COMMISSION FOR THE CONSERVATION OF ANTARCTIC MARINE LIVING RESOURCES КОМИССИЯ ПО СОХРАНЕНИЮ МОРСКИХ ЖИВЫХ РЕСУРСОВ АНТАРКТИКИ CCAMLR COMMISSION POUR LA CONSERVATION DE LA FAUNE ET LA FLORE MARINES DE L'ANTARCTIQUE COMISIÓN PARA LA CONSERVACIÓN DE LOS RECURSOS VIVOS MARINOS ANTÁRTICOS CCAMLR-XXX/BG/19 24 September 2011 Original: English Agenda Item No. 12(i) SC Agenda Item No. 3(i) 30 YEARS OF KRILL FISHERIES MANAGEMENT CHALLENGES REMAIN Submitted by ASOC This paper is presented for consideration by CCAMLR and may contain unpublished data, analyses, and/or conclusions subject to change. Data in this paper shall not be cited or used for purposes other than the work of the CCAMLR Commission, Scientific Committee or their subsidiary bodies without the permission of the originators and/or owners of the data.
30 YEARS OF KRILL FISHERIES MANAGEMENT CHALLENGES REMAIN Abstract Current Antarctic krill fishing practices have been deviating from historical fishing patterns, with catches concentrated recently in certain areas such as Subarea 48.1. Based on sea-ice reduction projections, concentrated catches in Subarea 48.1 during winter are expected to occur more frequently. The reproduction and survival of krill are significantly affected by sea ice cover. This is of concern since key spawning, recruitment and nursery areas of krill are located in the Southwest Atlantic sector, an area that has been warming rapidly, resulting in a reduction in the extent and duration of winter sea ice. CCAMLR needs to maintain a precautionary approach to krill fisheries management. The establishment of CM 51-07 distributing the trigger limit among statistical subareas was a step in the right direction. CCAMLR should retain CM 51-07 to avoid concentrating the catch in one subarea as the trigger level is approached, reducing the risk of localized depletion of krill near predator colonies. Although the two-year experimental design of scientific observation produced positive results, it seems that sufficient observer data will not be obtained to allow the CCAMLR Scientific Committee to provide advice to the Commission. Thus, CCAMLR should persist in its efforts to work toward 100% observer coverage across all vessels in the krill fishery as the best way to achieve systematic observer coverage. The review of CEMP has become a high priority for the Working Group on Ecosystem Management and Monitoring. An expanded and reformulated CEMP will require new sources of funding and thus, CCAMLR will need to develop funding mechanisms, such as a dedicated CEMP Fund, to ensure the necessary resources are available. Uncertainties over green weight, krill escape mortality and the impacts of krill fishing on fish larvae continue to be a reason for concern. 1. Introduction In 2010, at CCAMLR XXIX, the Scientific Committee (SC) recognized that the management of the krill fishery is facing important challenges that still need to be resolved. Consequently, the SC decided to prioritize the work of the Working Group on Ecosystem Management and Monitoring (WG-EMM) over the next two years to focus on krill. This included: the development of feedback management; further estimations of recruitment and B 0 ; the improvement of the scientific observation scheme; the development of fishing vessel survey methods; the monitoring of catches; the issue of krill escape mortality and greenweight; and the review of the CCAMLR Ecosystem Monitoring Program CEMP. A strengthened CEMP would be fundamental for the implementation of an effective feedback management that takes into account the needs of krill predators. This paper provides an overview of current developments in the fishery and the current status of priority issues related to the management of the Antarctic krill fishery. 2. Changing fishing practices may trigger need for new spatial management Current Antarctic krill fishing practices are deviating from historical fishing patterns and becoming more of a winter fishery. The historical distribution of catches remained constant over the previous decade and for much of the history of the fishery. In recent years, however, the fishery is not only changing its temporal scale and becoming more of a winter fishery, but is also concentrating on particular sites not necessarily in line with historical fishing patterns. During the previous season (2009/2010) fishing was concentrated in the Bransfield Strait, located in Subarea 48.1. Catches were concentrated in two SSMUs (APBSW and APBSE) and they represented 80% of the total catch in the whole of Subarea 48.1. Another important element is that in 2009/10, catches from SSMUs in the Bransfield Strait in Subarea 48.1 were about 20 times greater than the average historical catch in these SSMUs.
