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1. Using ecosystem monitoring data to detect impacts

   impacted by activities such as fishing. This paper discusses a range of methods for inferring such impacts ... an observed value in an unimpacted system, or (ii) the frequency of values below a fixed reference ... reference to a critical probability. All methods would have provided a sustained indication of a significant ... within a few years of its onset, but a fixed reference point method could have provided this sustained ... paper discusses a range of methods for inferring such impacts using monitoring data with no control ... system, or (ii) the frequency of values below a fixed reference point. The second approach allows ... inference criteria based on changes in this frequency rather than by reference to a critical probability ... . All methods would have provided a sustained indication of a significant decline in Antarctic fur seal ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 197–212 : Autor(es): Hill, S.L., J. Forcada, P.N. Trathan and C.M. Waluda

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

   transmitter attachment Abstract / Description:  The use of radio telemetry has been accepted as a standard ... transmitters are applied to one or both members of a breeding pair; and (iii) variability in foraging patterns ... December 1990 to January 1991 in a discrete chinstrap penguin colony composed of 666 nests on Seal Island ... 10 nests were equipped with a radio transmitter, 120 nests were used as a control group. The results ... accepted as a standard method with which to monitor foraging trip duration in penguins by the CCAMLR ... parameters when transmitters are applied to one or both members of a breeding pair; and (iii) variability ... was conducted from December 1990 to January 1991 in a discrete chinstrap penguin colony composed of ... both members of each pair at 10 nests were equipped with a radio transmitter, 120 nests were used as ...

   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

3. Estimation of krill (Euphausia superba) mortality and production rate in the Antarctic Peninsula region

   Antarctic Peninsula region Abstract / Description:  A net sampling survey for krill was carried out by RV ... abundance/biomass data exceeded a factor of 1:35, while inter-annual variability between available surveys ... reached only a factor of 1:1.6. Krill mortality was calculated by linearized catch curve analysis and ... resulted a rate of Z = 0.88 (1989/90) and Z = 0.96 (1987/88). Production was estimated and resulted a P/B ... ) MORTALITY AND PRODUCTION RATE IN THE ANTARCTIC PENINSULA REGION V. Siegel* Abstract A net sampling ... . Seasonal variation between summer and winter abundance/biomass data exceeded a factor of 1:35, while ... interannual variability between available surveys reached only a factor of 1:1.6. Krill mortality was ... calculated by linearized catch curve analysis and resulted a rate of Z = 0.88 (1989/90) and Z = 0.96 (1987 ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/8 (Selected Scientific Papers, SC-CAMLR-SSP/8) : 159–176 : Autor(es): Siegel, V.

4. Analysis and modelling of the Soviet Southern Ocean krill fleet

   as a means of understanding the within trawl and between trawl features of the operation. The data ... support the notion of a “patches within patches” model for the distribution of krill in the southern ... oceans. The second part of this document contains the development and use of a simulation model of a ... fishing operation. Parameters of the model are motivated by study of the literature and FIBEX results. A ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I (Selected Scientific Papers, SC-CAMLR-SSP/5 – Part I) : 127–235 : Autor(es): Mangel, M.

5. Methodological guidelines on the assessment of trawl catchability of krill by means of statistical modelling

   used as a basis. The Monte-Carlo method is useful for solving problems related to the quantitative ... krill fishing. However, on its own the Monte-Carlo method does not provide a complete solution to the ... set problem. This paper sets out a method of comparative assessment of the effectiveness of trawl nets ... of various configurations. The algorithm for solving this problem is constructed in such a way that ... in the works by Metropolis, N., Ulam, S. (1949) and Sobol, I. M. (1978), is used as a basis. The ... . However, on its own the Monte-Carlo method does not provide a complete solution to the set problem. This ... paper sets out a method of comparative assessment of the effectiveness of trawl nets of various ... configurations. The algorithm for solving this problem is constructed in such a way that it can be applied ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/3 (Selected Scientific Papers, SC-CAMLR-SSP/3) : 195-222 : Autor(es): Kizner, Z.I.

