Hidden forests in Arctic oceans

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    Large sugar kelp (Saccharina spp) makes diving in Arctic kelp forests feel like walking through a terrestrial forest. © I. Garrido

     The next economic opportunity?

    Luxuriant Arctic forests 

    In cold marine waters, rocky reefs are often dominated by habitat-forming seaweeds such as kelp. These seaweeds form impressive underwater forests that are not only a phenomenal source of primary productivity and food, but also create three- dimensional structure that provides valuable habitat for many animals and other seaweeds, including harvested species. The recipe for kelp forests in many regions of the world is deceptively simple: a rocky seafloor, enough light to support growth, cool nutrient-rich waters, and low grazing pressure to ensure survival. Add protection from ice scour to this mix and you have the formula for predicting the potential distribution of kelp in Arctic regions. 

    Large stretches of coastline are likely rocky enough to support kelp forests, and the potential distribution of kelp in the Canadian Arctic is astoundingly large (thousands of kilometres of rocky coastline). However, there is little published information on the spatial distribution and types of seaweed that make up Arctic kelp forests. Moreover, environmental conditions along these coastlines are changing rapidly. For example, increased light availability caused by sea ice retreat is predicted to expand the northern extent and overall productivity of kelp in the Arctic. 

    Trying on dive gear in Pond Inlet with Ladd Johnson. © K. MacGregor

    ArcticKelp is a three- to five-year ArcticNet Research Project that aims to answer three main questions about Arctic kelp forests: 1) Where are they and what types are most abundant in different regions? 2) What effects will climate change have on their distribution and productivity? And 3) What is their value to northern communities? 

    Large-scale surveys 

    Although sea ice and shortened day-length in winter reduce annual light in Arctic waters, light levels are clearly high enough in many areas to support kelp growth. Since the first step in the ArticKelp project aims to carry out a large-scale survey of the presence and types of kelp forests across the eastern Canadian Arctic, teams of researchers and local collaborators have begun to collect information about kelp forests in shallow (five to 15 m deep) coastal areas which should have enough light to support macroalgae (Iqaluit, Nunavut, and Churchill, Manitoba, in 2011; Steensby Inlet, Nunavut, and Deception Bay, Quebec, in 2012; the eastern coast of Baffin Island, Nunavut, in 2014; Anaktalak Bay, Newfoundland in 2018; Southampton Island, Nunavut, in both 2018 and 2019; and in Eclipse Sound and Milne Inlet, Nunavut, in 2017 and 2019). Using a combination of SCUBA diving and dropped or towed cameras, research teams (including local Inuit, universities and government) have surveyed more than 50 sites. 

    Diver sampling an urchin barren from Labrador. © K. MacGregor

    This effort represents an enormous leap forward in mapping the spatial extent of kelp forests in the Arctic and in documenting which types of kelp are found where. Surprisingly, kelp forests were found at almost all sites, and covered large areas of the seafloor. Overall, sugar kelp, Saccharina spp. (a group of kelp widely distributed in both temperate and polar latitudes), dominated in what appeared to be particularly productive areas such as sites in the northern portion of Labrador and around Southampton Island. Contrary to expectations, the endemic Arctic kelp, Laminaria solidungula, was never the dominant species in the regions surveyed. We are particularly interested in exploring what environmental factors are most important in determining the distribution and composition of the kelp communities observed and predicting what kelps may be present in areas that we have yet to visit! 

    A key study area for this project is in the waters of Eclipse Sound near the community of Mittimatalik (Pond Inlet) where intensive exploration, including dive surveys, was carried out in 2019. Work elsewhere in the Arctic and previously published work in this area led us to believe that kelp assemblages would be composed of a mix of types (species), dominated by Alaria esculenta in shallower waters and by Saccharina spp. and Laminaria solidungula at greater depths with a patchy distribution of Agarum clathratum in the deepest waters or in more marginal habitats. Instead, we found an overwhelming dominance by Agarum at almost all sites and all depths. This may indicate that Eclipse Sound is a more extreme habitat for kelp than we had expected based on previous research. 

    Future work will try to determine what factors are limiting the abundance and distribution of other kelp species by examining the effects of light, ice, grazing and kelp recruitment. These Agarum beds were, however, clearly functioning as important habitat for a large number of animals, with fish (Arctic cod and sculpins — known as ‘ugly fish’) and numerous invertebrate species (e.g., urchins, sea stars, brittle stars, shrimp and anemones) strikingly abundant. 

