Discrimination of Macrourus whitsoni and M. caml (Gadiformes, Macrouridae) using otolith morphometrics
There is no abstract available for this document.
Comparison of two methods to assess fish losses due to depredation by killer whales and sperm whales on demersal longlines
There is no abstract available for this document.
Abstract:
The current season (2014/15) is the final one of the first three-season research which began in 2013 in data-poor fisheries. In the present report, the next three-season (2016-18) research plan in Subarea 48.6 was revised using the updated CCAMLR C2 and Observer data.
The stock sizes for five research blocks (48.6_1, 48.6_2, 48.6_3, 48.6_4 and 48.6_5) were estimated by the Petersen estimator and the CPUE x seabed analogy method. The stock size estimate using the Petersen estimator was relatively consistent with that using the CPUE method (using Division 88.2H as a reference area) for Dissostichus mawsoni in block 48.6_2. However, the estimates using the Petersen estimator were two-three times larger than those using the CPUE method in the block 48.6_3 and 48.6_4. Predicted numbers of tag recaptures from the estimated stock sizes using the both Petersen and CPUE methods (using Division 88.2H as a reference area) were relatively consistent with the observed numbers for D. mawsoni in the block 48.6_2 for 2012/13 and 2013/14 seasons. The predicted and observed numbers using either method were generally inconsistent for Dissostichus spp. in other blocks.
In the current season three Dissostichus mawsoni tagged and released in the previous seasons in the ice shelf block 48.6_4 were recaptured in the same block, which made it possible to estimate the stock size using the Petersen method for the block for the first time.
Understanding of the resource structure through clarification of their life history is essential to establish stock assessment and robust stock/ fisheries management of Dissostichus spp. population(s) in data- poor exploratory fisheries. During the second three-season research, we will continue enhanced tagging program, and collection and analysis of biological data including otoliths and gonads to clarify migration route and associated life stages of the fish.
To this end, we propose to follow the current research style in the current research blocks for the second three-season research with the sample sizes re-estimated following the procedure recommended at the WG-FSA in 2013 in order to maximize the expectation of tag-recapture to the extent possible under the precautionary exploitation rate. We expect further progress of tagging research in the southern research blocks during the next three-season research because several fish tagged and released in the preceding seasons began to be recaptured.
In addition we propose the westward extension of the research block 48.6_4. The expanding the boundaries of the research block may promote sufficient utilization of the catch limit, which enables us to make more reliable stock estimation, and also be more likely to detect tagged fish that had moved off research block to the continual slope/shelf.
There is no abstract available for this document.
There is no abstract available for this document.
There is no abstract available for this document.
There is no abstract available for this document.
Abstract:
CCAMLR has been managing the krill fishery without sufficient measures needed to meet the requirements of Article II of the Convention. To meet these requirements ASOC seeks key improvements in the management of Antarctic krill fisheries, including establishing feedback management procedures, requiring 100% scientific observer coverage on board krill vessels, and implementing further protective measures to prevent excessive concentration of krill fishing in coastal areas close to predator colonies in Subarea 48.1. This is of particular relevance since fishing has in recent years been concentrated in coastal locations in 48.1.
Abstract:
En 2014, la Comisión reconoció la magnitud de la evolución registrada en los últimos años con relación a la pesca de investigación en pesquerías exploratorias, pesquerías cerradas y otras áreas, y solicitó un análisis de los requisitos de la MC 21-02 y otras medidas relacionadas (p. ej., las MC 21-01 y 24-01) a la luz de dicha evolución. Resulta evidente que hay una cierta desconexión entre la clasificación ‘de trabajo’ de las pesquerías y el marco regulatorio, y sería recomendable que el Comité Científico y la Comisión reconsideraran la actual clasificación y nomenclatura de las pesquerías exploratorias y cerradas para reajustarlas de acuerdo al marco regulatorio. Sería también recomendable examinar las medidas de conservación pertinentes a fin de determinar los requisitos de datos, y el proceso de obtención de esos datos, respecto de todas las pesquerías de austromerluza que no sean pesquerías establecidas. Una opción sería considerar desglosar el formulario del Plan de investigación de la MC 24-01 (Anexo A, Formato 2) y convertirlo en un anexo de la MC 41‑01, teniendo presente que para ello se necesitaría cambiar la clasificación de algunas pesquerías de “cerradas” a “exploratorias”, y también contar con medidas de conservación nuevas o modificadas que incluyan un límite específico para la captura de investigación.
