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According to the Living Planet Report report, populations of fish, birds, mammals, amphibians and reptiles have declined by 52 per cent since 1970. Freshwater species have suffered a 76 per cent decline, an average loss almost double that of land and marine species. “Biodiversity is a crucial part of the systems that sustain life on Earth – and the barometer of what we are doing to this planet, our only home. We urgently need bold global action in all sectors of society to build a more sustainable future,” said WWF International Director General Marco Lambertini. Biodiversity declines in Africa highlight the intense pressure felt by tropical species. For the thousands of species tracked by the report, the tropics showed a 56 per cent loss across populations compared to 36 per cent in temperate zones. “The unique nature and natural resources of Africa are under more pressure than ever before. Life-sustaining ecosystems are rapidly degrading, thus compromising the future security, health and well-being of millions of African people, with the poor heavily and disproportionately bearing the brunt of these losses,” said Fred Kumah, Director of Africa at WWF International.

The International Union for Conservation of Nature, which publishes an annual global roster of threatened and endangered species called the Red List, considers some 664 species of reptiles — representing more than 20 percent of known reptile species worldwide — as endangered or facing extinction. Meanwhile, the U.S. Fish & Wildlife Service considers about 10 percent of American reptiles threatened or endangered. The non-profit Center for Biological Diversity (CBD) considers reptiles “amazing creatures” with clever adaptations that have helped them survive for millions of years. CBD also points out that reptiles are valuable indicators of wider ecological health. “Because many reptile species are long-lived and relatively slow-moving, they suffer from disturbances like habitat loss or pollution for extended periods,” the group reports, adding that a diverse community of reptiles living in a given area is evidence of a healthy ecosystem that can support the plant and animal life they and other species need for food and cover.

The removal of top predators has been called “humankind’s most pervasive influence on nature,” and it is as detrimental in the sea as it is on land. Consumers prefer predatory fish like grouper, tuna, swordfish and sharks to species lower on the food chain such as anchovies and sardines, providing strong incentives for fishermen to catch the bigger fish. Going after the more valuable predators first, fishing them until there aren’t enough left to support a fishery and then moving on to species lower in the food chain, a pattern sometimes observed in global fisheries, has been called “fishing down the food web.” New research by the team that coined the term attempts to determine how severely predatory fish populations have declined worldwide since the start of industrial fishing. Scientists analyzed more than 200 published food-web (interacting food chains) models from all over the world, which included more than 3,000 ocean species. Their results show that in the 20th century humans reduced the biomass of predatory fishes by more than two thirds and that most of this alarming decline has occurred since the 1970s.

The rivers and streams of the Paci­fic Northwest used to be so full of wild salmon that fishermen liked to say they could cross the waterways on the fish's backs. If salmon were the only means of crossing the rivers, those fishermen would be out of luck today. In California, Washington, Oregon and Idaho, salmon are extinct in nearly 40 percent of the rivers they were known to inhabit -- at least 106 major stocks gone forever [source: Northwest Power & Conservation Council]. Around the world, the story is much the same: Global Atlantic salmon catches fell 80 percent from 1970 to 2000. In the United Kingdom, one-third of the salmon population is endangered according to the WWF, and in California and Oregon, the Pacific Fishery Management Council recently announced the strictest salmon fishing quotas in the region's history due to the animal's rapid decline [source: Young, Environment News Service]. The downward spiral of the salmon population is troubling for several reasons. This fish is far more than just a tasty source of omega-3s. Salmon are what's known as a keystone species -- like the engine in your car, their physical presence compared to the whole is rather small, but their importance to its functioning is vital. Not only are the fish a main source of sustenance for a variety of predators (more than 137 species), but their decomposing carcasses are a significant source of nutrients and fertilizer for trees [source: Hunt]. When the salmon go, the surrounding ecosystem likely won't be far behind.

Neonicotinoids, broad-spectrum systemic insecticides, are the fastest growing class of insecticides worldwide and are now registered for use on hundreds of field crops in over 120 different countries. The environmental profile of this class of pesticides indicate that they are persistent, have high leaching and runoff potential, and are highly toxic to a wide range of invertebrates. Therefore, neonicotinoids represent a significant risk to surface waters and the diverse aquatic and terrestrial fauna that these ecosystems support. This review synthesizes the current state of knowledge on the reported concentrations of neonicotinoids in surface waters from 29 studies in 9 countries world-wide in tandem with published data on their acute and chronic toxicity to 49 species of aquatic insects and crustaceans spanning 12 invertebrate orders. Strong evidence exists that water-borne neonicotinoid exposures are frequent, long-term and at levels (geometric means = 0.13 μg/L (averages) and 0.63 μg/L (maxima)) which commonly exceed several existing water quality guidelines.