Much of Canada's terrestrial biodiversity is supported by boreal forests. Natural resource development in boreal forests poses risks to this biodiversity. This paper reviews the scientific literature to assess the effects of natural resource development on terrestrial biodiversity in Canadian boreal forests. We address four questions: (1) To what extent have Canadian boreal forests changed due to natural resource development? (2) How has biodiversity responded to these changes? (3) Will the biodiversity of second-growth forests converge with that of primary boreal forests? (4) Are we losing species from boreal forests? We focus on trees, understory plants, insects, fungi, selected mammals, and songbirds because these groups have been most studied. We review more than 600 studies and found that changes in community composition are prevalent in response to large-scale conversion of forest types, changes in stand structures and age distributions, and altered landscape structure resulting from forest management and habitat loss associated with other developments such as oil and gas, hydroelectric, and mining. The southern boreal forest has been more highly impacted than the north due to more extensive forest management and the cumulative effects of multiple forms of development. There is abundant evidence that most species are not in danger of being extirpated from the boreal forest due to these anthropogenic changes. A few species, including woodland caribou (Rangifer tarandus) and grizzly bear (Ursus arctos), have, however, undergone long-term range contractions. Significant gaps in our ability to assess the effects of natural resource development on biodiversity in the boreal zone are the lack of long-term spatial and population data to monitor the impact of forest changes on ecosystems and species.Résumé : Une bonne partie de la biodiversité du Canada se retrouve en forêt boréale. Le développement des ressources naturelles dans des forêts boréales présente des risques pour cette biodiversité. Les auteurs présentent une revue de la littérature pour évaluer les effets du développement des ressources naturelles sur la biodiversité terrestre dans les forêts boréales canadiennes. Ils ont soulevé quatre questions : (1) jusqu'à quel point les forêts boréales canadiennes se sont vues modifiées par le développe-ment des ressources naturelles ? (2) Comment la biodiversité a-t-elle réagi à ces changements ? (3) Y aura-t-il convergence de la biodiversité des forêts de seconde venue avec celle des forêts boréales primaires ? (4) Subissons-nous des pertes d'espèces en forêts boréales ? Les auteurs se sont intéressés en particulier aux arbres, aux plantes de sous-bois, aux insectes, aux champignons, à des mammifères et oiseaux chanteurs sélectionnés, car ces groupes ont été les plus étudiés. Ils ont suivi plus de 600 espèces et ont constaté que les changements de composition prévalent en réaction à des modifications à grande échelle des types forestiers, des changements de la structure, des classes d'âge, des modifications aux ...

Monitoring of forest songbirds via auditory detections during point surveys can be enhanced by using preprogrammed recording devices. During May–July 2008, we compared boreal forest bird surveys conducted with SM‐1 bird song recorders (Wildlife Acoustics, Inc.) with field surveys by observers and surveys recorded with the E3A Bio‐Acoustic Monitor Kit (River Forks Research Corp.) in Ontario, Canada, to evaluate the utility of the SM‐1 to generate reliable detections of forest birds. The SM‐1 surveys identified, on average, 8.95 species, 0.76 fewer species per 10‐min point count than field surveys (${\bar {x}}$ = 9.71 species) and 1.26 fewer species than the E3A (${\bar {x}}$ = 10.21 species). SM‐1 surveys also identified on average 11.6 individuals per 10‐min count, 2.5 fewer than field surveys (${\bar {x}}$ = 14.1) and 2.3 fewer than E3A surveys (${\bar {x}}$ = 13.9), respectively. The lower number of SM‐1 detections, however, was less than the reduction in detections made by field surveys later as compared to earlier in the breeding season. This suggests that SM‐1 recorders set up early in the season would detect more birds than field surveys stretching late into the season. Moreover, lower detections with the SM‐1 could be easily offset by collecting an additional 10‐min sample on another day. Most species were detected equally well by all 3 methods with a few exceptions. Unattended recording devices are especially advantageous in situations where the number of experienced observers is limited, where access difficult, where multiple samples at the same site are desirable, and where it is desirable to eliminate inter‐observer, time‐of‐day and time‐of‐season effects. © 2011 The Wildlife Society.

