A General Business Model for Marine Reserves 102417 1,2 3,4 3 5 6 Enric Sala *, Christopher Costello , Dawn Dougherty , Geoffrey Heal , Kieran Kelleher , Jason H. Murray7, Andrew A. Rosenberg8, Rashid Sumaila9 1 National Geographic Society, Washington, D. C., United States of America, 2 Centre d’Estudis Avanc ´ficas, Blanes, ¸ ats de Blanes, Consejo Superior de Investigaciones Cientı Spain, 3 Bren School of Environmental Science & Management, University of California Santa Barbara, Santa Barbara, California, United States of America, 4 Visiting Professor, Laboratoire Montpeillerain d’Economie The ´orique et Applique´e, Montpellier, France, 5 Columbia Business School, Columbia University, New York, New York, United States of America, 6 The World Bank, Washington, D. C., United States of America, 7 School of the Environment, University of South Carolina, Columbia, South Carolina, United States of America, 8 Union of Concerned Scientists, Cambridge, Massachusetts, United States of America, 9 Fisheries Centre, University of British Columbia, Vancouver, British Columbia, Canada Abstract Marine reserves are an effective tool for protecting biodiversity locally, with potential economic benefits including enhancement of local fisheries, increased tourism, and maintenance of ecosystem services. However, fishing communities often fear short-term income losses associated with closures, and thus may oppose marine reserves. Here we review empirical data and develop bioeconomic models to show that the value of marine reserves (enhanced adjacent fishing + tourism) may often exceed the pre-reserve value, and that economic benefits can offset the costs in as little as five years. These results suggest the need for a new business model for creating and managing reserves, which could pay for themselves and turn a profit for stakeholder groups. Our model could be expanded to include ecosystem services and other benefits, and it provides a general framework to estimate costs and benefits of reserves and to develop such business models. Citation: Sala E, Costello C, Dougherty D, Heal G, Kelleher K, et al. (2013) A General Business Model for Marine Reserves. PLoS ONE 8(4): e58799. doi:10.1371/ journal.pone.0058799 Editor: Athanassios C. Tsikliras, Aristotle University of Thessaloniki, Greece Received October 3, 2012; Accepted February 9, 2013; Published April 3, 2013 Copyright: ß 2013 Sala et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This research was funded by the National Geographic Society and the Waitt Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: esala@ngs.org Introduction will be crucial for determining if, and how, to achieve the targets of the Convention of Biological Diversity that call for protection of Marine protected areas (MPAs) are intertidal and/or subtidal 10% of the ocean (http://www.cbd.int/sp). areas that have been reserved by law or other effective means to Here we synthesize information on the ecological and economic protect part or all of the enclosed environment, including water, benefits of marine reserves, and use bio-economic modeling to flora, fauna, and historical and cultural features [1]. MPAs were show how marine reserves can be created and managed in a initially proposed as a means to preserve marine biodiversity and financially self-sustaining manner. This model incorporates both unique habitats, and as an opportunity for recreation, education fishery and tourism benefits over time following the designation of and research. Nevertheless, in the last two decades much of the a marine reserve. literature has focused on whether MPAs enhance nearby fisheries and produce economic returns [2,3]. There are many types of Ecological benefits of marine reserves MPAs, from areas where most fishing is allowed to no-take marine A review of peer-reviewed studies on 124 marine reserves in 29 reserves where fishing is prohibited. Because it is difficult to countries showed that, on average, marine reserves cause increases compare the benefits of areas with different levels of protection, of 21% in the number of species, 28% in the size of organisms, here we focus on no-take marine reserves only (‘‘marine reserves’’ 166% in density (number of individuals per unit area), and a hereafter). The literature is now quite clear about the conditions remarkable 446% in biomass, relative to unprotected areas nearby under which marine reserves produce economic and/or ecological [4]. However, the increase in biomass of predatory fish can be benefits (e.g., [4,5]). Yet in focusing almost exclusively on fisheries, greater than the above averages [6,7,8]. The increase in the this literature has ignored other, perhaps more important, aspects biomass of predators has been shown to produce a re-accommo- of the value of marine reserves. A prime example is the tourism dation of the food web, shifting from a degraded state typical of value of marine reserves which may increase over time as biomass intensely fished sites to a more complex, mature state. These food and diversity increase within the borders of a marine reserve. web changes can enhance ecosystem resilience by promoting the Simultaneously accounting for these, and other economic effects, recovery of populations of functionally important species (i.e. allows us to create a general model that provides the foundation strong interactors [9]). for a business case for marine reserves, taking care to estimate the Fisheries may benefit from reserves when they help replenish dynamics of payoffs from reserve implementation. Globally, nearby habitats through spillover of adult organisms and dispersal assembling economic arguments for, or against, marine reserves of larvae. The increase in the biomass of commercial species inside PLOS ONE | www.plosone.org 1 April 2013 | Volume 8 | Issue 4 | e58799 Marine Reserve Business Model marine reserves has been shown to increase reproductive output farther afield, to benefit fishers in other areas or with greater (e.g., [10,11]), as long as the reproductive