SAON CANADA SCIENCE - POLICY BRIEFS

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1 SAON Canada- CPC Sciencepolicy briefs SAON CANADA SCIENCE - POLICY BRIEFS May 2015 Volume 1, Issue 6 Sustaining Arctic Observing Networks (SAON) Canada, in partnership with the Canadian Polar Commission, is collaborating with the Association of Polar Early Career Scientists (APECS) to present results of monitoring efforts in the Canadian North, including the Yukon, Northwest Territories, Nunavut, Nunavik and Nunatsiavut.

2 - 1 - V 1.6 May 2015 CONTENTS Implications of forest fire frequency on black spruce regeneration in northern Yukon Community-based monitoring in the Beaufort Sea: Climate change impacts beluga health and food security for Inuvialuit communities Aerial surveys update narwhal management guidelines for Eastern Canadian Arctic Ice islands in the Canadian Arctic: Implications for shipping and offshore operations

3 - 2 - IMPLICATIONS OF FOREST FIRE FREQUENCY ON BLACK SPRUCE REGENERATION IN NORTHERN YUKON Summary Fire can occur both naturally and as a result of human activities in the northwestern Canadian boreal forest. Climate change is expected to create warmer conditions that favour an increase in the frequency of forest fires, which may impact succession in black spruce forests. Researchers from the University of Saskatchewan and Memorial University have been investigating black spruce regeneration following forest fires near the boreal treeline in northern Yukon and interior Alaska. Black spruce stand regeneration is strongly linked to viable seed stock, which is dependent on tree age and size. Results demonstrate that the regeneration of black spruce forests can be hindered when forest fires recur at intervals of less than 50 years. More frequent fires may result in a shift from coniferous to broadleaf forests and grass-dominated communities. It may reduce forest carbon storage and affect climate feedbacks. These results can inform local and regional policies regarding fire suppression and post-fire replanting, including Yukon Wildland Fire Management policies. CONTEXT: Historically, fire has occurred naturally in the western boreal forest, approximately once every 100 years, and many tree species have adapted to this cycle. 1 In northern Yukon and interior Alaska, black spruce is a dominant conifer species that relies on this fire cycle for regeneration. As climate change is expected to lead to more frequent and severe fire events in the northern boreal forest, 1,2,3 there is concern that black spruce may be vulnerable to a shorter fire-return interval. 1,4,5 Black spruce forests are a valuable resource for subsistence species that are important for Northerners. Black spruce can reproduce through serotiny. This adaptive response involves the release of a large amount of seed following a trigger event, such as a fire, which facilitates stand replacement. Researchers from the University of Saskatchewan and Memorial University have been studying the boreal treeline in northern Yukon since This was supported under Canada s International Polar Year (IPY) program, and monitoring of disturbance impacts on treeline regeneration has continued through the recently launched Global Treeline Range Expansion Experiment (G-TREE) 6 in the Yukon and across Canada. Researchers studied post-

4 - 3 - V 1.6 May 2015 fire regeneration of black spruce through seed and cone counts and seeding experiments at sites in northern Yukon and central Alaska with varying histories of fire. 1,5 RESULTS & IMPLICATIONS: Researchers selected sites with varying histories of fire in northern Yukon and central Alaska in order to investigate black spruce regeneration near the treeline following a fire. Sites that were recovering from a recent fire following a long (~94 year) fire-free interval had significantly more black spruce seedlings than sites having experienced two fires during a short interval (14-15 years) or mature sites that had been fire-free for ~77 years year old black spruce were only 50% likely to produce seed-bearing cones. This increased to 90% in trees 100 years and older. 5 Researchers concluded that fire intervals of less than 50 years impede black spruce stand regeneration following a fire in which most or all vegetation is destroyed (stand-replacing fire). 1,5 Black spruce maturity at the time of fire is the key determinant of stand replacement after fire. 1,5 When fire intervals are shorter than 50 years, black spruce forests are vulnerable to shifts in plant communities to broadleaf and grass-dominated communities. 1,4,5 While the range expansion of boreal species is expected in a warmer climate, increased fire frequency may in fact limit the regeneration of black spruce near the treeline in Yukon. 1 POLICY LINKAGES: Increased forest fire frequency may result in a shift from forest-dominated to broadleaf or grass-dominated communities. This research can inform climate models as changes may affect carbon budgets through a decrease in carbon storage and impact climate feedbacks at the ecosystem level through changes in albedo and permafrost. This research improves understanding of the vulnerability of black spruce forest regeneration and can inform local and regional Yukon Wildland Fire Management policies regarding fire suppression and post-fire replanting. REFERENCES: 1. Brown, C.D. & Johnstone, J.F. (2012). Once burned, twice shy: Repeat fires reduce seed availability and alter substrate constraints on Picea mariana regeneration. Forest Ecology and Management 266, Flannigan, M., Cantin, A.S., de Groot, W.J., Wotton, M., Newbery, A., & Gowman, L.M. (2013). Global wildland fire season severity in the 21 st century. Forest Ecology and Management 294,

