94 • Technologies To Maintain Biological Diversity 



cheetahs, rhinoceroses, and elephants (10). But 

 collecting mammal germplasm, without keep- 

 ing the animal in captivity, is more difficult and 

 costly. And many of the wildlife specimens 

 maintained in zoos are the survivors of destruc- 

 tive capturing procedures. 



Efforts increasingly are being made through 

 captive breeding to produce stocks for rein- 

 troduction into the wild. The golden lion tama- 

 rin program in Brazil (11) has been successful 

 for example. Less attention has been focused 

 on reintroducing threatened plant species, but 

 the recent reintroduction of a wild olive tree 

 species on the island of St. Helena suggests that 

 this approach is possible (6). 



Perhaps the most important transfer of ge- 

 netic material occurs between agroecosystems 

 and germplasm storage: Landraces produced 

 in traditional farmers' fields are the result of 

 thousands of years of natural and human selec- 

 tion from thousands of different crop varieties. 

 Many varieties can no longer be maintained 

 by the farmers, who abandon them to plant 

 higher yielding crop varieties. But the genetic 

 diversity of traditional varieties is needed to 

 create improved varieties. Thus, collecting ex- 

 peditions to transfer these varieties into offsite 

 storage are critically important to maintenance 

 of the world's agriculture. Germplasm flows 

 from storage back to agroecosystems, via re- 

 search and breeding programs, as new varieties 

 are introduced into agricultural systems. 



Transfers are not always beneficial, however. 

 Livestock that escape captivity can become feral 

 animals with populations so high that they 

 threaten native wild plants and animals. Feral 

 goats on Pacific islands and feral horses on 

 some rangelands of the United States are well- 

 known examples. Similarly, exotic plants in- 

 troduced as ornamentals or agricultural crops 

 sometimes escape to become weeds that crowd 

 out native species. Efforts to capture specimens 

 for living collections can also be destructive. 

 The challenge is to manage the transfers among 

 sites and programs to enhance the positive con- 

 tributions to diversity maintenance and mini- 

 mize the negatives ones. 



Technological Linkages 



Research and technology transfers between 

 diversity management programs can increase 

 the efficiency, effectiveness, and capacity for 

 maintaining biological diversity. Some technol- 

 ogies developed for domesticated species can 

 be adapted for use with wild species. For ex- 

 ample, technologies for offsite maintenance of 

 wild species— particularly germplasm storage 

 and captive breeding— have benefited substan- 

 tially from the research and experience in agri- 

 culture. Perhaps the most dramatic linkage is 

 embryo transfer technologies developed for 

 livestock that are now being adapted to endan- 

 gered species (ch. 6). Similarly, storage tech- 

 nologies developed for agricultural varieties, 

 such as cryogenics and tissue culture, may be- 

 come valuable tools for maintaining collections 

 of rare or threatened wild plant species. 



Like biological hnkages, technological link- 

 ages work both ways. For example, research 

 on living collections has provided information 

 that can be applied to maintaining populations 

 in the wild (2). Likewise, research on wild pop- 

 ulations supplied information on a number of 

 species' special reproduction requirements, 

 which led to successful results with breeding 

 in captivity. 



Technological linkages among institutions 

 engaged in researching, developing, and apply- 

 ing technologies have been limited. Research- 

 ers and resource managers in this area have 

 historically worked in relative isolation, deal- 

 ing almost exclusively with others in their fields 

 of activity. The few interactions that have 

 occurred have had a positive impact. Thus, the 

 potential for benefits from increased coopera- 

 tive work seems apparent, but institutions are 

 slow to make such changes. 



Institutional Linkages 



Exchanges of organisms and technologies 

 have occurred because they have been consid- 

 ered necessary for success of the different pro- 

 grams. However, most programs focus on rela- 

 tively narrow subsets of diversity. Some groups 



