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1. On the power to detect changes using the standard methods for monitoring parameters of predatory species

   to the study, the mean number of chicks raised to creche age per pair was 1.26, with a standard deviation ... a change of magnitude equal to 0 in the mean number of chinstrap chicks raised to creche age per breeding ... , age at first reproduction, and cohort strength. The banding program in "Method A" will provide ... estimates of the average survival of adult breeding birds. "Method B" will provide age-specific survival ... Paper Title:  On the power to detect changes using the standard methods for monitoring parameters ... of predatory species Abstract / Description:  The CCAMLR guidelines (CCAMLR, 1989) for analyzing the ... considered here are insufficient for conducting power analyses (penguin arrival weight A1.1, trend in penguin ... population size A3.1, penguin demography A4.1, penguin fledging weight A7.1). Alternative forms for analyses ...

   Science Journal Paper : Selected Scientific Papers, SC-CAMLR-SSP/6 (Selected Scientific Papers, SC-CAMLR-SSP/6) : 377–397 : Author(s): Boveng, P. and J.L. Bengtson

2. Improving estimates of Adélie penguin breeding population size: developing factors to adjust one-off population counts for availability bias

   the breeding site prior to the reference point because their breeding attempt failed, breeding-age penguins ... to the reference point because their breeding attempt failed, breeding-age penguins that failed to return ... attempt failed, breeding-age penguins that failed to return to the breeding site in that breeding season ... site prior to the reference point because their breeding attempt failed, breeding-age pen- guins ... 0. 0 0. 5 1. 0 1. 5 2. 0 0 20 40 60 80 10 0 Camera 2 16 1 Nov 16 1 Dec 16 1 Jan 16 1 Feb 16 ... 0. 0 0. 5 1. 0 1. 5 2. 0 0 20 40 60 80 10 0 Camera 3 A du lt A va ila bi lit y A dj us tm en t F ac to r 16 ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 229–241 : Author(s): Southwell, C., J. McKinlay, L. Emmerson, R. Trebilco and K. Newbery

3. The biology, ecology and development of fishery management advice for the anomuran crabs at South Georgia (CCAMLR Subarea 48.3)

   crabs at South Georgia (CCAMLR Subarea 48.3) Abstract / Description:  This review summarises ... This review summarises the available information on the biology and ecology of the lithodids ... and Vinuesa, 1999) and enters the fishery at an approximate age of 15 years (Lovrich, 1997). Reproduction ... crustaceans, estimating age and growth rate of the lithodids is problematic. The lack of persistent hard ... to otoliths in fish or statoliths in cephalopods, that record age or growth. In addi- tion, it is very hard ... to resolve age–length cohorts within length-frequency data (i.e. Purves et al., 2003), which appear ...

   Science Journal Paper : CCAMLR Science, Volume 19 (CCAMLR Science, Volume 19) : 1–15 : Author(s): Belchier, M., T. Peatman and J. Brown

4. Scientific observations in CCAMLR fisheries – past, present and future

   and they operate on vessels under fl ags other than that of their own country. This paper outlines the history ... Member serves on a vessel fl ying the fl ag of another Member). Designating Members appoint scientifi ... of the efficiency of mitigation measures. Medium Collection of fish scales and otoliths for age determination ... ) samples of birds for age and species identification. Low The estimation of the number of fish per haul ... / Description:  CCAMLR has the primary competency for managing fishing south of the Antarctic Polar Front ... observers on board fishing vessels has assumed prominence in the collection of essential data for fisheries ... designed to gather and validate fishery-related information essential for assessing the status of target ...

   Science Journal Paper : CCAMLR Science, Volume 12 (CCAMLR Science, Volume 12) : 81–98 : Author(s): Sabourenkov, E.N. and E. Appleyard

5. Demographic characteristics of the Adélie penguin population on Béchervaise Island after 12 years of study

   after 12 years of study Abstract / Description:  Demographic parameters (age-specific survival rates ... Demographic parameters (age-specific survival rates, fecundity levels and population numbers) were ... in eastern Antarctica after 12 years of monitoring under the CCAMLR Ecosystem Monitoring Program (CEMP ... Demographic characteristics of the Adélie penguin population on Béchervaise Island after 12 years ... probabilities of detection (>90% of penguins that survive to 6 years of age have been resighted by age 4 years ... since Adélie penguins elsewhere have been shown to live up to 20 years of age (Reid, 1968; Ainley et ... in female Adélie penguins fi rst occurs between 3 and 7 years of age and fecundity is known to increase ... with age up to 7 years (Ainley et al., 1983). The mean number of chicks crèched per breeding female aged ...

