corresponds to an arid, hot, and dry cli- Conservation lssues mate. The vcgetation af VIBIRE consists of ten distinctive areas based on flonstic composition and physiognomic character- istics (León de la Luz et al. 1991). Most of Sustainable Development in a Mexícan the flotistic associations found at the Viz- caíno Biosphere Reserve are some type of Biosphere Reserve: Salt Production in Vizcaíno, xerophy tic scrub and haloph yte vegeta- tion. and almost 10% of tlie 447 plant Baja California () species found in the area are endemic (León de la Luz et al. 199 1 ).

Alfredo Ortega-Rubio Vizcaino Biosphere Reserve also has con- Aradit Castellanos-Vera siderable historic and prehistoric impor- Danile Lluch-Cota tance on an international scale. Included in its protected zones are the cave paint- Centro de Investigaciones Biológicas del Noroeste ings and petroglyphs of Las Sierras de Apartado Postal No. 128 Santa Martha and San Francisco (Crosby La Paz, 23070 B.C.S México arid O'Rear 1980. Crosby 1984, Castell- aortega9cibnor.m~ anos and Breceda 1995). These remnants of the historic and prehistoric settlements are considered "human heritage places" ABSTRACT: We analyzed biological inforrnation from an area irr which salt production by UNESCO (UNESCO 1994, Castellanos activities are occurring-Ojo de Liebre (also known as Scmmon's ), a coastal and Breceda 1995). lagoon located witlun Mexico's largest protected area, the Vizcaíno Biosphere Reserve. Populatioii treiids of the primary animal species inhabiting and visiting the area on a VIBIRE protects not only the rnain areaof yearly basis. such as gray whale (Eschrichtius robustus) and inany species of marine arctieological remiiants in the State of Baja birds, from before and after the onset of salt production activities. clearly indicated that California Sur, but also eight endangered salt production is compatible with both biodiversity coiiservation and the sustainable use species, such as peninsular pronghorn (An- of natural resources. Although similar compatibility has been observed for niost salt tilocaprn americana peninsulans). pere- works around the world. this case study is particularly relevant because it is an example grine falcon (Falco peregrinus), anJ desert of how productive activities and nature conservation are compatible. Sustainable devel- fox ( Vulpes nzacmtis) (Breceda et al. 1995). opment is not achieved by suppressiiig the growth of human population, but by searching VIBIRE is one of the most representative for production activities that are efficient in terms of environniental protection and areas of arid vegetation in Mexico (Rze- income revenue for local people. In Mexico. salt production activities at Vizcaíno dowski 1978), and contains 308 terrestrial Biosphere Reserve exemplify how nature conservation and human activity can coexist in vertebrate species (Ortega and Amaga a Latin American protected natural area. 1991). Presence of these species was the primary reason for the Center of Biologi- Index ternrr: , Ojo de Liebre lagoon, salt production, sustainabte cal Research (Centro de Iiivestigaciones development, Vizcdno Biosphere Reserve Biológicas del Noroeste) to promote and Noturof Areos Joumaf 18:63-72 obtain the area's declaration as a biosphere reserve (Ortega and Amiaga 1991 a).

VIBIRE was created by presidential de- cree in 1988 (Ortega et al. 1988. Ortega- MTRODUCTION the remaining 2,183,352 ha considered Rubio and Castellanos-Ven 1994). as part buffer zone (Ortega and haga 199 1b, of UNESCO's Man and the Biosphere The Vizcaíno Biospliere Reserve (VIBI- Tejas et al. 1991). (MAB) Program (Ortega et al. 1989. Cas- RE) is the largest protected area in Mexico tellanos and Ortega .Rubio 1995b). Tlie and one of the largest biosptiere reserves VIBIRE encompasses six climatic subtypes required previous studies (Ortega et al. in the world. It is located in the northem because it spans an area from the Pacific extreme of the State of Baja California Sur Coast to the central mountains and the (Ortega and Arriaga 1991a. Breceda et al. mountains located along the coast of the Papers in the Consewation lssues section 1995; Figure 1). VIBIRE comprises a total Sea of Cortez (Salinas-Zavala et al. 1991). are reviewed by members of the Editorial of 2,546,790 Iia under protection, with The six climate subtypes are part of the Board but are riot rcfereed as are orher 363,438 ha considered the core area and general type BW (Garcia 1964). which articles in the Natural Areas Journal.

