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Mountain caribou, a behaviourally and genetically distinct set of ecotypes of the Woodland caribou (Rangifer tarandus caribou) restricted to the mountains of western Canada, have undergone severe population declines in recent decades. Although a broad consensus exists that the ultimate driver of these declines has been the reduction of habitat upon which mountain caribou depend, research and policy attention has increasingly focused on predation. Recently, Serrouya et al. (Proc Nat Acad Sci USA 116:6181–6186, 2019) analysed population dynamics data from 18 subpopulations in British Columbia and Alberta, Canada, subject to different treatments and ‘controls’, and concluded that lethal wolf control and maternal caribou penning provide the most effective ways to stabilize population declines. Here we show that this inference was based on an unbalanced analytical approach that omitted a null scenario, excluded potentially confounding variables and employed irreproducible habitat alteration metrics. Our reanalysis of available data shows that ecotype identity is a better predictor of population trends than any adaptive management treatments considered by Serrouya et al. Disparate behavioural characteristics and responses to industrial disturbance among ecotypes suggest it may be incorrect to assume that adaptive management strategies that might benefit one ecotype are transferable to another.

The phylogeny of the Lecanora varia group is inferred from ITS sequences using Bayesian and ML phylogenetic analysis methods. According to our data, usnic acid-containing, corticolous Lecanora species do not form a monophyletic group but occur in three major clades together with other groups of Lecanora and Protoparmeliopsis. The new combination Lecanora filamentosa (Stirt.) Elix & Palice is proposed. The new species Lecanora schizochromatica is described from northwestern North America. It produces atranorin as a major substance and is closely related to the morphologically and chemically similar L. filamentosa. The American Biatora pullula Tuck. is synonymised with Lecanora anopta Nyl., which is hereby reported for continental North America for the first time. The phylogenetic relationships between the major clades of Lecanora are still largely unresolved and require more intensive taxon and character sampling. peerReviewed

The montane and subalpine forests of a mountain range in northwestern Montana were investigated using phytosociological and numerical methods. Twelve associations and two subassociations were identified, of which eight are described here for the first time. The forest vegetation of valleys and lower slopes is strongly affected by repeated fire and is placed in the new orderCalamagrostio-Pseudotsugetalia glaucae, which includes temperate, low elevation forests in inland regions of northwestern North America. These forests bear only weak resemblance to forests traditionally assigned to the classVaccinio-Piceetea, and occupy the habitats filled by broad-leaved forests elsewhere at temperate latitudes. Montane and subalpine forest vegetation is moister and has longer snow duration and a shorter growing season. Upper montane vegetation more closely resembles that of other temperate montane forests of the classVaccinio-Piceetea.

An overview of the montane and subalpine forests ofAbies lasiocarpa, Picea engelmannii, Abies amabilis andTsuga mertensiana of northwestern North America is provided based on 541 releves of forest vegetation from coastal and inland British Columbia, Washington and northwestern Montana. A new classification is proposed based on an examination of the floristic patterns across these communities. Owing to their broadscale floristic similarities, coastal subalpineAbies amabilis-Tsuga mertensiana forests and inland forests ofAbies lasiocarpa, Picea engelmannii, P. glauca, Thuja plicata andTsuga heterophylla are combined into a single order,Thujetalia plicatae. The floristic patterns within this order in turn support the recognition of four alliances. These are (1)Tsugion mertensianae, including coastal and inland subalpine forests ofTsuga mertensiana, Abies amabilis, A. lasiocarpa andPicea engelmannii, with deep winter snowpacks and an often luxuriously developed shrub layer; (2)Abieti-Tsugion heterophyllae all. nov., including mesic inland montaneThuja plicata-Tsuga heterophylla andAbies lasiocarpa-Picea engelmannii forests and related southern borealAbies lasiocarpa-Picea glauca communities; (3)Gymnocarpio-Abietion lasiocarpae, including moist coastal and inland forests dominated by a fern-rich understory andOplopanax horridus; and (4)Lysichito-Chamaecyparidion nootkatensis, which includes wet coastal subalpine forests withLysichiton americanum. A total of five new associations are described, bringing the number of recognized associations within the order to twenty-five. An extensive synonymy and crosswalk to other classification systems is provided.