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Huber, D. P. W.

Publications and source records attributed to Huber, D. P. W..

4 recordsLinked to original sources

Keys to the cabinet: unlocking biodiversity data in public entomology collections

Canadian entomology collections contain valuable biodiversity and ecological data, but they must be digitized in order to be usable by those working outside of the collections. Multiple analyses of the digital database of the Odonata collection at the Royal British Columbia Museum were conducted. These analyses reveal that complete digital datasets can be used to explore questions of historical and current geographical distribution and species composition differences based on ecoprovince and elevation. The results of these analyses can be used directly in conservation and climate change impact mitigation decisions. These analyses are only possible because the Odonata collection has received concerted effort to digitize all specimen records. The full value of long-term historical insect biodiversity data can only be accessed once collections are digitized. Additional training and employment of collection management and curatorial staff is essential to optimize the use of abundant, but underutilized, Canadian biodiversity data.

ecology↗

In-Flights of Outbreak Populations of Mountain Pine Beetle Alter the Local Genetic Structure of Established Populations a Decade After Range Expansion

Mountain pine beetles began to appear at epidemic levels in Alberta, Canada, in 2006, following six years of extensive outbreaks in neighboring British Columbia. We assessed the effect of genetic MPB in-flights from the peak of the outbreak on the genetic structure of established populations of MPB and the change over time in novel regions colonized by these inflights. We used five locations sampled during the peak of the outbreak (2005/2007) and re-sampled in 2016. We performed a ddRADseq protocol to generate a SNP dataset via single-end Illumina sequencing. We detected a northern and southern genetic cluster in both sampling sets (2005/2007 and 2016) and a demographic shift in cluster assignment after [~]10 generations from south to north in two of the sites in the path of the northern outbreak. Fst values were significantly different between most sites in the same years and between the same sites at different years, with some exceptions for northern sites established by inflights. Overall, sites in the spreading path of the MPB outbreak have taken on the genetic structure of the contiguous northern outbreak except for an isolated site in Golden, BC, and in Mount Robson Provincial Park where populations are admixed between north and south. Our results suggest that range expansion during insect outbreaks can alter the genetic structure of established populations and lead to interbreeding between populations.

genomics↗

The phoretic mite (Arachnida: Acari) assemblage of the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins (Coleoptera: Curculionidae)

The phoretic mite assemblage of the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins (Coleoptera: Curculionidae) has not been as thoroughly documented as that of some other ecologically and economically important bark beetle species. Phoretic mites can impact individual fitness and population dynamics of their hosts and documenting the mite assemblage associated with a bark beetle may provide information on their ecological and interactive roles. We caught Douglas-fir beetles over two summers in central British Columbia, Canada and sorted the associated mites into morphospecies. Representatives of the morphospecies were DNA barcoded (cytochrome oxidate I barcode region) which indicated at least nine distinct Operational Taxonomic Units (OTUs). There was a mean of 50.5 {+/-} 4.7 mites per beetle with both females and males carrying similar numbers of most mite species. However one OTU (Sarcoptiformes: Hemisarcoptidae) was found in substantially higher numbers than all other OTUs, and was always clustered in large aggregations in an anterior pocket on the sub-elytral surface. When B1 was removed from the mean, there were only 1.3 {+/-} 0.2 mites per beetle. The consistent high numbers of that OTU in conjunction with its consistent anatomical aggregation suggests an important interaction between that mite species and the Douglas-fir beetle.

ecology↗

Autumn shifts in cold tolerance metabolites in overwintering adult mountain pine beetles

The mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae) is a major forest pest of pines in western North America. Beetles typically undergo a one-year life cycle with larval cold hardening in preparation for overwintering. Two-year life cycle beetles have been observed but not closely studied. This study tracks cold-hardening and preparation for overwintering by adult MPB in their natal galleries. Adults were collected in situ between September and December (2016) for a total of nine time points during 91 days. Concentrations of 41 metabolites in these pooled samples were assessed using quantitative NMR. Levels of glycerol and proline increased significantly with lowering temperature during the autumn. Newly eclosed mountain pine beetles prepare for winter by generating the same cold-tolerance compounds found in larvae, but high on-site mortality suggested that two-year life cycle adults have a less efficacious acclimation process. This is the first documentation of cold acclimation metabolite production in overwintering new adult beetles and is evidence of physiological plasticity that would allow evolution by natural selection of alternate life cycles (shortened or lengthened) under a changing climate or during expansion into new geoclimatic areas.

ecology↗