grounds are included in mobility [15]. the reserves. A review by Lester et al. [4] showed that areas outside Tourism. The increase in marine life inside marine reserves, reserves showed a significant increase in biomass after the reserve in particular large fish, is the main attraction for divers and other was in place, possibly through the spillover of adults and/or the tourists, which can bring revenue disproportionately higher than export of larvae. Empirical studies also show that higher fishing (Table 1). In the wider Caribbean and Pacific coast of abundances inside reserves can lead to spillover of adults to Central America, for instance, 50% of all dives (7.5 million dives nearby fished areas (Table 1). Spillover at small scales is common annually) take place within marine protected areas [16], even for commercial species that respond positively to reserve though only 4% of Caribbean coral reefs are in MPAs rated as protection [12]. Empirical evidence on the ability of reserves to ‘‘good’’ or ‘‘partially effective’’ [17]. This strongly indicates the replenish fished areas through larval dispersal is limited, partly interest of divers to frequent areas with more abundant marine life. because of methodological/sampling issues [13], but there are Although no data exist on the general relationship between fish some remarkable examples (Table 1). biomass and diver frequentation, there is a clear preference for diving in MPAs because of the expectation of encountering more Economic benefits of marine reserves abundant marine life within their boundaries. Marine reserves can provide economic benefits through tourism Fishing. Well-enforced marine reserves can increase adjacent (diving, snorkeling, glass bottom boats), fishing (increase or fishery catches (Table 1). At small scales (on average within 1 km stabilization of catch around reserves), and other services, some from the reserve boundary), local fisheries would not be of which are difficult to quantify (e.g., insurance value, local sustainable without the reserves in 12 of 14 cases studied, and amenity value, storm protection, political value, intangible capital). spillover offsets losses in catch due to the creation of the reserve in A primary concern among fishermen is the loss of fishing grounds the other two cases [12]. For a full review of the effects of marine and yields that may occur when marine reserves are implemented; reserves on local fisheries see [18]. In addition to enhancing or these effects may not be offset by the increase in spillover and ensuring sustainable yield, marine reserves can also increase the dispersal of larvae provided by the reserves [14]. An additional long-term profitability of fisheries (Table 1). It is important to note concern is that establishing reserves may disadvantage some that the data are consistent with perceptions of the status of the fishermen such as local smaller vessels with less potential to work fishery by the local community. In the Apo Marine Reserve in the Table 1. Examples of economic benefits of marine reserves from fishing enhancement and tourism. Fishing Area Benefits Observations References Apo Marine Reserve, Philippines Enhancement of catch of jacks and Less fishing effort brought higher [19] surgeonfish catch rates Columbretes Islands Marine Reserve, Net gain of .10% in weight of the Caused by annual lobster spillover of [50] Spain local lobster fishery catch 7% of the protected population. Benefits outweighed the costs of the reserve creation `re Marine Management Soufrie Increased adjacent catches by 46–90% In only 5 years, despite a 35% [21] Area, Saint Lucia decrease in area of fishing grounds Sinai Peninsula Marine Reserves, 66% increase in catch per unit effort Within only five years of the creation [51] Egypt of the reserves Mombasa Marine National Park Fisher income near reserve 135% Profits increased despite heavy [24] higher than in open access areas fishing, diverse gear and catch, poverty, and unregulated markets Ucunivanua marine reserve, Fiji Clams became 7 more abundant in After only 5 years of protection. [13,40] the adjacent fished area Caused by larval dispersal. Georges Bank fishery closure Scallop recruitment increased around Scallop biomass increased over 14 times [52] the closed area over 4 years in the closed area, and produced significant larval dispersal Tourism Area Annual revenue Observations References Cabo Pulmo National Park, Mexico $12,000 per capita Higher than in most coastal [53] communities in Mexico Saba Marine Park, Netherland Antilles $3 million 22% of the local economy [54] Mombasa Marine National Park, Kenya $3.5 million km22 350 times higher than fishing revenue [55] [24] Medes Islands Marine Reserve, Spain J10 million In only 94 ha of no-take area. 20 [31] times higher than fishing revenue Great Barrier Reef Marine Park, AU$5.5 billion 36 times greater than income from [37] Australia commercial fishing, plus 54,000 full time jobs doi:10.1371/journal.pone.0058799.t001 PLOS ONE | www.plosone.org 2 April 2013 | Volume 8 | Issue 4 | e58799 Marine Reserve Business Model Philippines, for example, 67–100% of the fishers interviewed not been a significant issue to date on a global scale because only believed that the fishery was improved by the presence of the less than 1% of the ocean is protected in marine reserves. Marine reserve [19]. reserves are also criticized as insufficient tools for managing An additional value for fishing of marine reserves concerns fisheries. It is important to note that the current research does not catch-and-release recreational fishing inside the reserves, which suggest the replacement of alternative fishery management tools. may be compatible with the reserves provided that ecological Marine reserves provide the myriad benefits described above and impacts can be minimized [20]. Although recreational catch-and- may further complement traditional fishery management measures release angling causes some fish mortality, it is considered an in the