Artificial nest experiments have been used in an attempt to understand patterns of predation affecting natural nests. A growing body of literature suggests that neither relative rates nor patterns of predation are the same for artificial and natural nests. We studied nest predation and daily mortality rates and patterns at real and artificial ground and shrub nests to test the validity of artificial nest experiments. We monitored 1667 artificial and 344 natural nests, over seven trials, in three regions, across 58 sites in Ontario. We controlled for many of the factors thought to be responsible for previously reported differences between predation rates on natural and artificial nests. Although artificial nests in our study resembled natural nests, contained eggs of appropriate size, shape, and color of target bird species, and were placed in similar microhabitats as natural nests, the rates of predation on these nests did not parallel rates on natural nests for any region in terms of absolute rate or pattern. Predation rates on artificial nests did not vary between years, as they tended to for natural nests, and the magnitude of predation pressure on artificial ground nests compared with shrub nests did not show the same pattern as that on natural nests. In general, rates of predation on artificial nests were significantly higher than on natural nests. Our results suggest that conclusions derived from artificial nest studies may be unfounded. Given that many influential ideas in predation theory are based on results of artificial nest experiments, it may be time to redo these experiments with natural nests.Resumen: Se han utilizado experimentos con nidos artificiales con la intención de entender los patrones de depredación que afectan a los nidos naturales. La bibliografía sugiere que ni las tasas relativas ni los patrones de depredación son iguales para nidos artificiales y naturales. Estudiamos las tasas y patrones de depredación de nidos y de mortalidad diaria en nidos reales y artificiales sobre el suelo y en matorrales para probar la validez de los experimentos con nidos artificiales. Monitoreamos 1667 nidos artificiales y 344 nidos naturales, en siete pruebas, en tres regiones, en 58 sitios en Notario. Controlamos muchos de los factores que se piensa son responsables de diferencias entre tasas de depredación en nidos naturales y artificiales reportadas previamente. Aunque los nidos artificiales en nuestro estudio se asemejaron a nidos naturales, contenían huevos de tamaño, forma y color adecuados para la especie de ave y fueron colocados en microhábitats 382 Predation Patterns on Artificial and Real NestsBurke et al.similares a los de nidos naturales, las tasas de depredación en estos nidos no fueron similares a las tasas en nidos naturales en ninguna región en términos de tasa o patrón absoluto. Las tasas de depredación en nidos artificiales no variaron de un año a otro, como fue la tendencia en nidos naturales, y la magnitud de la presión de depredación en nidos sobre el suelo comparada con nidos en arbu...

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An aqueous suspension of the nuclear polyhedrosis virus of Lymantria dispar (L.), LdNPV, was fed to third-instar caterpillars of L. dispar and 46 species of nontarget Lepidoptera in four successive. 24- to 48-h doses of 3 × 104 polyhedral inclusion bodies (PIBs) in 2 μL applied to small pellets of artificial diet or isolated surfaces of foliage. Adults of the fly Cyrtophleba coquilletti Aldr., and adult males of the bee Megachile rotundata (Fabr.), were assayed with a single dose of 1.2 × 105 PIBs in 2 μL of 30% sucrose solution. Only those specimens that completely consumed the dose(s) were transferred to appropriate maintenance conditions for 7–10 days whereupon they were frozen. Samples of macerates of experimental specimens were dot-blotted onto nylon membranes on which whole genomic LdNPV DNA-probing and chemiluminescence techniques were used lo show presence of LdNPV DNA. With reference to positive and negative controls, the 48 nontarget species were diagnosed as nonpermissive of LdNPV but the target species was clearly infected. This study demonstrates a high degree of host-specificity of LdNPV.

We conducted a field study to compare the effectiveness of acoustic recordings coupled with automated sound recognition versus traditional point counts in terms of their relative abilities to detect 3 bird species-at-risk in southwestern Ontario, Canada. The comparison was made in 50 woodlots, each of which contained a standard Forest Bird Monitoring Program plot of 5 point-count stations. An automated recording device was present at one of the point-count stations. We found that the automated recording and analysis system worked at least as well as the more traditional point-count method in identifying woodlots containing acadian flycatcher (Empidonax virescens) and cerulean warbler (Setophaga cerulea), but that both methods combined performed better than either method alone. The automated system also required considerably less effort in the field (a difference of 140 min/woodlot) with very little additional effort identifying vocalizations in the lab (approx. 22.5 min/woodlot, for all 3 species combined). The automated system was not as effective in detecting prothonotary warbler (Protonotaria citrea), possibly because the species is much less common in southern Ontario than the other 2 species. Ó 2014 The Wildlife Society.

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