AS10: From individual stressors to cumulative impacts: Improving knowledge in the Arctic marine environment

Date: Friday October 12, 2018

Location: Kero, Lappia Hall

Time: 8:30-10:00

According to CAFF’s recent State of the Arctic Marine Biodiversity Report (SAMBR), Arctic marine species and ecosystems are undergoing pressure from cumulative changes in their physical, chemical and biological environment. Some changes may be gradual, but there may also be large and sudden shifts that can affect how the ecosystem functions. It is hard to determine where and when these “tipping points” exist because the Arctic marine environment experiences a variety of stressors and subsequent reactions that can interact in complex and surprising ways. For those charged with managing natural resources and public policy in the region, it is crucial to identify the combined effects of stressors and potential thresholds to prepare effectively for an uncertain future. This session will contain presentations on various stressors in the Arctic marine environment, touching on themes of pollution, invasive species, industrial development, microplastics and climate change. The following discussion will explore how to conceptualize change in the Arctic marine environment in the face of cumulative impacts.

Chair: Catherine Coon, Bureau of Ocean Energy Management

Format: Series of presentations followed by discussion

Presentations:

1. ARCTOX: a pan-Arctic sampling network to track the mercury contamination of Arctic seabirds and marine food webs: Jerome Fort, French National Center for Scientific Research (LIENSs-CNRS) 
2. The reefs of the Arctic - photoautotrophic ecosystem engineers endangered by microplastic and climate change? Sebastian Teichert, GeoZentrum Nordbayern, Friedrich-Alexander-Universität Erlangen-Nürnberg
3. Invasive Crab Species in the Barents Sea: Stakeholder Perceptions, Incentives, and Path Dependencies: Brooks Kaiser, University of Southern Denmark 
4. Environmental impacts of drill cuttings deposition on sea floor biodiversity in the south-western Barents Sea – a contribution to ecosystem-based management: Sabine Cochrane, Akvaplan-niva 
5. Building an ecological atlas: from spatial data to conservation across dynamic Arctic seas: Benjamin Sullender, Audubon Alaska 

Abstracts:

ARCTOX: a pan-Arctic sampling network to track the mercury contamination of Arctic seabirds and marine food webs

Jerome Fort, French National Center for Scientific Research (LIENSs-CNRS)

The Arctic wildlife is exposed to increasing levels of pollutants in their environment under the combined effects of climate change and human activities. Among them, mercury has raised important environmental concerns. In its methylated form, mercury is indeed highly toxic and has adverse effects on organisms, even at very low concentrations, including endocrine, neurotoxic or reproductive effects. Mercury could therefore have important impacts on Arctic organisms, biodiversity and ecosystems as a whole. In that context, monitoring mercury concentrations in Arctic wildlife at very large spatial scale is essential (1) to assess exposure and associated risks for different populations and species, (2) to define hotspots of mercury contamination and highlighting sensitive areas that require particular attention and protection and (3) to better apprehend impacts of anthropogenic activities and climate change on the exposure of Arctic species to mercury. In 2015, an international network (ARCTOX) has been established, allowing the coordinated collection of seabird samples all around the Arctic to investigate the pan-Arctic mercury contamination of seabirds and marine food webs. Seabirds are indeed important organisms to study as they are particularly vulnerable to environmental stressors including Hg, but also because they are good indicators of the environmental contamination. Gathering researchers from 12 countries, ARCTOX thus allowed the collection of >7000 samples from 20 seabird species and at 56 Arctic sites between 2015 and 2017. By relying on this network and unique data set, we monitored and mapped the exposure of the Arctic seabird community to mercury at the pan-Arctic scale. Importantly, by analyzing different tissues (blood and feathers), we investigated the contamination of these migratory organisms during different periods of their annual cycle: both their Arctic breeding season and the non-breeding period often spent far from the Arctic. Furthermore, measured concentrations were compared to toxicity thresholds to highlight species and regions where mercury might have major impacts. Finally, we used seabirds as bioindicators to further understand the large-scale contamination of Arctic marine food webs. Obtained results are therefore essential to complement existing monitoring programs (i.e. Arctic Monitoring Assessment Programme, UN-Environment Global Mercury Assessment) and for the conservation of the Arctic biodiversity.