Volume 18 (l), 1998 Natural Areas Journal 63 1988). as well as the two current manage- ment plans (Ortega et al. 1990, 1992), al1 recognize the need to address both eco- nomic development and nature conserva- tion for this bea. This extremely arid area of Baja California Sur is the habitat of a relatively diverse and highly endemic bio- ta, which includes some endangered spe- cies, but it has provided its inhabitants with very few altematives for econornic development. There is a great need for productive projects that can provide the jobs demanded by a growing population. especially because local activities such as agriculture, fisheries, and livestock raising are not likely to grow quickly enough to satisfy this demand.

Sustainable development is, therefore. a major goal in the operauon of this Latin American reserve (Castellanos and Orte- ga-Rubio 1995b, Ortega and Castellanos 1995). The management plans as well as the presidential decree address this goal by allowing the rational use of natural resources in the buffer zones. To date, important human settlements are estab- lished both inside and near VIBIRE: San Ignacio, Santa Rosalia, , and Vizcaíno (Castellanos and Mendoza 199 1, Tejas et al. 199 1 ; Figure 1). Produc- tive projects have been developed and sorne are currently operating in VIBIRE (Cas- tellanos and Mendoza 199 1).

Among these developrnents, the inost irn- portant is thc Compania Exportadora de Sal (ESSA). a joint venture of the Mexican federal government and foreign private investments. For several decades, ESSA has continuously operated what still is the largest salt works in the world, producing approxirnately 7,000,000 tons of salt a year. The Guerrero Negro Salt Works is located I within theVIBIRE buffer zone (Figure 1). Figure 1. Locatlun of (he Vizcalnu Blosphere Reserve, (he Ojo de Liebre lagoon, the town of Guerrero Long before the VIBIRE decree, salt pro- Negro, and (he ESSA evaporaiion ponds. Baja California Sur, Mexico. duction activites interacted with the siir- rounding biota in an area where other pro- ductive activities, such as livestock Sorne aspects of the salt works' effect on METfIODS production. are almost entirely absent. Tlus [he ecolog~of are' require From ,992 to ,995, we spent a total of 5 represents an excellent case study for the further resenrch before detinitive conclu- montlis conducting fieldwork at the Ojo evaluation of the degree of compatibility sions can be reached. But our aiialysis of de Liebre lagoon and surrounding area. between salt production and nature con- the available data oii population trends of Our íieldwark was undertaken to confirm servation. soine species of strong conservation inter- data gathered duriiig 830 11 we had,#ady est provides valuable information for de- spent analyzing the literature. both pub- cisioii makers.

64 Natural Areas Journal Volume 18 (l),1998 lished and unpublished, concerning the cause of its impermeable and hypersaliiie every yem from Canada and the United effects of the salt production operation on characteristics) and that lacks potential States (Page and Palacios 1993). tlie regional environment. We gathered productive use (Ortega et al. 1990. 1992). information on the status of natural popu- These ponds are continuously filled with 2 One of the main species inhabiting VIBI- lations of species such as gray whale (Esch- niillion m' of sea water, which is daily RE is the gray whale-the only living richrius robusrus), black brant (Brarira pumped frorn the Ojo de Liebre lagoon mernber of the family Eschrichtidae arid bemicula), peregrine falcon, and marine (Figure 2). Sea water slowly circulates from the most primitive baleen whale. In addi- ,. birds, both before and after the start of salt one pond to the next, becorning more sa- tion to its scientific importance, this spe- production at Ojo de Liebre lagoon. line as natural evaporation occurs. rind cies has aesthetic appeal aiid social and remains for about 2 years before reaching economic significance (Brownell 1977). ,, Most of the published literature on the the smaller hypersaline ponds where salt Once considered under extreme threat of environmental and biological aspects of finally precipitates. extinction (Maravilla 199 1). this whale and the site was written by our colleagues and its recovery received a lot of attentioii from ourselves at our research center (Ortega et Sait production at ESSA consists only of the public, particularly conservation al. 1988, 1989, 1990, 1991. 1992; Ma- the gradual evaporation of marine water. groups. It is considered by some to be an ravilla 1991; Ortega and Maga 1991a, Only marine water, sun, and wind partic- outstanding example of a wildlife man- 1991b; Lluch-Cota et al. 1993; Cancino ipate in this crystallization process. No agement success (Rice and Wolman 1971, and Ortega-Rubio 1994; Castellanos et al. chemicais are added (Figure 2). After pre- Jones et al. 1984, Maravilla 1991). 