long run. The next section presents a simulation model of amenity value, and it can bring more revenue than commercial the time path of marine reserve benefits and costs. fishing to local communities. A good example is the well-regulated fly-fishing operation at the Jardines de la Reina Marine Natural Methods Park, Cuba, which has an annual quota of sport fishers and provides a significant revenue stream. Alongside diving, fishing Creating marine reserves can be an economically optimal revenues help cover the management costs of the reserve and solution when the combined value derived from tourism, the provide employment for Cuban fishing guides. enhancement of local fisheries (via spillover from the reserve) and Recreational fishing outside reserves may also benefits from other services (see above) outweighs the value of any single use in spillover. In Florida, the no-take areas in the Merritt Island isolation in the now-protected area. In what follows we develop a National Wildlife Refuge have supplied increasing numbers of general dynamic model to simultaneously analyze these quantifi- world record–sized fish to adjacent recreational fisheries since the able effects of marine reserves on economic welfare. In particular, 1970s [21]. we develop a bio-economic model to simulate the value of a fishery Other services. Marine reserves help preserve and restore and the value of tourism over time for a fishery that implements a biodiversity at many levels (e.g., how many species and how many no-take zone. We then develop a focused case study to illustrate individuals of each species, and structure of the biogenic habitat; the economic effects of marine reserves. [22]). A meta-analysis showed that the increase of species diversity in marine reserves was associated with large increases in fisheries Biological model productivity, a reduction in the variability of aggregate fish Operating model. We use a delay difference model to biomass (which helps reduce uncertainty in fisheries), and an simulate the population dynamics of a single species, and increase in resistance and recovery after natural disturbances from parameterize the model to examine the effects on several species storms and thermal stress [5]. By restoring biodiversity, reserves with different characteristics. We assume a linear coastline divided enhance the productivity and reliability of the good and services into 100 areas. This model tracks the species biomass in each area that the ocean provides for humanity. each year and accounts for growth of average individuals. Using One of the major reasons marine reserves are not more the Deriso-Schnute biomass model [30], the biomass in patch i at common is that marine ecosystems are typically dominated by the beginning of year t+1 is single uses such as fishing [23]. Yet the amenity value of marine resources protected in marine reserves (via tourism) is often greater than the commodity value of these resources (via fishing), as the Bi,tz1 ~si,t Mi,t zrsi,t Mi,t { ð1Þ examples above show. In addition, there are other non-commod- rsi,t si,t{1 Mi,t{1 {rsi,t wk{1 Ri,t zwk Ri,tz1 ified goods and services provided by marine ecosystems that can be enhanced by marine reserves. Generally, there is a lack of the where Mt is the biomass in patch i after adult movement in year t, non-market data required to quantify the value of these goods and si,t is the annual survival of animals age k and older, wk is the services and therefore these benefits are often taken for granted average weight of an animal age k and older, wk{1 is the average [24]. weight of recruits, k is the age when the fish can reproduce,r is the By protecting coastal ecosystems such as mangroves, marshes Brody growth coefficient that controls the growth rate of and seagrass beds that are threatened by coastal development, individual fish, and Ri,t is recruitment in patch i in year t. The aquaculture, agriculture and wood production, marine reserves model accounts for two age classes, adults and recruits. All adults can play a significant role in protecting some of the most efficient for a given species have the same vulnerability to fishing pressure natural carbon sinks on the planet [25], enhancing coastal and reproduce. This model assumes that each species is protection from storms [26], and ensuring the supply of fish to homogeneous across all areas for all biological parameters. nearby fisheries [27]. For example, the value of one hectare of The simulations begin at equilibrium biomass (Bi,0 ), using a mangrove per year is up to $37,500 as a nursery for commercial specified unfished recruitment in each patch, Ri,0 such that fishes that will later recruit into adjacent fisheries [27], $18,000 as gross carbon credit revenue potential (assuming a carbon price of Ri,0 wk {rswk{1 $15/t CO2e) [28], and $10,821 as storm protection service [29], in Bi,0 ~ ð2Þ addition to the protection of human life on coastal areas prone to 1{s{rszrs2 tropical storms. In contrast, the net economic return of one hectare of mangrove converted into a shrimp farm in Thailand Annual survival st is the product of both natural survival s and was only up to $1220 per year in 1997–2004 [29]. the survival from fishing mortality. The harvest rate u is specified Despite the increasing amount of evidence of the benefits for both pre and post implementation of a no-take zone, for each provided by marine reserves, there are issues that have impeded patch. the creation of marine reserves as a tool that yields economic profitability. The major economic arguments against marine reserve creation are short-term loss of fishing catch and revenue si,t ~sð1{ui,t Þ ð3Þ because of the closure of a fraction of the fishing grounds, and displacement of fishing effort to unprotected areas. The latter has PLOS ONE | www.plosone.org 3 April 2013 | Volume 8 | Issue 4 | e58799 Marine Reserve Business Model Larval dispersal, recruitment, and adult calculate the total value divers place on dives, represented by the movement. The