TH REPORT OF THE 24 SCIENTIFIC COMMITTEE MEETING 13-17 NOVEMBER 2017 © North Atlantic Marine Mammal Commission NAMMCO SC/24/Report Please cite this report as: NAMMCO 2017. Report of the 24th Scientific Committee meeting, 14-17 November 2017 2 NAMMCO SC/24/Report NAMMCO SCIENTIFIC COMMITTEE 24TH MEETING REYKJAVIK, ICELAND 14-17 NOVEMBER 2017 EXECUTIVE SUMMARY The 24th meeting of the NAMMCO Scientific Committee was held 14-17 November 2017 at the Marine Research Institute in Reykjavik, Iceland. The Chair, Dr Tore Haug (Institute of Marine Research, Norway) opened the meeting by welcoming the participants. The Chair noted that all NPRs had been received from member countries, although some were still lacking the catch reporting. The SC was informed that Council had agreed to request all NPRs to be submitted before 1 March in any year. The SC saw this as beneficial as it will make the reports more relevant for the discussions of the SC meetings. Reports were available from 3 working groups (WGs; Large Whale Assessment Working Group, NAMMCO- JCNB JWG, and the By-catch WG) for the SC’s consideration, and were discussed in detail under the relevant agenda items. The full reports are available in Annex 1-3. Work Procedures in the SC The SC was updated on decisions made by Council at NAMMCO-25 on the participation and funding of External Experts, confidentiality of documents, and new requests for advice. The SC discussed R-1.6.4 (advice on the best methods for collecting struck and loss data) and noted that they responded to this request at the last meeting stating that using observers at the different hunts would be the optimal solution as struck and lost (S&L) rates vary between hunts and species. Council at NAMMCO 25 noted that this would be logistically and financially challenging. The SC further noted that better S&L rate data may not always be the priority parameter for improving assessments, given the difficulty of obtaining such data. However, given the importance of identifying S&L rates for some hunts more than others, it was agreed that one way forward was to direct WGs to indicate when more reliable S&L were a priority for improving the assessment and would make the most significant difference in terms of quota allocation, so the collection of S&L data could be prioritised for these hunts. The WG could then give recommendations on how to better obtain S&L data for the targeted hunts. The SC also noted the importance of informing hunters that uncertainty of S&L rates could result in lower quota, as precautionary rates are used, whereas reliable observed rates could decrease the uncertainty around population trajectories. Super-Satellite Tag Proposal The SC discussed the proposal by Heide-Jørgensen (Greenland) for development of a super-satellite tag. The project which is three fold entails a) the technical development of the tag, b) a programme to study movements and changes in occurrence of common minke whales in the North Atlantic and c) a shared NAMMCO data base of tracking data. The SC welcomed the proposal and agreed to recommend to Council to prioritise such cooperative projects and asked for approval to work towards such a project. The SC agreed that a small group of SC members (led by Heide-Jørgensen) should either meet in person or via correspondence to discuss the steps to move forward with the proposal. The SC discussed that it might be useful to engage other interested parties in the development of a new “common minke satellite-tag”, so the cost of the development could be shared. Working Procedures for Management Advice Prewitt presented document SC/24/16: “Summary of assessment and working procedures in the SC and associated WGs.” The purpose is to render transparent the management advice process, and, where possible and desirable, streamline the process and make it more consistent between WGs. Alternatively, it would also clearly identify areas where certain WGs have different procedures 3 NAMMCO SC/24/Report The SC agreed that for the purpose of transparency such an overview is important. The aim is not to standardise the rules for how decisions are made, but to have a systematic overview giving the rationale behind specific decisions, and as a result also an historic recording of how decisions are taken for the future. The SC noted that this was a working document and agreed to give their input to the Secretariat. SWOT Analysis As input to the current strategy and capacity building discussion evolving in NAMMCO, SC members were asked to provide a SWOT analysis of the SC (Strengths, Weaknesses, Opportunities and Threats). Members were asked to fill in the distributed template, which will then be collated by the Secretariat. Cooperation With other Organisations The SC heard updates on cooperation with the Scientific Committee of the International Whaling Commission (IWC), Agreement on the Conservation of Small Cetaceans in the Baltic, North East Atlantic, Irish and North Seas (ASCOBANS), International