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The current capacity of northern high-latitude forests to sequester carbon has been suggested to be undermined by the potential increase in fire and insect outbreaks. Here we investigate the response of the terrestrial ecosystems in the province of British Columbia (BC), Canada, to the recent large mountain pine beetle (MPB) outbreak that started in 1999 as well as changing climate and continually increasing atmospheric CO2 concentration up to 2050, in a combined framework, using a process-based model. Model simulations suggest that the recent MPB outbreak results in BC's forests accumulating 328 Tg less carbon over the 1999–2020 period. Over this same period changing climate and increasing atmospheric CO2 concentration,...
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Long-term monitoring of the rate of change of mountain pine beetle (Dendroctonus ponderosae Hopkins) populations requires detailed tree-level information over large areas. This information is used to assess the status of an infestation (e.g., increasing, stable, or decreasing), and to select and evaluate mitigation approaches. In this research project, the authors develop and demonstrate a prototype monitoring system, which enables the extrapolation of tree-level estimates of beetle damage from field data to a larger study area using a double sampling approach, and multi-scale, multi-source, high spatial resolution remotely sensed data. The project study area encompasses over 6 million ha and is located at the leading...
BACKGROUND: Despite the ecological and agricultural significance of bumble bees in Alaska, very little is known and published about this important group at the regional level. The objectives of this study were to provide baseline data on species composition, distribution, seasonal biology, and parasites of the genus Bombus at three major agricultural locations within Alaska: Fairbanks, Delta Junction, and Palmer, to lay the groundwork for future research on bumble bee pollination in Alaska. NEW INFORMATION: A total of 8,250 bumble bees representing 18 species was collected from agricultural settings near Delta Junction, Fairbanks, and Palmer, Alaska in 2009 and 2010. Of the 8,250 specimens, 51% were queens, 32.7%...
A phylogenetic analysis of 19 sibling taxa in the Vertigo gouldii group was conducted on 73 individuals sampled across North America using DNA sequence data of the mitochondrial genes cytochrome oxidase subunit 1 (CO1) and 16S ribosomal RNA (16S), and the internal transcribed spacer-2 of the nuclear ribosomal RNA (ITS-2) gene. The results of these analyses were found incongruent with previous taxonomic concepts used to define the V. gouldii group and its composite taxa that were based entirely on conchological features. The mtDNA sequence data suggest that some previous members of the traditional V. gouldii group may be more closely related to V. modesta. They also suggest that V. gouldii may itself consist of seven...
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During 1991-1993 and 1998-1999, a leafblotch miner, Micrurapteryx salicifoliella (Chambers), infested willows (Salix spp.) throughout a vast area in drainages of the Yukon and Kuskokwim Rivers, AK. The insect's biology had not been studied and it was unknown from Alaska. Eggs were laid singly, cemented to the epidermis of undersides of leaves. Hatched larvae mined directly into leaves beneath the chorion. Five instars occurred. Mining by the first three instars created little external evidence of their presence. Fourth and fifth instars, however, created conspicuous necrotic, reddish, blotches that often covered the upper leaf surface of susceptible host willows. Mature larvae exited through slits made on the undersides...
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RÉSUMÉ. Les mollusques d'eau douce constituent une partie imposante du régime alimentaire du corégone à bosse (Coregonus pidschian) et du corégone tschir (C. nasus), deux corégonidés à alimentation benthique. L'analyse récente de pisidies (Sphaeriidae), de valvatidés (Valvatidae) et de lymnéidés (Lymnaeidae) provenant du tractus digestif inférieur de ces poissons a permis de constater que grand nombre de ces mollusques étaient toujours en vie. Le fait d'avoir entièrement survécu dans le passage digestif porterait à croire qu'il s'agirait là d'un mécanisme de dispersion des mollusques d'eau douce qui n'a jamais encore été reconnu. Une étude sur le terrain a été réalisée au moyen de corégones à bosse et de corégones...
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An outbreak of the two-year cycle budworm (Choristoneura biennis Freeman) has caused defoliation damage to interior spruce (Picea engelmannii Parry x P. glauca (Moench)) and subalpine fir (Abies lasiocarpa [Hook.] Nutt.) forests of north central British Columbia for more than 10 yr and was ongoing in 1999. A sample of 429 increment cores from spruce, subalpine fir, and lodgepole pine (Pinus contorta var. latifolia Engelm.) was collected in areas of chronic defoliation, and used in a dendro-ecological study. The objective was to develop accurately dated ring-width chronologies of each species and, by comparing growth rates of the budworm host tree species (spruce and fir) with those of the nonhost pine, to determine...
