Résultats de la recherche
-
VARIATION IN DEMERSAL FISH SPECIES RICHNESS IN THE OCEANS SURROUNDING NEW ZEALAND: AN ANALYSIS USING BOOSTED REGRESSION TREES
constrained to reflect the known performance of trawl gear. Species richness declined with increasing cod-end ... characteristics using an extensive collection of trawl data from the oceans around New Zealand. Analyses were ... ‘stochastic gradient boosting’). Depth was the single most important environmental predictor of variation in ... their depth. Variables describing trawl length, trawl speed, and cod-end mesh size made a substantial ...
Meeting Document : WS-VME-09/P04 : Auteur(s): Leathwick, J.R., Elith, J., Taylor, P., Francis, M.P., Hastie, T.
-
SPATIAL AND TEMPORAL VARIATION IN ATTRIBUTES OF ADELIE PENGUIN BREEDING POPULATIONS: IMPLICATIONS FOR UNCERTAINTY IN ESTIMATION OF THE ABUNDANCE OF BREEDING PENGUINS FROM ONE-OFF COUNTS
with date-specific correction factors to estimate the population attempting to breed at the beginning ... adults, nests or chicks across several or many breeding sites, and the timing of these counts is often ... outside the control of researchers. Time series counts of Adelie penguin breeding population attributes ... (adults, nest and chicks) within the breeding period show considerable variability across space and time ...
Meeting Document : WG-EMM-PSW-08/07 : Auteur(s): C. Southwell, J. McKinlay, R. Pike, D. Wilson, K. Newbery and L. Emmerson (Australia)
-
KRILL FISHERY BEHAVIOUR IN THE SOUTHWEST ATLANTIC
mean travel distances are longer after the least catch levels, and the travel distances decreases as ... close even after considerable number of hauls. The scales of distance after 50 tows from the original ... to year variability in the probabilities of operating within a local range after a number of tows. In ... the 1999/2000 season the probability that hauls would be made within a 30nm range after 300 hauls was ...
Meeting Document : WG-EMM-08/39 : Auteur(s): S. Kawaguchi (Australia)
-
Towards an initial operational management procedure for the krill fishery in Subareas 48.1, 48.2 and 48.3
Paper Title: Towards an initial operational management procedure for the krill fishery in ... (Euphausia superba) in Subareas 48.1, 48.2 and 48.3 requires a basis for the assessment of resource status ... , and an algorithm for specifying the levels of regulatory mechanisms (e.g., a catch control law) that ... depends on the results of the assessment. The development and selection of a procedure requires a basis ... that the size of the resource has fallen too low. To this end a target CPUE level (CPDEtar) is chosen ... projection period considered, rather than the average biomass at the end of the period as might be the case ... the other end (42?). Rather, the Sub-Committee believed that it would always be necessary for the ... the availability of CPUE data) is assumed to commence after 10 years of annual catches of 0.4 million ...
Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 189–219 : Auteur(s): Butterworth, D.S.
-
Analysis of haul data from the South Georgia krill fishery
Paper Title: Analysis of haul data from the South Georgia krill fishery Abstract / Description ... : Data from individual hauls carried out by vessels operating in the South Georgia krill fishery between ... 1994 and 1996 were examined and a range of descriptive measurements reflecting the fishery operation ... were produced. The measurements emphasise that the krill fishery at South Georgia was geographically ... tightly clustered towards the end of the season. After each haul is complete, the distance to the next ... at South Georgia occurs during the austral winter and spans the end of one CCAMLR reporting year ... fish; fishing end time: the time at which hauling started and the net stopped fishing; * haul end ... period: the time between the start and end of fishing; and time between haul: the time between the ...
Science Journal Paper : CCAMLR Science, Volume 5 (CCAMLR Science, Volume 5) : 9–30 : Auteur(s): Trathan, P.N., I. Everson, E.J. Murphy and G.B. Parkes
-
CALIBRATION ERROR IN THE AMLR PLANKTON TIME SERIES
Abstract: Analysis of the time series of the volume of water filtered during tows using a 1.8 m ... Isaac-Kidd Midwater Trawl (IKMT) from 1992 to 2007 showed a marked decline (~35%) in the volume of water ... of rotor counts from the flow meters showed no significant trends. The discrepancy in volume is ... traced to a simple arithmetic error in the calculation of the mouth area of the net. Since 2000, the net ...
Meeting Document : WG-EMM-08/19 : Auteur(s): C. Reiss (USA)
-
A case of giant squid attack on Antarctic toothfish Dissostichus mawsoni Norman, 1937 (Perciformes, Nototheniidae) caught on bottom-set longline in the Ross Sea
Abstract: In the beginning of February 2005, during the hauling of bottom-set longline in the ... Ross Sea (East Antarctic) from the depth of 1480 m to the surface a very large squid taken a large ... by a longline hook, was hauled up to the board of longliner VOLNA. Squid was very active and did not ... aboard but it was registered with the use of photo- and video cameras. This allowed to determine its ...
Meeting Document : WG-FSA-06/P3 : Auteur(s): Petrov, A.F.
-
A suggested bottom trawling survey on the Ob and Lena Banks
hydrodynamic forces opening the codend. These forces, different for different cod end constructions, have great ... Abstract: The paper presents calculations of water flow velocity through the codend under the ... assumption that the flow is uniform and equal on its entire surface. The calculations were made for different ... ratios of cod end length to its diameter, mesh bar length to mesh bar diameter, and for various mesh ...
Meeting Document : WG-FSA-93/10 : Auteur(s): W. Moderhak (Poland)
-
Analysis of krill trawling positions north of the South Shetland Islands (Antarctic Peninsula area), 1980/81–1999/2000
krill, especially at the beginning of the operation each season. In summer, biological factors that ... Abstract: Inter- and intra-annual variability of commercial krill trawling positions for the 1980 ... /81 to 1999/2000 seasons in the area to the north of South Shetland Islands were analyzed in relation ... to biological and environmental factors. Commercial fishing perations concentrated on the outer shelf ...
Meeting Document : WG-EMM-01/35 : Auteur(s): S. Kawaguchi and K. Segawa
-
A bioenergetics model assessment of the prey consumption of macaroni penguins in Subarea 48.3
towards the end of guard and the end of crèche. Our initial results indicate that levels of krill ... Subarea 48.3 during the period when penguins are constrained by breeding. We show that the greatest levels ... similar such analyses should be undertaken for the other krill-eating penguin species breeding in Area 48 ... . Southwell and C. Waluda Title: A bioenergetics model assessment of the prey consumption of macaroni ...
Meeting Document : WG-EMM-16/37 : Auteur(s): P.N. Trathan, L. Emmerson, C. Southwell and C. Waluda