Climate change will alter the structure and functioning of Southern Ocean ecosystems and affect the ecosystem services they provide. The impacts of climate change will require development of conservation and management strategies that anticipate and adapt to potential changes in krill population dynamics. A recent collaborative workshop between the Integrating Climate and Ecosystem Dynamics in the Southern Ocean (ICED) programme and CCAMLR brought together a range of ecologists, physical and ecological modellers and fisheries scientists to consider the development of projections of the impacts of climate change upon krill in Area 48. Here we present the preliminary findings of this workshop: ‘Developing projections of the future state of Southern Ocean ecosystems: Incorporating uncertainties associated with climate variability and change in CCAMLR’s decision making’ held at CCAMLR Headquarters, 5-7 April 2018. The Workshop highlighted the high level of natural spatial and temporal variability of the ecosystem in Area 48. The current suite of scenarios of future changes in physical, chemical and ecological drivers across the region are highly uncertain and global climate models do not resolve ocean and sea-ice processes that are important within Area 48. As a result of that uncertainty, signals of projected changes in SST and sea-ice are not distinguishable from model variability before ~2050. Surface waters are expected to warm and sea ice concentrations reduce, but the position of the polar front is not expected to change during this century. The changes expected by the end of the century are likely to cause distribution shifts and reconfiguration of food webs, with both positive and negative effects. The Workshop highlighted our poor understanding of krill recruitment processes, the key driver of variability in krill populations across the region, and particularly their links to sea ice. It also emphasized the need for a systematic development of krill population models and high spatial resolution ecosystem models. The Workshop noted the importance of developing a joint approach between ICED and CCAMLR to improve scenarios and ecosystem models and develop quantified model projections of ecosystem change in support of decision making for conservation and management. A final version of the report and agreed statements will be submitted as a Working Paper for consideration at SC-CAMLR-XXXVII.
Abstract:
The previously presented document at the 2018 ASAM WG meeting (ASAM-18-07) described a design and plans for a synoptic krill acoustic survey in CCAMLR area 48 in 2019. The survey involves the collaborative efforts of Norway, Association of Responsible Krill fishing companies (ARK: companies from Norway, Korea, China and Chile), the United Kingdom, Ukraine, Korea and China, all of whom have confirmed a commitment of survey ship time. With these commitments it is feasible to implement all transects occupied during the 2000 survey. This document is a draft survey manual, produced at the recommendation of the 2018 ASAM meeting, and describes acoustic procedures, acoustic reporting - analysis procedures and contingency plans.
Abstract:
The estimates of fur seal consumption of krill in subareas 48.1 to 48.3 which have been used in ecosystem modelling and CCAMLR’s risk assessment approach, are based on the distribution of fur seal breeding populations. Fur seal breeding colonies south of 60o have remained relatively small and their biomass is orders of magnitude less than those of penguins. As a result the estimates of fur seal consumption outside of the South Georgia region, where ~95% of the population breeds, are relatively insignificant. However evidence from the growing body of tracking data has revealed the importance of the South Orkneys and Peninsula regions to male fur seals during their post mating dispersal from breeding sites on South Georgia. Using a combination of published and BAS data we highlight the potential importance of this connectivity. Our estimates suggest that the influx of fur seal males from South Georgia has a significant impact on the marine environment around the South Orkney Islands with a potential total krill consumption of approximately 86,500 tonnes. This is very likely an underestimate as it is based on a census of the fur seal population at South Georgia from 1991 which represented a year of poor environmental conditions. This population has also undoubtedly grown since this count. Our estimates also do not account for the need of male fur seals to recover condition during this time after fasting during the mating season and a number of important data gaps exist. We recommend further detailed analysis is prioritised in order to provide more robust estimates of the fur seal impact on this region that can be used to inform management, including through the risk assessment framework.
Abstract:
Age information for commercial fish species is crucial to fishery management. Age information for Antarctic krill (Euphausia superba) will be important for stock assessment modeling and future feedback management of krill fisheries. Samples stored in 70% ethanol provide an opportunity to detect the growth bands of eyestalk sections. Moreover, information derived from samples preserved in formalin will have a greater impact on the feedback management process because this preservation method was more common in previous decades. Out of 162 Antarctic krill individuals preserved in 5% formalin, the growth bands from eyestalk sections of 134 samples were readable. The relationship between the total length and the growth bands in the eyestalk was analyzed. Three main parameters, including exact percent agreement (EPA), coefficient of variation (CV), and average percentage error (APE), were used to evaluate the precision of the growth bands.Results show decreased CV and APE values and an increase in the EPA value with the accumulation of reading runs. The estimated VBFGs were expressed as Lt=60.50*(1-e-0.50*(t-0.45)) for males and Lt=69.59*(1-e-0.25*(t+0.58)) for females, respectively (note: those infromation were not including published paper). This method is direct and uses a grinding and polishing technique before reading, contrary to Krafft et al. (2016) and Kilada et al. (2017). Combined with published studies, specimens collected from autumn to winter in this study can provide a better understanding of Antarctic krill growth. This study presents important information for age determination, particularly for specimens preserved in formalin, and will benefit the stock assessment and acoustic estimation of this species in the future. Further studies are required to validate the correlation between growth bands and age. Additionally, more samples from different seasons and regions are also needed to fully understand the growth dynamics of this species.