6. Significant intra-annual variability in krill distribution and abundance at South Georgia revealed by multiple acoustic surveys during 2000/01

   March 2001 (late-season). The surveys were the first in a newly planned five-year series of observations ... Survey since 1996 (and on a more ad hoc basis since the early 1980s). We hoped that conducting several ... from more restricted once-per-season ‘snap-shot’ cruises in a broader context. The early- and late ... transects within a box to the northwest of South Georgia. The dedicated mid-season survey covered that box ... January 2000/01 (mid-season), and in March 2001 (late-season). The surveys were the fi rst in a newly ... regularly maintained by the British Antarctic Survey since 1996 (and on a more ad hoc basis since the early ... variability that could be used to set data from more restricted once-per-season ‘snap-shot’ cruises in a ... South Georgia and were restricted to four transects within a box to the northwest of South Georgia ...

   Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 71–82 : Autor(es): Brierley, A.S., C. Goss, S.A. Grant, J.L. Watkins, K. Reid, M. Belchier, I. Everson, M.J. Jessop, V. Afanasyev and J. Robst

7. Assessing the power to detect systematic change in Adélie penguin foraging trip duration

   constructed and fitted to data collected at Béchervaise Island over a 12-year period when only natural ... per penguin. Statistics were developed to test for three forms of change (step, trend and ramp). A ... than a test based on the slope of a trending post-impact change or a joint test of difference and slope ... relax the Type I error rate to a rate well above the traditional level of 5%. The strategy of including ... trip durations were constructed and fitted to data collected at Béchervaise Island over a 12-year ... , trend and ramp). A test for change based on the difference between pre- and post-impact means generally ... performed better than a test based on the slope of a trending post-impact change or a joint test of ... unless one were willing to relax the Type I error rate to a rate well above the traditional level of 5 ...

   Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 201–215 : Autor(es): Southwell, C., J. Clarke and L.M. Emmerson

8. An alternative method for estimating the level of illegal fishing using simulated scaling methods on detected effort

   scaling methods on detected effort Abstract / Description:  A new method for estimating illegal fishing ... the number of detections for a given level of illegal fishing, the more often the illegal fishers will ... curtail their fishing trips. This leads to a negative correlation between the amount of fishing and the ... estimated amount of fishing for a given number of illegal cruises. As the number of illegal cruises ... Heritage Channel Highway, Kingston 7050 Tasmania, Australia Email – ian.ball@aad.gov.au Abstract A new ... prevention/detection problem, in which the greater the number of detections for a given level of illegal fi ... shing, the more often the illegal fi shers will curtail their fi shing trips. This leads to a negative ... correlation between the amount of fi shing and the estimated amount of fi shing for a given number of illegal ...

   Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 143–161 : Autor(es): Ball, I

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

   weight data were used to examine the power to detect a change in fledgling weights after an impact. The ... variability of fledgling weights. These models assume that data are collected during a fixed CEMP five-day ... likely to respond to resource availability as a step change represented as either a percentage increase ... year, but there was no evidence that the rate of decline differed between years. A consequence of this ... power to detect a change in fledgling weights after an impact. The statistical models were developed ... . These models assume that data are collected during a fixed CEMP five-day period corresponding to the ... availability as a step change represented as either a percentage increase or decrease after an impact ... the rate of decline differed between years. A consequence of this finding is that it may be possible ...

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

10. Marine debris and fishing gear associated with seabirds at sub-Antarctic Marion island, 1996/97 and 1997/98: in relation to longline fishing activity

    1998 is reported. Standardised searches and incidental finds show a large increase between the 1996/97 ... and the 1997/98 field seasons. Fishing gear increased at a rate 10 times higher than 'other' ... petrels. Three seabirds (a southern giant petrel, a northern giant petrel, and a sub-Antarctic skua) were ... white-chinned petrel chick and a southern giant petrel adult) were found to contain ingested fishing ... . Standardised searches and incidental finds show a large increase between the 1996/97 and the 1997/98 field ... seasons. Fishing gear increased at a rate 10 times higher than 'other' (non-fishing) marine debris over ... grey-headed albatrosses and southern giant petrels. Three seabirds (a southern giant petrel, a ... northern giant petrel, and a sub-Antarctic skua) were found entangled in fishing gear, while five seabird ...

    Science Journal Paper : CCAMLR Science, Volume 6 (CCAMLR Science, Volume 6) : 85–96 : Autor(es): Nel, D.C. and J.L. Nel

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