Endangered Species, Ecosystem Integrity, and Human Livelihoods
2016; Wiley; Linguagem: Inglês
10.1111/conl.12317
ISSN1755-263X
AutoresOctavio Aburto‐Oropeza, Catalina López‐Sagástegui, Marcia Moreno‐Báez, Ismael Mascareñas‐Osorio, Victoria Jiménez‐Esquivel, Andrew F. Johnson, Brad Erisman,
Tópico(s)Aquatic Ecosystems and Biodiversity
ResumoConservation LettersVolume 11, Issue 1 e12358 POLICY PERSPECTIVEOpen Access Endangered Species, Ecosystem Integrity, and Human Livelihoods Octavio Aburto-Oropeza, Corresponding Author Octavio Aburto-Oropeza maburto@ucsd.edu Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA, 92093 USACorrespondence Octavio Aburto-Oropeza, Gulf of California Marine Program, Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA 92093, USA. Tel: (858) 822–3765; fax: (858) 822–3310. E-mail: maburto@ucsd.eduSearch for more papers by this authorCatalina López-Sagástegui, Catalina López-Sagástegui UC MEXUS, University of California Riverside, Riverside, CA, 92521 USASearch for more papers by this authorMarcia Moreno-Báez, Marcia Moreno-Báez Centro para la Biodiversidad Marina y la Conservación, La Paz, 23090 MexicoSearch for more papers by this authorIsmael Mascareñas-Osorio, Ismael Mascareñas-Osorio Centro para la Biodiversidad Marina y la Conservación, La Paz, 23090 MexicoSearch for more papers by this authorVictoria Jiménez-Esquivel, Victoria Jiménez-Esquivel Centro para la Biodiversidad Marina y la Conservación, La Paz, 23090 MexicoSearch for more papers by this authorAndrew Frederick Johnson, Andrew Frederick Johnson Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA, 92093 USASearch for more papers by this authorBrad Erisman, Brad Erisman University of Texas at Austin, Marine Science Institute, Port Aransas, TX, 78373-1015 USASearch for more papers by this author Octavio Aburto-Oropeza, Corresponding Author Octavio Aburto-Oropeza maburto@ucsd.edu Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA, 92093 USACorrespondence Octavio Aburto-Oropeza, Gulf of California Marine Program, Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA 92093, USA. Tel: (858) 822–3765; fax: (858) 822–3310. E-mail: maburto@ucsd.eduSearch for more papers by this authorCatalina López-Sagástegui, Catalina López-Sagástegui UC MEXUS, University of California Riverside, Riverside, CA, 92521 USASearch for more papers by this authorMarcia Moreno-Báez, Marcia Moreno-Báez Centro para la Biodiversidad Marina y la Conservación, La Paz, 23090 MexicoSearch for more papers by this authorIsmael Mascareñas-Osorio, Ismael Mascareñas-Osorio Centro para la Biodiversidad Marina y la Conservación, La Paz, 23090 MexicoSearch for more papers by this authorVictoria Jiménez-Esquivel, Victoria Jiménez-Esquivel Centro para la Biodiversidad Marina y la Conservación, La Paz, 23090 MexicoSearch for more papers by this authorAndrew Frederick Johnson, Andrew Frederick Johnson Marine Biology Research Division, Scripps Institution of Oceanography, La Jolla, CA, 92093 USASearch for more papers by this authorBrad Erisman, Brad Erisman University of Texas at Austin, Marine Science Institute, Port Aransas, TX, 78373-1015 USASearch for more papers by this author First published: 22 February 2017 https://doi.org/10.1111/conl.12358Citations: 22 Correction added on 04/25/2017, after initial online publication. A duplicate of this article was published under the DOI 10:1111/conl.12317. This duplicate has now been deleted and its DOI redirected to this version of the article. AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract If efforts to conserve endangered species lack long-term visions and neglect the human dimensions, conservation success will be questionable. Exclusion of stakeholders in decisions can lead to mistrust and polarization of groups. The story of the vaquita marina (Phocoena sinus) in the Upper Gulf of California provides a unique opportunity to discuss this paradigm. A proposed gear-switch in the regional fisheries addresses the bycatch issue that threatens the vaquita but neglects livelihoods, the traditions and heritage of the community, and the ecological integrity of the area, and it increases dependence on fishing subsidies. We estimate that it will cost an additional US $8.5 million (2/3 of the net revenue produced by gillnets and 30% more in fuel consumption) if local revenues are to be maintained at pregear-switch levels. Additionally, suggested new trawl gears caught 2.7 times more unusable (therefore discarded) bycatch than gillnets, which included invertebrates and small juvenile fishes of economically valuable and endangered species. Our results show that the proposed gear switch intervention can be considered another "quick-fix" intervention in the history of the vaquita conservation agenda that urgently needs long-term goals that adequately incorporate ecological, economic, and human well-being. Introduction What