226 Tableau 5 - Pourcentage cumul<strong>at</strong>tf d'abondance par fitage selon les p§riodes du jour {1980). Heure: 00:00 06:00 10:00 06:00 10:00 12:00 Etage: v 6,4% 5,7% 9,3% IV 8,9% 10,3% 18,1% III 8,0% 14,4% 28,2% I I 7,0% 16,0% 30,3% I 4,7% 11,7% 14,1% Chalut YANKEE 41 2,5 m 15,7% 34,9% 58,5% CONCLUSION Les result<strong>at</strong>s obtenus ne peuvent etre consideres que comme partiels, puisqu'il est bien connu que l'ampleur de la migr<strong>at</strong>ion verticale de Pandalus borealis, varie en fonction du temps de l'ann§e {Carlsson et al ., 1978, Smidt, 1978). Cette particularit§ necessite que des essais de peche soient effectues avec 1 'echantillonneur vertical fitage a difffirentes periodes de l'annfie, si 1 'on veut estimer la vulnerabilite de l'espece dans le temps. REFERENCES Alverson, D.L. and W.T. Pereyra (1969}. Demersal Fish Explor<strong>at</strong>ions in the North Eastern Pacific Ocean - An Evalu<strong>at</strong>ion <strong>of</strong> Explor<strong>at</strong>ory Fishing Methods and Analytical Approaches to-Stock Size and Yield Forecasts. J. Fish. Res. Bd. Canada 26: 1985-2001. Axelsen F., J. Frechette etc. Tremblay {1979}. Donnees sur la Crevette (Pandalus borealis) au 1 arge du Labrador. CAFSAC, Res. ·Doc. No 4: 1-33. Barr, L. and R. McBride (1967). Surface-tobottom Pot Fishing for Pandalid Shrimp. Spec. Sci. Rep. Fish., U.S. Fish Wildl. Serv. No 560: 7 p. Beardsley, A.J. (1973}. Design and Evalu<strong>at</strong>ion <strong>of</strong> a Sampler for Measuring the Near-bottom Vertical Distribution <strong>of</strong> Pink Shrimp, Pandalus jordani. Fish. Bull., 71 (1}: 243-253. Carlsson, D.M., Sv. Aa. Horsted and P. Kannev10rff {1978). Danish & <strong>Trawl</strong> <strong>Surveys</strong> on the Offshore West Greenland Shrimp Grounds in 1977 and Previous Years. ICNAF Sel. Papers. No 4: 67-74. 12:00 14:00 16:00 18:00 20:00 14:00 16:00 18:00 20:00 24:00 9,1% 6,3% 9,1% 10,2% 2,5% 15,8% 12,4% 14,5% 13,5% 3,8% 23 '7% 20,7% 16,0% 17,9% 4,0% 29,7% 25,9% 17,0% 11,8% 3,8% 18,9% 17,2% 11,6% 5,0% 2,9% 60,4% 53,4% 36,6% 25,7% 8,7% Carrothers, P.J.G., T.J. Fowlkes, M.P. Connors and A.G. Walker (1969}. D<strong>at</strong>a on the Performance <strong>of</strong> Canadian East Coast Groundfish Otter <strong>Trawl</strong>s. Fish. Res. Bd. Canada. Tech. Rep. No 125: 1-11. Frechette, J. (1978). Estim<strong>at</strong>ion de l'abondance des stocks de crevettes, Pandalus borealis, dans le nord-ouest du Golfe du Saint-Laurent et dans le chenal d' Anticosti. CAFSAC v/orking Paper, No 23: 1-24. Fr§chette, J. and H. Oupouy (1979). Preliminary Biological D<strong>at</strong>a on the Shrimp Stocks <strong>of</strong> Davis Strait. NAFO SCR DOC., 79/X1/8: 1-15. High, W.L., I.E. Ellis et C.D. Lusz {1969}. A progress Report on the Development <strong>of</strong> a Shrimp <strong>Trawl</strong> to Separ<strong>at</strong>e Shrimp From Fish and <strong>Bottom</strong> Dwelling Animals. Comml Fish. Rev. 31{3): 20-33. Pearcy, W.G. (1970). Vertical migr<strong>at</strong>ion <strong>of</strong> the ocean shrimp, Pandalus jordani: A Feeding and Dispersal Mechanism. Cal. Fish and Game 56: 125-129. Smidt, E. {1978}. Diurnal Vari<strong>at</strong>ion in Shrimp C<strong>at</strong>ches on the Offshore Grounds in ICNAF Divisions 1B and 1C. ICNAF Sel. Papers. No 4: 45-46. Tobey, A. et J. Rycr<strong>of</strong>t {1978}. Mise au point d'un chalut pelagique a crevettes 1977, Golfe du Saint-Laurent. Service des Peches et de la Mer, Rapp. tech. No 101: 1-49.
Sampling Techniques Teclmiques d'echantillolU\age