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1. Areal and seasonal extent of sea-ice cover off the northwestern side of the Antarctic Peninsula: 1979 to 1996

   6 km 2 /month. This index may be used in conjunction with studies of variability in biological ... measuring 1.25 x 10 6 km 2 off the northwestern side of the Antarctic Peninsula indicates that there were ... with features described by Stammerjohn and Smith (1996) for ice cover in the Bellingshausen Sea ... years. It is anticipated that the annual index may be easily updated with new data, facilitate ... index of sea-ice cover in units of 10h km2/month. This index may be used in conjunction with studies ... covered with sea-ice for at least one month. Although there does not appear to be a trend in the total ... , Figure 4). It is suggested that these values be used as a single index of ice cover for the area off ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 65–73 : Autor(es): Hewitt, R

2. Modelling variability and estimating power to detect change in Adélie penguin fledgling weights

   finding is that it may be possible to simplify future monitoring, such that fledgling weight is measured ... variability of fledgling weights. These models assume that data are collected during a fixed CEMP five-day ... period corresponding to the average peak fledging period. Modelling assumes that fledgling weights are ... year, but there was no evidence that the rate of decline differed between years. A consequence of this ... the rate of decline differed between years. A consequence of this finding is that it may be possible ... was assumed that the Si, si and eij terms are independent and are normally distributed with mean 0 ... , the distribution of the statistic t is well approximated by a t-distribu- tion with d = (r – 1) + (c ... power of the test can be determined using a non-central t-distribution, as Pr(t(d,λ) > tα(d)) where t ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 191–200 : Autor(es): Emmerson, L.M., C. Southwell and J. Clarke

3. Size at sexual maturity of Patagonian toothfish (Dissostichus eleginoides)

   that L m50 occurs at 78.5 cm total length for male and 98.2 cm for female fish. In 1997 the results for ... male fish were essentially the same. For female fish there is evidence that in 1997 a significant ... allowing for this bias indicates that L m50 for female fish in 1997 was no different to that for 1996. The ... was that, due to the closure of the fishery, there were no data for August 1996; this category ... condition at that time was 96%, the effect would be negligible at the population level. Analysis of the ... PROBITANALYSIS procedure, but it can be seen from Table 3 that the confidence limits for the estimated values ... is declining in successive months. We offer no explanation for this but note that it may be a ...

   Science Journal Paper : CCAMLR Science, Volume 6 (CCAMLR Science, Volume 6) : 37–46 : Autor(es): Everson, I. and A.W. Murray

4. Precautionary measures for a new fishery on Martialia hyadesi (Cephalopoda, Ommastrephidae) in the Scotia Sea: an ecological approach

   vary. In common with other ommastrephids, the species is probably semelparous. It is proposed that the ... consumption data because comprehensive sampling can be carried out during their breeding seasons. A ... 000 tonnes, with an upper estimate of 550 000 tonnes if less reliable data are included. M. hyadesi ... spawns between autumn and mid-summer with peak hatching in winter/spring. Its life span has not been ... Convention Area suggest that M. hyadesi may live for two years, but this may vary. In coinmon with other ... fishing season to avoid direct competition with what is perceived to be the most sensitive predator ... 96 9 6 9 6 It is a safe assumption that M. hyadesi, in common with all the better-known ... indication of its production level. The problem is to estimate the proportion of this that could be ...

   Science Journal Paper : CCAMLR Science, Volume 4 (CCAMLR Science, Volume 4) : 125–139 : Autor(es): Rodhouse, P.G

5. A proposed management procedure for the toothfish (Dissostichus eleginoides) resource in the Prince Edward Islands vicinity

   , whereas catch-at-length information indicates that past catches have had relatively little impact on ... catches made. An MP with control parameter values specified is proposed for implementation based on the ... -recruitment curve steepness h is low. These tests also indicate that monitoring of future catch-at-length ... information would be necessary to guard against a change in selectivity towards greater catches of older fish ... toothfish resource is that, while the two ‘alternative hypotheses’ above can- not at present be reliably ... best ensures that the resource is hardly likely be further depleted (and indeed preferably shows some ... data (both catch-at-length distributions and CPUEs) to be generated which are compatible with past ... compatibility with all past data is impossible, given the highly conflicting assessment results that fol- low ...