are the ecological and social impacts of efforts to conserve charismatic species that face the imminent threat of extinction? This is one of the most important questions in environmental conservation practice and policy (Sutherland et al. 2009), and the answer has significant implications for global conservation management. Existing conservation model frameworks (Bulte & Horan 2003; Barrett et al. 2011; McNally et al. 2011) often identify the relationships between ecosystem services and the importance of including stakeholders and authorities in the planning processes of protecting and/or exploiting these services (Lynam et al. 2007; Bauch et al. 2014; Rassweiler et al. 2014). It is, however, still challenging to use single-species strategies to find a balance between restoring their populations, protecting ecosystem integrity, and maintaining human well-being in the region where the species exists. When resource extraction combines with bad management, it can drive a situation of radical conservation actions, which is nowadays a somewhat common paradigm in conservation texts (Gjertsen & Niesten 2010; Walston et al. 2010; Duffy 2014; Duffy et al. 2015), and makes future collaborations between extractive and conservation sectors increasingly difficult. The story of the critically endangered vaquita (Phocoena sinus) offers the extraordinary opportunity to discuss this paradigm of radical conservation action in order to save a species at risk. The vaquita is endemic to the Upper Gulf of California (UGC) and it is now the world's most endangered cetacean (Rojas-Bracho et al. 2006). The history of vaquita conservation is long, complex, and began following reported bycatches in the totoaba (Totoaba macdonaldi) fishery in the early 1960s (Vidal 1995) once the vaquita was first described (Norris & McFarland 1958). After the official closure of the totoaba fishery, the focus of vaquita bycatch moved to the UGC's shrimp gillnetters (D'Agrosa et al. 2000) and, in 1993 the UGC and Colorado River Delta Biosphere Reserve was established (McGuire & Valdez-Gardea 1997; Rojas-Bracho et al. 2006; Morell 2008). Predictions that only 59 vaquita are left (CIRVA 2016) and the continuing declines (CIRVA 2015) have increased pressure on the Mexican government that passed a law in 2013 to replace all shrimp gillnets with small trawling nets by the end of 2016. Government reports suggest that these trawls are 100% vaquita-safe (INAPESCA 2014), while other reports demonstrate that fish and invertebrate bycatch ratios are more than is considered legal in the biosphere reserve (7:1 kg bycatch to shrimp) (Calderon-Aguilera 2011; Perez-Valencia et al. 2012). Continued public and conservation-sector pressure have more recently lead to the announcement of a 2-year emergency gillnet ban throughout the vaquita's distribution, which began in May 2015 (DOF 2015). Additional strategies include: (1) buy-out and fishing gear switch-out programs, which have received around 40 million dollars (US) in the last 7 years and (2) increases in the budget for enforcement activities (Rojas-Bracho et al. 2006; Barlow et al. 2010). The impact of these management actions has polarized opinion among local communities and created a large rift between the fishing and conservation sectors (McGuire & Valdez-Gardea 1997; Barlow et al. 2010; Rodríguez-Quiroz & Aragón-Noriega 2013). This divide has been worsened by the exclusion of fishers from the formation of the new conservation measures, including the design of the new government trawls and gear tests, while expecting collaboration for data collections using this gear. The majority of knowledge used in the management and conservation of the UGC has come from western science and has had a disproportionate effect on social, cultural, and economic structures locally (Klein et al. 2015; Cisneros-Montemayor & Vincent 2016), wasting significant, useful information that the fishers' knowledge can provide for the design of management decisions (Hilborn 2007). Here, we present the quantitative results of fishing gear tests and discuss how a lack of collaboration between conservation and extractive sectors reduces the possibility of successful future management scenarios. We demonstrate how increasing conservation pressures with a lack of collaboration between sectors can repeatedly lead to last minute efforts, which do not address the wider issues associated with saving endangered species. Challenges to maintain fishery profits Following the widespread opposition by fishers to the long-term phase-out of gillnets, a period of gear testing was ordered by the Mexican government to estimate compensation costs. From August 18th to September 18th 2013, the Mexican Fisheries Institute (INAPESCA) conducted experimental gear tests as described in the Supplementary Information. Together with data from a cooperative research program, we