Based on sea-ice reduction projections, concentrated catches in Subarea 48.1 during winter are expected to occur more frequently. This concentrated fishing prompted CCAMLR to endorse CM 51-07, whose closure provisions were used less than a year after adoption, at the end of October 2010 when the reported total catch of krill for subarea 48.1 reached 98.9% of the subarea catch limit (25% of the trigger level: 155,000 tonnes). This triggered the closure of the fishery in this subarea for the remainder of the fishing season. Concentrated fishing of certain life stages of krill is also of concern. Fishing in nursery areas will have a different impact on the stock than fishing in areas where adults concentrate. In some areas of the Antarctic Peninsula, young krill are known to concentrate predominantly in near-shore waters. Since younger krill aggregate in the Bransfield Strait area, the heavy fishing that occurred there last year may have a more significant impact on local krill populations than previously thought. Current precautionary catch levels were set assuming that the size selectivity of krill would remain the same as historical catches. The difference in the distribution of young krill versus adult krill (with younger krill being closer to the coast) is another factor that supports the need to move some of the fishing effort to pelagic areas. The change in size selectivity is not considered in the calculation of the catch limit, and thus it is imperative that the management of the krill fishery starts accounting for it. In the last decade, the number of vessels, as well as their catching capacity has also increased substantially. Not only do vessels using the continuous fishing system have a larger potential daily catching capacity, but also some conventional trawlers have increased their capacity (measured in tonnes of krill per day) by using two nets simultaneously and/or by improving their krill processing techniques on board. 3. Krill and climate change the need to maintain precaution The life history and demography of Antarctic krill are intimately tied to seasonal sea ice conditions, climate, and the physical forcing of ocean currents. Key spawning, recruitment and nursery areas of krill are located in the Southwest Atlantic sector. The climate in this area is warming rapidly, and as a result, the extent and duration of winter sea ice has declined. The reproduction and survival of krill are significantly affected by sea ice cover, since it has been shown that summer krill densities correlate to both the duration and the extent of sea ice during the previous winter. Accordingly, decreases in krill biomass have been observed in this area for at least the period from 1976 to 2003. In April 2011, a group of krill experts met at the Workshop on Antarctic Krill and Climate Change that took place in Texel, Netherlands. The intention of the workshop was to gather krill experts not only from CCAMLR Members but from other countries not necessarily involved in CCAMLR working group meetings. The workshop discussed krill biology in the context of climate change and the potential implications for krill fisheries management. Participants reviewed trends in agents of climate change, such as ocean warming, sea-ice decline and ocean acidification, and the potential implications for krill stocks. The workshop noted that environmental changes will act in concert to modify the abundance, distribution and life cycle of krill. In addition, it was concluded that the impact of climate change is predicted to increase considerably in the Southern Ocean over the next few decades, and that the resulting changes will likely impact negatively on krill. Among the population parameters determining the distribution and biomass of krill, recruitment, driven by the winter survival of larval and juvenile krill, was considered by workshop participants to be the most susceptible to climate change. It was also noted that the Generalized Yield Model (GYM) currently used for fisheries management does not account for trends induced by climate change, such as increased mortality and recruitment failure due to sea-ice loss. Thus, it seems inappropriate to consider stable recruitment of krill in the context of the impacts of climate change, especially in the Antarctic Peninsula and Scotia Sea area. This particular aspect should be further investigated by CCAMLR, but in the meantime, precaution should be implemented in the light of an increasing krill fishery.