5 Gustine, D.D., Brinkman, T.J., Lindgren, M.A., Schmidt, J.I., Rupp, T.S., & Adams, L.G. (2014). Climatedriven effects of fire on winter habitat for caribou in the Alaskan-Yukon Arctic. PLoS ONE 9(7): e doi: /journal.pone Buma, B., Brown, C.D., Donato, D.C., Fontaine, J.B., & Johnstone, J.F. (2013). Bioscience 63, Viglas, J.N., Brown, C.D., & Johnstone, J.F. (2013). Age and size effects on seed productivity of northern black spruce. Canadian Journal of Forest Research 43, Brown, C.D., Mamet, S.D., & Trant, A.J. (2013). The global treeline range expansion experiment. Cirmount 7(2), 6-7. Author: Sarah Quann, MSc, Carleton University

6 - 5 - V 1.6 May 2015 COMMUNITY-BASED MONITORING IN THE BEAUFORT SEA: CLIMATE CHANGE IMPACTS BELUGA HEALTH AND FOOD SECURITY FOR INUVIALUIT COMMUNITIES Summary Beluga whales are an important part of the Inuvialuit diet. Various factors, including climate change, may have implications on the health, contaminant concentrations, habitat use (movement of beluga whales), and nutritional quality of beluga whales. For over three decades, Inuvialuit communities have been monitoring beluga whales in collaboration with Fisheries and Oceans Canada (DFO) and the Fisheries Joint Management Committee (FJMC). Dr. Lisa Loseto and her team at DFO have been working for the Hendrickson Island Beluga Program, conducting research on beluga diet, contaminants exposure including mercury, and links to ecosystem health and stressors. Data demonstrate a change in hunting seasonality as well as a decrease in beluga growth rates and blubber thickness. Beluga mercury concentration levels increased in the 1990s, but have since declined; the temporal trends are not related to mercury emissions. The ecosystem is complex and changes are affecting the belugas and their supporting ecosystem. This monitoring initiative provides important baseline data from which to evaluate changes in beluga and ecosystem health as a result of climate change within the Tarium Niryutait Marine Protected Area. Results can inform management options that can be taken by DFO, together with the FJMC, in this to ensure the viability of the population and the preservation of hunting for Inuvialuit. CONTEXT: Beluga whales are an important part of the diet of Inuvialuit communities in the Western Arctic 1,3,4. Several factors can affect the nutritional quality, health, contaminant concentrations, and movement of belugas. For example, climate change is affecting sea ice extent and dynamics, which in turn affects the presence of Arctic cod the main prey for Changes in ice dynamics as a result of climate change can impact the movement of Arctic cod and their nutritional quality for beluga whales. belugas 1,5. An ecosystem approach is necessary to understand the complex relationships at play. Since the 1970s, Inuvialuit communities along the Beaufort Sea have worked collaboratively with scientists from Fisheries and Oceans Canada (DFO) and with the

