The beginnings of Pearl Oyster Culture in Baja California Sur, Mexico

by Carlos Cáceres Martínez and Jorge Chávez Villalba
Article appeared in World Aquaculture, June 1997.

Contents introduction culture technology seed collection intermediate culture culture notes and references

Introduction

Although many questions about Christopher Columbus remain unanswered, he was undoubtedly the first European to discover that there were pearls in American waters in 1492.(20) Nevertheless, European knowledge of pearl resources in Mexico dates from the conquest by Hernan Cortés in about 1522. The diary of his lieutenant, Fortuna Ximenes, mentions the discovery of native chiefs living in primitive huts along the sea shore, with quantities of beautiful pearls lying carelessly around. In fact, Cortés secured large quantities of the gems from a tribe near the present site of Hermosillo in the state of Sonora. In 1535 the location of pearl reefs was prominently indicated on Cortés' map of this coast.(14)

Following Cortés' explorations of the Pacific coast of México (1533-1538), a number of expeditions were equipped for securing the pearls either by trading with the natives, or in many cases forcing the natives to fish for the pearl oyster species. This latter contact with the Spanish resulted in very bitter feelings on the part of the Indians. It therefore became risky for small traders to venture among them. Arrival of the Jesuits to western Mexico in 1642 led to more amicable relations with the Indians and the restoration of harmony resulted in more favorable development of the fisheries. This fishery became so profitable for the Spanish and sailors stationed in the Gulf of Cortés that they were frequently requested to devote more attention to the fishery of pearls than to their official duties. To stop this practice, the pearl fishery was later restricted to specially authorized persons.(14)

In 1884 President Manuel González inaugurated the policy of granting exclusive permits to pearl reefs. In that year, five permits were granted for a period of 16 years, giving exclusive rights to all shell fisheries in the respective zones. These five grants were immediately consolidated by French and British companies like the Mangara Exploration Corporation, Ltd., which promptly had very profitable fisheries. Their success was remarkable. Dozens of fishing boats fully equipped with airpumps and scaphanders permitted them to work in deeper water than the divers were able to exploit. From the Spanish conquest until 1874, the Mexican pearl fishery was conducted exclusively by divers without any equipment. After 1880 this method was replaced by the use of diving apparatus.

From then on, the pearl fishery became a well-organized industry. Although it seemed that the pearl fishery could not maintain itself by the production of natural pearls only the commercialization of shells for the clothing and fashion market became the principal economic support of this activity. In about 1830 a French trader named "Combier" made experimental shipments to France for button fabrication. Later the market was found to have developed sufficient interest for regular shipments. It was estimated that from 1580 to 1857, 95.000 tons of pearl oyster shells were removed from the Gulf of California. However, in 1857, to establish regulations for resource conservation and protection of the reefs, the Mexican government divided the Gulf of California into four pearling districts and provided that only one of them could be exploited each year. This permitted the reefs to remain successfully undisturbed for three years. (14) At the same time, efforts to produce pearls from cultured animals were conducted in different regions. The first espherical pearls are believed to have been produced between 1890 and 1893 from Pinctada máxima, by William Saville-Kent in the Thursday Islands, Australia. The first patents for the procedure were filed independently by two Japanese, Dr. Nishikawa and T. Mise, who are believed to have had knowledge of the techniques of Saville-Kent. A joint patent was awarded after a series of court battles. Kokichi Mikimoto had received a patent for the production of half pearls in 1896 and quickly thereafter dominated the round pearl culture industry.(11)

According to information obtained by A.P. Cattet in 1893, people at the Tuamotuo Islands dominated the extensive culture of the pearl oyster Pinctada margaritifera. Juveniles were collected using branches of a bush called "miki-miki." Unfortunately, the document written by Cattet does not tell anything about the other culture stages, but it can be assumed that they produced natural pearls through extensive culture. This information was requested by Gastón Vivès and General B. Topete, who was the municipal president of La Paz, capital of lower California, to study the possibility of introducing pearl oyster culture to this region. Vivès was instrumental in providing the information needed to start a company (Criadora de Concha y Perla de Baja Califomia, S.A.) by using his experience with Pinctada mazatlanica. This included knowledge about appropriate environmental requirements, the comprehension of biological processes, and the knowledge of the Tuamotuo Island techniques for the extensive culture of pearl oysters. The pearls produced were exclusively derived from natural sources; nuclei implantation techniques or other artificial procedures were never used.

The company had two products, the shells and the pearls. The company was founded in 1903 and grew exponentially until July of 1914, when installations and records of the company's production were destroyed during the Mexican revolution.(6) For more than five years Vivés attempted the restitution of his ownership from the new Mexican government, but was unsuccessful.