number of eggs produced each year is assumed consumer surplus (Fig. 1). We expect a1 ,0, reflecting the fact that to equal the spawning biomass at the beginning of each year. The additional dives are increasingly less valuable. We expect a2 .0, larvae are dispersed in a Gaussian fashion, so larvae do drift from reflecting the fact that a dive’s marginal value is positively one patch to another but the proportion that derive from the influenced by additional biomass in the reserve – importantly we source to any given location decreases with distance between the assume this effect is linear, which is likely to hold for modest sites. This does not explicitly model larval advection. The relative changes in biomass, but may not continue to hold for extremely proportion of fish moving from area i to area j are defined as large increases in biomass. While we focus on the biomass of key species, it is possible that diver demand would also depend on the ! diversity of fish. {di2 ,j pi,j ~exp ð4Þ An optimal fee per dive in year t (OPt) is calculated to maximize 2s2 L the tourism revenue in year t. Tourism revenue is defined as the product of the fee per dive and the number of dives in the reserve: where d is the distance between area i and area j. The model parameter sL defines the dispersal range for the species. The relative proportions are then normalized so that the total proportion of moving from area i to any area sum to one. The Dr,t Pt ~Dr,t (a0 za1 Dr,t za2 Br,t ) ð10Þ settlement of the eggs Ei,t in each patch is then calculated as . By taking the derivative of equation 10 with respect to Dr,t and X 100 setting the equation equal to zero, the number of dives that S i ,t ~ Ej ,t pj :i ð5Þ maximize the tourism revenue in year t is: j ~1 Adult movement is determined using the same Gaussian a0 za2 Br,t movement, with an adult movement parameter of sA . D r ,t ~ ð11Þ {2a1 Density dependent recruitment in each patch is calculated using a Beverton-Holt form [30] . The optimal fee per dive that maximizes tourism revenue is then 0:8Ri,0 hSi,t calculated by: Ri,t ~ ð6Þ 0:2Bi,0 ð1{hÞzðh{0:2ÞSi,t   where h is the steepness parameter for the species which is a0 za2 Br,t describes its productivity level. OPt ~a0 z za2 Br,t ð12Þ {2 Economic model . Fishing. The fishery catch (C) in patch i, year t, is the product of harvest rate, ui,t , and biomass in each patch and for each year. Example application To illustrate the dynamics of the bio-economic model, we 0 present a simulation based on the characteristics from the Medes Ci,t ~ui,t Bi,t ð7Þ Islands fishery in Spain. This case study builds from the bio- 0 economic analysis by Merino et al. [31] which focuses on long-run, where Bi,t is the biomass of the species after adult movement. or equilibrium, effects of reserve implementation. Because one of The fishery profit FVt in year t is given by: our main questions concerns the economic returns from reserves, X analyzing the inter-annual dynamics is crucial. Our goal is to FVt ~ (cCi,t {ci ui,t ) ð8Þ determine the time period for which the species recovery and i economic development of tourism surpass the short term loss in fishing grounds. This case study is provided to illustrate and where c is the price per gram for the species and ci is the cost per example of the short term dynamics under this model for a fishery unit effort to fish in area i. such as the Medes Islands. Tourism. Tourism values are often neglected in bioeconomic The Medes Islands Marine Reserve was created in 1983, and it analyses of marine reserves. We model the marginal value of includes a no-take zone of 51 ha, and partially-protected area of additional site visits (or ‘‘dives’’) as follows: 460 ha where seven local artisanal fishing vessels have exclusive access [31]. We use parameters based on data from this fishery Pt ~a0 za1 Dr,t za2 Br,t ð9Þ (Table 2) and from a long-term ecological monitoring of the reserve [32] to explore model predictions for this fishery upon where Dr,t is the number of dives in the reserve and a0 , a1 , and a2 implementation of a marine reserve. are parameters estimated for each location that the model is To simulate this reserve system, we use three harvest rates, one applied. Here we focus on economic well-being of divers for the no-take zone, one for the partial reserve and one for the themselves, and implicitly ignore further ancillary benefits arising area with no reserve. The relative size of these areas matches the from the multiplier effect of tourism revenue in the community. relative areas of the Medes Islands zones (1%, 12% and 87%). In Equation 9 can be used to calculate the number of dive-days these areas we simulate the biological dynamics of two represen- demanded for any given price and any given level of fish tative species and their change in biomass over time. We use the abundance by solving equation 9 for Dr,t . We can also use this to striped red mullet (Mullus surmuletus) to represent the species PLOS ONE | www.plosone.org 4 April 2013 | Volume 8 | Issue 4 | e58799 Marine Reserve Business Model Figure 1. Hypothetical illustration of equation 9 (the solid diagonal line). Revenue and consumer surplus can be calculated as areas under this line and change each year depending on the species biomass and number of dives. The dotted line illustrates equation 9 at higher biomass levels. doi:10.1371/journal.pone.0058799.g001 Table 2. Parameter values for the Medes Islands Marine Reserve example. Biological Parameters Species s wk wk-1 r Ri,0 sL sA h Mullus surmuletus 0.66 53.93 0 0.77 52000 2 1 0.75 Dicentrarchus labrax 0.9 384.9 0 0.85 6100 2 0.01 0.75 Fishery Parameters M. surmuletus D. labrax Zone u pre-reserve u post-reserve u pre-reserve u post-reserve No-take 0.75 0 0.2 0 Restricted zone 0.75 0.375 0.2 0.1 Open access 0.75 0.75 0.2 0.2 Economic parameters Fishery (Euros) c (J kg21) ci 9.97 9905 Tourism a0 a1 a2 Reserve fee/dive (J ) 9.6448 20.003 .00004 3.5 Parameter s is the annual natural survival rate, wk is the average weight of an