1994a. 1994b; Castellanos and Breceda cipitation. the salt is mechanically har- 1995; Castellanos and Ortega-Rubio vested, piled. and then transported to a The gray whales occumng at VIBIRE 1995a, 1995b; Ortega-Rubio and Castell- dock located inside the Ojo de Liebre la- belong to the lnrgest of two stocks living anos-Vern 1994; Ortega and Castellanos goon. Each day, two full barges transport in the North Pacific. North Atlantic popu- 1995; Sanabria et al. 1995). the salt to the Cedros Island facilities (Fig- lations are extinct, probably because of ure 1). where salt is loaded on large ves- overexploitation (Mitchell 1974, Brownell sels for final delivery around the world. 1977). Ttie so-called "California" stock KESULTS AND DISCUSSION migrates every year froni summer feeding ESSA was established in 1954 at Guerrero Besides being the largest salt works in the grounds in the Benng, Chukchi, and Beau- Negro, a small town near the Ojo de Lie- world, Ojo de Liebre lagoon is a key world fort Seas to severai coastai areas in north- bre lagoon (also known as Scammon's conservation location. Every winter, gray west Mexico where they reproduce during Lagoon, Figure 1). ESSA facilities consist whales arrive there, both to binh their the winter season. mainly of 34,000 ha of 1-m-deep evapora- calves and to mate (Fleischer 1990, Fleis- tion ponds, built over naturally imperme- cher and Maravilla 1990, Maravilla 199 1). The protection of the whale's winter hab- able, hypersaline soil (Figure 2). The evap- Moreover, large numbers of different spe- itat was one of the primary reasons for oration ponds were built on soil that is cies of migratory birds. such as black brant, declaring VIBIRE a biosphere reserve. Ojo devoid of any native flora and fauna (be- red phalarope, and white pelican. arrive de Liebre lagoon is considered by far the most important area for caiving, followed by San Ignacio and Guerrero Negro (Rice et al. 1981). However, other areas along the coast of Baja California and mainland Mexico are also occupied, though on an irregular basis (Rice et al. 1981, Fleischer and Contreras 1986, Tershy and Breese 1991, Maravilla 1991).

Hunting of gray whale has been going on since prehistoric times by natives of the Benng and Chukchi Seas, and was a tradi- tional activity of the Indian tribes on Van- couver Island and in the present State of Washington. Heavy exploitation began in the mid 1800s and included cornmercial hunting at the reproductive grounds (in- cluding Ojo de Liebre) by American whal- ers during the 1920s (BromI1 1977). Figure 2. Salt productlon process at the Ojo de Liebre lagoon. Marlne water ¡S pumped from the lagoon Estirnates of the stock size before the start to the evaporatlon ponds bullt on hypersallne soil. Marine water spends 2 years slowly circulating of the industrial fishery range between among evaporatlo~iponds until it reaches the crystalliLatlon pond (see text fnr full explanation).

Natural Areas Journal 65 * 10,000 and 25,000 individuals (Hender- a son 1972, Lankester and Beddington 1986). 24 This number decreased significantly,reach- ing its lowest leve1 by 1875-approximate- 22 ly 4,000 animals (Ohsumi 1976). Obsemed e ,- - Modeled 20 Complete protection for the gray whale /'* was implemented in 1948 by the Interna- ul a 18 /" tional Convention for the Regulation of -m Whaling; however, regulated catches by L: 3 2 6 /' the Siberian Aborigines and a small-scale o ;16 4 Alaskan Eskimo fishery are still allowed a3 0 a e E .A (Brownell 1977, Blokhin 1992). Since die + 0' 2 1: early 1970s, [.heMexican government pro- z /- gressively enforced the protection of the 4 -' species and its winter habitat, first by de- 12 -4-'/' claring the calving as whale ref- /' uges (which enables the restriction of boat 10 traffic and fishing during tlie winter; see Rice et al. 198 l), and later by the VIBIRE declaration in 1988 (Ortega et al. 1990). 8 - 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 It is safe to state that the gray whale pop- ulation has been growing at a high rate 1500 during recent decades. During the 1980s. e the population recovered to levels close to e those before the population collapse (Reil- ObSe~ed ly et al. 1983, Rice et al. 1981, Reilly - Linear trend 1984, Cooke 1986). Estimates of the pop- ulation size were some 15,600 individuals 1 o00 UI for 1980 (Reilly et al. 1983), and the Inter- a -m national Whaling Commission estimated c 3 more than 20,000 whales by 1989 (Tershy O and Breese 199 1). Regarding the average La annual rate of increase, Reilly (1987) esti- 0 mated 2.5% for the period 1967 to 1980, S e = 500 and Buckladdet al. (1993) estimated 3.3% from 1968 to 1988 (Figure 3). Concurrent e with this recovery, the population has re- colonized some areas of historic distribu- tion, such as ttie (Ter- &e shy and Breese 1991). e o - 1952 1957 1962 1967 1972 1977 1982 1987 1992 Concerning the potential effects of salt production at the calving lagoons, ESSA Flgure 3. Upper panel: Graj whale population size computed from shore censures (observed) and operations have existed at Ojo de Liebre modeled (aner Buckland et al. 1993). Lower panel: Number of whales at Ojo de Liebre lagoon and linear since 1954. Only