Effect of allocation and stratification strategies on precision of survey abundance estimates for Atlantic cod (Gadus morhua) on the eastern Scotian Shelf
One of the primary uses of bottom-trawl survey data, with respect to fisheries management, is the estimation of abundance of the species involved. Stratified-random surveys have been conducted on the eastern Scotian Shelf since 1970. The precision of abundance estimates for Atlantic cod (ages 5-12)...
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ftciteseerx:oai:CiteSeerX.psu:10.1.1.615.21 2023-05-15T15:27:06+02:00 Effect of allocation and stratification strategies on precision of survey abundance estimates for Atlantic cod (Gadus morhua) on the eastern Scotian Shelf S. Gavaris S. J. Smith The Pennsylvania State University CiteSeerX Archives 1987 application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.615.21 http://journal.nafo.int/j07/gavaris.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.615.21 http://journal.nafo.int/j07/gavaris.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://journal.nafo.int/j07/gavaris.pdf text 1987 ftciteseerx 2016-01-08T14:42:37Z One of the primary uses of bottom-trawl survey data, with respect to fisheries management, is the estimation of abundance of the species involved. Stratified-random surveys have been conducted on the eastern Scotian Shelf since 1970. The precision of abundance estimates for Atlantic cod (ages 5-12) from these surveys was found to be inferior to what would have been obtained if simple random surveys had been conducted. These results were primarily due to suboptimal allocation of stations to strata. Historical data were used to devise alternative sampling strategies. This analysis indicated that the number of strata could be reduced considerably without loss of precision. An additional and important benefit of the smaller number of strata would be increased flexibility for allocation. With the present level of sampling, it would be necessary to reduce the number of strata to achieve proportional allocation of stations or to approximate optimal allocation. Text atlantic cod Gadus morhua Unknown |
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ftciteseerx |
language |
English |
description |
One of the primary uses of bottom-trawl survey data, with respect to fisheries management, is the estimation of abundance of the species involved. Stratified-random surveys have been conducted on the eastern Scotian Shelf since 1970. The precision of abundance estimates for Atlantic cod (ages 5-12) from these surveys was found to be inferior to what would have been obtained if simple random surveys had been conducted. These results were primarily due to suboptimal allocation of stations to strata. Historical data were used to devise alternative sampling strategies. This analysis indicated that the number of strata could be reduced considerably without loss of precision. An additional and important benefit of the smaller number of strata would be increased flexibility for allocation. With the present level of sampling, it would be necessary to reduce the number of strata to achieve proportional allocation of stations or to approximate optimal allocation. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
S. Gavaris S. J. Smith |
spellingShingle |
S. Gavaris S. J. Smith Effect of allocation and stratification strategies on precision of survey abundance estimates for Atlantic cod (Gadus morhua) on the eastern Scotian Shelf |
author_facet |
S. Gavaris S. J. Smith |
author_sort |
S. Gavaris |
title |
Effect of allocation and stratification strategies on precision of survey abundance estimates for Atlantic cod (Gadus morhua) on the eastern Scotian Shelf |
title_short |
Effect of allocation and stratification strategies on precision of survey abundance estimates for Atlantic cod (Gadus morhua) on the eastern Scotian Shelf |
title_full |
Effect of allocation and stratification strategies on precision of survey abundance estimates for Atlantic cod (Gadus morhua) on the eastern Scotian Shelf |
title_fullStr |
Effect of allocation and stratification strategies on precision of survey abundance estimates for Atlantic cod (Gadus morhua) on the eastern Scotian Shelf |
title_full_unstemmed |
Effect of allocation and stratification strategies on precision of survey abundance estimates for Atlantic cod (Gadus morhua) on the eastern Scotian Shelf |
title_sort |
effect of allocation and stratification strategies on precision of survey abundance estimates for atlantic cod (gadus morhua) on the eastern scotian shelf |
publishDate |
1987 |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.615.21 http://journal.nafo.int/j07/gavaris.pdf |
genre |
atlantic cod Gadus morhua |
genre_facet |
atlantic cod Gadus morhua |
op_source |
http://journal.nafo.int/j07/gavaris.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.615.21 http://journal.nafo.int/j07/gavaris.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
_version_ |
1766357558463823872 |