Integration of Ocean Observations into an Ecosystem Approach to Resource Management

Abstract

Ocean observation programs are integral to the development of integrated ecosystem assessments (IEAs), which provide the scientific basis for ecosystembased management (EBM). Ocean observation programs provide the basis for assessing the state of marine ecosystems and understanding the impacts of natural and anthropogenic forcing. They also underlie the development and testing of ocean models, which provide understanding of marine ecosystem processes and enable prediction of future ecosystem states. Observation programs also serve to monitor the impacts of marine management strategies. We discuss the development of EBM in the USA and Europe and examine the role of ocean observation programs. In particular, we note the need for integrated ocean observation programs that monitor the physical, chemical, and biological state of the oceans, including the zooplankton and midto higher trophic levels of large marine ecosystems. The further development of such integrated programs will require cooperation across government, academic and other institutions. Ocean observation programs serve many societal needs, such as assessing water quality, the state of living marine resources, the influence of climate variability and climate change, and the impacts of various human activities that impinge on the coastal zone and oceans. A further, increasingly important use of ocean observation programs is as the basis for ecosystem-based management (EBM) of fisheries and of marine systems generally. Conventional fishery management has been based almost entirely on single-species stock assessment, which seeks to maximize long-term yield from a particular fishery in terms of biomass or economic return, treating the population in isolation from its physical and biological environment. This approach has been increasingly criticized, due to its widely perceived failure to sustainably manage global fisheries and the ecosystems they are imbedded within. As a result, there is growing interest in EBM methods [1-6]. Within an EBM framework, the key threats from fisheries include their impacts not only on target species, but on their predators and competitors, on bycatch species and benthic habitats. An EBM-based approach to management further implies that natural drivers of fish populations and ecosystem variability must be distinguished from anthropogenic impacts. The productivity of marine ecosystems and their fisheries vary on interannual (e.g. ENSO), decadal (e.g. the Pacific Decadal, North Pacific Gyre, and North Atlantic Oscillations) and other time scales [7-11]. However, there has been limited success to date incorporating climate variability into fishery management models [12]. Although EBM is often developed within a fisheries context, it should also include the impacts of other marine sector activities: pollution, coastal development, nutrient inputs potentially leading to coastal eutrophication, and introduced species. EBM approaches to marine management are now widely mandated, and interest in the subject has grown dramatically, with the number of papers published on the topic doubling approximately every five years since the 1970s (Fig. 1). However, there has been concern that the goals of EBM are vague and difficult to achieve. As a result, there has been considerable effort to operationalize EBM. It is our purpose in this paper to describe what is meant today by EBM, setting out its conceptual framework, and showing how it is developing into practice. In particular, we will examine the kinds of ocean observations necessary or useful in developing EBM and the role they play within the EBM conceptual framework. 1. THE EBM FRAMEWORK AND ITS SCIENTIFIC SUPPORT Pikitch et al [3] considered the overall objective of EBM to “sustain healthy marine ecosystems and the fisheries they support.” They broke this down into the following specific issues: • Avoid degradation of ecosystems as measured by indicators of environmental quality and