1. Changes in benthic invertebrate community structure following 16 years of forest succession after logging were examined by estimating benthic invertebrate abundance, biomass and secondary production in streams draining a forested reference and a recovering clear‐cut catchment. Benthic invertebrate abundance was three times higher, and invertebrate biomass and production were two times higher in the disturbed stream. 2. Comparison of invertebrate community abundance 1, 5 and 16 years after clear‐cutting indicated that the proportion of scrapers had decreased, whereas shredders had increased. Functional group percentage similarity indicated that the invertebrate community in the disturbed stream 16 years after clear‐cutting was more similar to the reference than to that found earlier in the disturbed stream. 3. The five indices calculated from data collected over the past 16 years, as well as the abundance, biomass and production data collected during this study, proved to be of differing value in assessing recovery of the disturbed stream from logging. Percent dominant taxon and EPT (Ephemeroptera, Plecoptera and Trichoptera) taxon richness failed to show any initial differences between reference and disturbed streams, indicating that these indices may not be useful for measuring recovery from logging. The percentage Baetis and shredder–scraper indices showed significant differences only during the 1977 study and suggest recovery (no difference between reference and disturbed) by 1982. The North Carolina Biotic Index showed continued differences during 1982 in the riffle and depositional habitats and recovery by 1993. Total macroinvertebrate abundance, biomass and production, as well as EPT abundance, indicated continued differences between the reference and disturbed streams in the 1993 study.

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Amenity migration describes the movement of peoples to rural landscapes and the transition toward tourism and recreation and away from production-oriented land uses (ranching, timber harvesting). The resulting mosaic of land uses and community structures has important consequences for wildlife and their management. This research note examines amenity-driven changes to social-ecological systems in the Greater Yellowstone Ecosystem, specifically in lower elevations that serve as winter habitat for elk. We present a research agenda informed by a preliminary and exploratory mixed-methods investigation: the creation of a "social-impact" index of land use change on elk winter range and a focus group with wildlife management experts. Our findings suggest that elk are encountering an increasingly diverse landscape with respect to land use, while new ownership patterns increase the complexity of social and community dynamics. These factors, in turn, contribute to increasing difficulty meeting wildlife management objectives. To deal with rising complexity across social and ecological landscapes of the Greater Yellowstone Ecosystem, future research will focus on property life cycle dynamics, as well as systems approaches.

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On estime qu'il y a moins que 100 paires des chouettes tachetées du Nord au Canada. Tous ces chouettes tachetées sont dans le sud-ouest de la Colombie-Britannique. En 1986, la chouette tachetée fut classé espèce en danger. Un programme de recouvrement, comprenant six options de gestion, fut développé afin de stabiliser la population des chouettes tachetées et ayant comme but eventuel l'amélioration du statut de l'espèce. Et article a pour objectif de présenter les estimations des coûts d'opportunité des diverses options visant à augmenter la population des chouettes tachetées. Le principal coût d'opportunité est la coupe de bois dans la région peuplée des chouettes tachetées, à laquelle on renonce. Nous rapportons les estimations des coûts d'opportunité au niveau agrégé et au niveau des ménages. Cet article décrit aussi quelques uns des bénefices qui peuvent découler de la protection d'espèces on voie de disparition et discute de quelques problèmes associés à la mesure de ces valeurs.