Biased representation of disturbance rates in the roadside sampling frame in boreal forests: implications for monitoring design
Document Type: Journal Article
Author(s): S. L. Van Wilgenburg; E. M. Beck; B. Obermayer; T. Joyce; B. Weddle
Publication Year: 2015

Cataloging Information

  • BBS
  • bias
  • boreal forest
  • boreal forests
  • Canada
  • disturbance
  • disturbance
  • fire management
  • forest fire
  • North American Breeding Bird Survey
  • population density
  • Roadside Sampling
  • wildfires
  • wildlife management
Record Maintained By:
Record Last Modified: June 1, 2018
FRAMES Record Number: 54491
Tall Timbers Record Number: 32218
TTRS Location Status: Not in file
TTRS Call Number: Available
TTRS Abstract Status: Okay, Fair use, Reproduced by permission

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.


The North American Breeding Bird Survey (BBS) is the principal source of data to inform researchers about the status of and trend for boreal forest birds. Unfortunately, little BBS coverage is available in the boreal forest, where increasing concern over the status of species breeding there has increased interest in northward expansion of the BBS. However, high disturbance rates in the boreal forest may complicate roadside monitoring. If the roadside sampling frame does not capture variation in disturbance rates because of either road placement or the use of roads for resource extraction, biased trend estimates might result. In this study, we examined roadside bias in the proportional representation of habitat disturbance via spatial data on forest 'loss,' forest fires, and anthropogenic disturbance. In each of 455 BBS routes, the area disturbed within multiple buffers away from the road was calculated and compared against the area disturbed in degree blocks and BBS strata. We found a nonlinear relationship between bias and distance from the road, suggesting forest loss and forest fires were underrepresented below 75 and 100 m, respectively. In contrast, anthropogenic disturbance was overrepresented at distances below 500 m and underrepresented thereafter. After accounting for distance from road, BBS routes were reasonably representative of the degree blocks they were within, with only a few strata showing biased representation. In general, anthropogenic disturbance is overrepresented in southern strata, and forest fires are underrepresented in almost all strata. Similar biases exist when comparing the entire road network and the subset sampled by BBS routes against the amount of disturbance within BBS strata; however, the magnitude of biases differed. Based on our results, we recommend that spatial stratification and rotating panel designs be used to spread limited BBS and off-road sampling effort in an unbiased fashion and that new BBS routes be established where sufficient road coverage exists. Copyright © 2015 by the author(s). Published here under licenses by the Resilience Alliance.

Online Link(s):
Van Wilgenburg, S. L., E. M. Beck, B. Obermayer, T. Joyce, and B. Weddle. 2015. Biased representation of disturbance rates in the roadside sampling frame in boreal forests: implications for monitoring design. Avian Conservation and Ecology, v. 10, no. 2, p. 5. 10.5751/ACE-00777-100205.