described summary statistics for the three fishing gears tested in the experiment (fishing trips, n = 326) and present estimates of revenue using current ex-vessel prices of landed catch and fishery costs using fuel consumption rates and fuel prices. Additionally, we estimated the overall value of the fishery and the cost to the government in terms of subsidy provision as a means for understanding the potential impacts on livelihoods at a regional scale. Since we aim to show the risk of implementing public policies with limited data that forego a robust economic analysis of fishing gears, it is important to carefully interpret our absolute values of subsidies needed to maintain fishery profits based on the limitations of the experimental design. We found significant differences in the amount of shrimp caught by the different fishing gears (Figure 1). Gillnets caught an average of 3.2 times more shrimp than the RSINP trawlers (ANOVA P < 0.001), which caught a similar amount to the modified trawler nets (P = 0.83) (Figure 1a). Gillnets covered an area 1.89 times larger than both trawler types (P < 0.001) and the biomass of shrimp per unit area was significantly higher (0.9 kg vs. 0.4 shrimp per km2) for gillnets than the trawlers (P < 0.001) (Figure 1b). Gillnets caught more incidental (usable) bycatch (total kg) in the form of adult marketable fish than the RSINP trawlers (P < 0.01). In contrast, both kinds of trawls caught 2.7 times more unusable (therefore discarded) bycatch (P < 0.001) that included small juvenile fishes (< 10 cm) and juvenile invertebrates (Figure 1c). Both types of trawlers spent almost 30% more fuel per working trip (P < 0.001) than trips fishing with gillnets (Figure 1d). Figure 1Open in figure viewerPowerPoint Average values (± SEM) of variables selected in the fishing gear-testing period in order to estimate compensation costs to cover economic losses incurred by the use of trawling nets in place of gillnets in the Upper Gulf of California shrimp fishery. Bars that share a letter within each plot are not significantly different from one another. In the bycatch figure (c), solid bars represent usable bycatch, hatched bars represent discarded bycatch, and significance for each is marked with plain versus underlined letters. We estimate that in previous shrimp fishing seasons (2011–'12, 2012–'13), each boat caught an average of 27.4 kg of shrimp per trip (± 0.7 SEM, n = 1,221 monitored fishing trips), a higher value than the 18.5 kg average obtained in the trips during the seasons from 1995 to 2002 (Perez-Arvizu et al. 2009). Based on an estimate of 645 boats with shrimp fishing permits in both communities, an average ex-vessel price of US $12.41 (± 0.09, n = 1,128) per kg of shrimp and an average of 100 trips per boat per season (Perez-Valencia et al. 2012), the gross revenue of this fishery inside the reserve is approximately US $21.78 million dollars. Taking into account the capture efficiency of the RSINP trawlers, and with 50% of the revenue from gillnets used for the costs of each trip, we estimate that the Mexican government would have to subsidize two thirds of the net revenue (US $10.89 million × 0.66) from the shrimp fishery (close to US $7.20 million dollars annually), to allow fishers to make the same earnings as they did previous to the proposed gear switch. The cost of fuel needed to operate the entire shrimp fleet using gillnets during the fishing season equates to approximately US $4.45 million dollars (calculated based on #boats × #trips × average fuel used per trip × price per liter). Since the average fuel consumption of the RSINP trawlers is 30% higher per trip, the Mexican government would need to subsidize the fishery an additional US $1.33 million dollars annually, assuming the fishers only fish with the RSINP trawls three times per day. The need for a new paradigm The behavior of "quick-fix"-type management, in which longer term environmental degradation is not addressed, vast sums of money are invested, and social well-being left unconsidered is by no means sustainable. Short-term solutions that have developed in response to a crisis situation are particularly ineffective for a species whose life-history spans decades, such as the vaquita. Our results show that the proposed gear switch intervention does not provide the fishers with a viable future livelihood, compared to their historic fishing activities. More importantly, there is evidence that the widespread implementation of small trawls stands to threaten the integrity of the entire marine ecosystem in the same manner as trawl-based fisheries elsewhere in the Gulf of California and the world (Kaiser 2008; Puig et al. 2012). Successful management, on the other hand, should be focused on longer term goals with minimal or zero governmental subsidies (Sumaila & Pauly 2007), and no additional risk to the integrity