Long-term responses of ecosystem components to stand thinning in young lodgepole pine forest. I. Population dynamics of northern flying squirrels and red squirrels

  • Published source details Ransome D.B., Lindgren P.M.F., Sullivan D.S. & Sullivan T.P. (2004) Long-term responses of ecosystem components to stand thinning in young lodgepole pine forest. I. Population dynamics of northern flying squirrels and red squirrels. Forest Ecology and Management, 202, 355-367.


This study is summarised as evidence for the following.

Action Category

Thin trees within forest

Action Link
Terrestrial Mammal Conservation
  1. Thin trees within forest

    A replicated, controlled study in 2000–2002 of three coniferous forest sites in British Columbia, Canada (Ransome et al. 2004) found thinning of lodgepole pine Pinus contorta stands resulted in higher numbers of northern flying squirrels Glaucomys sabrinus when resultant tree density was high, whilst thinning did not affect abundances of red squirrels Tamiasciurus hudsonicus. Average northern flying squirrel abundance was highest in thinned stands where remaining trees were at high density (4.6 squirrels/stand), intermediate in medium density stands (3.3/stand) and lowest in low density (1.3/stand) and unthinned (1.8/stand) stands. Red squirrel abundance did not differ between treatments (high density: 10.8/stand; medium density: 9.7/stand; low density: 13.5/stand; unthinned: 11.3/stand). In each of three sites, four forest stands, regenerating following felling and/or wildfire in 1960–1972, were studied. In 1988–1989, one stand each in each site was thinned to approximately 500 (low), 1,000 (medium), and 2,000 (high) stems/ha and one was unthinned (with 4,700–6,000 stems/ha in 1988). Squirrels were surveyed using Tomahawk live traps, at 4-week intervals, from May–October 2000 and 2001 and at 8-week intervals in 2002. One trapping grid (9 ha, 50 traps) was located in each stand.

    (Summarised by: Nick Littlewood)

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 20

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.

Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape Programme Red List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Bern wood Supporting Conservation Leaders National Biodiversity Network Sustainability Dashboard Frog Life The international journey of Conservation - Oryx British trust for ornithology Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered speciesVincet Wildlife Trust