animal age k and older, wk-1 is the average weight of recruits, r is the Brody growth coefficient, Ri,0 is unfished recruitment, u is the annual harvest rate, c is the price per gram for the species, ci is the cost per unit effort to fish in area i, and a0 , a1 , and a2 are location specific parameters for the tourism model. doi:10.1371/journal.pone.0058799.t002 PLOS ONE | www.plosone.org 5 April 2013 | Volume 8 | Issue 4 | e58799 Marine Reserve Business Model important to the fishery and European seabass (Dicentrarchus labrax) the reserve system, the fishing pressure is assumed to drop to zero to represent the species that divers are interested in seeing in the in the no-take zone, is reduced in half in the partially-protected water. area, and remains the same outside of the reserves. Estimates for We conducted a second simulation mirroring management fishing costs were based on personal communications with local changes that occurred at the Medes Islands Marine reserve. In fishers. Prices per kg of fish were based on prices for the red mullet 1990, the Catalan parliament passed a law that expanded the [31]. Estimates for a0 , a1 , and a2 were calculated to reflect the protection and established tools for more effective conservation number of divers each year in the marine reserve. management [33]. To prevent the deleterious impact of an The output of the model was remarkably accurate. When we excessive number of divers on the fragile benthic communities of capped diver numbers at the 1991 level, we obtained 63,000 dives the Medes Islands [34], the number of divers was reduced to a per year, with a revenue generated by diving fees of J 221,000 maximum of 450 per day. The number of diving centers was (Fig. 2c). The actual number of dives conducted in 2009, almost 20 regulated, and each diving center has a dive quota; for divers using years after the diving quotas had been established, was 67,000 their own boat there is a first-come first-serve system. These divers, whose diving fees produced a revenue of J 235,500 [33]. measures were made effective in 1991. Therefore we capped the number of dives in our model in 1991, using a fixed dive fee of J Discussion 3.5. An increasing number of studies show that the combined Results economic benefits of marine reserves (including fishing enhance- ment, tourism, and ecosystem services) outweigh the costs of The simulation of the Medes Islands marine reserve was run for creating and maintaining the reserves [31,37], although to date no 100 years before the implementation of the no-take and partial no- reserve has been created with a business plan taking this into take zones. The simulation is then run for another 100 years to account. It is worth noting that while improvements in fisheries show the long term effects of implementing the reserve system. may be obtained by other management methods than solely Results from the simulation show that there is a short term loss in creating a reserve (e.g.; [38]) it is less likely that the tourism fishery profit accompanied by a steady increase in the tourism benefits would be realized in this way. This is because the tourism value (Fig. 2a). The tourism value accounts for the fee per dive for benefits with regard to increased fish abundance and size are visitors as well as the consumer surplus, which represents the place-based rather than diffused across all areas where the fish additional amount that visitors would have been willing to pay for occur. Reserves capitalize on the location specific potential for those dives. The fee per dive is assumed to be the current diver activities such as diving or other non-extractive uses. access fee of J 3.5 per dive in the Medes Islands for each year of Our bio-economic model shows that fishing revenue increases the simulation. In this example, even if one only considers net after the creation of a reserve, and also that tourism revenue benefits (consumer surplus plus fishery value), the reserve more surpasses the revenues from fishing. It is worth noting that the total than doubles the value of the marine ecosystem, with more value value of the reserve is larger than the pre-reserve value within only arising from tourism than from fisheries. The total value of the five years of protection. This result is in agreement with data on reserve becomes greater than the pre-reserve value within five the rapid biological recovery of reserves [39] and short-term local years of protection. fisheries enhancement [13,21,40]. Therefore the typical concern As discussed above, there are additional values of the reserve about short-term revenue losses associated to reserve creation, that are not captured by this analysis. One obvious source is the especially for fishers, should be easily addressed with a proper multiplier effect of diver expenditures in the local community business plan that estimates revenue projections, accounts for (hotels, restaurants, car rentals, dive equipment rental, etc.) While costs, and identifies financing mechanisms. we have omitted these additional sources of value, including them In the Medes Islands Marine Reserve example, before the would only serve to further increase the benefit of the reserve (see creation of the reserve, only four diving centers took tourists to the Discussion for actual economic benefits of the Medes Islands islands, generating a revenue of about J 0.5 million. Presently, the Marine Reserve). increased abundance of marine life in the reserve supports a We also consider another simulation where the fee per dive is thriving tourism industry including diving centers, snorkeling, glass changed each year by calculating the optimal fee each year to bottom boats, and kayaks. The current diver access fee of J 3.5 maximize tourism revenue using equation 12. This simulation per dive (snorkelers, kayakers, and glass bottom boat tourists do shows the possibility of increasing the tourism value (Fig. 2b). not pay access fees) brings in J 234,500 per year, which covers Parameter values