of local ecosystems. With increasing pressure from environmental groups, conservation has been favored over the fishery and local economies in the UGC; which overall represents a shortsighted conservation approach that has characterized the history of the region. The combination of conservation versus fishery extremes, in conjunction with a consistent lack of collaboration between such groups, has led to the current difficulties in which management options have been significantly reduced. Local fisheries and livelihoods have been jeopardized and the situation of restoring the vaquita population is questionable due to the likelihood of noncompliance following a reliance on subsidies. This has exacerbated illegal fishing within local protected areas and outside of official fishing seasons (Platt 2014), as well as incentivized the continued illegal fishing of the totoaba (Haro Cordero 2016) that, through bycatch, negates the current gillnet ban and continues to threaten the vaquita's survival. Below, we first discuss the fisheries-economic, single short-term approach and the outcomes that have resulted so far. We then discuss some ideas related to longer term visions involving the education and well-being of locals, which the authors believe is necessary to break the vicious cycle. The short and narrow vision The 2-year gillnet ban may benefit the conservation of the vaquita for 2 years, but there is no guarantee that it will not revert back to the preban "norm" of continued bycatch. If the return to "normal" fishing happens, it is unlikely that any benefit gained in the 2-year intervention period will have had noticeable effects on the vaquita's population levels. Similar is true for the fisher's livelihoods. Current subsidies may buffer the effects of lost revenues in the short term, but there is no guarantee of continued government payments. The environmental impacts of the switch to trawl gear have also been left unconsidered. For example, in El Golfo de Santa Clara, the 255 trips by 49 boats using both kinds of trawlers during the gear-testing period trawled an area of 2,819 km2 that corresponds to 30% of the biosphere reserve's total area (Figure 2). Considering that there are more than 600 boats with shrimp permits (Erisman et al. 2015), the volume of discarded bycatch and the potential negative effects of such activities on juvenile fishes, invertebrate communities, and bottom habitats are likely to be substantial enough to disrupt the integrity of the whole ecosystem (Lewison et al. 2004; Hinz et al. 2009). This deserves important consideration as the UGC is home to the breeding and nursery grounds of species listed as critically endangered (P. sinus and T. macdonaldi) and numerous other endemic species (e.g., Cynoscion othonopterus and Scomberomorus concolor) that are highly vulnerable and/or valuable to the local economies (Erisman et al. 2015). For example, bycatch of juvenile totoaba was identified a causal factor in the collapse of the fishery and the species (Cisneros-Mata et al. 1997). The recovery of the totoaba is already threatened by widespread poaching of adults, and the potential impacts of juvenile bycatch by this new trawl fishery have not been assessed. Likewise, large volumes of juvenile corvinas were reported in the first experimental tests of the new trawls (INAPESCA 2009). Figure 2Open in figure viewerPowerPoint Map of the Upper Gulf of California demarcating the areas trawled by fishers during government gear testing in 2013. (a) Shows the fished area during the first day of testing (137 km2) and (b) the total area fished after 26 days of testing (2,819 km2). UGCCRD BR, Upper Gulf of California and Colorado River Delta Biosphere Reserve; GSC, Golfo de Santa Clara. Legend denotes the degree of use (number of trawl passes). Even while experimental gear testing of trawls has been conducted numerous times since 2008 as a means for improving the efficiency and reducing ecological impacts (INAPESCA 2010; INAPESCA 2014), and these tests have involved both fishers with and without experience in using such gear, results of such tests and others that have monitored the environmental impacts of regional fishing activities (Calderon-Aguilera 2011; Perez-Valencia et al. 2012; this study) continue to show high bycatch rates of invertebrates and fishes of commercial (corvina) and conservation (totoaba) importance compared to gillnets. It is unlikely that bycatch rates were influenced by the experiment design, since these fauna are present in the entire region throughout the year, trips during trawl experiments were randomly assigned (spatially), and the boat operator could not influence the performance of the trawler once it was working the sea bottom. Nevertheless, even if our results and those of other studies represent a worst-case scenario in terms of environmental impacts, they speak to the need