two activities take place trend (after Maravilla 1991; value for 1995 &ter O. Maravilla. Centro Regional de Investigaciones Pesqueras, Mexico, pers. corn.). there: marine water is pumped from the lagoon into the evaporation ponds, and two barges daily sail from the dock iiisidc the lagoon to Cedros Island (Figure 1). Regional de Investigaciones Pesqueras, in whales using other calving lagoons and Mexico, pers.com.). One striking feature bays such as San Ignacio, Magdalena. and Figure 3 presents yearly counts of the is a wide year-to-year variation. Sugges- La Paz (Fleischer and Maravilla 1990. number of wliales observed at Ojo de Lie- tions are that envirotimental variability, Maravilla 1991). bre lagoon (from Maravilla 1991; value particularly sea-surfacetemperature, is the for 1995 provided by O. Maravilla, Centro most likely cause, because it would result Despite this variability, it is evident that, in

-- 66 Natural Areas Journal Volume 18 (l), 1998 the long mn, the number of wliales using al., in press). Mer ESSA began its activ- these, some other species, sucti as osprey Ojo de Liebre lagoon increased during the ities in the flatlands surroundiiig the Ojo and peregrine falcon, are breedirig on arti- 1980s and 1990s. It should be noted that de Liebre lagoon, there was an increase in ficial nesting substrates iii the lagoon and the average annual rate of increase (2.7%) both nuinber of niarine bird species and vicinity (Castellanos et al. 1994, Castell- is very similar to the population growth population numbers. anos and Ortega-Rubio 1995). estimates. From this positive trend, no negative impact on the lagoon as a calving There are three main explnnations for sucti Finally, because access to ESSA I'acilities, area can be attributed to ESSA salt pro- an increase. First, one would not expect a salt ponds, and coastal zones leased by ,. duction activities at Ojo de Liebre. This decrease in the nuinber of marine bird ESSA is restricted. no temporary tourist conclusion is consistent with the opinion species in the Ojo de Liebre lagoon be- and fishing camps (which result iti highly of other authors who have suggested that cause tlie operational activities directly modified habitat and nuinerous perturba- t salt production at VIBIRE has not nega- related to the salt production process have tions in the Baja coastal lagoons) have tively affected the gray whale population been confined to only a fraction of the been established in the lagoon littoral (Rice et al. 1981, Maravilla 1991). Swartz lagoon surroundings (Figure 1). and no zones. Vehicular traffic and tourist access and Jones (1983) found no significant dif- significant habitat modifications were made are minimal, controlled, and confined to ferences between the yearly stranded calf in the natural wetlands, deep waters, and particular parts of the lagoon (Figure 1). and calf counts for Ojo de Liebre, Guerre- smali islands (Figure 1). Small islands were ro Negro, and San Ignacio lagoons. Salt the main marine bird breeding habitats in All of tlie data we collected on marine production activities have never been con- 1927, and they still retain this value (see birds shoh clearly that ESSA operations ducted al Laguna de San Ignacio. Massey and Palacios 1994, Castellanos et in the lagoons have not resulted in detri- al., in press). Such values are reflected in mental modification of wintering or breed- Similar conclusions can be derived regard- the presence of high-density colonies of ing habitat, have not had a significant ef- ing the migratory and resident marine birds. alinost the.entire list of species reported by fect on perturbation-sensitive species, and Ojo de Liebre lagoon is one of the most Bancroft (1927) (Castellanos et al., in llave provided new habitats for several important wetlands on the Pacific Fly way ; press), and the colonization of diese is- marine bird species. In the case of osprey it is comparable to the Saii Francisco Bay lands by birds such as peregrine falcon and peregrine falcon (nest-site-regulated wetlands in the United States (Saunders (Castellanos et al. 1994a. Castellanos et al. species), ESSA opperations have provid- and Saunders 1981, Page and Palacios 1997) and laughing gull (Larus atricilla) ed additional nesting substrates (Castell- 1993, Massey and Palacios 1994) and is (Castellanos et al. 1994). Also, habitat anos et al. 1994a, Castellanos and Ortega- the largest concentration area for winter- quality for waterfowl, particularly black Rubio 1995). ing shorebirds (Page and Palacios 1993) brant, a perturbation-sensitive species and waterfowl (Bellrose 1978, Saunders (Kramer et al. 1979), and shore arid other VIBIRE is also the habitat of anotlier spe- and Saunders 1981) iri'the Baja California marine-wintering birds is still adequate, as cies of high conservation interest: penin- peninsula. This wetland complex also is suggested by their large numbers arriving sular pronghom (Antilocapra americana an important breeding spot for seabirds yearly to tlie Ojo de Liebre lagoon wet- peninsularis). The peninsular pronghorn (Castellanos 199 1, Everett and Anderson lands (see Bellrose 1978, Conant et al. is the most eiidangered marnmal species in 1991, Massey and Palacios 1994). 