Restoration for Improved Resilience, Biodiversity and Status in Boreal Rivers

PROJECT DESCRIPTION

BACKGROUND

Large rivers in the southern part of the boreal region are in general heavily affected by human activities.

Large-scale timber floating has led to narrow and channelised water courses, blocked side channels, removed in-stream boulders and dead wood. As the natural heterogeneity of the rivers decreased, water velocity increased, and gravel as well as finer fractions were flushed out of the riffles. Consequently, habitat heterogeneity and biodiversity of algae, invertebrates and fish have diminished as well asaquatic productivity.

Commercial forestry involves practices detrimental to rivers. Increased siltation from scouring vehicle tracks, ditching and other forestry activities as well as clear-cutting of riparian forest have the most profound effects. In addition, dead trees, important habitat structures in the water and in the riparian zone, are scarce due to logging.

Old dams and misplaced road culverts reduce the possibility for fish, otter and other organisms to move freely in the water system.

OBJECTIVES

Parts of three river systems in east-central Sweden with unique character and high natural values are included in the Rivers of LIFE project. All of them are negatively impacted by anthropogenic activities (mainly stream clearance for timber floating) but have a potential for considerable habitat enhancement.

The project has a holistic (catchment) perspective and three main objectives: 1. To improve the conservation and ecological status of selected riverine habitats and aquatic species of Community interest, by restoring habitat quality, stream connectivity and hydrology; 2. To enhance ecosystem structure and function of large boreal rivers to improve resilience to climate change, as well-functioning, diverse ecosystems are expected to better withstand changes caused by climate change; and 3. To interconnect conservation action with sustainable development of local economies. The project areas are in a sparsely populated region with few opportunities for business.

Conservation actions will improve riverine habitats and enhance natural fish populations, which in turn will establish prerequisites for the development of sustainable sport fishing tourism.

RESULTS

Expected results: Significantly improved conservation status by:

restoration of around 120 km/370 ha of river sections and remediation of historic timber floating impact;

re-creation of approx. 320 spawning grounds for brown trout(Salmo trutta), which will increase habitat suitable also for grayling (Thymallus thymallus) and young pearl mussel (Margaritifera margaritifera);

re-introduction of dead wood into the riparian zone at 34 locations, for example, creating habitats for liverwort (Scapania spp.); and

remediation of hydromorphological and/or connectivity impact in >30 waterbodies, which will, after the natural recovery period, lead to Good Status for the respective quality factor or to Good Ecological Status for the water body in accordance with EU Water Framework Directive

increased heterogeneity of the river channel geometry by reintroducing rocks and boulders, into the stream, leading to: - increased total wetted area (estimated 5-10% of restored habitat), as water can expand the natural riverbed; - decreased water velocity in formerly channelised sections and downstream restored sites; - increased access of aquatic fauna to the entire floodplain at high flows; and - organic matter such as leaves, transported by the current and important for the growth and density of aquatic invertebrates, will remain in the restored sections to a larger extent.

connectivity barriers at 14 dams and 28 road culverts remediated;

increase of brown trout populations because of the restoration of spawning grounds, habitat restoration and fish barrier removal;

increased population size and distribution of freshwater pearl mussel, because of the restored habitat (ca. 180 ha new potential habitat), reintroduction and the increased stocks of brown trout. Estimated annual recruitment to reintroduced populations is 17 000 mussels;

increased population of otter because of the increased stocks of stream-dwelling fish (10-20%);

capania carinthiaca and other rare Scapania species returned to the restored dead wood habitats in the riparian zones (17 new populations);

increased ecosystem resilience in a climate change perspective due to enhanced structure and function of ecosystems;

increased numbers of visiting anglers (>5% more licenses sold) because of the improved stocks and sustainable use of stream fish (grayling and brown trout). Consequently, local economy will be enhanced;

detailed, adaptive management plans, enhancing sustainability of the fishery for stream fish populations, developed and implemented after information and education of stakeholders;

enhanced public awareness of aquatic conservation needs due to an extended public campaign, pushing for conservation of water nature, with focus on recently arrived immigrants and schools; and

at least 400 persons/landowners involved in forestry practises informed of best practice forestry methods for the protection of aquatic habitats.