Abstract:
The aim of the ECOgaps is to improve the knowledgebase on physical conditions and biota east of the 0 meridian in the MPA planning Domain 4. Focusing on the Astrid ridge, the continental shelf off of Dronning Maud Land, and the Maud rise, multidisciplinary investigations will be conducted in 2019 by the RV Kronprins Haakon. In this working document, the cruise being planned is outlined. Aims and activities of the six scientific work-packages of the project are described.
Abstract:
The RAPID-KRILL project is funded by the Antarctic Wildlife Research Fund to develop at-sea automated processing of acoustic data on fishing and research vessels. An update on the project progress is presented here, including an overview of the data processing methods.
Abstract:
The primary objective for this project is to develop knowledge on the marine environment essential for the implementation of a Feed-Back Management (FBM) system. In terms of FBM, Marine Protected Area (MPA) development in CCAMLR Planning Domain 1 encompasses the major krill fishing grounds. Thus, data supporting FBM as an integral part of the broader management strategies of the krill fisheries within Domain 1 are critical if the fishery is to be managed by an empirical understanding of krill density, distribution, availability and predator needs. A future developed FBM system, as presented in SC-CAMLR XXXVI/BG20 requires acoustic data to be collected, processed and reported continuously during the fishing season as a measure of the available prey field. This information can be integrated with finer-scale knowledge of krill predator feeding strategies and updated through specific scientific studies at regular (multiyear) intervals. The FBM process studies will take place during the Austral summer 2018-2019.
Abstract:
There is increasing interest in using higher-trophic level predators as ecosystem indicators because their performance is presumed to be linked to the overall function of the ecosystem that supports them. In the southwest Atlantic sector of the Southern Ocean, Antarctic krill (Euphausia superba) supports huge predator populations as well as a growing commercial fishery. To utilize information from the ecosystem in an adaptive framework for sustainably managing krill catch levels, performance indices of krill predators have been proposed as a proxy for krill abundance. However, there are several potentially confounding sources of variability that might impact predator performance such as the effects of environmental variability and fishing pressure on krill availability at scales relevant to predators. In this context, our study capitalises on the occurrence of an unexpected El Niño event to characterise how environmental variability can drive changes in predator foraging behaviour. We demonstrate a clear link between coastal downwelling and changes in the at-sea habitat usage of chinstrap penguins (Pygoscelis antarctica) foraging in a local krill fishing area. Penguins tracked from their breeding colonies on Powell Island, Antarctic Peninsula, undertook fewer, longer foraging trips during the downwelling-affected season compared to the season where no such downwelling was detected, suggesting that changes in climate-driven oceanography may have reduced krill availability along the northern shelf of the island. Our study demonstrates that penguin foraging behaviour is modified by scale-dependent processes, which if not accounted for may result in erroneous conclusions being drawn when using penguins as bioindicators of krill abundance.
Abstract:
We aim to investigate the qualitative changes in the habitats of two most common species penguin populations in the Wilhelm Archipelago Pygoscelis papua (gentoo) and Pygoscelis adeliae (Adelie) penguins in the CCAMLR Subarea 48.1 under the impact of climate changes and krill fishery. To minimize the effect of human disturbance on the breeding success and survival of chicks and avoid disturbance to the penguins, the new method of registration using time-lapse cameras have been installed in the penguin colonies for observation breeding success of penguins: arrival to colony, copulation, egg lay, hatch, and creche, has been applied. This method was introduced for the first time in the framework of international CEMP project “Establishing a CEMP Camera Network in Subarea 48.1”. The project timeline is expected more than five years. The traditional visual observation of biologists from time to time has been used as well. Changes in the penguin species habitat have been observed on the territory of the Wilhelm Archipelago. It was observed that at the beginning of the ХХІ century the nesting areas of P. papua was significantly extended probably due to the climate warming in the region. It was shown that P. papua is more ecologically plastic species than P. adeliae. Well-known that the breeding success of penguins can be used as an indication of the status of lower trophic levels. Future development of the penguin nesting colonies monitoring using the CEMP Camera Network under the CCAMLR supervising will contribute significantly to the real-time estimates of relative prey availability. The results of the gentoo and Adelie penguin’s chronology and breeding success studies might be used in the development of the krill fishery management strategy in the CCAMLR for the rational use of Antarctic marine living resources; (2) to develop a resettlement model to predict the ecological risks due to climate changes for both penguin species.
Abstract:
An initiative to support research and monitoring of the Ross Sea Region Marine Protected Area (RSRMPA) through satellite tagging and otolith microchemistry of Antarctic toothfish (Dissosticus mawsoni) within the RSRMPA is proposed. The objectives of this initiative are twofold. The first is to deploy a total 20 pop-off satellite tags (PSAT) on juvenile toothfish within the General Protection Zone (GPZ(i)), as well as adult toothfish the northern seamounts associated with the Pacific Antarctic Ridge. The PSAT component will provide insight into movements between various regions of the Ross Sea, potentially including different zones of the RSRMPA, and vertical movements in the water column. The otolith microchemistry component is designed address key gaps in relation to the Ross Sea Antarctic toothfish life history hypothesis and relationships to the RSRMPA. This includes whether D. mawsoni on the Ross Sea shelf contribute to adult aggregations over the Pacific Antarctic Ridge, and whether ecosystem services are provided in the form of fish exported from the RSRMPA GPZ(i) to habitats downstream. This initiative is dependent on CCAMLR endorsing the proposed continuation of the Ross Sea shelf survey to monitor abundance of Antarctic toothfish in the southern Ross Sea in 2018/19 (Stevens et al., 2018), and a winter longline survey of Antarctic toothfish in the northern region of Subareas 88.1 and 88.2 (Delegation of New Zealand, 2018).