Worldwatch Report: Oceans in Peril: Protecting Marine Biodiversity
Oceans in Peril: Protecting Marine Biodiversity
© NOAA and MBARI/Greenpeace
Uniquely among the universe’s known planets, the Earth is a sphere dominated by watery oceans. They cover 70 percent of its surface and are home to a myriad of amazing and beautiful creatures. Life almost certainly originated in the oceans, yet the biological diversity of marine habitats is threatened by the activities of one largely land-based species: us. The activities through which humans threaten marine life include overfishing, use of destructive fishing methods, pollution, and commercial aquaculture. In addition, climate change and the related acidification of the oceans is already having an impact on some marine ecosystems. Essential to solving these problems will be more equitable and sustainable management of the oceans as well as stronger protection of marine ecosystems through a well-enforced network of marine reserves.
Presently, 76 percent of the world’s fish stocks are fully exploited or overexploited, and many species have been severely depleted, largely due to our growing appetite for seafood. Current fisheries management regimes contribute to the widespread market-driven degradation of the oceans by failing to implement and enforce adequate protective measures. Many policymakers and scientists now agree that we must adopt a radical new approach to managing the seas—one that is precautionary in nature and has the protection of the whole marine ecosystem as its primary objective. This “ecosystem approach” is vital if we are to ensure the health of our oceans for future generations.
An ecosystem approach promotes both conservation and the sustainable use of marine resources in an equitable way. It is a holistic approach that considers environmental protection and marine management together, rather than as two separate and mutually exclusive goals. Paramount to the application of this approach is the establishment of networks of fully protected marine reserves—in essence, “national parks” of the sea. These provide protection of whole ecosystems and enable biodiversity to both recover and flourish. They also benefit fisheries by allowing for spillover of fish and larvae or eggs from the reserve into adjacent fishing grounds.
Outside of the reserves, an ecosystem approach requires the sustainable management of fisheries and other resources. Demands on marine resources must be managed within the limits of what the ecosystem can provide indefinitely, rather than being allowed to expand as demographic and market forces dictate. An ecosystem approach requires protection at the level of the whole ecosystem. This is radically different from the current practice, where most fisheries management measures focus simply on single species and do not consider the role of these species in the wider ecosystem.
An ecosystem approach is also precautionary in nature, meaning that a lack of knowledge should not excuse decision-makers from taking action, but rather lead them to err on the side of caution. The burden of proof must be placed on those who want to undertake activities, such as fishing or coastal development, to show that these activities will not harm the marine environment. In other words, current presumptions that favor freedom to fish and freedom of the seas will need to be replaced with the new concept of freedom for the seas.