Study
Alteration of North American streams by beaver
Naiman, Robert J.; Johnston, Carol A.; Kelley, James C.
BioScience, 1988
Surveys the physical and chemical consequences of beaver damming across stream catchments: water storage, sediment retention, channel form, flow regime, nutrient processing and the extent of standing water and wetland relative to undammed reaches.
- Studied in
- Castor canadensis
- Sample size
- catchment-scale survey of dammed and undammed reaches
Damming raises water tables, retains sediment and organic matter, converts running water to standing water over substantial areas, alters nutrient cycling, and increases the variety of habitat types present in a catchment.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Beavers restructure stream systems at catchment scale, and their historical removal represents a large and under-recognised alteration of North American landscapes.
How NatureHQ reads it
The scale is the part worth carrying. This is not one pond: before trapping, beavers occupied streams across most of a continent, and the removal converted enormous areas of wetland into channel. Reading this alongside the Yellowstone willow experiment explains something the wolf story omits — the missing water tables there are the local remnant of a continental change that happened a century earlier.
- Largely observational comparison of dammed and undammed reaches, which differ for reasons other than beavers.
- North American systems; effects elsewhere depend on hydrology and vegetation that differ.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: University press journalsPublished in a university press journal.
Checked against Crossref on 2026-09-28, and they agree on the title, the authors and the year.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-09-04.