LESS WILDLIFE MEANS MORE TERRORISM

The harvest of wild terrestrial and aquatic animals each year injects more than $400 billion dollars into the world economy. That harvest provides 15% of the planet’s human population with a livelihood. It’s also the primary source of animal protein for more than a billion of our species. It’s also led to piracy, slavery, and terrorism.

The over-harvest of wild animals, both from land and sea, has created a market defined by low supply and high demand. And that, according to UC Berkeley environmental scientist Justin S. Brashares and colleagues, has led to the proliferation of organized crime in some of the poorest parts of the world. Over-hunting and over-fishing have, at least in part, created conditions where human trafficking and terrorism can thrive.

The reason this is the case comes down to simple economics. “Wildlife declines often necessitate increased labor to maintain yields,” argues Brashares in this week’s issue of Science Magazine. To acquire increasingly scarce resources without the a simultaneous increase in costs, “harvesters of wildlife resort to acquiring trafficked adults and children…A vicious cycle ensues, as resource depletion drives harvesters to increase their use of forced labor to stay competitive.” Continue reading

Whales as ecosystem engineers

“Consider the subtleness of the sea; how its most dreaded creatures glide under water, unapparent for the most part,” wrote Herman Melville in Moby Dick. Today, we no longer dread whales, but their subtlety remains. “For a long time, whales have been considered too rare to make much of a difference in the oceans,” notes University of Vermont conservation biologist Joe Roman. That was a mistake.

Whales as ecosystem engineers

Huge blue whales plunge to 500 feet or deeper and feed on tiny krill. Then they return to the surface—and poop. This ‘whale pump’ provides many nutrients, in the form of feces, to support plankton growth. It’s one of many examples of how whales maintain the health of oceans described in a new scientific paper by the University of Vermont’s Joe Roman and nine other whale biologists from around the globe. Credit: Frontiers in Ecology and the Environment.

In a new paper, Roman and a team of biologists have tallied several decades of research on whales from around the world; it shows that whales, in fact, make a huge difference—they have a powerful and positive influence on the function of oceans, global carbon storage, and the health of commercial fisheries. “The decline in great whale numbers, estimated to be at least 66% and perhaps as high as 90%, has likely altered the structure and function of the oceans,” Roman and his colleagues write in the July 3, 2014, online edition of Frontiers in Ecology and the Environment, ” but recovery is possible and in many cases is already underway.”

“The continued recovery of great whales may help to buffer  from destabilizing stresses,” the team of scientists writes. This recovered role may be especially important as climate change threatens  ecosystems with rising temperatures and acidification. “As long-lived species, they enhance the predictability and stability of marine ecosystems,” Roman said.

Baleen and , known collectively as the “great whales,” include the largest animals to have ever lived on Earth. With huge metabolic demands—and large populations before humans started hunting them—great whales are the ocean’s ecosystem engineers: they eat many fish and invertebrates, are themselves prey to other predators like , and distribute nutrients through the water. Even their carcasses, dropping to the seafloor, provide habitat for many species that only exist on these “whale falls.” Commercial whaling dramatically reduced the biomass and abundance of great whales.

“As humpbacks, gray whales, sperm whales and other cetaceans recover from centuries of overhunting, we are beginning to see that they also play an important role in the ocean,” Roman said. “Among their many ecological roles, whales recycle nutrients and enhance primary productivity in areas where they feed.” They do this by feeding at depth and releasing fecal plumes near the surface—which supports plankton growth—a remarkable process described as a “whale pump.” Whales also move nutrients thousands of miles from productive feeding areas at high latitudes to calving areas at lower latitudes.

Sometimes, commercial fishermen have seen whales as competition. But this new paper summarizes a strong body of evidence that indicates the opposite can be true: whale recovery “could lead to higher rates of productivity in locations where whales aggregate to feed and give birth,” supporting more robust fisheries.

As whales recover, there may be increased whale predation on aquaculture stocks and increased competition—real or perceived—with some . But the new paper notes ” a recent investigation of four coastal ecosystems has demonstrated the potential for large increases in whale abundance without major changes to existing food-web structures or substantial impacts on fishery production.”

In death, whale carcasses store a remarkable amount of carbon in the deep sea and provide habitat and food for an amazing assortment of creatures that only live on these carcasses. “Dozens, possibly hundreds, of species depend on these whale falls in the deep sea,” Roman notes.

“Our models show that the earliest human-caused extinctions in the sea may have been whale fall invertebrates, species that evolved and adapted to whale falls,” Roman said, “These species would have disappeared before we had a chance to discover them.”

Until recently, ocean scientists have lacked the ability to study and observe directly the functional roles of whales in marine ecosystems. Now with radio tagging and other technologies they can better understand these roles. “The focus of much marine ecological research has been on smaller organisms, such as algae and planktonic animals. These small organisms are essential to life in the sea, but they are not the whole story,” Roman said.

New observations of whales will provide a more accurate understanding of historical population dynamics and “are likely to provide evidence of undervalued whale ecosystem services,” note the ten scientists who co-authored this new paper, “this area of research will improve estimates of the benefits—some of which, no doubt, remain to be discovered—of an ocean repopulated by the great .”

Source: http://phys.org/news/2014-07-whales-ecosystem.html#jCp
Explore further: Scientists use DNA to identify species killed during early whaling days

Journal reference: Frontiers in Ecology and the Environment

 

The Problem With Overfishing

Despite an increased awareness of overfishing, the majority of people still know very little about the scale of the destruction being wrought on the oceans. This film presents an unquestionable case for why overfishing needs to end and shows that there is still an opportunity for change. Through reform of the EU’s Common Fisheries Policy, fisheries ministers and members of the European Parliament, MEPs, can end overfishing. But only if you pressure them, October 23rd, ask MEPs to … www.votefish.org

Source: http://www.overgrowthesystem.com/the-problem-with-overfishing-an-animated-film-that-will-open-your-eyes/