General Conclusions 



The BERPAC expedition of 1988 instituted a series of 

 research projects that greatly amplified the scope of the original 

 program's overall research objectives. The cruise included an 

 8-day stay on Caroline Atoll, an uninhabited necklace of islets 

 enclosing a pristine lagoon. Chapter 1 deals at length with the 

 history, geology, reef structure, botany, and ornithology of this 

 little-studied ecosystem. Notable features of the atoll included 

 a nearly-continuous reef surmounted by 39 islets in various 

 stages of plant succession, many of them covered in virgin 

 forest (Subchapter 1.1); a community of 1 1 species of breeding 

 seabirds. numbering in excess of 1,000,000 individuals 

 (Subchapter 1.2); and a remarkable Acropora -Tridacna reef 

 containing the world's densest known colony of Tridacna 

 clams (Subchapter 1 .4). The inner reef system has developed 

 within a lagoon that is perched several inches above sea level 

 at low tide. New species of plants, lizards, land birds 

 (Subchapter 1.3), and seabirds were discovered for the atoll 

 during the 1988 expedition. 



Caroline also provided an opportunity to compare basic 

 oceanographic parameters between the open ocean, an enclosed 

 lagoon, and the confined waters of the South China Sea. 



In Chapter 2, one of the more recent aspects of marine 

 pollution — plastic contaminants — was examined in the central 

 Pacific Ocean and South China Sea. Surface and subsurface 

 water was sampled and the quantity and distribution of plastic 

 debris determined. Plastics collected from the water were 

 extracted and analyzed for organic pollutants to assess the 

 potential hazard of the transfer of pollutants to marine organisms 

 that ingest plastics. Results of sampling revealed that plastic 

 debris, and specifically raw polyethylene pellets used in 

 manufacturing, is widespread in the Pacific Ocean and South 

 China Sea. Plastics occurred more frequently than did tar balls. 



even in the South China Sea. Organic contaminants were not 

 associated with plastics at any detectable levels. However, 

 subsequent studies demonstrated that plastics can adsorb certain 

 contaminants and that this could represent a potential hazard to 

 marine life. 



In Chapter 3, primary productivity was compared between 

 waters close to and distant from Caroline Atoll. Waters close 

 to Caroline showed less productivity than waters nearer to 

 the equator (Subchapters 3.1 and 3.2). Not surprisingly, 

 mesozooplankton (Subchapter 3.3) and neuston 

 (Subchapter 3.4) diversity and biotnass also increased toward 

 the equator, relative to the waters near Caroline, due in part 

 to the hydrodynamics of the water columns near the equator. 

 The equatorial parts of the Pacific were also much richer in 

 seabird diversity and density than waters at higher latitudes 

 (Subchapter 3.5). One surprise of the expedition was 

 the discovery of a major land bird migration corridor over 

 the South China Sea from Vietnam to Borneo 

 (Subchapter 3.6). 



The second leg of the 1988 BERPAC expedition was the 

 first of a planned series of similar cruises in the tropical Pacific 

 and, as such, should be viewed as a forerunner of expeditions 

 to come. Many disciplines relevant to the unique biology of the 

 central Pacific were not represented in 1988, particularly those 

 concerned with the functioning of coral reef ecosystems. Steps 

 have been taken to issue a broader call to marine biologists to 

 participate in future expeditions in order to further our 

 understanding of the World Ocean and the marine-derived 

 shallow waters and terrestrial ecosystems of which it is 

 composed. If the publication of this volume inspires other 

 biologists to follow, it has fulfilled part of its goal in presenting 

 the varied findings of a successful initial expedition. 



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