Article
Ecology
J. Marshall Wolf, Edd Hammill
Summary: Beavers can enhance wetland areas by converting lotic habitats into lentic ponds, and beaver dam analogues (BDAs) are used to restore ecosystems in North America and Europe. This study investigated the impact of beaver dams and BDAs on amphibian breeding occupancy. Barred tiger salamanders were found in natural beaver ponds, while BDAs had lower occupancy rates. Beaver complexes had less fish abundance and were older and deeper than BDAs. The study suggests that future beaver restoration efforts should focus on the top of effective drainages.
FRESHWATER BIOLOGY
(2023)
Article
Ecology
Julianne E. Scamardo, Sarah Marshall, Ellen Wohl
Summary: The decline of beaver populations has led to the failure of beaver dams, resulting in stream incision, water table lowering, and the transition from beaver meadows to drier riparian corridors. A study in Colorado, USA, using the Beaver Restoration Assessment Tool, revealed that the decline in beaver population corresponds to a decline in the capacity to sustain beaver on the landscape, as well as a decrease in physical benefits associated with beaver, such as surface water and sediment storage.
Article
Environmental Sciences
Spencer Dakin Kuiper, Nicholas C. Coops, Piotr Tompalski, Scott G. Hinch, Alyssa Nonis, Joanne C. White, Jeffery Hamilton, Donald J. Davis
Summary: Understanding changes in salmonid populations and their habitat is crucial due to climate change and their importance as a keystone species. Airborne Laser Scanning (ALS) data can be used to assess the quality and quantity of salmonid habitat, as well as characterize detailed stream attributes. ALS data provides detailed Digital Elevation Models (DEMs) and can be utilized for sustainable forest management decision making and advanced salmonid habitat modeling.
REMOTE SENSING OF ENVIRONMENT
(2022)
Article
Environmental Sciences
Tariq M. Munir, Cherie J. Westbrook
Summary: This study investigated the impact of three types of BDA configurations on stream hydrology and the riparian water table in the Canadian Rocky Mountains. Results showed that all configurations significantly elevated upstream stage, with different effects on flow peaks and low flows. Additionally, a significant rise in riparian water table was observed after the installation of BDAs, with the highest water table rise occurring 2 meters from the stream and diminishing with increasing lateral distance.
RIVER RESEARCH AND APPLICATIONS
(2021)
Article
Ecology
A. A. D. McLaren, E. J. Newton, A. Silver, M. R. Allan, K. R. Middel, B. A. Pond, B. R. Patterson
Summary: A systematic aerial photographic census was conducted to quantify the annual beaver colony abundance on Michipicoten Island, Ontario. It was found that the beaver colony abundance declined from its peak in 2015 to a much lower level in 2018.
Article
Ecology
Anna Treves, Andrea Terenziani, Christof Angst, Elena Comino
Summary: This paper proposes the use of Ecological Niche Models to explore the potential for reintroducing Eurasian beavers in Italy. The results show potential habitats along main watercourses in foothill and plain zones. The study suggests that this model can be a useful tool in selecting appropriate reintroduction sites.
ECOLOGICAL INFORMATICS
(2022)
Article
Ecology
Anthonie M. A. Holthuijzen
Summary: This study observed 11 years of passive restoration of a small mountain stream in northeastern Oregon, which resulted in strong recovery of riparian vegetation in the middle two-thirds of the reach and a decline in stream temperature. American beavers played a crucial role in improving streambed conditions, while passive restoration was not effective in some sections.
Review
Biodiversity Conservation
Bartosz P. Grudzinski, Ken Fritz, Heather E. Golden, Tammy A. Newcomer-Johnson, Jason A. Rech, Jonathan Levy, Justin Fain, Jessica L. McCarty, Brent Johnson, Teng Keng Vang, Karsten Maurer
Summary: Beavers are reclaiming their old habitats, expanding into new territories, and being protected for stream conservation in various environments. The effects of beaver dams on streams are complex and vary among different biomes. Most studies have been conducted in temperate forests, leaving many biomes understudied. Beaver dams prefer sites with low slopes, unconfined reaches, and small drainage areas. The impact of beaver dams on stream morphology and hydrology is relatively consistent across biomes, while water quality and biotic responses vary. Further research is needed in arid and cold biomes historically occupied by beavers and in new biomes where beaver populations are growing.
GLOBAL ECOLOGY AND CONSERVATION
(2022)
Article
Ecology
John R. Stevenson, Jason B. Dunham, Steven M. Wondzell, Jimmy Taylor
Summary: The study found that water temperatures increased for short distances below monitored beaver ponds and observed oxygen conditions within ponds were largely unsuitable for salmonid fishes. Managers should consider these expectations prior to implementation, especially in streams where temperature or DO restoration are objectives.
Article
Fisheries
Dylan S. Cunningham, Douglas C. Braun, Jonathan W. Moore, Amanda M. Martens
Summary: Human activities such as forestry can have negative impacts on freshwater ecosystems that support juvenile salmon. Forestry activities alter water temperatures and the delivery of water and nutrients in streams, affecting the habitat and survival of juvenile salmon. This study examines the relationship between forestry and stream habitat in interior watersheds and finds that forest harvest is positively correlated with maximum summer stream temperature, while stream gradient explains most of the variation in physical habitat.
CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES
(2023)
Article
Biodiversity Conservation
Philip R. Kaufmann, Robert M. Hughes, Steven G. Paulsen, David V. Peck, Curt W. Seeliger, Marc H. Weber, Richard M. Mitchell
Summary: Quantitative measures of physical habitat structure are important indicators of the impacts of human activities on stream and river condition.
ECOLOGICAL INDICATORS
(2022)
Article
Multidisciplinary Sciences
Christian Andre Robstad, Hanna Kavli Lodberg-Holm, Martin Mayer, Frank Rosell
Summary: The study found that tagging Eurasian beavers can lead to a reduction in daily body weight but the specific mechanisms behind this effect are unclear. Tag weight, number of tagging days, and season did not have a significant impact on the body weight change of tagged animals. The detrimental effects of tagging have implications for animal welfare and data bias, emphasizing the importance of careful consideration in tag use.
Article
Ecology
Valerio Orazi, Jonas Hagge, Martin M. Gossner, Joerg Mueller, Marco Heurich
Summary: Beavers, as ecological engineers, increase habitat heterogeneity in mountain forests and promote biodiversity conservation and restoration.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2022)
Article
Marine & Freshwater Biology
Jared R. Ellenor, Peter A. Cott, Heidi K. Swanson
Summary: The study addressed knowledge gaps on suitable stream attributes for rearing young-of-year Arctic grayling, finding that lake area and land classification data are key predictors of occupancy. Results suggest that occupancy reflects the reliability of stream connectivity, providing guidance for conservation and mitigation plans.
Article
Ecology
Clinton W. Epps, Vanessa M. Petro, Tyler G. Creech, Rachel S. Crowhurst, Matthew J. Weldy, Jimmy D. Taylor
Summary: Genetic studies on American beavers in western Oregon showed that gene flow among beaver populations is influenced more by landscape features such as watershed boundaries rather than geographic distance. In this topographically complex system, genetic differentiation of beavers was much greater than in studies at similar spatial scales in flatter terrain.
JOURNAL OF WILDLIFE MANAGEMENT
(2021)