1989, Momson et al. 1992, Page and Pala- Mexico (Cancino and Ortega-Rubio 1994). cios 1993). At the time this article was written, the Whenever species richness and population species' population size was estimated to estimates are available for a sufficient num- Another cause of increased species diver- be fewer than 100 individuals (Cancino et ber of years, increases can be observed sity and population numbers is the conver- al. 1996). Because of its low population both in species and population numbers sion of the estuarine intertidal flats (sensu size and the lack of success in controlling for marine birds (Bellrose 1978; Conant et Cowardin et al. 1989)-an impoverished the causes that reduce its population num- al. 1989; Castellanos and Ortega-Ru- hypersaline habitat surrounding the lagoon bers (habitat loss, hunting, and poaching; bio1995; Castellanos et al., in press). Sev- (Nelson 1921;Figure 1)-to extensive and Cancino et al. 1994),most local specialists eral well-documented examples ilustrate shallow ponds in which the marine biota have recommended capturing from 10 to the positive relationship between the ESSA flourish (Lopez 1991). These ponds pro- 30 individuals of this subspecies and main- operation and the conservation status of vide feeding, resting, and iiesting habitat taining tliem in semicaptivity at La Mesa bird species. for about 88 wintering and resident ma- de la Choya flatland (Canciiio et al. 1994, rine bird species (Exportadora de Sal, S.A., 1996; Cancino and Ortega-Rubio 1994). According to one report (Bancroft 1927), 1996), such as red phalarope (Phalaropus Mesa de la Choya flatland (Figure 1) is aii 17 marine bird species weke breeding in fulicaria), black-necked stilt (Himantopus artificial island, approximately 10,000 ha the Ojo de Liebre lagoon 'wetlands and mexicanus), white pelican (Pelecanus er- in size, formed by the development of islands during the early 1900s. At present. ithmrhynchos), and others (see Momson ESSA facilities; access to the flatland is the number of resident species is 29 (Ex- et al. 1992; Page and Palacios 1993; Ex- controlled by the company. The specialists portadora de Sal S.A. 1996; Castellanos et portadora de Sal S.A. 1996). In addition to believe that the management of this semi-

Natural Areas Journal 67 captive herd is the only way to ensure the erations were fairly self-contained, and al1 factor for any activity witl~inthe Baja pen- survival of this subspecies. supplies, equiprnent, and staff were brouglit insula. Most fresh water comes from un- in from outside. This situation did not derground. so there is both an extra cost We also fecl confident in stating ilist síilt chaiige until 199 1. wlicn tlic Mexican gov- derived froin pumpiiig nnd a sustainability production is compatible with other pro- ernrnent required the cornpanies to hiie problem denved frorn the fact that, iii most ductive activities carried out by Guerrero locally. Even now, the nurnber of local cases, levels of extraction exceed the aver- Negro inhabitaiits. In addition to salt pro- people involved rernains relatively low, and age rate of recharge (Instituto Nacional de duction, ai least three other activities are rnost incorne frorn whale watching goes Estadfstica, Geográfica e Inforrnatica responsible for the population growth with- elsewtiere. During the !994 season, sorne 1996). 9 in VIBIRE: fisheries, agriculture, and tour- $3.3 million was spent by tourists visiting ism. A complete cost-benefit analysis of the lagoon through tours orgaiiized by There were 1,000 citizeris livirig in Guer- these activities throughout the reserve is outside-based cornpanies, but less than rero Negro just after ESSA began opera- i well beyond the scope of the present work; $26,000 (< 1 %) was spent on salaries and tions in 1960, and as of 1990 there were however, a number of comparisons can be purctiases in the area (Young 1995). 10,000 living at Guerrero Negro (Instituto made that provide a long-term perspective Nacional de Estadística, Geográfica e In- on future development in the reserve area, Unlike other activities, whale watching formática 1991). Of these 10,000 citizens, specifically Guerrero Negro. only provides ternporary jobs. Locals in- 4,000 work: 1,200 are employees of ESSA, volved in whale watching are mainly fish- 200 are Tishermen, and 150 are involved in Fishing is an irnportant activity ir1 the coast- ermen who. dunng winter, prefer to use activities that support tourism (e.g., hotel al zones of VIBIRE, pnmarily because of their boats and skills For tourism services and restaurant employees). ESSA ernploy- the high price of the two main resources- because this activity is less risky than fish- ees contribute approximately 70% ($ abalone and lobster. Yearly catches of ab- ing. However, during the rest of the year 1,000,000 U.S.) of the gross inconie of alone and lobster fluctuate between 400 (al1 seasons except for