for a comprehensive assessment of the distribution and importance of key benthic habitats in the Upper Gulf and the impacts of the trawls on habitat quality and community composition. Moreover, if we consider that most fishers are inexperienced with using trawls, and that bycatch rates are high among inexperienced operators, the short-term impacts on benthic fishes (e.g., juvenile totoaba, bigeye croaker, and corvinas) and critical habitats that result from a gear-switch in the near future are likely to fall within the levels of our study. A long history of investment in the fisheries with little consideration for local ecology has favored extraction over conservation in Mexico (Cisneros-Mata 2010). Our estimations of the potential subsidy expenditure required for the use of the RSINP trawls instead of gillnets are conservative (≈ US $8.5 million in subsidies per year; 2/3 of the net revenue plus 30% of fuel consumption), since the gear switch will also bring changes in fisher training and increased industrialization of the fishing sector in terms of engine use and fuel efficiency (e.g., a move to diesel engines). Although the trawlers have not been tested during the formal shrimp-fishing season (late September to late February), the authors consider that the performance of the trawlers would not change significantly if tested during the fishing season, since the shrimp ban is to protect the species at the moment of reproduction, not because the shrimp is only present outside of the time that the experiment was undertaken (August) (DOF 2013). Our economic estimations are all costs additional to the already planned US $72 million for the emergency gillnet ban of 2015–2017 (Malkin 2015), which represents the earnings of the active fishers in the UGC over a 2-year period, as well as the costs of surveillance during the gillnet ban. It is also noteworthy that the UGC fishing industry suffers from a monopsony market situation, in which all sellers interact with one or very few buyers, reducing the options for individual fishers to obtain higher market values or the option of value adding before sale (Valdez-Gardea 2007). The authors believe that such a situation has evolved due to the UGC's remote location and the lack of external investment and internal training of the fishing community. The monopsony could be addressed in a number of ways, including new investment to bring seafood purchase and/or packaging companies to the area and by training fishers to add value to their own catches. Without reducing or eliminating the monopsony, market-price strategies proposed for the region and within the vaquita agenda will continue to fail or generate benefits to a limited number of stakeholders (Klein et al. 2015). The holistic and long-term vision To date, no long-term goals have been designed for the UGC and the few collaborative efforts between conservation and extractive sectors have had disappointing results. Conservation policies must consider the extractive sector (in this case, fishers) as partners rather than opponents, to increase compliance and the probability of success (Reed 2008; Leslie et al. 2015). The vaquita conservation agenda should move toward restoring balance between the different groups involved, and immediate attention paid outside of fishery subsidies and high impact fishing gear switches is needed. It is necessary for all groups involved to acknowledge that the root of the problem lies in the lack of support for communities that have been built on an extractive industry, which is detrimental to an endemic species. It is necessary to push for an urgent agreement between the conservation and fishery sectors to resolve fundamental community needs. These communities face serious needs for basic infrastructure in order to develop other kinds of economies beyond fishing (Avila-Forcada et al. 2012). With very few options for alternative livelihoods, fishing recruits men as young as middle school level, creating a cycle where the scenario of once a fisher always a fisher occurs. Government investment in better education and training in the UGC would help increase livelihood options (Rodríguez-Quiroz & Aragón-Noriega 2013), such as sports fishing tourism or other service industry activities that would potentially help increase the environmental awareness and the promotion of longer term visions in the region. The last minute management decision of fishery closures and altered fishing gear types in the UGC only addresses an immediate issue (bycatch of the vaquita) and therefore overall, fails twofold. It disregards the long-term sustainable use of the wider ecosystem by not accounting for the negative impacts of using destructive trawl practices. It also neglects approaches that include local fishers and their knowledge that would likely consider longer term, larger scale sustainability of the UGC system. For