Antarctic krill ( Euphausia superba ) is harvested using different design midwater trawls. Knowing the selective properties between trawls crucial information for management of resources. This study compared catch patterns commercial at similar times and overlapping fishing grounds based on scientific data collected by observers onboard trawlers Long Teng (LT) Fu Rong Hai (FRH). The results sho...

Japanese Spanish mackerel ( Scomberomorus niphonius ) is an important fish species in the China Seas with wide distribution, extensive migration, and high economic value. This has been yielding fisheries production despite experiencing continuously fishing pressure conversion from gillnet to trawl harvesting. Meanwhile, changes life-history traits have observed, including earlier maturation sma...

Several expeditions in recent years to Isla del Coco have increased the total number of species of fishes known from the island. Several of these species have been described as new endemics (Bussing 1983, 1990, 1991a, 1991b, 1997). During the 1972 R/V Searcher Expedition to Costa Rica several trawl collections were made around Isla del Coco. At five localities in depths between 110 and 180m, 86...

Freshwater flows have an important influence on the balance of fish species in estuaries. As well as supporting general ecosystem health, these flows are also necessary to comply with Australia-wide legislation aimed at the sustainable management of water resources. The Coastal Zone CRC and Fisheries Research and Development Corporation (FRDC) instigated the ‘environmental flows for estuaries’ ...

Several approaches exist for the estimation of technical efficiency. In this paper the four most relevant ones (Data Envelopment Analysis, Stochastic Production Frontiers, Panel Data and Distance Functions) have been compared. The different approaches have been applied to the to the Spanish Trawl fishery that operated in Moroccan waters. The study highlights some of the problems arising from th...

Two trawl surveys in the Northeastern Aegean Sea, conducted in 1997 and 2007 yielded a catch composition which, when re-expressed through the new concept of ‘mean temperature of the catch’ (MTC) yielded an MTC increase of 0.25 0C per decade, which is higher of the global MTC increase rate between 1970 and 2006, but slightly lower than the observed temperature increase in the Northeastern Aegean...

In most decision-making involving natural resources, the achievements of a given policy (e.g., improved ecosystem or biodiversity) are rather difficult to measure in monetary units. To address this problem, the current paper develops an environmental cost-effectiveness analysis (ECEA) to include intangible benefits in intertemporal natural resource problems. This approach can assist managers in...

Dynamical relation between ship's motions and warp tension while towing a trawl net was identified by the use of statistical method to be the multivariate AR model. Using this system identification method, the various towing system parameters were obtained by analysing the records of measuring ship's motions and warp tension during the fishing operations in several sea conditions. Based on thes...