winter) they must Guerrero Negro, fishermen 3%, and tour- and 600 tons. However, in both cases, pro- return to their traditional jobs. Estimates isrn 2%. duction has not increased in any sustained are that the yearly inconie.of these people way during the last decade (Instituto Na- comes half frorn fishing and half from Ari issue of concern is that Guerrero Ne- cional de Estadistica, Geográfica e In- tourism. Moreover, the almost exclusive gro inhabitants are tapping large under- formática 199 1). The main permanent fish- emphasis on whale watchiiig as the only ground reserves of ancient water for their ing settlements are established at least 200 tourist attraction rnakes this activity very survival. According to official data on the km from Guerrero Negro, along the west vulnerable to rnarket changes (Young hydrology of the region (Instituto Nacio- coast of the Vizcaíno region and include 1995). nal de Estadística, Geográfica e Infonnáti- 6,000 persons living in these communities ca 1996). the underground reserves of water (Instituto Nacional de Estadfstica, Geográ- Finally. Young (1995) stressed that it is in the Vizcaíno watershed (wliich includes fica e Informatica 1991). unlikely these problems will be solved in Guerrero Negro) are recharged annually the iiear future. at least as long as the with 40,000,000 m3 of water. Meanwhile, There is no published information on eco- current organization of the activity pre- 42,000,000 m3 of tlus underground water tourism at Ojo de Liebre lagooii. Howev- vails. The operation of wliale watching reserve are exttacted annually withiri the er, Young (1995) conducted a very corn- skiffs is attractive to rnariy fishing families region. Rough estirnates indicate that Guer- plete analysis of this activity at San Igna- and draws oii ttie equipment, skills, and rero Negro citizens (700,000 rn3) and salt cio lagoon. which is very similar, in niost experience íishertnan already have. To seek production activities (300,000 m3) in the of its social-economic aspects, to Ojo de returns from other services, more invest- buffer zone consume approxirnately only Liebre. Whale watching, the only tourist rnent is required in activities where locals 2% of the total extracted (Instituto Nacio- attraction, has not been a traditional op- have little or no experience. Thus, Few nal de Estadfstica, Geográfica e Informáti- portunity for local cornrnunities, in that it locals are interested in diversifying. In the ca 1996). niese official data indicate that has generated only a small number of the long run, tourism at the lagoons depends rnost of the Vizcaíno watershed water ex- - jobs and development that these commu- largely on the unperturbed image of these tracted in the region (86%) is consurned nities deinand. Beginning in the early areas. The ttuesliold beyond which tour- by agricultural activities occurring in the 1970s. whale watching was developed by isrn development can go, without desuoy- zone. Most of these agricultural activities foreign companies (mainly from the Unit- ing the very attraction upon which it is are extremely inefficient in their use of ed States). Initial operations involved com- based, is very low. these huge quantities of underground wa- mercial sport-fishing enterprises from ter (Ortega et al. 1992). Thus, any further southern Califomia that hired out their The prospects of long-tem development increase in cultivated area is unlikely and boats during slow periods of tlie fishing of agricultural activities at VIBIRE are urisustainable. Instead, planners recom- season, arid tourism companies that pro- poor under current conditions. Agriculture mend enforcing both a higher technical rnoted travel by land in the peninsula, in- dernands large voluriies of water. and wa- level of agricultural practices and the pri- cluding visits to the calving lagoons. Op- ter quantity is the inost importaiit limiting oritization of other activities that generate

-- 68 Natural Areas Journal Volume 18 (!), 1998 more economic profit per unit volume of ly at Ojo de Liebre lagoon. patibility is not the result of the relatively consumed water (Instituto Nacional de recent designation protecting the area, but Estadistica, Geográfica e Informática Olficial management plans developed lor rather has been the case for several de- 1996). VIBIRE recognize the importance of salt cades. We believe that the sitiiation nt VI- production activities there (Ortega et al. EIRE provides a valuable model for pro- Two activities that generate greater eco- 1989, 1992).The management plans explain tected areas in the developing countries of nomic profit per unit volume of water con- that salt production activities are beiiig de- Latin Arnerica. Conservation can be facil- sumed are salt production aiid ecotourism. veloped in the buffer zone of VIBIRE (Or- itated in areas where economic develop- In fact, conipared to ecotourism, salt pro- tega et al. 1989, 1992) by the local inhabit- ment is also possible. As already dernon- duction is, for the local inhabitaiits, mucli ants because the benefits ol such activities