Finally, the workshop concluded that climate change is adding to uncertainties that surround krill fisheries management and thus urged CCAMLR to maintain the current precautionary distribution of the trigger level in Area 48 (Conservation Measure 51-07). 4. Priority Issues for CCAMLR XXX A. The need to retain CM 51-07 - Distribution of the trigger limit among statistical subareas In order to provide some precautionary spatial allocation of krill catch limits until agreement can be reached on SSMU allocations, the Commission took a first step in 2009 and subdivided the trigger level (620,000 tonnes) resulting in CM 51-07. The main objective of this CM was to avoid concentration of the catch in sub-areas as the trigger level was approached, reducing the risk of localized depletion of krill near predator colonies. CM 51-07 was envisioned to be an interim measure, scheduled to be reviewed in 2011, to ensure the implementation of Article II, taking into account the prey requirements of land-based predators. It is important to note that the conditions under which the trigger level was established in 1991 have changed, especially the impacts from climate change, which are better understood and more significant since then. The implementation of CM 51-07 during the last fishing season (2009/10) was successful. While the CM capped the catches in Subarea 48.1, it also permitted vessels to maintain some flexibility on where to go and fish up to the actual closure of the subarea. Even after the subarea was closed fishing was allowed to continue in other subareas. The CEMP monitoring program observations did not start until October 2010, several weeks after the end of six months of fishing had concluded. As a consequence it could not offer any direct observations on the impact of fishing on krill predators whose foraging grounds overlapped with fishing effort. This situation did not allow determining if there was any ecosystem effect (negative impact on predators) as a result of concentrated krill fishing in the Bransfield Strait during the 2009/10 fishing season. In addition to this, monitoring did not include observations of mass of predators upon arrival that could have reflected the impact of fishing on predators whose foraging grounds were in overlap with fishing operations. As the fishery changes from year to year with changing ice conditions and changes in krill distribution and abundance, the monitoring program will need to be expanded, and it would help to require an indication of where the fishery will take place prior to fishing in order to assess the impacts on krill and krill predators. In the absence of this information, CCAMLR has the obligation to control fishing to reduce the potential for significant adverse impacts. There is also an urgent need for estimates on consumption by krill predators in the different areas, and new acoustic biomass assessments to get a better understanding of the spatial and temporal distribution of krill. A new synoptic krill survey would be an essential tool to conduct a revision of the distribution of krill catch limits amongst subareas. Fishing is becoming increasingly unpredictable from year to year, and thus, in order to establish an appropriate monitoring program it will be necessary to determine areas where fishing might be allowed and where monitoring related to these areas could be established before any fishing begins. In addition, krill abundance and krill predator needs estimates must also be available, prior to fishing, in order to assess the impacts derived from fishing. Taking into account that the krill fishery has large variation from year to year, the current CEMP is not able to determine impacts of krill fishing on land-based predators. As a consequence it is essential to retain CM 51-07 until sufficient information is acquired for its revision. The precautionary management measures in CM 51-07 should be maintained until an agreement on the subdivision of the overall Area 48 catch limit into SSMUs has been achieved.
B. Systematic scientific observer coverage for the krill fishery an issue still to be resolved For many years, the Scientific Committee has been advising the Commission that 100% scientific observation across all vessels in the krill fishery is the best way to achieve systematic observer coverage. A robust scientific observation program is necessary to understand the overall behavior and impact of the fishery on dependent predators and the ecosystem. In addition, such a program is the best way to collect biological data, and data on krill mortality and by-catch all factors that are currently limiting CCAMLR s ability to monitor and manage the krill fishery. In 2009, (CCAMLR XXVIII), partial scientific coverage was introduced as a requirement for the first time in the krill fishery through CM 51-06. The systematic observer coverage scheme adopted in the CM included among others, a target coverage rate of no less than 30% of vessels during the 2009/10 fishing season and no less than 50% of vessels during the 2010/11 fishing season. The purpose of this two-year experimental observer program was the collection of high-quality data, especially in the priority areas so as to understand the ecosystem effects of the krill fishery. At CCAMLR XXIX, the CM 51-06 was extended to the 2011/12 fishing season and also amended to reflect that a minimum of 50% coverage was still required. To find the best way to distribute the agreed 50% observer coverage (i.e. how to best cover areas and seasons in each subarea or division), several options were discussed at that meeting. Finally, it was decided that many fishing Members were going to implement voluntary 100% observers on board. Japan, China and Korea agreed to implement the required 50% observers on board following a scheme that was agreed during the meeting. In addition, CM 51-06 was amended to reflect the need for Members to report greenweight, and the method used to estimate greenweight. In recent years, it has been noticed that there are still some problems with regards to the lack of clarity of the definition of a haul. The definition of an observed haul is very important in the context of how CM 51-06 has been phrased. CM 51-06 calls for a coverage rate of 20% of observed hauls set by a vessel per fishing season being sampled. It is currently unclear what is meant by an observed haul : is it a haul during which a specific type of observer data was collected or simply a haul where there was an observer on board the vessel. CCAMLR needs to find a suitable definition to avoid misunderstandings. Another issue of concern is how hauls are reported in vessels using the continuous fishing system as opposed to conventional krill trawlers. If this is not more clearly defined, vessels operating the continuous fishing system and carrying 100% observers on board could end up having a lower level of observer coverage as compared to traditional fishing vessels. Consequently, CCAMLR should come up with a clear indication on the frequency of sampling for all vessels fishing for krill. In general, it appears that the two-year experimental design produced positive results, however, due to the ambiguities referred above it will not provided sufficient observer data to be analyzed by the CCAMLR Scientific Committee so as to provide advice to the Commission. In summary, at this stage it is important to come up with a clear definition of what constitutes an observed haul, indicate the frequency of sampling that will be required for all vessels, and extend the CM 51-06 for another fishing season (2012/13). CCAMLR should persist in its efforts to work toward 100% observation across all vessels in the krill fishery as it continues to be the best way to achieve systematic observer coverage.