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Culture technology

Although there are two species of oyster capable of producing pearls in this region, only Pinctada mazatlanica was cultured by Gastón Vivès; Pteria sterna was extracted by fishermen and the pearls found in these animals were bought by Vivès who commercialized them in Europe. The culture was conducted in three different stages; seed collection. intermediate culture in nursery-raceways, and culture of large animals on the sea bottom with metal protection. Culture activities were conducted in the Ensenada de San Gabriel, in the Espíritu Santo Island, Mexico. This station was in permanent communication with the city of La Paz, through sail and steam boats which traveled two or three times per week.(7) Company administration resided in La Paz while on the Island a foreman supervised all the technical operations, overseeing more than 1000 workers in the culture procedures.

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Seed Collection

The technique used for seed collection was similar to that employed in Tahiti by the Polynesians, were filament substrates (branches of bursh called miki-miki) attached to floating structures were used to collect spat. For this step Vivès introduced one of his innovations, "floating shadow wood boxes" called "incubators", wich contained the fillament or other similar substrates. In Baja California the "miki-miki" brushes are not available, so branches of a plant called "chivato" (Calliandra sp.) were substituted for seed collection and achieved good results; however, these branches were dispersed in a shorter period of time than the "miki-miki." The incubators, which consisted of a wood frame of 2 meters long, 2 meters wide and 0.5 meter high, were covered with galvanized wire. The incubators were divided into different compartments, which contained branches of chivato, empty mollusk shells and adult pearl oysters. The collectors were installed near the natural banks, and anchored to the bottom using a drilled stone fastened with a chain to the box. Due to the size of the incubators, they were handled with iron tracks located in eight shipyards.(15)

The collectors remained in the water approximately 7 months, from the beginning of July to January of the next year. The apparatus was then towed out to the San Gabriel dock and placed inside of a palm roofed shed having a length of 85 meters and a width of 10 meters. In this shed, the juvenile pearl oysters were carefully separated one by one from the stretchers, branches and shells. The number of juveniles collected was estimated to be 10-12 thousand per incubator. After the separation, the animals were arranged into metallic net trays consisting of a cement base that had several individual compartments (5-6) made of galvanized net. The structure was covered by a metallic net (15x30x5 cm) to isolate the pearl oyster completely. The juveniles oysters were transported in these frameworks to the nursery-raceways to begin the intermediate phase of culture. In 1914 the company had 613 incubators and 2,213 trays for this operation.(5)

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Intermediate culture

The intermediate culture was a grow-out phase under high protection. Vivés improved this step by constructing a nursery-raceway of stone masonry which was operated with the tides.(7) This improvement in design was the most important contribution to the pearl oyster culture at that time. Vivés used the high primary productivity in the waters of an artificial lagoon to provide food for the organisms in the intensive culture system.

Click on the picture to amplify

The nursery-raceways consisted of 36 channels distributed in a zigzag, pattern in six independent series. The water circulated through these channels by a flood-gate system that operated with the tides. The largest series (D) had 16 channels with two gates from the Ensenada de San Gabriel and one gate to the artificial lagoon. The second series (C) had 10 channels with one gate to the Ensenada and one gate to the lagoon. The third section (B) had 4 channels and two gates to the Ensenada. All these channels wore used for intermediate culture. Each channel of the sections B, C and D was protected by a palm roof (about 800 m) to avoid the negative effects of excessive illumination and high temperature. One guard for each channel eliminated predators using a fish spear.(6,6) The last section (A) was used to maintain the animals prepared for the last stage of culture. It consisted of three independent series of two channels and two gates each that were in permanent communication with the Ensenada. The artificial Iagoon was formed using the physiographic features of the Sdan Gabriel Bay. The lagoon was separated by a rubble-work dam of 365 meters in length. 10 meters of bottom base, 6 meters of superior base and 4 meters in height.

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Culture

After the individuals grew to an adult size, they were taken to the open sea and placed on the bottom on hand-made substrates. Just in front of the San Gabriel location the marine bottoms were prepared to initiate the growth-out phase. The substrates consisted of rectangles of different size (e.g., 10x20 m), made of huge quarry stones taken from dales of the Island. For this operation 1900 meters of railroad and several railway trams and carloads were used. The stones were transported to the sites on canoes of 1 to 2 tons in capacity, the floors of which were reinforced with copper plates. At the sites the stones were placed by scaphander divers in a uniform shape called "cuadros." On these sites the water depth never exceeded 10 meters. (5,6) Each substrate type had its own name and its size was well known. In 1914 all the substrates formed a total of 20 hectares in 21 locations; 12 in the Ensenada of San Gabriel and the remainder located around the Espiritu Santo Island. The most important substrates were located in the Ensenada of San Gabriel.

Animals collected at the end of intermediate culture were called "pinctadinas", and were sown by scaphander divers on the stone beds. Each adult pearl oyster, before it was placed on its permanent habitat, was covered with a metallic armor-plating with sharp points around the margin, and provided with a cork that helped orient the whole animal in a vertical position. The base of the armor had an opening to allow the animals to attach by their byssus threads to the stone beds.(6) The animals prepared in this way, were stored in the last channel section (A) in special boxes made of a Wood structure covered by a wire net, until they were transported and placed in the selected locations. Pearl oysters remained on the stone beds under rigorous security for three years or more until the arrival of pearl harvest time. The harvest procedure was performed by 6 or 8 scaphander divers who traveled via several canoes (the company had 64 boats of different sizes including, motor, steam and sail boats) and collected pearl oysters from the substrates. The recovered animals were carried to a large boat (4-5 ft) where opened under strict surveillance.