used in this example are listed in Table 2. Many half of the annual budget for the reserve [31,33]. However, If we of the biological parameters were calculated from other known add other services (hotels, restaurants) that grew in association with parameter values for these species [35]. The steepness, h, was the increase in number of divers, the marine reserve brings a assumed to be 0.75, which is approximately the modal for minimum of J 10 million annually to the local economy – and 200 steepness values for a range of species [36]. Initial recruitment full-time jobs [31,33]. Before the creation of the reserve there were values for red mullet (representing all fished species) were 21 registered artisanal fishing boats, relative to seven professional estimated using carrying capacity values from Merino et al. [31] boats operating today. The difference in the number of active and then determining the total carrying capacity from these fishers is due to retirements of ageing fishers, and a shift to more species that represent 5 percent of total catch [31]. Initial lucrative businesses such as lodging, restaurants, and tourism. recruitment for European seabass (representing species in dive Current fishing revenue exceeds J 0.2 million [31]. Although industry) were estimated using relative abundances between the there are no published statistics on the local fisheries economics, red mullet and European seabass in the no-take zone [32]. interviews with local fishers indicate that revenue before the Parameters for the fishery were chosen to illustrate a species that creation of the reserve was lower than presently. In addition, the is experiencing a fishing pressure beyond its maximum sustainable areas around the Medes Islands Marine Reserve attract more than yield (red mullet) and a reduced rate for nontargeted fish that are 455 recreational fishing boat visits per year, with an average caught as bycatch (European seabass). After the implementation of expenditure in fuel, gear and bait of J 800 per boat [41]. Payment PLOS ONE | www.plosone.org 6 April 2013 | Volume 8 | Issue 4 | e58799 Marine Reserve Business Model Figure 2. Example simulation based on the Medes Islands marine reserve. A) The reserve is implemented in year zero and the fishery profit and total value (fishery and tourism combined) show short term losses before long term gains. The tourism value increase monotonically over time after implementation of the reserve. B) Medes Islands example with optimal fee per dive calculated each year. C) Medes Islands example capping the number of dives as those in 1991, to simulate actual management changes. doi:10.1371/journal.pone.0058799.g002 for ecosystem services, such as the one afforded by the Other constraints may exist to reserve creation such as capital regeneration of the seagrass Posidonia oceanica beds in the reserve constraints and the ability of potential beneficiaries to coordinate could increase income in the reserve; these and other benefits with those fishers bearing the short-term costs. Essentially, could be added to the model. As our bio-economic model predicts, potentially profitable reserves may suffer from incomplete markets. the aggregate economic value of the Medes Islands Marine Our example from Medes suggests that even for fisheries alone, Reserve is larger than the costs, and suggests that other reserves in the reserve will ultimately have a positive effect. However, in many locations with similar tourism opportunities could be designed as cases, fishers, the current users might oppose reserve formation revenue and job creators. Our model provides a general even when models and data produce expectations of future profits. framework to estimate costs and benefits and plan consequently. The short-term losers may face capital constraints and may have Uncertainty of future benefits may be one of the larger barriers little reason to expect to share in future tourism benefits. Even to reserve formation. The simulation model, paired with local when future fishery benefits are credible, current fishing interests biological and economic data could reduce uncertainty regarding may not hold secure claims to those future benefits. long-run financial benefits of a potential marine reserve. The There are many potential mechanisms that might resolve tourism literature is rich with methodologies to estimate the price- capital and coordination constraints. In some cases, improved elasticity of demand. The model parameter a1 could be estimated legal structures guaranteeing current fishers’ shares in future in some cases. When decisions must be made quickly and data are benefits may suffice. In other cases, the creation of markets for lacking, literature estimates from similar locations may still provide conservation may be appropriate. Finally, external organizations useful information on a1 . In either case, information on divers may wish to speed the formation of reserves by offering a buy-out price sensitivity paired with the simulation model can give critical to reduce fishing effort in the fishing zone, or by financing the loss information on potential revenues from reserve user-fees. A second in fishery value during the time gap between reserve implemen- critical economic parameter, a2 , reflects divers preferences for tation and fishery recovery. Possible financing mechanisms include larger and greater numbers of fish. This parameter is not as widely private investments and public/private partnerships, some of estimated as price-elasticity but it is possible to estimate divers’ which have proven successful in other social initiatives and businesses. In addition to facilitating the transition from open willingness-to-pay for increases in fish density and size [42]. access to a system with a fraction of the fishing grounds closed as PLOS ONE | www.plosone.org 7 April 2013 | Volume 8 | Issue 4 | e58799 Marine Reserve Business Model reserves, these mechanisms could cover the costs of creation and individual transferable