example, since the establishment of the reserve, fishing effort (number of fishers and boats) has not decreased but remained stable; something that fishers have agreed needs to be addressed, especially considering the unknown levels of illegal fishing. This, however, has not been a priority for the government nor the conservation sector, and has been left unaddressed. The best-case scenario is always one in which the extractive and conservation sectors involved collaborate toward a commonly shared goal (Goodrich et al. 2011; Barner et al. 2015; Finkbeiner & Basurto 2015). Reductions of fishing effort can be one of these goals and is an indicator which is easy to measure in the long-term. If social well-being is given priority, the authors believe that longer term sustainable local fisheries are more likely to develop which, in turn will help develop marine stewardship in the fishers and the community (Cisneros-Montemayor & Vincent 2016). Curbing vicious cycles in which one resource is depleted after another should be a primary goal of fisheries managers in the UGC. Fishers need inclusion from the start in the design of new conservation initiatives. Members of the fishing sector should be contributing with knowledge, ideas, and other means of support; participation in public policy should be equal across all sectors. Solely informing a fisher of a new rule, even though it affects his livelihood, should not be expected to produce friendly relations. Previous inclusions in enforcement activities by the government relating to the vaquita refuge (Environmental Investigation Agency 2016) likely failed due to discontent that already arose from the exclusion of fishers early in the UGC's conservation history. Initiatives that focus on biodiversity conservation and threatened species rely on top-down management approaches. Most of the time, these approaches are incapable of engaging different sectors of society, especially in communities from developing countries (Rodriguez et al. 2007). Subsidies often help sustain extractive activities, the result of which commonly opposes conservation agendas. This study highlights that the government-proposed gear switch for vaquita conservation will likely necessitate more subsidies to maintain fishing livelihoods as they were before the gillnet ban. This will perpetuate overcapacity, fuel conflict between the conservation and fisheries sector and ultimately, reduce the likelihood of conservation success, for what is already a mammal population on the brink of extinction. Ignoring the players in conservation-extraction scenarios, denying the existence of the tightly coupled social–economic–ecological relationships, or ignoring opportunities to increase cooperation (Sawchuk et al. 2015) will perpetuate the design of unsuccessful, top-down management strategies, which often put the integrity of the ecosystems at further risk (Ban et al. 2013). Acknowledgments We thank C. Tirado, R. Franco, and all the fishers from the UGC who helped collected data; A. Espinoza, Y. Flores, J. Montañez, and J. Vazquez for field assistance; and E. Ezcurra, N. Knowlton, and J. Jackson for comments on the manuscript. This research is part of the "citizen science" project led by the Gulf of California Marine Program at the Scripps Institution of Oceanography. We are grateful to the Walton Family Foundation, the David and Lucile Packard Foundation, and EDF and WWF (Mexico) for their support of the GPS-trackers program. AFJ was supported by NSF grant DEB-1632648 (2016). There are no potential conflicts of interest influencing the objectivity of this report. We are grateful to three anonymous reviewers for their invaluable comments, which greatly improved the manuscript. Supporting Information Filename Description conl12358-sup-0001-SuppMat.docx139 KB Figure S1. Classification of point data generated by a GPS data-logger using the speed to identify where the gear was potentially deployed and retrieve during a gear test for (a) gillnets and (b) trawlers. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. References Avila-Forcada, S., Martínez-Cruz, A.L. & Muñoz-Piña, C. (2012). Conservation of vaquita marina in the Northern Gulf of California. Mar. Policy, 36, 613- 622. Ban, N.C., Mills, M., Tam, J. et al. (2013). A social–ecological approach to conservation planning: embedding social considerations. Front. Ecol. Environ., 11, 194- 202. Barlow, J., Rojas-Bracho, L., Muñoz-Piña C. & Mesnick S. (2010). Conservation of the vaquita (Phocoena sinus) in the Northern Gulf of California, Mexico. In: R.Q. Grafton, et al. (eds.), Handbook of marine fisheries conservation and management, Oxford University Press, New York, pp. 205- 214. Barner, A., Lubchenco, J., Costello, C. et al. (2015). Solutions for recovering and sustaining the bounty of the ocean: combining
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