C. The need to revise CEMP and develop feedback management CCAMLR has adopted a feedback approach to krill fisheries management. 1 Feedback management requires monitoring, assessment and decision making that allows management to be adjusted as relevant information becomes available. Such information will include assessments of krill, predators and the interactions between krill fishing and krill predators. Monitoring is central to feedback management and therefore, it cannot be properly implemented without an effective CEMP. Unfortunately, the sites monitored and the data submitted to CEMP have been decreasing in recent years. Consequently, in 2009, the Scientific Committee advised that a review of CEMP, including the requirements for its monitoring reference sites was an urgent priority. In 2010, the Scientific Committee included in the priorities for the work of the WG-EMM in the next two years the development of feedback management and the review of CEMP. This review of CEMP was in the context of ensuring that the needs of feedback management can be met. One of the first tasks for CCAMLR is to define and agree what feedback management means, the indicators to be monitored and agree on the process to be followed. The current krill fishery operating in Area 48 should represent the focus of the development of feedback management procedures. The experience gained in this area should inform the development of a much wider feedback management system taking into account that the fishery might expand to other areas. A revised CEMP is fundamental for the implementation of an effective feedback management system that takes into account the needs of krill predators. The information obtained from monitoring should provide SC-CAMLR and the Commission with the appropriate understanding that is necessary for the decision making process. In addition, as it was envisioned when CEMP was established, the production of an agreed suite of appropriate indicators is also key for the development of feedback management approaches. Therefore, it will be necessary to determine which indicators must be monitored, how (i.e. different methodologies), and where to monitor them. Having embraced the precautionary approach in managing fisheries, CCAMLR will need to adjust fishing activities (i.e. krill catch, geographical and temporal distribution) in response to the changes of monitored indicators. These indicators and the agreement on certain decision rules should constitute the basis for adjusting fishery management decisions to achieve the objectives of Article II of CCAMLR. This is of particular importance in Antarctica since in a changing ecosystem such as the Southern Ocean the only adjustment that CCAMLR can exert is through managing fisheries. CCAMLR should take advantage of all existing monitoring opportunities, using not only selected land-based monitoring sites, but also fishing and research vessels to collect data. As already recognized by WG-EMM, CEMP in its current configuration does not allow for distinguishing the impacts of fishing from those associated with environmental change, its main objective at the time of its creation. In addition, climate change could potentially induce rapid changes within the ecosystem, impacting the way indices generated by CEMP are being used to detect fisheries impacts. A revised CEMP should allow for the distinguishing of impacts from natural variability and environmental change regardless of the level of fishing. If CCAMLR decides to develop a feedback management system in Area 48 based on the current monitoring of CEMP, this would require a highly precautionary approach with regards to krill catches and/or to spatially restrict catches, focusing only in those areas where existing monitoring occurs. Areas where no CEMP monitoring exists will require establishing an extremely precautionary catch limit, until monitoring and appropriate research provides the needed information for an effective feedback management system. According to WG-EMM, in order to distinguish between climate change and fisheries impacts, it may be necessary to establish reference (control, i.e. complementary no fishing) sites and/or additional 1 (SC-CAMLR XXIX, paragraph 15.1 and Table 7).
