Scientists Call for Holistic Tropical Coastal Zone Management

More than 1.3 billion people worldwide – most in developing countries – depend largely on coastal marine zones them for food and livelihoods. These zones face declining health and productivity from pollution, overfishing and a myriad of other issues.

New regional-scale, science-driven approaches to governance of coastal marine zones need to be implemented in order to address the declining health and productivity of tropical coastal waters, according to a group of leading environmental and marine scientists.

Writing in the Marine Pollution Bulletin, 24 scientists from Canada, the U.S., the U.K., China, Australia, New Caledonia, Sweden and Kenya on July 2 called on governments and societies “to introduce and enforce use zoning efforts of Earth's coastal ocean waters, mirroring approaches commonly used to manage and protect land resources.”

“[O]ne fifth of humanity -- mostly in developing countries -- lives within 100 km (62.5 miles) of a tropical coastline. Growing populations and worsening climate change impacts ensure that pressures on tropical coastal waters will only grow,” they warn.

Managing the tropical coastal zone commons

A global commons, the ecological health and integrity of tropical coastal ocean waters often take a backseat to the demands societies place on them – from fisheries, aquaculture, shipping and tourism to oil, gas, mineral and energy exploration and production. Connected to the seas by streams and rivers, urban life, agriculture and industrial activities that take place far from the coasts are having a greater impact on the health and vitality of tropical coastal waters.

The tropical ocean ecosystem doesn't recognize national boundaries, yet human use of these waters has largely been governed by a hodgepodge of local and national institutional frameworks and agencies lacking the resources, capacity and wherewithal to carry out their missions.

According to the authors, attempts at sustainable management of coastal zone waters frequently fail today because they:

• are mounted at too small a geographic scale and/or over too short a period of time;


• focus on single issues (conservation, fisheries enhancement, land-based pollution) without regard to other problems that act together to degrade coastal environments;


• are imposed from "outside," often in a one-size-fits-all or cookie-cutter approach, without the consultation and consensus-building needed to gain real traction with the local community, management agencies or governments.

“While there are a few exceptional places," they write, "all too often, current management of development, habitat destruction, pollution, and overfishing is seriously inadequate.

The need for holistic, regional, ecosystems-based approaches

The authors warn that failure to implement holistic, regional-scale, science-driven approaches to coastal zone management will likely result in the following:

• Most coastal fisheries will be chronically overfished or collapsed;


• Loss of reef habitat will further reduce fisheries production and strain food security;


• Land-based pollution will increase to the extent that hypoxia and harmful algal blooms are routinely present;


• Pressures of coastal development will combine with sea level rise and more intense storms to further intrude on and erode natural coastlines, severely reducing mangrove, salt marsh and sea grass habitats;


• The cost of dealing with these impacts will further strain coastal economies, and the future for people on tropical coasts in 2050 will be substantially more bleak than at present.

Coastal zoning and marine spatial planning

In their paper, the 24 scientists call on governments and societies to implement “holistic, regional-scale management approaches to balance the growth in competing demands” that mirror those being taken to manage land resources. Lead author Peter Sales of the UN University's Canadian-based Institute for Water, Environment and Health, elaborated,

"We zone land for development, for farms, for parks, for industry and other human needs. Required today is a comparable degree of care and planning for coastal ocean waters.

"We have tended to think of the seas as our last great wilderness, yet we subject them, particularly along tropical shores, to levels of human activity as intense as those on land. The result is widespread overfishing, pollution and habitat degradation.

“Coastal marine management efforts today are just woefully inadequate to avoid irreparable degradation of the bounty and services on which so many people depend for food and well-being."

Recognizing the political difficulties, the scientists advocate much wider use of Marine Spatial Planning (MSP): “an objective procedure for partitioning portions of the coastal ocean among competing uses.” Using MSP, they add, “forces the regional-scale, holistic approaches to coastal management that nations desperately need.”

MSP is an integral part of coastal marine governance policy and planning for NOAA and the U.S. Bureau of Ocean Energy Management (BOEM), which has been using MSP tools and methods to design and implement plans to build America's first offshore wind power farms.

Sales and co-authors want to see such holistic approaches adopted much more widely, particularly among less developed tropical coast countries that are most vulnerable from the overexploitation and degradation of coastal waters, as well as rising sea levels and other effects associated with climate change.

"We propose making expanded use of marine spatial planning and zoning as a framework that will apportion coastal waters for differing activities, while forcing a multi-target and multi-scale approach, and achieving agreed ecological, economic and social objectives," Sales stated.

Image credits: 1) Ethan Daniels/Shutterstock; 2) Nature Climate Change 2, 239–242 (2012); 3) NOAA