    Kelp forests and northern communities 

    A central goal of the project is to provide opportunities for training and knowledge transfer, while also exploring possible economic opportunities that kelp forests could present for northern communities and local Inuit businesses. Kelp forests are clearly beneficial in that they provide habitat for fished or harvested species and their prey In 2019, the ArcticKelp team ran an informal interpretative touch tank filled with organisms collected during each day of diving work and carried out school visits at (for example, fish and shrimp). Some kelp species are also valuable as direct consumables. Indeed, the kuane (Alaria esculenta) collected during sampling was consumed as a treat in Mittimatalik. Some algal species are also being increasingly used as ingredients in traditional or traditionally inspired products (for example, Bowhead whale cosmetics with algal ingredients — UasaU Soap of Iqaluit, Nunavut). Future possibilities for economic development based on local kelp forests remain to be fully explored with communities but could include extraction of biomolecules as food additives, use of tannins such as those found in Agarum, or production of algal extracts for use in other products. 

    In 2019, the ArcticKelp team ran an informal interpretative touch tank filled with organisms collected during each day of diving work and carried out school visits at the end of fieldwork to share information about kelp forests and associated marine life with children at elementary and high schools in Mittimatalik. 

    Touch tank gang in Pond Inlet with Karen Filbee-Dexter. © L. Johnson

    The ArcticKelp team was assisted by two invaluable local Inuit research technicians, Trevor Arreak and Cara Killiktee, who had previous training from the Environmental Technology Program at the Nunavut Arctic College. 

    Although sampling in 2020 was cancelled due to COVID-19, ArcticKelp is planning further fieldwork and community outreach, and will define future research goals based on local priorities and interest. 

    Climate change is having particularly dramatic effects in the Arctic, with reduced sea ice thickness and cover being the most marked and worrying trend. Surface temperatures in parts of the Arctic are also rising more than four times faster than in the oceans to the South. Although these changes clearly have negative effects on many species and coastal processes, including impacting the food security and access to traditional resources of Inuit in northern communities, future conditions may, in fact, benefit certain species. Indeed, kelp forests are predicted to expand their range northwards as waters warm and annual light increases in coastal zones due to reduced ice cover. However, because so little is currently known about the distribution of Arctic kelp species and the factors limiting their distribution and productivity, predicting future changes with certainty is difficult. Given the ecological and cultural importance as well as the economic potential of kelp forest habitats, the research being carried out by the ArcticKelp project will provide critical information for Arctic decision makers, leaders and entrepreneurs. 

    Acknowledgements 

    A version of this article was previously published in the Coastal Zone Canada Newsletter (Winter 2020 edition). 

    The ArcticKelp project would be impossible without the collaboration and help of many people, both during the planning and execution of this work. The collaboration and support of the following organizations has made ArcticKelp possible: the Nunavut Fisheries Association; the Nunavik Marine Region Wildlife Board; the Mittimatalik Hunters and Trappers Organization; the Department of Wildlife and Environment, Nunavut Tunngavik Inc.; Oceans North; the Circumpolar Biodiversity Monitoring Program (CBMP); Natural Resources Canada; Fisheries and Oceans Canada, including the DFO Strategic Program for Ecosystem-Based Research and Advice and the DFO Aquatic Invasive Species Monitoring Program; the Institute of Marine Research, Norway; the Polar Continental Shelf Program; Sentinel North; Memorial University of Newfoundland; Université Laval; Québec-Océan; Glencore (Raglan Mine); Vale (Voisey’s Bay Mine); and Baffinland (Mary River Mine). 

    Diving in Arctic kelp forests requires help at the surface! © I. Garrido

    For invaluable help in the field, we thank the crew of the MV Cape Race (2014); the crew of the MV William Kennedy (2018 and 2019); the crew of the MV Nuliajuk (2017 and 2019); the collaborative SIMEP research team led by CJ Mundy; our assistants in Mittimatalik and Eclipse Sound, Trevor Arreak, Cara Killiktee, Andrew Arreak, Tapisa Kasarnak and Markusi Jaaka; Leo and Myna Maktar for use of an amazing boat and discussions about observations of seaweed; the Mittimatalik HTO and particularly Joseph Arreak and Andrew Arreak for invaluable help organizing diving field work; the ECCC field station for providing an amazing base for working in Eclipse Sound; and ArcticNet for providing financial support and Amundsen Science for logistical support (particularly Cindy Grant and Lisa Treau De Coeli) to make this work possible. 

    www.ArcticKelp.ca 

    Submitted by Kathleen MacGregor, Karen Filbee-Dexter, Ladd Johnson, Chris McKindsey, Kimberly Howland, Jesica Goldsmit, Robert Schlegel, Camille Lavoie, Ignacio Garrido, and Philippe Archambault. 

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