Editor’s note: Peter Kareiva is a lead scientist for The Nature Conservancy, a US-based NGO, and has been a faculty member of five US research universities. He has conducted research in North America, Latin America, Asia, and Europe over the past two decades, including in the fields of insect ecology, landscape ecology, risk analysis, mathematical biology, and conservation science. The following piece was adapted by MPA News from a longer essay by Kareiva, originally published this year in the journal Frontiers in Ecology and the Environment (1:9 [501-502]).
By Peter Kareiva
Marine conservation lags behind terrestrial conservation in funding, science, and implementation. The sluggishness with which we have come to focus on marine conservation is inexcusable. However, there is some advantage to not being first. In particular, we can learn from the successes and failures associated with longstanding systems of parks and preserves on land. As we race to establish MPAs, we should pause to consider the following lessons that are gleaned from our experience with terrestrial conservation:
- Terrestrial parks have often been located in the wrong places – typically those places that are of little economic value. In the US, for example, we have many national parks in areas of snow and rock, with little productivity or biodiversity. If we take a similar approach to marine conservation and place MPAs where political forces offer the least resistance, we will end up with an ill-designed network.
- Global climate change is real and represents a serious challenge to the design of any protected area network. Parks that are fixed in space therefore risk becoming obsolete. Clearly, consideration of resilience in the face of climate change should be part of any plan for MPAs.
- Invasive species are the greatest threat to terrestrial protected areas, but have not figured prominently in discussions of marine conservation. However, invasive species often dramatically alter marine ecosystems. MPAs will require as much protection against non-indigenous species as against harvest or other human disturbances.
- All too often, terrestrial conservation has focused on collecting long lists of species in a certain area, with little attention paid to the maintenance of critical ecological processes. In terrestrial systems, these processes include natural disturbances such as fires and floods. In marine systems, they could include freshwater inputs and re-colonization following large disturbances such as hurricanes. Whereas a relatively small area may capture many species within its borders, it usually takes a much larger area to protect ecological processes.
- On a related note, a myopic focus on the accumulation of long lists of species within the smallest possible area (biodiversity hotspots) can fail to protect the diversity of ecosystems and ecosystem services. A focus on species protection will typically lead to a very different allocation of conservation effort than would a focus on the conservation of ecosystem diversity. Both species protection and ecosystem protection should be considered in plans for marine conservation.
- Corridors and connections between terrestrial reserves are widely embraced in theory, but poorly documented with data. The same mismatch between theoretical appeal and empirical support is evident in marine discussions of “connectivity”. Before rushing to invest in marine corridors, we should await some convincing evidence of their effectiveness.
- The ecological status of the matrix in which terrestrial reserves are embedded can be as important as the integrity of the parks themselves. It may be impossible to achieve our conservation goals if we focus too narrowly on marine reserves to the neglect of the surrounding human-dominated landscapes and seascapes.
- No nature reserve system can be sustainable without also making sure that local human populations are provided for. This principle will certainly hold for coastal fisheries, which many local communities rely on for livelihood and food.
The critical difference between marine and terrestrial conservation has less to do with biology than with the policy context and political justifications used when arguing that marine areas should be set aside as protected. Specifically, advocates of no-take marine reserves commonly argue that the spillover of fish from within these areas can supplement harvest in surrounding zones, and hence provide a win-win conservation tool (biodiversity protection and increased harvest). Meanwhile, on land, no one asks that terrestrial protected areas produce a surplus of wildlife that spills over and supports surrounding hunting communities. Perhaps we should think about MPAs in the same way we think about terrestrial parks – simply as secure havens for biodiversity.
For more information:
Peter Kareiva, 4722 Latona Ave NE, Seattle, WA 98105, USA. Tel: +1 206 406 2249; E-mail: pkareiva@tnc.org