strated in other developing countries, pure more profitable. Comparing each liter of are significant from an econoinic point of coiiservation proposals easily becorne un- water devoted to each activity, the revenue view as well as an environmental one. The acceptable to a growing population that for the local people is a Iiundred times rnanagement plans also point out that salt demands new econornic opportunities. more efficient from the salt production production activities are developed on sa- activities than from ecotourism. line soils, which offer no other possibilities ACKNOWLEDGMENTS of productive or conservation use. No native Another issue of concern is the potential fauna and flora were known for these saliile This work was supported by the National for toxic discharges of oil, kerosene, and areas. The rnanagernent plans also establish Council of Sciences and Technology of gas into Ojo de Liebre lagoon by ESSA. that the only poteiitial productive use of Mexico (CONACYT), Project No. 1895P- However, during 40 years of operation in these hypersaline soils is salt production, N9507, and the Centro de Investigaciones the zone, there has been no case of any which is the most efficient productive activ- Biológicas del Noroeste, S.C. We would toxic discharge at Ojo de Liebre lagoon by ity in the region, both in terms of the number like to thank two anonymous reviewers for ESSA. Reviewing al1 the scientific Litera- of people employed and in the income gen- their kind and helpful suggestions, which ture and al1 the Mexican environmental erated. greatly improved an early versio~iof tlie reports concerning Ojo de Liebre lagoon, manuscript. We are indebted to Dr. Ellis we were unable to find a single document It is evident that optimal rnanagement at Glazier for editing the English language dealing with any toxic discharge produced VIBIRE must not ernphasize one econom- of the text, Lolita Vázquez for her expert by ESSA into the lagoon. ic activity over another. and that conserva- secretaria1 assistance, and Cerafina tion efforts are essential not only from an Argüelles for her academic support. ecological perspective but also to sustain CONCLUSION the new opportunities based on ecotour- Alfredo Ortega-Rubio. Environmental Im- Vizcaíno Biosphere Reserve is located in isrn. It should be noted that salt production pact Prvgrarn Chieljcat CIBNOR, directed the most arid and isolated state of Mexico. is a natural process, which rnainly involves the studies that developed the hasis to gen- The absence of profitable productive ac- sea water, wind, and sun-abundant natu- erate three Presideritial Decrees establish- tivities, such as advanced agriculture and ral resources of Baja California Sur. As ing biosphere reserves in Mexico: ihe Viz- cattle ranching, is the main socioeconom- currently conducted, salt production does caíno Desen, The , ic characteristic of this reserve (Castell- not involve the use of any added chemi- and La Sierra de Laguna. He also directed anos and Mendoza 199 1). Traditionally, cals. and no toxic substances are produced the multidisciplinary teams that developed this lack of econornic opportunities has during the process. Salt production is corn- the managernent plans for these reserves. encouraged the migration of reserve in- pletely compatible with biodiversity con- He has published 82 original research habitants to the United States and to the servation and the sustainable use of natu- papers and has edited 9 books. large cities of rnainland Mexico (Castell- ral resources, as observed for most of the anos and Mendoza 199 1). salt works around the world. Al1 the scien- Aradit Castellanos-Vera is a researcher in titic literature that we reviewed stated that the Envimnmental Impact Prograrn at CIB- This problern is kept to a minimum at salt production at coastal salt ponds has NOR. His interests are in vertebrate pop- Guerrero Negro by the availablity of three positive effects on biodiversity conserva- ulation ecology, wildlife conservation, and main economic activites: salt production, tion (Britton and Johnson 1987, Calvo- pmtected areas planning qnd rnanagement fisheries, and ecotourism. While the former Sending et al. 1987, Bildstein et al. 199 1. in Mexico. two can be considered traditional job op- Alleng and Whyte-Alleng 1993, Martos portunities, ecotourism is relatively recent and Johnson 1996). Daniel B. Lluch-Cota, Associared lnvesti- aiid is sustained by the fact that Ojo de gator ar CIBNOR, is coauthor of the man- Liebre lagoon yearly receives most of the For al1 these reasons, and aiter examining agement plans for the Vizcaíno and the gray whales migrating from the Bering population trends of the many relevani Revillagigedo Islands Biosphere Reserves. Sea to Mexico-almost 70% of the total animal species, we conclude that salt pro- His scienti'fic interests are in marine re- wintering population (Maravilla 1991). duction -&.nature conservation at VIBI- soume variability, both natural and hu- Ecotourism has been growing continuous- RE are compatible. Moreover, this com- man-induced.