parameters. A spatial subdivision of the fishery could be a valuable approach for the development of feedback management procedures in the krill fishery. Following this, some areas could be closed to fishing (control or reference areas), whereas in other areas fishing could be allowed, setting areaspecific catches. Comparison between no-take areas and fishing areas, if the selected areas include similar ecological features, could help assess the effects of fishing. Current CEMP sites are the result of national research programs of member countries and are not necessarily established with the intention of providing data for feedback management purposes. In many cases, research priorities respond to the need for monitoring the impact of climate change. Therefore, until CEMP is significantly reformed and expanded in its coverage, it will be very difficult to incorporate monitoring data to serve feedback management purposes. In any case, an updated CEMP should provide for the detection and attribution of change at the historical and current level of fishing. A reform of CEMP will necessarily include the establishment of new monitoring sites in areas known to be fished so as to obtain the required baseline monitoring information. Collecting baseline information on land-based predators is time consuming, and thus it would be important to ensure the continuity of current monitoring sites that have been creating relevant time data series. The CEMP revision also provides an opportunity to establish coordinated ecosystem monitoring between the ATCM s Committee on Environmental Protection (CEP) and CCAMLR s SC. At the CEP meeting in Punta del Este in May 2010 (CEP XIII), SC-CAMLR and CEP agreed to work together and consider their respective monitoring needs, and organize a second joint CEP SC- CAMLR workshop in 2012 around the theme of monitoring. An expanded and reformulated CEMP will require new sources of funding to cope with the establishment of new sites, the development of new methodologies, the analysis of data, etc. Historically, some countries, through their national programs have been covering the costs of monitoring activities. Most of these countries have not been fishing for krill and therefore, they are not benefiting from krill fishing revenues. In recent years, funding restrictions are making it increasingly difficult for those Members to continue supporting long-term monitoring. Therefore, CCAMLR should develop funding mechanisms to ensure that resources are available for an expanded, on-going monitoring program, such as a dedicated CEMP Fund. Fishing nations have a special responsibility to support a strengthened monitoring program. The creation of a dedicated CEMP Fund was also part of the advice from the krill workshop that took place in Texel in April 2011. 5. Other Issues A. Green weight a pending issue The need for a standardized reporting method for krill catches remains a pending issue in CCAMLR. An important achievement has been the amendment of CM 51-06, which now requires Members to report green weight and the method used to estimate greenweight. It also encourages Members to provide an estimate of green weight of krill caught but not brought on board. Nevertheless, the level of accuracy in estimated green weight continues to differ between methods and seasons. In addition, the methods used to estimate green weight by different Members have a variable uncertainty that current management processes are not accounting for. Therefore, it would be important to include the uncertainty level when comparing catch estimates with catch limits. CCAMLR should continue working towards a standardized green weight reporting method for krill catches. B. Krill Escape Mortality still no clear estimation exists
Krill escape mortality occurs when krill are squeezed through fishing nets, an unknown percentage of which are killed or seriously injured, without being counted as caught. In practical terms, krill escape mortality is calculated as the amount of krill escaping through the trawl mesh multiplied by the proportion of animals that die as a result of this process. Uncertainty in the level of krill escape mortality may have serious implications for assessments and catch limits, undermining CCAMLR s capacity to determine the impact of fishing operations on the ecosystem. Many different factors such as krill density, type of gear, speed of trawling, and mesh size (both on cod end and side panels) are likely to affect escape mortality. In 2009, WG-EMM recommended that a concerted effort be made to estimate escape mortality in the krill fishery. WG-EMM encouraged Members fishing for krill in 2010 to assess the effect of different fishing gears on krill escape mortality. Initial experiments conducted during the last fishing season using two different methods are still preliminary and preclude making any conclusion with regards to krill escape mortality. Only when an appropriate method is developed can the estimation of green weight be included in the routine activities of observers. An additional source of unseen krill mortality is the so-called bucket phenomenon. In this case, the pressure waves that trawl nets can produce when water cannot easily pass through the mesh (if the net is filled with krill or the trawl is being conducted at a higher speed than optimal for the particular net structure) can kill additional krill. CCAMLR Members should follow the recommendations from WG-EMM, and provide the necessary information on krill escape mortality, and participate in experimental work to estimate the level of krill escape mortality. C. Fish larvae by-catch in the krill fishery By-catch of marine larvae in the krill fishery remains an ongoing concern, especially in view of the diversity of fishing gears and methods used to catch krill. Over many years the SC has noted that there is still uncertainty over the level of by-catch of juvenile and larval fish in the krill catch over all seasons and areas in which the krill fishery operates, and from different fishing gears and fishing strategies. Of special concern is the potential level of fish larvae by-catch from demersal species, highly depleted in the late 1960s and 1970s (such as rock cod), which are still at low population levels. Determining the level of by-catch of fish larvae is very important in the management of the krill fishery since it will facilitate the assessment of the impact of krill fishing operations on non-target fish populations. CCAMLR needs to develop standardized observer protocols across krill fishing vessels to analyse by-catch of fish and other marine larvae, including a procedure for sampling fish of all sizes and species. In addition, the SC should provide advice on the acceptable level of by-catch for different fish species in the krill fishery. 6. ASOC Priority Recommendations for CCAMLR XXX ASOC urges CCAMLR to: Retain CM 51-07 until sufficient information is acquired for its revision. Extend CM 51-06 for another fishing season (2012/13), and agree on a clear definition of what constitutes an observed haul, indicating the frequency of sampling that will be required in all vessels. Develop funding mechanisms to support monitoring as necessary through a dedicated CEMP Fund.