Environmental Implications of Aquarium-fish Collection in the Maldives, with Proposals for Regulation

Author:

Edwards Alasdair J.,Shepherd Alec Dawson

Abstract

Export of aquarium-fish from the Maldives began in 1980 and in 1989 almost 54,000 marine fishes, worth approximately US$ 130,000, were exported. The collection of aquarium species is confined to a relatively small area around the capital island, Malé. Estimates of annual exports of 95 species were obtained by examining packing-lists held by Maldivian Customs. In parallel, the population densities of about 70 aquarium-fish species were estimated by visual assessment. Using a number of assumptions, potential (maximum sustainable) yields for 65 of these species — those for which export data were available — were estimated for the area (530 km2) within a 13-km radius (one hour's journey by local boat) of Malé.For 27 species there were some reasons for concern about the levels of exploitation, although only 12 of these species appeared to be ‘at risk’ in 1986 (the year of highest exploitation). If the assumptions made in estimating potential sustainable yields were valid, these 12 aquarium-fish species were being overexploited or exploited at levels close to maximum sustainable yields. Should the trade expand threefold, a further 12 species are considered to be potentially at risk of overexploitation. Two species of butterflyfish, Chaetodon meyeri and C. triangulum, which feed exclusively on coral polyps and generally die in captivity after a short time, were being exported in significant numbers. Both clownfishes (Amphiprion spp.) and their host sea-anemones were being heavily exploited. Because of the symbiotic relationship between these fishes and their anemone homes, this group may be particularly susceptible to overexploitation.Damage to branching corals may result from the collection of specimens of Dascyllus aruanus, which shelter within them. With many thousands of individuals of this species being exported each year, this could represent considerable collateral coral damage. Although levels of exploitation of ‘cleaner wrasses’ (Labroides bicolor and L. dimidiatus) appear well below potentially sustainable ones, it is unclear whether the health of reef fishes might locally be adversely affected in heavily exploited areas.Monitoring and regulation of the aquarium-fish trade is discussed, together with the need for collection of catch statistics by those involved in the trade. The importance of regulation of collection techniques, of standards of facilities, and of satisfactory packaging of fish for export, is stressed. If more accurate estimates of sustainable yields are to be obtained, there needs to be monitoring of populations of key aquarium-fish species in designated collecting areas where exploitation levels are known. Until such estimates become available, the cautious approach adopted in the Maldives to estimate yields and set species-based quotas will, it is hoped, prevent local overexploitation.

Publisher

Cambridge University Press (CUP)

Subject

Health, Toxicology and Mutagenesis,Management, Monitoring, Policy and Law,Nature and Landscape Conservation,Pollution,Water Science and Technology

Reference34 articles.

1. Introduction to tropical fish stock assessment, Part 1: Manual;Sparre;FAO Fisheries Technical Paper,1989

2. Smiths’ Sea Fishes

3. Notes and color illustrations of labrid fishes of the genus Anampses;Randall;UO,1974

4. Some simple methods for the assessment of tropical fish stocks;Pauly;FAO Fisheries Technical Paper,1983

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3