The reefs of the Arctic - photoautotrophic ecosystem engineers endangered by microplastic and climate change?       

Sebastian Teichert, GeoZentrum Nordbayern, Friedrich-Alexander-Universität Erlangen-Nürnberg; Martin Löder, Department of Biology, Universität Bayreuth; Christian Laforsch, Department of Biology, Universität Bayreuth; Ines Pyko,  GeoZentrum Nordbayern, Friedrich-Alexander-Universität Erlangen-Nürnberg; Christian Schulbert, GeoZentrum Nordbayern, Friedrich-Alexander-Universität Erlangen-Nürnberg; Max Wisshak, Marine Research Department, Senckenberg am Meer

Large areas of the Svalbard shelf are covered by rhodoliths, coralline red algal structures which form a rigid framework of magnesium calcite. They act as ecosystem engineers, comparable to corals in tropical regions. Additionally, many rhodoliths are gouged by boring mussels and become hollow ecospheres which are intensely colonised by benthic organisms. The existence of both, solid and hollow rhodoliths has a significant impact on local biodiversity. However, this special ecosystem is threatened by the contamination with microplastic. We detected eight different types of microplastic within the bodies of the boring mussels, whereof polystyrene is the most common. If the particles are harmful to the mussels, their future role as niche providers is endangered and the consistency of the whole community is doubtful. Furthermore, we could show that the rhodoliths themselves are endangered by climate change in terms of increased glacial runoff, as coverage with sediments and reduced transparency of the water column are significantly impairing the growth conditions of the rhodoliths. This twofold environmental deterioration will have unpredictable consequences for the associated organisms. This special but extensive ecosystem plays a crucial role on Svalbard’s shelf biodiversity and should be included in future policy recommendations and strategic plans for biodiversity.

Invasive crab species in the Barents Sea: Stakeholder perceptions, incentives, and path dependencies  

Brooks Kaiser, University of Southern Denmark; Melina Kourantidou, University of Southern Denmark

The red king and snow crab invasions in the Barents Sea are harbingers of how economics, ecology, politics, law and institutions will all affect how communities and ecosystems adapt as climate change and human behavior lead to greater numbers of invasive species introductions, and resulting changes in ecosystem composition and productivity. As profitable invaders, incentives for their management are mixed. Questions of whether and how to treat the newcomers abound. Should they be treated as species in need of eradication to prevent ecosystem changes and protect other commercial and non-commercial ecosystem assets that may be affected by their entry into new ecosystems? Or should they be treated as species to protect and conserve -- desirable food commodities whose home range habitats in other parts of the Arctic are experiencing climate variabilities that make their continued production in those locations uncertain? What are the benefits and costs of these potential paths? How do the answers vary spatially? Upon what current uncertainties do decisions rest, and what incentives, ranging from funding to stakeholder interests in the questions asked, affect when and how these uncertainties can be resolved? We parse the complexities by identifying local, regional, and global incentives pertaining to current ecosystem conditions as well as future conditions that will evolve through management decisions for invasive species at every stage, from research and prevention to accommodation and adaptation. We use the crab cases to illustrate the multidimensional human and ecosystem pressures at work in transforming from current to expected future outcomes, and how interventions into the human and/or ecological systems can be expected to reverberate through one another. 