   Science Journal Paper : CCAMLR Science, Volume 10 (CCAMLR Science, Volume 10) : 53–74 : Author(s): Clarke, J., L.M. Emmerson, A. Townsend and K.R. Kerry

6. Movement, growth and available abundance to the fishery of Dissostichus eleginoides Smitt, 1898 at Heard Island, derived from tagging experiments

   (approximately 80 mg Sr per kg of fi sh) to mark their otoliths for later verifi cation of the age- reading ... nd s an d th e m ov em en ts o f t ag ge d fi sh b et w ee n th em . O ce ... . Such results serve as a useful check on the von Bertalanffy growth parameters calculated from age and length ... is proportional to the vulnerability to fi shing of that size class. Consequently, every released fi sh is aged ... for the management of toothfish stocks and that trends in abundance derived from these experiments ...

   Science Journal Paper : CCAMLR Science, Volume 9 (CCAMLR Science, Volume 9) : 33–48 : Author(s): Williams, R., G.N. Tuck, A.J. Constable and T. Lamb

7. Length-based assessment for mackerel icefish (Champsocephalus gunnari) at South Georgia

   to set a two-year total allowable catch (TAC). One issue is the accurate identification of age cohorts ... model (GYM) packages, which derives population numbers-at-age and projects these numbers forward under ... identification of age cohorts from the survey data. In this paper a length-based approach is described ... . A comparison of this method and the existing age-based CMIX/GYM methodology showed very good agreement ... -year TAC), will be in a length- not an age-structured paradigm. In such a length-based assessment ... , not age. With length- based models, animals make transitions between elements of the length-partition ... density-at-age. To fully explore the potential utility of the pro- posed method as a new assessment ... 2+ animals with considerable uncertainty in the age structure generated by CMIX (SC-CAMLR, 2008 ...

   Science Journal Paper : CCAMLR Science, Volume 17 (CCAMLR Science, Volume 17) : 129–137 : Author(s): Hillary, R.M., C.T.T. Edwards, R.E. Mitchell and D.J. Agnew

8. An index of per capita recruitment

   recruitment (PCR) is proposed such that where R 1 is the proportion of age-l animals sampled in year ... that: (i) post-recruit mortality does not vary over age or between years; (ii) 100% of age-l animals spawn; (iii ... to recruits per spawner when mortality is constant over all ages and years, and when all age-l animals spawn ... years; (ii) 100% of age-l animals spawn; (iii) a representative sample of the population is available ... is the proportion of age-l animals sampled in year y and M is the post-recruit mortality rate. The intent ... or between years; (ii) 100% of age-l animals spawn; (iii) a representative sample of the population ... is constant over all ages and years, and when all age-l animals spawn. These conclusions are insensitive ... spawn and to 0.266 if no age-2 animals spawn. Age7 219.36 Year-to-year random variability ...

   Science Journal Paper : CCAMLR Science, Volume 7 (CCAMLR Science, Volume 7) : 179–196 : Author(s): Hewitt, R

9. Length-based assessments revisited – why stock status and fishing mortality of long-lived species such as toothfish cannot be inferred from length-frequency data alone

   with other informative estimators for stock abundance and productivity, the review and the simulations ... with other informative estimators for stock abundance and productivity, the review and the simulations ... . 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Immature selectivity Age (y) Se le ct iv ity ... 0 10 20 30 40 50 0. 0 0. 2 0. 4 0. 6 0. 8 1. 0 Truncated mature selectivity Age (y) 0 10 20 30 ... assumed a single population without movement or migration. It represented age classes from 0 to 50 years ... the age of 4 years and the age of 50% maturity (‘immature selectiv- ity’). This fishing selectivity ...

   Science Journal Paper : CCAMLR Science, Volume 18 (CCAMLR Science, Volume 18) : 57–73 : Author(s): Ziegler, P.E., D.C. Welsford and A.J. Constable

10. A first step towards modelling the krill–predator dynamics of the Antarctic ecosystem

    to the hypothesis of a krill surplus in the mid-20th century is described, and the information on population ... surplus in the mid-20th century is described, and the information on population and trend levels that has ... that support this ‘surplus’ krill hypothesis. The estimated trend in age-at-maturity of minke whales ... ., 1999; Zenitani and Kato, 2005). Analyses of catch-at-age data using the ADAPT-VPA method (Butterworth ... the same period (Ash, 1962). Bengtson and Laws (1985) suggest a similar trend in the age-at-sexual ... crabeater seals, and showed a drop in the age-at-sexual-maturity from the 1959 to the 1963 cohort ...

    Science Journal Paper : CCAMLR Science, Volume 13 (CCAMLR Science, Volume 13) : 217–277 : Author(s): Mori, M. and D.S. Butterworth

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