quotas) [46,47,48] and co-designing marine management of reserves, making them self-sustaining. reserves with other spatial management measures can further Metrics for success will be critical for long-run benefits to be increase benefits [49]. In any case, a business approach could help realized. We cannot conclude that a reserve is failing only because replicate the success stories in a decentralized way that is not it is not enhancing the catch of one or more species around it (e.g., constrained by limited human and financial resources from [43]). That may be simply due to excessive fishing capacity/effort governments and conservation organizations. (regardless of the closure of a fraction of the fishing grounds), and the reserve may be too small or located in a sub-optimal location. Acknowledgments Furthermore, aggregate benefits afforded by protection may be much greater than the putative loss of fisheries yield. For instance, We are grateful to S. Case, J. De Bourbon Parme, M. Fiorese, J. Garrett- a fishery targeting a spawning aggregation of large predatory reef Cox, J. Jacquet, Y. Jarrar, B. Jenks, M. Jorge, S. Lindblad, L. Linden, A. Loesekrug-Pietri, P. McWhinney, O. Oullier, P. Patil, J. Plunkett, K. fishes will yield lower catches right after the spawning grounds are Rechberger, L. Schlesinger, N. Schwab, D. Shapiro, and the Young Global protected. However, fishing spawning aggregations universally Leaders’ Fish Banks Task Force for discussions and suggestions that greatly leads to collapse of the aggregations, the populations of the species, improved previous versions of this manuscript. and the fisheries they support [44]; whereas the increase in value of the aggregation site through ecotourism and replenishment of Author Contributions adjacent fishing grounds will far offset the short term loss of fishing profit [45]. It is thus essential that, for evaluating the efficacy of a Conceived and designed the experiments: ES CC GH KK AAR RS. marine reserve, the economic dynamics around the reserve are Performed the experiments: ES CC DD JHM. Analyzed the data: ES CC DD JHM. Wrote the paper: ES CC DD GH KK JHM AAR RS. compared to those in similar areas without reserves. The economic benefits of marine reserves may be enhanced by additional management around their borders (e.g., TURFs, References 1. Kelleher G (1999) Guidelines for Marine Protected Areas. IUCN. Gland, 21. Roberts CM, Bohnsack JA, Gell FR, Hawkins JP, Goodridge R (2001) Effects of Switzerland. marine reserves on adjacent fisheries. Science 294: 1920–1923. 2. Badalamenti F, Ramos AA, Voultsiadou E, Sanchez Lizaso JL, D’Anna G, et al. 22. Sala E, Knowlton N (2006) Global marine biodiversity trends. Annual Review of (2000) Cultural and socio-economic impacts of Mediterranean marine protected Environment and Resources 31: 93–122. areas. Environmental Conservation 27: 110–125. 23. Craig R (2007) Valuing Coastal and Ocean Ecosystem Services: The Paradox of 3. Dayton PK, Sala E, Tegner MJ, Thrush S (2000) Marine Protected Areas: parks, Scarcity for Marine Resources Commodities and the Potential Role of Lifestyle baselines and fishery enhancement. Bulletin of Marine Science 66: 617–634. Value Competition. Journal of Land Use and Environmental Law 22. 4. Lester SE, Halpern BS, Grorud-Colvert K, Lubchenco J, Ruttenberg BI, et al. 24. McClanahan TR (2010) Effects of Fisheries Closures and Gear Restrictions on (2009) Biological effects within no-take marine reserves: a global synthesis. Fishing Income in a Kenyan Coral Reef. Conservation Biology 24: 1519–1528. Marine Ecology Progress Series 384: 33–46. 25. Laffoley D, Grimsditch G (2009) The management of natural coastal carbon 5. Worm B, Barbier EB, Beaumont N, Duffy JE, Folke C, et al. (2006) Impacts of sinks. Gland, Switzerland: IUCN. 53 p. biodiversity loss on ocean ecosystem services. Science 314: 787–790. 26. Barbier E, al e (2008) Coastal ecosystem-based management with nonlinear 6. Guidetti P, Sala E (2007) Community-wide effects of marine reserves in the ecological functions and values. Science 319: 321–323. Mediterranean Sea. Marine Ecology Progress Series 335: 43–56. 27. Aburto-Oropeza O, Ezcurra E, Danemann G, Valdez Vc, Murray J, et al. 7. Micheli F, Halpern BS, Botsford LW, Warner RR (2004) Trajectories and (2008) Mangroves in the Gulf of California increase fishery yields. Proceedings of correlates of community change in no-take marine reserves. Ecological the National Academy of Sciences 105: 10456–10459. Applications 14: 1709–1723. 28. Murray BC, Pendleton L, Jenkins WA, Sifleet S (2011) Green Payments for Blue 8. Russ G, Alcala A (2004) Marine reserves: long-term protection is required for Carbon: Economic Incentives for Protecting Threatened Coastal Habitats. full recovery of predatory fish populations. Oecologia 138: 622–627. Nicholas Institute for Environmental Policy Solutions Report NI R 11-04. 9. Bascompte J, Melian CJ, Sala E (2005) Interaction strength combinations and 29. Barbier E (2007) Valuing ecosystem services as productive inputs. Economic the overfishing of a marine food web. Proceedings of the National Academy of Policy January 2007: 177–229. Sciences of the United States of America 102: 5443–5447. 30. Quinn II T, Deriso R (1999) Quantitative Fish Dynamics. New York: Oxford University Press. 10. Paddack MJ, Estes JA (2000) Kelp forest fish populations in marine reserves and 31. Merino G, Maynou F, Boncoeur J (2009) Bioeconomic model for a three-zone adjacent exploited areas of Central California. Ecological Applications 10: 855– Marine Protected Area: a case study of Medes Islands (northwest Mediterra- 870. nean). ICES Journal of Marine Science: Journal du Conseil 66: 147–154. 11. Willis TJ, Millar RB, Babcock RC (2003) Protection of exploited fish in 32. Ballesteros E, Garcia-Rubies A, Mariani S, Coma R, Diaz D, et al. (2008) temperate regions: high density and biomass of snapper Pagrus auratus (Sparidae) Monitoring of the Marine Protected Areas of Cap de Creus and Medes Islands. in northern New Zealand marine reserves. Journal of Applied Ecology 40: 214– Technical Report to the Catalan Government, Departament de Medi Ambient i 227. Habitatge. 