Environmental impacts of drill cuttings deposition on sea floor biodiversity in the south-western Barents Sea – a contribution to ecosystem-based management

Sabine Cochrane, Akvaplan-niva

As the petroleum industry is increasingly moving into Arctic waters, awareness of environmental issues is critical to sustainable operations. In accordance with world-wide conventions, petroleum operators in the Norwegian sector adhere to guidelines and requirements for monitoring and protection of marine biodiversity in the Arctic. Drilling at the sea-floor generates quantities of drill cuttings, which are a mixture of sediment and rock particles and any compounds used during the drilling process. In most cases, at least some of the drill cuttings are discharged at the sea floor, generally forming a circular area of deposited matter around the drilling location. We have investigated the impacts of such deposition on sea floor biodiversity in the south-western Barents Sea, both in time and space. The study area is around 350 m in depth and mostly comprises silty-muddy bottom sediments. Most of the macro-biodiversity is buried within the sea floor, but scattered sponges and other organisms can be seen at the surface. We visited seven drilling locations between 2014-2015, of which the "youngest" well was drilled in 2015 and the oldest in 1987. Using the same standardised methodology as for routine environmental surveys, we sampled and analysed macrofaunal community structure at distances 30 m, 60 m, 125 m and 250 m from the drilling locations. We also conducted visual assessments of the drill cuttings deposition. Our initial hypothesis was that deposition of drill cuttings will result in local smothering/destruction of the biota closest to the drilling location, and that the affected areas would recover over time. Our study showed minor reductions in abundances of a few taxa, notably sessile tube-dwellers, but only at the innermost locations at the freshest drilling sites. The majority of the species did not show any significant changes within the communities. At wells sampled 3-5 years post-drilling and older, we found no trends in the communities which could be related to drilling impacts. One possible explanation is that the sea floor in these areas is flocculent and frequently resuspended by natural events such that the resident fauna, mostly free-living organisms which move and reproduce rapidly, is resilient to physical disturbance. This knowledge is presented as a contribution to decision-making on offshore waste management strategies, which aim to promote overall best environmental practices. Our results are relevant to the CAFF Actions for Arctic Biodiversity, particularly ecosystem-based management (Recommendation 3), addressing stressors on biodiversity (Recommendation 11) and ongoing communication and outreach (17). 

Building an ecological atlas: from spatial data to conservation across dynamic Arctic seas     

Melanie Smith, Audubon Alaska; Max Goldman, Audubon Alaska; Erika Knight, Audubon Alaska; Benjamin Sullender, Audubon Alaska; Brianne Mecum, Oceana; Jon Warrenchuk, Oceana; Molly Zaleski, Oceana

To inform sustainable management in a time of growing human influence, there is a need to synthesize and disseminate scientific information to policy makers, scientists, and the public in a format that is useful and accessible. The goal of the Ecological Atlas of the Bering, Chukchi, and Beaufort Seas was to create a comprehensive, trans-boundary atlas that represents the current state of knowledge on subjects ranging from physical oceanography to species ecology to human uses. Layer by layer, the Ecological Atlas provides a cumulative representation of what is happening in the region to better understand ecological patterns through spatial data, maps, and written summaries. The Atlas is organized into six topic areas that build, layer by layer, the ecological foundation of these three seas: physical setting, biological setting, fish, birds, mammals, and human uses. The atlas was a project by Audubon Alaska, in collaboration with Oceana and somethingaboutmaps. Numerous agencies and organizations assisted by providing spatial data, expertise, and review, including the Bureau of Ocean Energy Management, Kawerak, National Oceanic and Atmospheric Administration, US Fish and Wildlife Service, and US Geological Service. Our data-to-design process involved intensive research and consultation with experts, as well as gathering and analyzing the most recent or otherwise best available data from scientific and traditional knowledge sources. We synthesized data to create more than 100 seamless maps that integrate disparate datasets into cohesive data layers that visually describe a particular process or species’ habitat use across the three seas. The Ecological Atlas is a data-rich foundation for understanding the complex dynamics of the Arctic marine ecosystem, which can be applied toward managing an array of contemporary human uses. Subsequent analyses build on this foundation by identifying important ecological areas and assessing vulnerability to offshore energy, vessel traffic, commercial fisheries, and climate change. The Ecological Atlas addresses Arctic Biodiversity Congress goals and Assessment actions by identifying important areas, addressing stressors, promoting sustainable development, and improving knowledge and public awareness.