7 - 6 - Fisheries Joint Management Committee (FJMC) under the Hendrickson Island Beluga Program to study beluga whales 1. Data collected include, but are not limited to, hunting efficiency, amount of whales harvested, whale morphometrics (i.e., age, sex, size), blubber thickness, and tissue samples. The program was modified to include intensive beluga health monitoring in the 1990s 3,4. RESULTS & IMPLICATIONS: Under the Hendrickson Island Beluga Program, Dr. Lisa Loseto and her team from the Freshwater Institute at DFO have been focusing on beluga diet, contaminants exposure, beluga health and links to ecosystem health and stressors. Key results demonstrate the following: Sea ice breakup is occurring earlier in the spring 10, which affects the location of beluga whales, as well as the hunting season 8. Hunting tends to start earlier (end of June) and finish later (early October) because of those changes 1. Monitoring from indicates that the growth rates and thickness of beluga blubber have been declining 5 since The size-at-age declined by 1.75% over the 19-year period. Mercury (Hg) concentrations in beluga whales increased in the 1990s, but decreased between 2002 and This does not, however, correlate with mercury emissions. Instead, this trend relates to distant drivers of climate variability affecting their diet and home range 2. Current mercury concentration levels do not pose a concern for the communities. The decline in beluga growth rates and Hg concentrations may be a result of climate-related ecosystem changes, such as reduced sea ice extent, which can impact Arctic cod - the main prey of beluga whales 7. Research has suggested links between these ecosystem changes and the abundance, nutritional quality and availability of Arctic cod 5, but further research is required to understand those relationships. POLICY LINKAGES: Research under the Hendrickson Island Beluga Program occurs within the Tarium Niryutait Marine Protected Area (MPA) 9. Managed by DFO and FJMC, this MPA was established to conserve and protect beluga whales and other marine species, along with their habitat and ecosystem. Climate change and sea ice loss are affecting the movement of beluga as well as the prey they feed on. That decrease of prey accessibility and potential nutritional quality, given the decrease in thickness of beluga whales, is a concern for food security and, in turn, human health. Data collected from this monitoring initiative are helping to understand the health of belugas and their ecosystem to inform options that can be taken by DFO, together with the FJMC, to ensure the viability of the beluga population and the preservation of hunting for Inuvialuit for cultural and subsistence purposes.

8 - 7 - V 1.6 May 2015 REFERENCES: 1 Harwood, L.A., Kingsley, M.C.S., & Pokiak, F. (2015). Monitoring beluga harvests in the Mackenzie Delta and near Paulatuk, NT, Canada: harvest efficiency and trend, size and sex of landed whales, and reproduction, Can. Manuscr. Rep. Fish. Aquat. Sci. 3059: vi + 32 p. 2 Loseto, L.L., Stern, G.A., & Macdonald, R.W. (2015). Distant drivers or local signals: Where do mercury trends in western Arctic belugas originate? Science of the Total Environment : doi: /j.scitotenv Department of Fisheries and Oceans Canada. (03/20/2015). A health check-up for the beluga whale. Accessed 08 April, Retrieved from: 4 World Wildlife Fund. (December 2012) Getting to know belugas through community-based monitoring. In: The Circle. Ottawa, Canada: WWF Global Arctic Programme. 5 Harwood, L. A., Kingsley, M. C. S., & Smith, T. G. (2014). An emerging pattern of declining growth rates in belugas of the Beaufort Sea: Arctic 67(4): World Health Organization. (September 2013). Mercury and Health. Accessed 14 April Retrieved from: 7 Loseto, L.L., Stern, G.A., Connelly, T.L., Deibel, D., Gemmill B. et al. (2009). Summer diet of beluga whales inferred by fatty acid analysis of the eastern Beaufort Sea food web. Journal of Experimental Marine Biology and Ecology. 374: Hornby, C., Hoover, C., Joynt, A., Torontow, V., Hynes, K. & Loseto, L. (2014). Arrival of Beluga (Delphinapterus leucas) to the Mackenzie Estuary in Relation to Sea Ice: Report on spring aerial surveys. Can. Data Rep. Fish. Aquat. Sci. 1251: vii + 25 p. Accessed 22 April Retrieved from : 9 Beaufort Sea Partnership. (2012). Tarium Niryutait Marine Protected Area. Accessed 14 April Retrieved from: 10 Stroeve, J.C., Serreze, M.C., Holland, M.M, Kay, J.E., Malanik, J., & Barrett, A.P. (2012). The Arctic s rapidly shrinking sea ice cover: a research synthesis. Climatic Change. 110: DOI /s Author: Maeva Gauthier, MSc Marine Ecology

