Ch. 4— Interventions To Maintain Biological Diversity * 91 



per species. Managers of offsite collections face 

 the dilemma of maintaining populations large 

 enough to ensure viability and at the same time 

 providing refuge to as many species as possible. 



Historically, the primary objectives of living 

 collections have been research and display. 

 However, growing concern over the loss of bio- 

 logical diversity is leading to greater efforts to 

 develop collections for their conservation po- 

 tential. Offsite facilities are also used to breed 

 and propagate organisms, so they no longer rely 

 solely on collecting from the wild to replenish 

 their stocks. Instead, they can make a positive, 

 direct contribution to species' survival. 



Offsite Maintenance in 

 Germplasm Storage 



Storage of dormant seeds, embryos, and clonal 

 materials, or germplasm storage, is the most 



cost-effective method to preserve the genetic 

 diversity of the thousands of agricultural vari- 

 eties and their wild relatives when biological 

 factors allow (5). As farmers increasingly aban- 

 don the traditional varieties in favor of geneti- 

 cally uniform, modern ones, the preservation 

 of diverse, locally adapted crops will depend 

 heavily on offsite storage (1). 



The need to maintain a convenient source 

 of germplasm for breeding purposes and the 

 ability to draw on germplasm from different 

 geographic areas are important objectives met 

 by the offsite storage systems (see ch. 7). Germ- 

 plasm storage is also the principal method for 

 maintaining identified strains of microbes (see 

 ch. 8). And it is increasingly used to store wild 

 plant species and a few wild animal species. 



DECIDING WHICH MANAGEMENT SYSTEM TO APPLY 



The efficacy of onsite and offsite technologies 

 depends on biological, political, and economic 

 factors. The following four chapters in this re- 

 port examine how these various considerations 

 determine which technologies are applied. Gen- 

 eral observations on how these factors help 

 match management systems to conservation ob- 

 jectives are considered here. (See table 4-2 for 

 a summary of objectives.) 



Biological considerations are central to the 

 objectives and choice of systems. Because not 

 all diversity is threatened, the task of maintain- 

 ing it can focus on the elements that need spe- 

 cial attention. Biological uniqueness is impor- 

 tant in setting priorities for conservation 

 programs. A unique species — one that is the 

 only representative of an entire genus or fam- 

 ily, for example, or a species with high esthetic 

 appeal— may be the focus of intensive conser- 

 vation management either onsite, offsite, or 

 both. 



Biological uniqueness can present problems 

 in applying conservation technologies, because 

 species-specific research is often required to 



develop management or recovery plans (ch. 5). 

 Species with unique reproductive physiology, 

 for example, often cannot be maintained off- 

 site until a considerable investment has been 

 made in developing propagation techniques (ch. 

 6). 



Political factors also influence conservation 

 objectives and management systems. Commit- 

 ments of government resources, policies, and 

 programs determine the focus of attention and, 

 to a large extent, such commitments reflect pub- 

 lic interests and support. For example, in the 

 United States a disproportionate share of re- 

 sources is devoted to conservation programs 

 for a select few of the many endangered spe- 

 cies. Substantial sums have been spent in 11th- 

 hour efforts to save the California condor and 

 the black-footed ferret, while other endangered 

 organisms such as invertebrate species receive 

 little notice. 



National instability may also threaten biologi- 

 cal resources either directly in the cases of civil 

 strife or warfare or indirectly through encourag- 

 ing neglect. Such cases warrant special efforts 



