of carbon dioxide every minute, double the earth’s ability to deal with it naturally.

 


The sea has been very obliging in the past and absorbed through biological and chemical processes about half of all the carbon dioxide that was produced since the industrial revolution. As the carbon dioxide combines with water molecules a chemical called carbonic acid is formed and this makes water just a little less alkaline and lowers its pH in a process called ocean acidification.

The effects of ocean acidification are already measurable. Emily Frost and Hannah Waters of Smithsonian’s Ocean Portal (May, 2013) report that the shells of sea butterflies in the arctic have already begun dissolving in the more acid sea. Now it is true that not all sea butterflies have shells, but unfortunately, those that don’t (the Gymnosomes) are predators of those that do. The shell-less species will perish along with the shelled ones as carbon dioxide levels continue to rise. Their loss may have a staggering impact on whales heading north to feed after calving in the tropics.

 
 Sea Butterflies that don’t have shells (the Gymnosomes) are predators of those that do

Whales may be the first alarm bell ringing as the effects of acidification and the loss of tiny shelled creatures spreads across the oceans. Closer to the equator are squid, anchovy and herring fisheries and the even larger tuna and mackerel they support.

Many species like the giant whale shark and basking shark are totally dependent on the lower levels of the food pyramid. The commercial fisheries most at risk supply about 40 percent of the protein to two thirds of the world’s population.


 
 The huge Basking Shark feeds only on very small fish and plankton


The plankton that is carried over the world’s coral reefs by ocean currents is the bringer of life; swarms of tiny creatures are caught by corals, sponges, clams, and colorful fish. The collapse of the coral reef food pyramid will be a disaster for the 200 million people that depend on its productivity for sustenance. 

Will everything in the ocean die?

The answer is definitely not. But the future ocean will be a lot different to the one we know today. There will be winners and losers in the race to survive. Those species unable to find suitable food will of course dwindle and face extinction. Those that shift to other prey species will bring enormous pressure to bear on their new food and cause the balance of the whole ecosystem to shift even farther. 

 

A few years ago (2009) , Martin Scheffer of Wageningen University in The Netherlands together with a number of other scientists published in the journal Nature.
They found that many things from climate, to nature, to finance show similar behaviours as they approach a point of change called a ‘tipping point’ where processes strike off in an unpredictable direction. "It's increasingly clear that many complex systems have critical thresholds -- 'tipping points' -- at which these systems shift abruptly from one state to another," write the researchers.

"The information comes at a critical time -- a time when Earth's and, our fragility, have been highlighted by global financial collapses and concern about rapid change in climate and ecological systems."

So what about the sea butterflies? We set an unknown course when we started to burn fossil fuels more than 200 years ago. With that new found power we remade the world and our lives to suit us but in the process we have ‘tread’ on the lives of a few tiny species that really do matter. They are the underpinning of much of our future and the lives of millions. We could not see the future then and perhaps we wouldn’t have cared anyway.


 


How ironic that when Edward Lorenz coined the expression, Butterfly Effect, in 1969 he described without knowing the  biological  cataclysm that would  throw the world into chaos  80 years later.

In the crystal waters of the Andaman Sea where whale sharks come to feed I can just see tiny sea butterflies a few centimeters below the surface. Their wings are beating now but for how much longer? Will it be their loss that really starts the chain reaction that eventually grows into an environmental ‘whirlwind’ that destroys us all?





If you are interested in some of the latest topics in ocean conservation check out some of the other posts on this site.

Gerry is a Malaysian based marine ecologist, Research Fellow and Advisor to the National University of Malaysia, and marine consultant to the Andaman Resort, Langkawi.


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Thursday 10 October 2013

Shark Attacks; The Real Story








I grew up in the ‘golden days’ of Miami and the Florida Keys. My teenage friends and I would often return to the wharf with 100 lobsters and we would catch sharks just for fun. The lobsters were good and the sharks were bad in my black and white world of wildlife. We believed there was no end to the supply of either animal.



My interest in sharks was like everyone’s – morbid. A shark attack with photos was front page news and each sparked debate in the dive clubs over the best way to avoid becoming the next victim. I sometimes carried a ‘bang stick’ (a rifle bullet fired from a short hand-held club) thinking I could fight these villains if it came to the worst.



When I started work on the Great Barrier Reef, I got a surprise. The sharks seemed bigger, more numerous, and very brave compared to their Caribbean brothers. Australian shark attacks were front page stories and dominated the news for days.


 
 Sharks are slow to approach a swimmer under the water.

And yet there I was working for hours every day, year after year within metres of these predators and all I had to do to avoid trouble with the tropical species was respect their territories and not swim around with speared fish on my belt.



The November issue of Conservation Biology published a review of media coverage of sharks. According to Meredith Gore, MSU assistant professor of fisheries and wildlife, Australian and U.S. news articles focused on negative reports featuring sharks and shark attacks instead of conservation efforts. "The most important aspect of this research is that risks from ­- rather than to -- sharks continue to dominate news coverage in large international media markets," said Gore.



So how real is the case against sharks?

 Every year about 100 shark attacks are reported worldwide. In 2011, just 17 fatalities out of 118 attacks were recorded as having being caused by sharks.  Although shark attacks are infrequent, there is a heightened awareness due to occasional serial attacks; “it’s out there and I’m next”. Horror fiction like Jaws (1975) appears on TV just often enough to keep this fear alive and even so-called “nature” shows only show sharks in frenzied feeding

 
 One of these is the most dangerous killer on Earth; the other is a shark.
Shark attack experts are adamant that the danger has been greatly exaggerated. According to the International Shark Attack File (ISAF), between the years 1580 and 2011 there were 2,463 recorded shark attacks around the world, of which 471 were fatal. Surprisingly, that’s only 1.09 fatalities per year for the last 431 years.

