Chapter 3

“Restoring the Strait of Georgia Ecosystem is sound economic policy”.

Fisheries, the extraction of living aquatic organisms for food and profit by humans, are embedded in natural aquatic ecosystems that are imperfectly understood. Despite a long history of sophisticated numerical analysis, the management of fisheries presents a dismal series of collapses and dissipation of rent that calls for both explanation and remedy (Pitcher & Pauly, 1998).

Overcapacity, i.e., the excessive deployment of people and machines to catch fish vis a vis the natural growth rate of the fish, is a major world-wide bio-economic problem that no one seems to be able to arrest (Mace, 1997). Generating overcapacity has been termed “Ludwig’s Ratchet” (Ludwig et al., 1993) (Pitcher, 2000). Unfortunately, human responses to these difficulties in terms of management actions and commercial fishing decisions tend to be maladaptive, despite the hope that co-management may alleviate some of these problems (Haggan, 1998) (Hart & Pitcher, 1998) (Pinkerton & Weinstein, 1995) (Pinkerton, 1989). Grounded in single species thinking and repeated by almost all mainstream fisheries economists since then, Beverton and Holt predicted that fishers will cease fishing when a stock becomes depleted (Pitcher, 1998, 1998). But all that fishing capacity is likely to be used, and evidence suggests that fishers try to maintain their income by switching to species of lower economic value further down the food web when more valuable high trophic level fish become depleted (Sumaila, 1999) (Pauly et al., 1998).

Another contributory reason underlying fishery collapses, is that management has not been able to learn in the face of errors in data, uncertain assessment and imperfect control instruments, despite the long availability of quantitative methods for adaptive management (Bundy, 1998) (Hilborn & Liermann, 1998).

But a more fundamental reason for fishery collapses is the long-term impact of fishing on the species composition of aquatic ecosystems. Through several direct and indirect effects, fishing alters niches towards generalist, k- selected species, leading to simpler ecosystems, higher volatility and, as noted above, lower value and trophic levels. The ecological processes leading to these changes, termed “Odum’s Ratchet” (Pitcher, 2000), are difficult to reverse and are, as yet, imperfectly understood. Through this process, fisheries use up ever higher proportions of primary production (Christensen & Pauly, 1995) and large high-value species with specialized niches are rapidly lost (Christensen & Pauly, 1998). A consequence is that so-called ‘trash’ fish come to replace high-value table fish, a process which has reached worrisome levels in the South China Sea, Gulf of Thailand and Black Sea, and is proceeding unchecked almost everywhere else. The emergence of new fisheries for cephalopods and jellyfish supports the notion of such a world-wide shift in the nature of exploited marine ecosystems (Caddy & Rodhouse, 1998). This ecological mechanism suggests that future overfishing will occur at an increasing rate (Pauly, Christensen, et al., 1998).

Avoiding the profound changes in aquatic ecosystems that are wrought by fisheries requires a major change in the philosophy underlying fisheries management (Pitcher & Pauly, 1998). Traditional single-species fish stock assessment, although necessary for computing the details of age structure and population biomass, is simply incapable of providing the information to remedy or reverse this process (Pitcher, 2000a) . What is needed is an evaluation of the impacts of fishing on aquatic ecosystems, and the adoption of policy goals that aim to maximize total benefits to society, by comparing the fisheries in alternative exploited ecosystems (T. J. Pitcher & Pauly, 1998) (T. J. Pitcher, 2000b) (T. J. Pitcher, 1998a, 1998a) (T. J. Pitcher, 1998c). This agenda requires multispecies, ecosystem-based assessment models.

The essential features of these techniques are, first, to model reconstructions of past and alternative ecosystems (Pauly, Pitcher, et al., 1998) and second, to evaluate their economic values if they were to be restored, including the costs and uncertainties of restoration. The policy goal for management then becomes the restoration of the ecosystem that maximises net benefits to society. We term this the “Back to the Future” (BTF) policy process. This is a fundamentally different process from the conventional use of sustainability as a policy goal, which, at worst, may serve only to sustain the present misery (Haggan, 2000) (Haggan et al., 1999) (T. J. Pitcher & Pauly, 1998). Adopting the BTF method counters the tendency to use as a baseline the state of things as they were at the start of our careers: a cognitive impediment to comprehending the full effects of fishing on aquatic abundance and biodiversity that has been termed “Pauly’s ratchet” (Pauly, 1995) (T. J. Pitcher, 2000b). BTF also effectively counters the two other ratchets, Odum’s and Ludwig’s, described above. Previous publications have described various aspects of the BTF method, and provide details of its rationale (T. Pitcher et al., 1999): In this paper we concentrate on the economic basis for the BTF process.

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