首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Quantifying the relative intensity of fishing on New Zealand seamounts
Authors:Richard L O'Driscoll  Malcolm R Clark
Institution:1. National Institute of Water and Atmospheric Research Limited , Private Bag 14 901, Kilbirnie, Wellington, New Zealand E-mail: r.odriscoll@niwa.co.nz;2. National Institute of Water and Atmospheric Research Limited , Private Bag 14 901, Kilbirnie, Wellington, New Zealand
Abstract:New Zealand seamounts support major fisheries for several deepwater fish species, including orange roughy (Hoplostethus atlanticus) and smooth oreo (Pseudocyttus maculatus). Although a high proportion of features in the depth range 500–1000 m have been fished, very little is known about the ecological impacts of bottom trawling on seamounts. The potential impact is likely to be influenced by the spatial extent and frequency of fishing. A new index is presented to assess the relative intensity of trawling on New Zealand seamounts. The fishing effects index (FEI) incorporates information on the density of fishing on the seamount as a proportion of the seabed area and also on tow direction. Detailed fisheries data from more than 250 000 tows were examined to calculate FEI for New Zealand seamounts. The most intensively fished seamounts were on the south Chatham Rise, an area characterised by a large number of relatively small features which were fished serially for orange roughy in the 1980s and 1990s. Other seamounts with high FEI were on the north Chatham Rise, Challenger Plateau, and off the east coast of the North Island. A range of sensitivity analyses indicated that the general rankings of seamounts were relatively robust to the choice of arbitrary thresholds used to assign tows to seamounts.
Keywords:impacts of trawling  deepwater fisheries  seamounts  fishing effort distribution  orange roughy
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号