Population genetic structure is the study of genetic variation in time and space. Traditionally, population genetic structure assessments provide information on the dispersal of species, mating behaviours and the delimitation of species and population boundaries. As such, the study of population genetic structure in bark beetles has become an important step in the ongoing management of outbreak populations. In this chapter, we review the current state of population genetic structure studies as they relate to bark beetles, with a particular emphasis on pine beetles. Furthermore, we show how pine beetle research may lead the way in promoting a more comprehensive and methodologically inclusive approach to explaining...
Dendroctonus ponderosae (Hopkins) or mountain pine beetle is a native bark beetle (Coleoptera: Curculionidae: Scolytinae) that feeds on more than 20 species of pine in western North America. In British Columbia, its principal host is lodgepole pine (Pinus contorta var. latifolia Engelmann). As a "primary" bark beetle, D. ponderosae kills its host at epidemic stages, exerting profound landscape-level mortality. As of 2012, D. ponderosae has caused the loss of 726 million cubic meters of timber, covering an area of 17.5 million hectares of mature pine forest in British Columbia and Alberta. Small diameter hosts are not suitable for D. ponderosae , however, creating a niche for the "secondary" bark beetles, including...
The aleocharine beetles of the Yukon Territory, Canada are reviewed based on material studied since the most recent survey of the territory in 2008. The present contribution recognizes a fauna of 125 species, of which 9 are new to science, 20 represent new territorial records and one represents a new Canadian record. Seventeen species are considered Holarctic, 6 introduced, and 2 species are of undetermined status (Holarctic or adventive). The Yukon fauna is classified in 32 genera and 8 tribes. The new species are: 1) Acrotona horwoodae Klimaszewski & Godin, sp. n.; 2) Atheta (Microdota) microelytrata Klimaszewski & Godin, sp. n.; 3) Atheta (Microdota) riparia Klimaszewski & Godin, sp. n.; 4) Atheta (Datomicra)...
Primary ecosystem services provided by freshwater wetlands in the California Central Valley, USA, include water quality improvement, biodiversity support, and flood storage capacity. We describe these services for freshwater marshes, vernal pools, and riparian wetlands and the implications for wetlands restored under USDA programs in the Central Valley. California's Central Valley is a large sedimentary basin that was once covered by grasslands, extensive riparian forests, and freshwater marshes that today have been converted to one of the most intensive agricultural areas on earth. Remaining freshwater wetlands have been heavily altered, and most are intensively managed. Nitrogen loading from agriculture to surface...
Population genetic structure is the study of genetic variation in time and space. Traditionally, population genetic structure assessments provide information on the dispersal of species, mating behaviours and the delimitation of species and population boundaries. As such, the study of population genetic structure in bark beetles has become an important step in the ongoing management of outbreak populations. In this chapter, we review the current state of population genetic structure studies as they relate to bark beetles, with a particular emphasis on pine beetles. Furthermore, we show how pine beetle research may lead the way in promoting a more comprehensive and methodologically inclusive approach to explaining...
map background search result map search result map Biology of a Willow Leafblotch Miner, Micrurapteryx salicifoliella, (Lepidoptera: Gracillariidae) in Alaska New aquatic insect (Ephemeroptera, Trichoptera, and Plecoptera) records for Alaska, U.S.A.: range extensions and a comment on under-sampled habitats Working paper, monitoring tree-level insect population dynamics with multi-scale and multi-source remote sensing Periodicity of two-year cycle spruce budworm outbreaks in central British Columbia: A Dendro-Ecological analysis Freshwater Mollusks Survive Fish Gut Passage Substrate limitations to microbial activity in taiga forest floors Potential near-future carbon uptake overcomes losses from a large insect outbreak in British Columbia, Canada Substrate limitations to microbial activity in taiga forest floors Freshwater Mollusks Survive Fish Gut Passage Biology of a Willow Leafblotch Miner, Micrurapteryx salicifoliella, (Lepidoptera: Gracillariidae) in Alaska Working paper, monitoring tree-level insect population dynamics with multi-scale and multi-source remote sensing Periodicity of two-year cycle spruce budworm outbreaks in central British Columbia: A Dendro-Ecological analysis New aquatic insect (Ephemeroptera, Trichoptera, and Plecoptera) records for Alaska, U.S.A.: range extensions and a comment on under-sampled habitats Potential near-future carbon uptake overcomes losses from a large insect outbreak in British Columbia, Canada