The records kept by Vivés offer some insight about the operation. The Company sowed 4,654 million pearl oysters on 21 substrates during the last three years of its operation, 1,682 million in 1911, 1,499 million in 1912 and 1.473 million in 1913. The company also had 4 million juveniles in the nursery-raceways. With 613 available incubators the ability to collect approximately 6 million juveniles per year. Considering a mortality of 30% during this stage approximately 4.2 million animals would he placed in the nursery raceways. With a mortality of 20%, in the nursery stage of culture, approximately 3.36 million animals would be available for sowing on the substrates. Apparently not all of the capacity was realized because a constant quantity of approximately 1-5 million organisms was harvested per season. Besides culture activities, foreign companies operated until 1910, prior to the Mexican revolution. Social stability was achieved eight years after the Mexican revolution and productive processes were encouraged by the new government.(12) Juan Vivès, the son of Gastón Vivès, tried to re-initiate the culture operations, but the local socioeconomic structure had changed. The numerous and inexpensive laborers from whom owners obtained a maximum profit during the pre-revolution day-laborer system (6) were no longer available. As a result, no culture activities were undertaken. However, businessmen remained involved in the pearl oyster fishery, operating several dozen fully-equipped boats.(12) More than twenty years of intensive fishery under a free exploitation system devastated the resource.

In 1939 the government permanently banned the pearl oyster fishery. Since then, several research activities have been devoted to the investigation of "the Mexican pearls," some of them to collect scientific information,(17) and others with the possibility of launching a new business enterprise.(10,19) Research efforts have increased steadily since 1985. Different groups have worked in the Sea of Cortés obtaining information on the reproductive cycle,(1) spat settlement,(1,3,4) growth under different culture structures(2,9,16), growth under artificial conditions,(18) and, recently, artificial nuclei and mabe implantation for pearl production.(8,13,15) Preliminary results have been encouraging, and the establishment of two enterprises for pearl production one in Guaymas, Sonora and the other in La Paz is expected. Good results are expected within the next five years when the pearls and the mabes that have been produced will the appraised in the international market.

All information in this article has come from original documents, using records of the complaints made by Vivés to the Mexican government, a field reconstructive study, and direct interviews with Juan Vivés, the son of Gastón Vivés, before he died.

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Notes and References

1. Araya O., 1988. Mastersavehandling Zoologiska lnstitutionen. Sweden, 30 pp.
2. Bervera L., 1994. Tesis Licenciatura U.A.B.C.S. La Paz, B.C.S., México, 80 pp.
3. Bückie L., et al., 1992. Tropical Ecology 33(2):232-240.
4. Cáceres C., Ruiz C, Ramírez ID, 1992. J.Worid Aquacul.Soc. Vol 93(3):232-240.
5. Cariño M., Cáceres C. 1990. Serie Científica, U.A.B.C.S.(No. Esp. AMAC) Vol. 1: 1 -6
6. Cariño M., 1994. J. Shelifish Res. Vol. 13(1): 325-354
7. Diguet L., 1919. Bull. Soc. Fran, d Acclimat: 183-189.
8. García A., 1992. Tesis Maestría CICIMAR-IPN, La Paz, B.C.S., México, 83 pp.
9. Gavtán 1., Cáceres C, Tobías M, 1993. Journal Wold Aquaculture Society Vol.24(4):541-546.
10. George D., 1969. Potentialities of pearl cultivation in México. Technical Report 5 p.
11. Gervis M., Sims N, 1992. ICLAMR Studies & Reviews No. 21, 49 pp.
12. Martínez A., 1983. Tesis Maestría CICIMAR-IPN, La Paz, B.C.S., México, 77 pp.
13. Monteforte M., 1990. Serie Científica U.A.B.C.S.(No.Esp. AMAC) Vol. 1:13-18
14. Secretaría de Fomento, 1919. informes sobre la Compañía Criadora de Concha y Perla de BajaCalifomia, S.A. Archivo Histórico del Estado de Baja California Sur, México.
15. Rangel C., Chávez J., 1995. Desarrollo Científico y Tecnológico del Cultivo de la Madreperia y la Concha Nácar. SEPESCA- UABCS, 104 pp.
16. Saucedo P., 1995. Tesis Maestría CICIMAR- IPN, La Paz, B.C.S., México, 101 pp,
17. Sevilla N., 1969. Revista Soc. Mex. Hist. Nat.30:223-262
18. Serrano S., Salinas D, 1993. Rey. Iny. Cient. 4(1):81-90.
19. Shirai S., Sano Y. 1981. J. Pacific Soc.(Oct):5-23.
20. Younger J., 1968. The book of pearis. Crown Publishers Inc., New York, 2,4 pp.
21. Most of the photographs in this article are from personal documents of the Vivès family, graciously loaned to Carlos Cáceres

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