000 02477cam  2200349zi 4500
006m     o  d f      
007cr |n|||||||||
008190924s1979    qucd   #ob   f000 0 eng d
040 |aCaOODSP|beng|erda|cCaOODSP
043 |an-cn---
0861 |aFs70-8/79-29E-PDF
1001 |aPowles, Howard, |eauthor.
24510|aHerring catch per unit effort in the Magdalens trap fishery and implications for gulf herring stock assessment / |cH. Powles, J. Boulva, P. Spenard.
264 1|aQuébec, Québec : |bDirection de la recherche, Ministère des Pêches et Océans, |c[1979]
300 |a1 online resource (11 pages) : |bcharts.
336 |atext|btxt|2rdacontent
337 |acomputer|bc|2rdamedia
338 |aonline resource|bcr|2rdacarrier
4901 |aCAFSAC res. doc. ; |v79/29
500 |a"Not to be cited without permission of authors"
504 |aIncludes bibliographical references (page 4).
520 |a"It has been suggested, based on a consideration of schooling behaviour and on data from North Sea herring fisheries, that catchability in mobile gear fisheries on schooling pelagic fish stocks increases with decreasing stock size, and therefore that fishing mortality is not proportional to fishing effort in such fisheries (Pope, 1978 MS, most recently). Under this hypothesis, CPUE in mobile gear fisheries would vary little with stock size above a critical lower limit of stock size (Fig. 1). Although not stated by Pope (1978, MS), it appears intuitively reasonable that below a critical stock size both catchability and catch per unit effort would fall off rapidly (Fig. 1). In inshore fixed gear fisheries, on the other hand, CPUE should change in proportion to stock size (Pope, MS, 1978) (Fig. 1). If Pope's hypothesis is correct, FT (terminal fishing mortality) values for cohort analyses calculated from mobile gear effort and fishing mortality may be too low and biomass estimates from the analyses too high"--Introduction.
653 0|aHerring
7001 |aBoulva, J.‏‎ |q(Jean)|eauthor.
7001 |aSpénard, P‏., |eauthor.
7101 |aCanada. |bDepartment of Fisheries and Oceans.
830#0|aCAFSAC research document (Canadian Atlantic Fisheries Scientific Advisory Committee)|v79/29|w(CaOODSP)9.869616
85640|qPDF|s619 KB|uhttps://publications.gc.ca/collections/collection_2019/mpo-dfo/Fs70-8-79-29-eng.pdf