80 pp. 12. Halpern BS, Lester SE, Kellner JB (2009) Spillover from marine reserves and the 33. Capella J (2010) The positive impact of a Protected Area on a mature tourist replenishment of fished stocks. Environmental Conservation 36: 268–276. destination. The case of Medes Islands Marine Reserve – L’Estartit (Spain). 13. Gell FR, Roberts CM (2003) Benefits beyond boundaries: the fishery effects of DECABA Technical Report to the Medes Islands Marine Reserve Management marine reserves. Trends in Ecology & Evolution 18: 448–455. Authority. 14. Jones PJS (2008) Fishing industry and related perspectives on the issues raised by 34. Garrabou J, Sala E, Arcas A, Zabala M (1998) The impact of diving on rocky no-take marine protected area proposals. Marine Policy 32: 749–758. sublittoral communities: a case study of a Mediterranean bryozoan population. 15. Sumaila UR, Armstrong CW (2006) Distributional and efficiency effects of Conservation Biology 12: 302–312. marine protected areas: A study of the Northeast Atlantic cod fishery. Land 35. Froese R, Pauly D (2012) FishBase. World Wide Web electronic publication. Economics 82: 321–332. www.fishbase.org. 16. Green E, Donnelly R (2003) Recreational scuba diving in Caribbean marine 36. NMFS (2009) Steepness of spawner-recruit relationships in reef fishes of the protected areas: Do the users pay? Ambio 32: 140–144. southeastern U.S.: A prior distribution for possible us in stock assessment. 17. Burke L, Maidens J (2004) Reefs at Risk in the Caribbean. Washington, DC: SEDAR19-DW-06. World Resources Institute. 37. McCook LJ, Ayling T, Cappo M, Choat JH, Evans RD, et al. (2010) Adaptive 18. Gon ˜ i R, Badalamenti F, Tupper M (2011) Effects of marine protected areas on management of the Great Barrier Reef: A globally significant demonstration of local fisheries: evidence from empirical studies. In: Claudet J, editor. Marine the benefits of networks of marine reserves. Proceedings of the National Protected Areas: A multidisciplinary approach. Cambridge: Cambridge Academy of Sciences 107: 18278–18285. University Press. pp. 72–98. 38. Worm B, Hilborn R, Baum JK, Branch TA, Collie JS, et al. (2009) Rebuilding 19. Russ GR, Alcala AC, Maypa AP, Calumpong HP, White AT (2004) Marine Global Fisheries. Science 325: 578–585. reserve benefits local fisheries. Ecological Applications 14: 597–606. 39. Halpern BS, Warner RR (2002) Marine reserves have rapid and lasting effects. 20. Cooke SJ, Danylchuk AJ, Danylchuk SE, Suski CD, Goldberg TL (2006) Is Ecology Letters 5: 361–367. catch-and-release recreational angling compatible with no-take marine protected 40. Tawake A, Parks J, Radikedike P, Aalbersberg B, Vuki V, et al. (2001) areas? Ocean & Coastal Management 49: 342–354. Harvesting Clams and Data: Involving local communities in monitoring can lead PLOS ONE | www.plosone.org 8 April 2013 | Volume 8 | Issue 4 | e58799 Marine Reserve Business Model to conservation success in all sorts of unanticipated ways: A case in Fiji. 49. Rassweilier A, Costello C, Siegel D (2012) Marine protected areas and the value Conservation in Practice 2: 32–35. of spatially optimized fishery management. Proceedings of the National 41. Sacanell M (2012) Study on recreational fishing in the Medes Islands marine Academy of Sciences of the USA In press. protected area. Technical Report to the Medes Islands Marine Reserve 50. Goni R, Hilborn R, Diaz D, Mallol S, Adlerstein S (2010) Net contribution of Management Authority. 52 pp. spillover from a marine reserve to fishery catches. Marine Ecology Progress 42. Weilgus J, Gerber LR, Sala E, Bennett J (2009) Including risk in stated- Series 400: 233–243. preference economic valuations: Experiments on choices for marine recreation. 51. Galal N, Ormond RFG, Hassan O (2002) Effect of a network of no-take reserves Journal of Environmental Management 90: 3401–3409. in increasing catch per unit effort and stocks of exploited reef fish at Nabq, South 43. Smith MD, Zhang J, Coleman F (2006) Effectiveness of marine reserves for Sinai, Egypt. Marine and Freshwater Research 53: 199–205. large-scale fisheries management. Canadian Journal of Fisheries and Aquatic 52. Murawski SA, Wigley SE, Fogarty MJ, Rago PJ, Mountain DG (2005) Effort Sciences 63: 153–164. distribution and catch patterns adjacent to temperate MPAs. ICES Journal of 44. Sadovy Y, Domeier M (2005) Are aggregation-fisheries sustainable? Reef fish Marine Science: Journal du Conseil 62: 1150–1167. fisheries as a case study. Coral Reefs 24: 254–262. 53. Aburto-Oropeza O, Erisman B, Galland GR, Mascaren ˜ as-Osorio I, Sala E, et 45. Sala E, Ballesteros E, Starr RM (2001) Rapid decline of Nassau grouper al. (2011) Large Recovery of Fish Biomass in a No-Take Marine Reserve. PLoS spawning aggregations in Belize: Fishery management and conservation needs. ONE 6: e23601. Fisheries 26: 23–30. 54. Buchan K, Framhein R, Fernandes L (1997) An economic and social study of 46. White C, Costello C (2010) Matching spatial property rights fisheries with scales the Saba Marine Park, Saba, Netherlands Antilles. CANARI Technical Report of fish dispersal. Ecological Applications 21: 350–362. 47. Costello C, Kaffine DT (2010) Marine protected areas in spatial property-rights No. 262:37 pp. fisheries. Australian Journal of Agricultural and Resource Economics 54: 321– 55. Hicks CC, McClanahan TR, Cinner JE, J.M H (2009) Trade- offs in values 341. assigned to ecological goods and services associated with different coral reef 48. Gaines SD, Lester SE, Grorud-Colvert K, Costello C, Pollnac R (2010) Evolving management strategies. Ecology and Society 14: http://www.ecologyandsociety. science of marine reserves: New developments and emerging research frontiers. org/vol14/iss11/art10/. Proceedings of the National Academy of Sciences 107: 18251–18255. PLOS ONE | www.plosone.org 9 April 2013 | Volume 8 | Issue 4 | e58799