The significant similarity of Kerguelen and South Georgia icefish Ch.gunnari populations ecology has been revealed. Fish of all lengths and ages are planktonphages. Fish of the first two age groups have been continuously found in the pelagic layer off South Georgia and Kerguelen-Heard. Immature fish also partially distribute in the pelagic layer both in the daytime and at night. Mature fish, as a rule, are at the bottom in the daytime, however in some years they like immature fish, have been caught with pelagic fishing gear in the water column during the daytime.
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:
Data on bottom trawl catch of tagged fish are presented as well as results of tagging of some Antarctic fish in Subarea 88.1. Use of marked trawl hooks as an additional method of fish tagging is proposed for discussion.
Abstract:
On the grounds of data analysis collected by one of the authors – Prutko V.G. in December, 2002-March, 2003 in Subarea 88.1, we determine Antarctic toothfish body length at maturity of 50% females -128-130 cm, males -117-120 cm.
To estimate maturity stages of post-spawning individuals we suggest using double designation, and to control visual estimation of maturity stages number of different oocytes in Antarctic fish ovaries should be measured and calculated, in addition to histological investigations. Dynamics of gonadosomatic index in different periods and for different research areas is presented. Presence of Antarctic toothfish spawning concentrations in the northern part of the research area and presence of “exhausted” individuals are noted. On the basis of the proceeded data and analysis of literature information we came to the conclusion that strict limitation of Antarctic toothfish catch was necessary. Together with the limitation it is suggested paying maximum attention to investigate reproduction ability of the species in question. Brief program of such research is presented.
Abstract:
Detailed materials are presented collected by the author in Subarea 88.1 in December, 2002-March, 2003 on penetration of sub-Antarctic species D.eleginoides, L.immaculatus to polar latitudes (to 72° S). Supposition is expressed that Ross’s rotation conditions mixing of Antarctic and Patagonian toothfish distribution areas and appearance of opah in the polar Ross Sea.
Abstract:
This paper provides an update on seabird research underway in New Zealand. Details of population research including methods and relevant references are provided. Foraging range tracking programme details are also provided, along with details of recorded visits to the CCAMLR area (nil).
Abstract:
Data on maturity, gonadosomatic index (GSI) and length weight of Antarctic toothfish Dissostichus mawsoni were collected from Sub-area 88.1 in the 2002-2003 season by the New Zealand bottom longline vessels Janas, Avro Chieftain and San Aotea II operating in the Exploratory Fishery. The first spawning fish were found in April, a month earlier than in the previous season.
Abstract:
An update on the BioRoss research programme is provided for information purposes. The update includes progress to date, planned research and the future of the programme.