The authors present to the Working Group on Ecosystem Monitoring and Management (WG EMM) the scientific background and justification for the development of a marine protected area (MPA) in the Weddell Sea planning area. In accordance with the recommendations by WG-EMM-14 (SC-CAMLR-XXIII, Annex 6), this was done in three separate documents (Part A-C). WG-EMM-16/01 (Part A) sets out the general context of the establishment of CCAMLR-MPAs and provides the background information on the Weddell Sea MPA (WSMPA) planning area; WG-EMM-16/02 (Part B) informs on the data retrieval process and WG-EMM-16/03 (Part C) describes the methods and the results of the scientific analyses as well as the development of the objectives and finally of the borders for the WSMPA. Earlier versions of Parts A-C were already presented at the meetings of EMM and SC-CAMLR in 2015. The Scientific Committee did recognise that the body of science of the background documents (SC-CAMLR-XXXIV/BG/15, BG/16, BG/17) provides the necessary foundation for developing a WSMPA proposal (SC-CAMLR-XXXIV, § 5.11). Here, the authors present the final version of Part A to WG EMM. Part A has undergone final editorial corrections in the 2015/16 intersessional period and contains (i) a synopsis in terms of the establishment of MPAs (chapter 1); (ii) a description of the boundaries of the WSMPA planning area (chapter 2); (iii) a comprehensive, yet succinct, general description of the Weddell Sea ecosystem (chapter 3); (iv) and finally a guidance regarding the future work beyond the development of the scientific basis for the evaluation of a WSMPA (chapter 4).

Germany intends to present the Working Group on Ecosystem Monitoring and Management (WG EMM) the background document that provides the scientific basis for the evaluation of a marine protected area (MPA) in the Weddell Sea planning area. The contents and structure of the whole document reflect its main objectives, i.e. to set out the general context of the establishment of MPAs and to provide the background information on the Weddell Sea MPA (WSMPA) planning area (Part A); to inform on the data retrieval process (Part B) and to describe the results of the scientific analyses and the MPA scenario development with the directly science-based aspects of the WSMPA proposal, i.e. the objectives and the boundaries and zones of the MPA (Part C). Here, the authors intend to update WG EMM on the current state of Part A of the document that has been presented at the meeting of the CCAMLR Scientific Committee in 2014. The Scientific Committee had welcomed and endorsed the scientific background document (SC-CAMLR-XXXIII/BG/02) as a foundation reference for the Weddell Sea MPA planning (SC-CAMLR-XXXIII, § 5.21). Part A contains (i) a synopsis in terms of the establishment of MPAs (chapter 1); (ii) a description of the boundaries of the WSMPA planning area (chapter 2); (iii) a comprehensive, yet succinct, general description of the Weddell Sea ecosystem (chapter 3); (iv) and finally a guidance regarding the future work beyond the development of the scientific basis for the evaluation of a WSMPA (chapter 4). Please note that the current state of Part A of the document presents a comprehensive yet incomplete version concerning chapters that have to be (further) developed or revised.

Germany intends to present the Scientific Committee the background document that provides the scientific basis for the evaluation of marine protected areas (MPAs) in the Weddell Sea. Please note, that the current state of the background document presents a comprehensive yet incomplete first version concerning chapters that have to be (further) developed or revised. The contents and structure of the document reflect also its main objectives, i.e. (i) to set out the general background and context of the establishment of MPAs, (ii) to describe the boundaries of the Weddell Sea MPA Planning Area, (iii) to inform on the data retrieval process, (iv) to provide - for the first time- a comprehensive, yet succinct, general description of the Weddell Sea ecosystem to reflect the state of the science, and additionally to present the results of the various preliminary scientific analyses that were carried out so far within the framework of the MPA Weddell Sea project, and finally (v) to describe future work beyond the development of the scientific basis for the evaluation of a Weddell Sea MPA.

The changes in the size composition of the toothfish Dissostichus eleginoides from the long-line catches in division 48.3 (South Georgia and Shag Rocks) and determination of the length at which the males and females mature are investigated, as is the ratio between the mature and immature individuals of this species after the longterm effect of fishing. It was shown that toothfish males reach maturity at smaller lengths than females. Fifty percent of males reach maturity at length of 66–78 cm, while females mature at lengths of 78–96 cm. The ogive of toothfish maturation and its comparison with size and sexual composition of the catches in the first and last years of long-line fishing demonstrated that a significant part of immature and first maturating fishes less than 90 cm in length are removed as the result of fishing at the present time. The decrease in the average size of toothfish in the catches, the high percent of immature fishes in the catches, and the decrease of the portion of large fishes suggest a decrease in its abundance.