9 - 8 - AERIAL SURVEYS UPDATE NARWHAL MANAGEMENT GUIDELINES FOR EASTERN CANADIAN ARCTIC Summary Narwhal hunting is important for culture and subsistence in many Inuit communities. To sustainably manage narwhal stocks, accurate abundance estimates are required to maintain optimum population levels. Previous surveys conducted between 1975 and 2011 lacked complete coverage of the summering grounds of the Baffin Bay narwhal population in the Eastern Canadian Arctic. The Department of Fisheries and Oceans conducted a High Arctic Cetacean Survey in August 2013 to update population estimates of summering narwhals around Baffin Bay. Corrected abundance estimates for Baffin Bay narwhal total close to 140,000, according to 2013 summer estimates. Individual stocks, which are subpopulation groupings based on distinct summering grounds that surround the Bay, range from 10,000 to 50,000. Survey results can be used to update recommendations regarding sustainable levels of total allowable land catch (TALC) for narwhal summering populations in the Eastern Arctic, and can be used as the scientific basis for decisions regarding the exportation of narwhal products internationally. CONTEXT: In the Canadian Arctic, not only do Inuit communities hunt narwhal for subsistence, but the sale of narwhal ivory in international markets can also be an important source of income for these remote communities 1. From , narwhal catches ranged between annually in the Baffin Bay area 2. Potential biological removal (PBR) level is the maximum number of animals that may be removed from a marine mammal stock while maintaining optimum population numbers. Total allowable land catch (TALC) is calculated as PBR minus estimated hunting losses. In 2004, the narwhal was designated as a species of special concern by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), and is under consideration for inclusion under the Species at Risk Act. To sustainably manage narwhal stocks, accurate abundance estimates are required to prevent population decline. The Department of Fisheries and Oceans (DFO) conducted eleven narwhal surveys in the Eastern Canadian Arctic from 1975 to 2011, but many estimates were incomplete and no survey accounted for all stocks around Baffin Bay in any one summer 3.

10 - 9 - V 1.6 May 2015 In 2013, DFO conducted a High Arctic Cetacean Survey (HACS) in the Eastern Canadian Arctic to update abundance and potential biological removal (PBR) estimates of narwhal stocks and to determine the total allowable land catch levels (TALC) in Nunavut 3. The Nunavut Wildlife Management Board (NWMB) uses these TALC figures for marine mammal management. RESULTS & IMPLICATIONS: Narwhal populations were estimated based on an aerial survey performed in the summer of 2013 in six areas around Baffin Bay, Nunavut: Jones Sound, Smith Sound, Somerset Island, Admiralty Inlet, Eclipse Sound, and East Baffin Island. The total subpopulation of narwhal in each summering ground was considered a distinct stock. Abundance estimates varied from 10,000 to 50,000 narwhal in a given stock. Where comparable to previous surveys from , 2013 estimates are similar or slightly higher. The total Baffin Bay population was close to 140,000, according to 2013 summer estimates. The total allowable land catch (TALC) for each individual stock can be calculated based on the updated abundance estimates with the assumption that narwhal return to the same summering area every year. TALC for summering populations range from 76 for Jones and Smith Sound to 658 for Somerset Island. The total TALC for the Baffin Bay population is 1540 narwhals per year. Future tagging of narwhal will increase knowledge of stock movements. POLICY LINKAGES: The 2013 High Arctic Cetacean Survey is the most extensive survey of the Baffin Bay narwhal population in their summering grounds ever conducted. It provides evidence upon which the Nunavut Wildlife Management Board can update TALC levels for sustainable harvest. Updated narwhal summering population estimates for Baffin Bay can be used by DFO to inform decisions under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) regarding the renewal of export permits required to trade narwhal products internationally. REFERENCES: 1 Convention on International Trade in Endangered Species The Review of Significant Trade in the Narwhal (Monodon monoceros) A briefing by WDCS for the 20th meeting of CITES Animals Committee. AC20 Inf. 9 2 Committee on the Status of Endangered Wildlife in Canada COSEWIC assessment and update status report on the narwhal Monodon monoceros in Canada. Ottawa. vii + 50 pp. 3 Department of Fisheries and Oceans Abundance estimates of Canadian narwhal stocks in the Baffin Bay population in DFO Canadian Science Advisory Secretariat Scientific Advisory Committee. Author: Hilary Dugan, Postdoctoral Researcher, University of Wisconsin-Madison