   Science Journal Paper : CCAMLR Science, Volume 16 (CCAMLR Science, Volume 16) : 33–69 : Autor(es): Brandão, A. and D.S. Butterworth

6. Age estimation and maturity of the ridge-scaled macrourid (Macrourus whitsoni) from the Ross Sea

   test. Von Bertalanffy parameters for the pooled dataset with unsexed juveniles are L ∞ 76.12, K 0.065 ... and t 0 –0.159 for males and L ∞ 92.03, K 0.055 and t 0 0.159 for females. Revised estimates of the ... formation in other deep-water rat- tails (Swan and Gordon, 2001). Spawning, and/or fasting associated with ... that growth does not appear to be statistically significant (p > 0.05) between the years within the ... precision appears to be relatively low, but these results compare favour- ably with other long-lived deep ... compared. The reduced additive model with added unsexed juveniles should be used in future analyses, as ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 291–303 : Autor(es): Marriott, P.M., M.J. Manning and P.L. Horn

7. Midwater trawl catchability in relation to krill and possible ways of assessing gross catch

   and netting and also the probability that krill will come into contact with various parts of the net ... demonstrated that the theoretical model agreed well with the real situation. Analysis of the efficiency of ... midwater trawls in the krill fishery indicates that the potential exists for this efficiency to be ... as it passes through the trawl sides. Studies were based on the results of 250 hauls made with a 72 ... and also the probability that krill will come into contact with various parts of the net as it passes ... that the theoretical model agreed well with the real situation. Analysis of the efficiency of ... midwater trawls in the krill fishery indicates that the potential exists for this efficiency to be ... , seconds hl - vertical effective fishing area of trawl with the condition that hl - ht when hl

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 87–113 : Autor(es): Zimarev, Yu.V., S.M. Kasatkina and Yu.P. Frolov

8. On the intensity of sampling krill trawl catches

   be discerned (e.g., length-with-age). At present, and in the interests of both statistical rigour and ... efficiency of measurement, it is proposed that length measurements made on commercial krill catches should be ... differences in length should be considered in conjunction with the need to collect information on maturity ... measurements of length from commercial krill;  catches should be made, as far as possible, by a single observer ... desired biological characteristics which are to be discerned (e.g., length-with-age). At present, and in ... implications associated with the detection of specific differences in length should be considered in ... that (a) studies should be undertaken to develop standardized sampling procedures for krill catches ... ANOV A procedure. From Figure 3 it can be seen that the maximum benefit in terms of detecting real ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/7 (Selected Scientific Papers, SC-CAMLR-SSP/7) : 29–48 : Autor(es): Miller, D.G.M.

9. Joinville–D’Urville Islands (Subarea 48.1) – a former fishing ground for the spiny icefish (Chaenodraco wilsoni), at the tip of the Antarctic Peninsula – revisited

   the area. Length compositions from several fishing nations revealed that the fishery targeted ... were slightly larger, with 5 Joinville–D’Urville Islands C. wilsoni fi shing ground revisited T ... (Anon., 1987). Fecundity was compara- tively low with 1 112 to 2 167 oocytes (please note that ... old. They were either immature or beginning to mature. This appears to be in agreement with ... estimates have been provided. It should be noted, however, that age determination in C. wilsoni has not ...

   Science Journal Paper : CCAMLR Science, Volume 11 (CCAMLR Science, Volume 11) : 1–20 : Autor(es): Kock, K.-H., L. Pshenichnov, C.D. Jones, K. Shust, K.E. Skora and Zh.A. Frolkina

10. Foraging behaviour and reproductive success in chinstrap penguins: the effects of transmitter attachment

    revealed that nests with both members equipped with a transmitter fared worse than both the control group ... method with which to monitor foraging trip duration in penguins by the CCAMLR (Commission for the ... 10 nests were equipped with a radio transmitter, 120 nests were used as a control group. The results ... of this study demonstrate that, for the size of transmitter used (1.4 cm 2 front section area); there ... were measured, it was revealed that nests with both members equipped with a transmitter fared worse ... recorded as the first day that a nest was observed with no chicks. A failure date of 13 January 294 ... Figures 1 and 2 shows that foraging trips appear to be slightly longer and visit durations slightly ... experiment would be worthwhile repeating with larger sample sizes. 4.2 Reproductive Success Although no ...

    Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 291–303 : Autor(es): Croll, D.A., J.L. Bengtson, P.L. Boveng, M.E. Goebel and J.K. Jansen

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