Volume 18 (11,1998 LITERATURE CITED nia. Publication No. 4, Centro de Investiga- Conant, B.. J. Voelzer, and S. Armenta. 1989. ciones Biológicas de Raja California sur. Winter waterfowl survey of Mexico's wesl Alleng, G.P.and C.A. Whyte-Alleng. 1993. La Paz. Mexico. coast and Baja California. U.S. Fisli aiid Survey of least tern nesting sites on the Wildlife Service. Portlaiid, Ore. 10 p. south coast of Jamaica. Colonial Water- Castellanos, A. 1995. Avifauna. Pp. 56-59 in birds 16(2): 190-193. A. Ortega and A. Castellanos. eds., Estrate- Cooke, J.G., 1986. On the net recniitment rate gia para el manejo de la Reserva de la Bio- of gray wliales with reference to inter-spe- Bancroft, G.T. 1927. Notes on the breeding of sfera el Vizcafno. B.C.S., México. Publica- cific comparisons. Repon of the Intema- coastal and insular birds of ceiitral Lower tion No. 10, Centro de Investigaciones tional Whale Cornmision 36:363-366. California. Condor 29: 188- 195. Biológicas del Noroeste. 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Natural Areas Journal 71 Reilly, S.B., D.W. Rice, and A.A. Wolman, Sanabria. B.. A. Ortega-Rubio and C. Arguelles- Tershy, R.B. and D. Breese, 1991. Sightings 1983. Populatiori assessment of the gray Mendez. 1995. Food habits of the coyote in and feeding of gray whales in ttie nortliern whale, Eschrichlius robicslus, from Califor- Baja California Sur. Mtxico. Ohio Joumai Gulf of California. Joumal of Mammalogy nia shore censuses, 1967-80. Fisheries of Science 95(4):289-291. 72:830-83 1. Bulletin 8 1(2):267-281. Saunders. G.B. and D.C. Saunders. 1981. UNESCO. 1994. Propenies included in the Rice. D.W. and A.A. Wolman. 1971. Life his- Waterfowl and their wintering grounds in World Heritage List. Documeritation Cen- tory and ecology of the gray whale (Escli- Mexico, 1937-64. Resource Publication ter. UNESCO. Gland, Switzerland. 45 p. richrius robusrus). American Society of , 138.b.~.Fish and Wildlife Service. Wash- Young, E.H. 1995. Elusive edens: linking local Mammalogy, Spec. Publ. 3: 1-142. ington. D.C needs to nature protection in the coastal c, Rice, D.W., A.A. Wolman, and D. Withrow. Swartz, L.S. and M.L.Jones. 1983. Gray whale lagoons of Baja Califomia Sur. México. 1981. Gray whale (Eschnchrius robusrus) (Eschrichrius robicsrus) calf producdon and Ph. D. diss., University of Texas al Austin. . calf production and mortality in the winter mortality in the winter range. Report of the 314 p. *N range. Report of the International Whale Intemational Whale Commision 33503- Commission 33503-507. 507. Rzedowski, J. 1978. Vegetación de México. Tejas. A.. R. Servin, and S. Gallina. 1991. Editorial Limusa. Mexico. 423 p. delimitación. zonificación y tenencia de la Salinas-Zavala,C., R. Coria, and E. Dlaz. 1991. Tierra Pp. 53-71 Ui A. Ortega and L. Ama- Climatologfa y Meteorologla. Pp. 95- 1 16 ga. eds.. La Reserva de la Biosfera El Viz- in A. Ortega and L. Amaga, eds., La Reser- cdno en la Perúnsula de Baja California. vade La Biosfera El Vizcaíno en la Penfnsu- Publication No. 4, Centro de Investigaciones la de Baja California. Publication No. 4. Biológicas de Baja California Sur. La Paz. Centro de Investigaciones Biol6gicas de Mexico. Baja Califomia Sur, La Paz. Mexico.

Volume 18 (1), 1998 72 Natural Areas Journal