11 ICE ISLANDS IN THE CANADIAN ARCTIC: IMPLICATIONS FOR SHIPPING AND OFFSHORE OPERATIONS Summary Ice islands are large tabular icebergs that originate from ice shelves and glaciers, including those in Greenland and the Canadian High Arctic. They can drift southward and pose hazards to ships and offshore operations. Researchers from the Water and Ice Research Laboratory (WIRL) at Carleton University and the Laboratory for Cryospheric Research (LCR) at the University of Ottawa have been studying ice islands in the Canadian Arctic since WIRL is also working in partnership with the Canadian Ice Service to create a database of ice islands to analyze their drift and deterioration. Results demonstrate high inter-annual variability of ice island and iceberg formation in the Canadian Arctic. Information from the ice island inventory for the 2010 autumn season has provided insight into ice island deterioration rates and processes, as well as drift patterns. Ongoing monitoring and analysis of ice island calving, drift, deterioration, and associated processes can assist the Canadian Coast Guard and the Canadian Ice Service in advising operators of ships and offshore structures as to where and when they might encounter ice hazards. CONTEXT: Ice islands are large tabular icebergs, which have been observed more frequently in the Canadian Arctic in the past 15 years. Ice islands in the Western Canadian Arctic often originate from ice shelves on Ellesmere Island, and drift southward into the Beaufort Sea 1. In the Eastern Canadian Arctic, they originate from glaciers in northwestern Greenland and drift to the Labrador Sea 2. Ice islands, as well as the Gigatonne (Gt) is a common unit of measurement for ice loss. One gigatonne is one billion tonnes and is equivalent to a block of ice 1km wide by 1km high by 1km thick. smaller icebergs that form as they deteriorate, present serious hazards to ships and offshore operations in these regions. 1 As part of Transport Canada s Northern Transportation Adaptation Initiative, beginning in 2011, researchers at the Water and Ice Research Laboratory (WIRL) at Carleton University and the Laboratory for Cryospheric Research (LCR) at the University of Ottawa studied ice shelf calving and iceberg fluxes from the Canadian Arctic for the period using remote sensing. WIRL has also been working in partnership with the

12 V 1.6 May 2015 Canadian Ice Service since 2014 to develop the Canadian Ice Island Drift and Deterioration Database (CI2D3) to track the drifting of ice islands in the Canadian Arctic and their subsequent deterioration 1. RESULTS & IMPLICATIONS: Results from ice island formation monitoring and the analysis of their drift and deterioration demonstrate the following: In total, 552 km 2 of ice has broken off from the northern coast of Ellesmere Island since 1998 and formed ice islands. These calving events have likely formed the ice islands observed in the Beaufort Sea, as well as in the Northwest Passage. 1 The formation of ice islands from ice shelves on Ellesmere Island occurred at a rate of 1.8 Gt per year on average between 1998 and 2012, but rates were observed at up to 11 Gt per year 1. During three large calving events at the Petermann Glacier in northwest Greenland in 2008, 2010, and 2012, 31 km 2, 253 km 2, and 130 km 2 of ice, respectively, broke away 3,4,, resulting in numerous ice island hazards in the Labrador Sea and Davis Strait 5. Ice islands and ice island fragments present during the period from August to December 2010 have been inventoried in the CI2D3 database. During that period, as the number of ice islands increased, the mean area of the ice islands decreased 6. POLICY LINKAGES: Shipping traffic and offshore operations in the Canadian Arctic have increased in the past decade 7. Ice islands can present serious hazards to vessels in both the Eastern and Western Canadian Arctic 2, 8. The monitoring and analysis work of WIRL and LCR on ice island formation provides baseline information that is needed to monitor changes in the number of ice islands and icebergs in Canadian waters. Additionally, the tracking and analysis of ice island drift and deterioration can assist in documenting changes in ice islands, and better understanding drift patterns, deterioration rates, and processes to assist the Canadian Ice Service and the Canadian Coast Guard in informing operators of ships and offshore structures about where and when they might encounter ice hazards 7. REFERENCES: 1 Mueller, D., Copland, L., Van Wychen, W., Crawford, A. Ice Island and Iceberg Fluxes from Canadian High Arctic Sources. Report prepared for the Innovation Policy Group of Transport Canada, October Peterson IK (2011) Ice island occurrence on the Canadian East Coast. Proc Intl Conf Port and Ocean Eng under Arctic Conditions July in Montréal, Canada. POAC Johannessen, O.M., et al (2011). Petermann Glacier, North Greenland: massive calving in 2010 and the past half century. Cryosphere Discuss. 5: , doi: /tcd

13 NASA. (2012). Earth Observatory: More ice breaks off the Petermann Glacier. Accessed 14 February Available from 5 Falkner, K.K Context for the recent massive Petermann Glacier Calving Event. Eos 92(14): Mueller, D., Crawford, A. (2015). Canadian Ice Island Drift and Deterioration Database (CI2D3), Interim Report; March 31, Department of Geography and Environmental Studies, Carleton University. 7 Pizzolato, L., Howell, S.E.L,, Derksen, C., Dawson, J., Copland, L. (2014). Changing sea ice conditions and marine transportation activity in Canadian Arctic waters between 1990 and Climatic Change. 123: DOI: /s Vanderklippe, N. (December 2, 2012). Marine industries beware: Ice islands dead ahead. The Globe and Mail. Retrieved from: Author: Olivia Mussells MSc. Candidate, University of Ottawa