128 • Technologies To Maintain Biological Diversity 



IITIES 



Onsite management of natural areas has usu- 

 ally been focused on limiting the impacts of out- 

 side pressures. In multiple-use protected areas, 

 the technologies used to maintain biological 

 diversity are mainly based on manipulation of 

 habitats or populations to favor particular spe- 

 cies. These methods, many of which derive 

 from the fields of natural history and wildlife 

 management, are effective for the target spe- 

 cies. Biologists generally agree, however, that 

 broad biological diversity values are not ade- 

 quately served by species management alone. 

 This approach necessarily concentrates on spe- 

 cies with immediate commercial or recreational 

 value and lets too many others, with less obvi- 

 ous values, perish if they do not happen to live 

 in the type of environment maintained for the 

 target species. Thus, technologies are needed 

 to maintain diversity at the ecosystem level. 



Onsite maintenance technologies commonly 

 have been developed in relatively well-known 

 temperate zone ecosystems. Plant and animal 

 communities in these ecosystems generally can 

 recover from moderate human disturbances if 

 they are protected for years or decades. But bi- 

 ologists are not sanguine about adapting these 

 technologies to tropical and other ecosystems, 

 such as coral reefs, that are poorly known and 

 that have much less natural ability to recover 

 from disturbances. 



Although most existing onsite technologies 

 are focused on natural areas where develop- 

 ment is restricted, attention is beginning to be 

 directed beyond simple protected area pro- 

 grams. Resource development planning meth- 

 ods that treat conservation as an integral part 

 of economic and social development have been 

 devised and tested. These strategies hold prom- 

 ise, but they need to be taken from the concep- 

 tual stage to practical implementation. 



The remainder of this chapter addresses these 

 and other opportunities to improve the re- 

 search, development, and application of onsite 

 technologies to maintain biological diversity. 



An Ecosystem Approach 



An ecosystem approach is necessary to main- 

 tain biological diversity onsite for many rea- 

 sons: 1) because the numbers of threatened spe- 

 cies and genetically distinct populations is so 

 high, 2) because so little is known about life his- 

 tories or even the identity of many species, and 

 3) because many species are interdependent. 

 Yet attempts to develop and implement ecosys- 

 tem approaches are few. 



In the United States, development of onsite 

 maintenance technologies is largely the task of 

 Federal land-managing agencies, such as the 

 National Park Service, the Forest Service, the 

 Fish and Wildlife Service, and the Bureau of 

 Land Management. The mandates of these 

 agencies emphasize species- and habitat-ori- 

 ented technologies. A shift toward more eco- 

 system-oriented management would require 

 policy changes within the agencies. Most, for 

 example, consider an inventory of an area's bio- 

 logical diversity and the investigation of spe- 

 cies interactions to be appropriate activities for 

 basic research programs but not appropriate 

 as pragmatic resource management activities. 

 Changes in policies to encourage an ecosystem 

 approach to protected areas may not occur 

 without a congressional mandate directing 

 agencies to manage lands and bodies of water 

 in a way that maintains ecosystem diversity. 



An important strategy for maintaining diver- 

 sity is to safeguard representative samples of 

 ecosystems from changes that would reduce 

 their diversity. The United States lacks a com- 

 prehensive program for ecosystem diversity 

 maintenance, although some efforts are being 

 made through existing programs. The U.S.- 

 MAB program is attempting to establish sam- 

 ples of ecosystems in the United States. Because 

 the areas are identified on the basis of ecologi- 

 cal criteria rather than political boundaries, 

 various Federal, State, and private organiza- 

 tions must cooperate to implement the program 

 successfully, which may explain the sluggish 