 Australia is ranked second in terms of global shark attacks with 877 attacks since colonial settlement in the 18th century; it’s ranked the highest in terms of shark fatalities, with only 217 during this long period.

The results of Gore’s Michigan State University study found that more than 52 percent of global coverage focused on attacks on people and sharks were portrayed as aggressive and dangerous in nearly 60 percent of the reports. Positive PR was tougher to find with only 10 percent of stories dealing with shark conservation and just 7 percent looking at biology and ecology.

According to Time/ CNN : Zoologists today estimate elephants around the world kill 500 people a year while the great white sharks (Jaws)  kill only 4 people.

Incredibly, there are about 24,000 lightning deaths (one every 20 minutes) and 240,000 lightning injuries annually (Royal Aeronautical Society, 2003). When was the last time we read stories of the lurking danger above or watched a movie where people were struck down like dominoes by searing thunder bolts?

Amazingly, Gore went on to point out that conservation groups were often quoted emphasising negative aspects of sharks and seldom the pressing conservation issues. "This suggests that conservation groups are either not being sought out by the media in regards to shark conservation issues or they are not engaging enough to make headlines," Gore said.



In writing this story I contacted 10 shark advocacy or shark ‘experience’ groups. After making them aware of my support for sharks I asked for additional information or photos in exchange for credit and support for their position. I received some brilliant photos (featured here) through Asian Shark Conservation and by Ellen Cuylaerts who was in the water with Epic Diving. The others have not replied.



Why is shark conservation so important and why is it being neglected?


The first part of this question is easy. Sharks are in big trouble! "Overfishing of sharks is now recognized as a major global conservation concern, with increasing numbers of shark species added to the International Union for the Conservation of Nature's list of threatened species," say Mizue Hisano, Professor Sean Connolly and Dr William Robbins from the ARC Centre of Excellence for Coral Reef Studies and James Cook University.


On March 1, 2013, "Global Catches, Exploitation Rates and Rebuilding Options for Sharks," was published by Dr. Worm and other researchers from Dalhousie University, the University of Windsor in Canada, as well as Stony Brook University in New York, Florida International University (FIU) in Miami and the University of Miami. A very powerful team of scientists.



Their shocking findings put the carnage at 97 million in 2010. The possible range of mortality falls between 63 and 273 million annually. This equates to somewhere between 7,200 and 31,000 sharks per hour.


 
As many as 31,000 sharks are killed every hour.

"In working with tiger sharks, we've seen that if we don't have enough of these predators around, it causes cascading changes in the ecosystem, that trickle all the way down to marine plants." Such changes harm other species, and destroy commercial fisheries, Mike Heithaus, executive director of FIU's School of Environment, Arts and Society explains.

"This is a big concern because the loss of sharks can affect the wider ecosystem," said Heithaus in March, 2013.

Why we are neglecting shark conservation is harder to answer. First, there have been powerful economic reasons to turn a blind eye to shark fishing and shark finning. The shark industry is worth about US$630 million annually according to a study published May 30, 2013 in Oryx – The International Journal of Conservation.

This equates to an average of $6.49 per shark. This may not be such a good reason but greed is a characteristic of human behaviour and we make lots of poor decisions because of it.

A second explanation comes from deep in the primitive part of our brains. Our prehistoric ancestors had the very same fears that we do according to Psychology Today. We were ‘designed’ to be afraid; fear was our operating manual for things we didn’t understand or that could do us harm. Fears protect us. “Our distant ancestors who were afraid of heights didn’t fall off cliffs, those that feared wild animals didn’t get eaten, those that ran the fastest left the rest behind---and they survived.” 

Surveys of people show different fears for different cultural groups but amazingly many fears are shared globally even for animals never encountered by the people who fear them. Top of the list is spiders and number 10 are alligators and crocodiles. Sharks come in at number six according to Animal Planet.


 
Sharks need to treated with caution but they aren't the killers they are made out to be.

Elephants are not on our list of feared animals and we donate millions of dollars each year to protect them even though they kill thirty times more people than sharks do. Why can’t we see that the health of our ocean hangs in the balance and that we are making decisions with our ancestor’s fears and not with our children’s futures in mind?

The first big step in the right direction was taken in July, 2011 when the Bahamas banned all shark fishing in its 630,000 square kilometres of ocean. "The Bahamian government had the foresight to protect - - sharks within their waters, starting with the longline fishing ban in early 90s, and culminating with the more recent shark sanctuary initiative," said Edd Brooks, program manager of the Shark Research and Conservation Program at the Cape Eleuthera Institute. "This level of protection is vital for the continued existence of these important apex predators, and I hope that the example set by The Bahamas will encourage other nations to follow suit."

Sharks do injure and kill people as do most other large animals and many other things we all take for granted in everyday life. I’ve spent thousands of hours in the water with sharks and do not see them as my enemy. Until we can deal with sharks honestly in both the media and our own minds we will not be able to protect them and the oceans they swim in.

As shark numbers plummet the ecological stability of the sea is lost and life-sustaining fisheries collapse. What a tragedy to discover we lost such an important battle through our own primitive fears and self deception.