Council on the Exploration of the Seas (ICES), the Joint Commission on Narwhal and Beluga (JCNB), and the Arctic Council. Full reports can be found in Appendix 4. Environmental/Ecosystem Issues Consumption of resources by marine mammals Skern-Mauritzen presented the project “Exploring marine mammal consumption relative to fisheries removal in the Nordic and the Barents Seas.” The project reviews and summarises the currently available information on diet, abundances, and residence times of marine mammals in the Nordic and the Barents Seas, and follow recently recommended approaches to estimate plausible ranges of total consumption, and also compares marine mammal consumption to removal by fisheries (retrieved from ICES databases). Preliminary results suggest that marine mammal consume around 15 million tons ± 50% of prey per year, predominantly targeting low and mid trophic level species (zooplankton and small pelagic fish). Fisheries remove around 4.3 million tons per year, targeting mid and top trophic levels (small pelagic fish and larger demersal and pelagic fish). The SC welcomed this joint initiative and noted that there is a lot of NAMMCO participation in this project. Important areas for NAMMCO are covered by this project, and the SC looks forward to seeing the published results. Foraging studies Haug reported from a recent study of selection and foraging response of harbour seals in an area (Porsangerfjord, Finnmark, Norway) of changing prey resources (Ramasco et al 2017). The foraging behaviour of seals was investigated by assessing their preference and foraging response to the seasonal dynamics of prey distribution. Small codfish were preferred during autumn, but a response to the presence of pelagic fish was seen when the latter aggregated to overwinter in cold deep waters in the inner parts of the fjord. The formation of ice during late winter, however, provoked a shift in preference for small codfish, due to the sudden inaccessibility of pelagic fish. A strong reversed trend was observed in spring when the ice melted. The results indicate preference for small aggregated fish and the presence of a foraging response to changes in resource distribution. Furthermore, Haug reported on trophic levels and fatty acids in harp seals compared with common minke whales in the Barents Sea (Haug et al. 2017a). The stable isotopes and fatty acids indicated niche separation between the seals and the whales, and between different age groups of the harp seals. Older seals had fatty acid profiles more equal to common minke whales as compared with younger seals. Furthermore, while the fatty acid profiles suggested that krill was particularly important for the young seals, the profiles from older seals and whales suggested that fish dominated their diets. Future work Haug also reported that a high priority part of the planned Joint Norwegian-Russian Research Program on Harp Seal Ecology is to deploy satellite transmitters on harp seals in the White Sea. 4 NAMMCO SC/24/Report By-catch Desportes presented the report of the By-Catch Working Group (BYCWG) met from 2-4 May 2017 in Copenhagen, Denmark, under the chairmanship of Kimberly Murray, Northeast Fisheries Science Center – NOAA, USA. The Terms of Reference for the meeting were: 1. Review the Norwegian harbour and grey seals and harbour porpoise by-catch data and estimates; 2. Review the Icelandic lumpfish and cod gillnet fishery by-catch data and estimates; 3. Review the situation in the Faroese mid-water trawling - precise fleet description, by-catch risk and reporting; methods for improving the situation; 4. Review the information from Greenland on reporting of by-catch for the different species. By-catch estimate of harbour porpoise, grey and harbour seals Norway The WG reviewed the three methods of by-catch estimation, a stratified ratio-based and a model-based approaches, as well as a mark-recapture approach for seals. The WG identified several important issues associated with the three approaches, both with the data acquisition through the coastal reference fleet and the analyses used for extrapolating the observed by-catch rate to the fisheries, which prevented it from endorsing the proposed by-catch estimates. The group recommended methodological improvements to be implemented both in the data collection and the analysis before the by-catch estimates could be endorsed. The recommendations of the BYCWG are being addressed by current work by IMR in conjunction with the Norwegian Computing Center. There are plans for a student to begin working in early 2018 on revising the estimates, pending funding from Research Council. These estimates are needed for the Harbour Porpoise WG (expected fall 2018) and Coastal Seals WG (expected 2019). Iceland The Working Group identified several issues with the analysis, and provided the recommendations for revising the analysis of by-catch estimates to be addressed before it could endorse the estimates, as well as improving the data collection.