02311nas a2200181   4500008004100000020001400041245011600055210006900171260000800240300001200248490000700260520163400267653002101901100002901922700002201951700002201973856013401995       2010                        eng d  a0046-225X00aSeeing the Forest Through the Trees: Differential Dispersal of Hylobius warreni Within Modified Forest Habitats0 aSeeing the Forest Through the Trees Differential Dispersal of Hy  cJun  a898-9060 v393 aHylobius warreni Wood, also known as the Warren root collar weevil, is a flightless insect that feeds on conifers throughout the boreal forests of Canada. Mature trees typically can withstand feeding, but larval feeding around the root collar may cause mortality to young trees. Recently, a large outbreak of mountain pine beetle (Dendroctonus ponderosae Hopkins) has killed a high proportion of mature lodgepole pine (Pinus contorta Douglas variety latifolia) across British Columbia, Canada. This raises concerns that adult weevils may migrate from mature forests with reduced host pools into adjacent young forests that had been salvaged and replanted. To study movement of these walking weevils in different habitat types, we constructed three research plots consisting of various combinations of live-, dead-, and mixed (i.e., live and dead) -tree habitats. We observed dispersal patterns of individually labeled insects using a novel insect trap attached to the base of trees. Approximately 35% of insects were recaptured over 1 mo. Weevils were least likely to be recaptured proximate to the release location when released in a habitat with dead trees. Movement rates therein were almost double the rates of insects moving through live- or mixed-tree habitats. Our findings support the hypothesis that H. warreni may disperse out of habitats with dead trees into areas with higher proportions of green trees. Our findings are discussed in the context of habitat discrimination and potential increases in herbivory by H. warreni in western Canada given salvage harvesting activities after outbreaks of mountain pine beetle.10aHylobius warreni1 aKlingenberg, Matthew, D.1 aBjorklund, Niklas1 aAukema, Brian, H.  uhttps://weevil.myspecies.info/seeing-forest-through-trees-differential-dispersal-hylobius-warreni-within-modified-forest-habitats02859nas a2200193   4500008004100000020001400041245013900055210006900194260000800263300001400271490000700285520212200292653002802414100002502442700002202467700002302489700001902512856013402531       2010                        eng d  a0021-890100aClimate change and range expansion of an aggressive bark beetle: evidence of higher beetle reproduction in naive host tree populations0 aClimate change and range expansion of an aggressive bark beetle   cOct  a1036-10430 v473 a1. Hosts may evolve defences that make them less susceptible and suitable to herbivores impacting their fitness. Due to climate change-driven range expansion, herbivores are encountering naive host populations with increasing frequency. 2. Aggressive bark beetles are among the most important agents of disturbance in coniferous forest ecosystems. The presence of bark beetle outbreaks in areas with a historically unsuitable climate, in part a consequence of climate change, provided an opportunity to assess the hypothesis that the mountain pine beetle Dendroctonus ponderosae has higher reproductive success in lodgepole pine Pinus contorta trees growing in areas that have not previously experienced frequent outbreaks. 3. We felled and sampled mountain pine beetle-killed trees from historically climatically suitable and unsuitable areas, i.e. areas with and without a historical probability of frequent outbreaks. Reproductive success was determined from a total of 166 trees from 14 stands. 4. Brood productivity was significantly affected by climatic suitability class, such that mean brood production per female increased as historical climatic suitability decreased. 5. Synthesis and applications. The current study demonstrates that the mountain pine beetle has higher reproductive success in areas where its host trees have not experienced frequent beetle epidemics, which includes much of the current outbreak area in north central British Columbia. This increased productivity of mountain pine beetle is likely to have been a key reason for the rapid population buildup that resulted in unprecedented host tree mortality over huge areas in western Canada. The outbreak thus provides an example of how climate change-driven range expansion of native forest insects can have potentially disastrous consequences. Since an increased reproductive success is likely to accelerate the progression of outbreaks, it is particularly critical to manage forests for the maintenance of a mosaic of species and age classes at the landscape level in areas where host tree populations are naive to eruptive herbivores.10aDendroctonus ponderosae1 aCudmore, Timothy, J.1 aBjorklund, Niklas1 aCarroll, Allan, L.1 aLindgren, B.S.  uhttps://weevil.myspecies.info/climate-change-and-range-expansion-aggressive-bark-beetle-evidence-higher-beetle-reproduction-naive02035nas a2200169   4500008004100000020001400041245016700055210006900222260000800291300001200299490000700311520134300318653002801661100002201689700001901711856013501730       2009                        eng d  a0045-506700aDiameter of lodgepole pine and mortality caused by the mountain pine beetle: factors that influence their relationship and applicability for susceptibility rating0 aDiameter of lodgepole pine and mortality caused by the mountain   cMay  a908-9160 v393 a<p>During outbreaks the mountain pine beetle (Dendroctonus ponderosae Hopkins) kills large lodgepole pine trees (Pinus contorta Dougl. ex Loud.) more frequently than smaller ones. There is, however, considerable variation in the relation of diameter to incidence of attack. In a meta- analysis of published data we found that the relationship was primarily determined by geographic location (elevation, latitude, and longitude). We propose a new tree mortality measure, the probability of death index, defined as the average percentage of mortality for trees &gt;23 cm. The index may improve the precision in predictive modeling of tree mortality, as it provides a biologically relevant measure of mortality, since it only includes trees that contribute to the growth of an epidemic and is not influenced by the number of trees within a diameter class. To be useful to forest managers, it must be possible to predict the index from stand parameters that are easily meas- ured. The usefulness of the index was supported by a meta- analysis, which showed that 53% of the variation in the mortal- ity index was explained by geographic location. Tree density did not explain any additional variation. Future research is needed to evaluate the performance of the probability of death index compared with that of other mortality measures.</p>
10aDendroctonus ponderosae1 aBjorklund, Niklas1 aLindgren, B.S.  uhttps://weevil.myspecies.info/diameter-lodgepole-pine-and-mortality-caused-mountain-pine-beetle-factors-influence-their-relationsh01512nas a2200193   4500008004100000020001400041245011000055210006900165260001500234300001200249490000800261520081000269653002801079100002201107700001901129700002101148700001701169856013201186       2009                        eng d  a0378-112700aCan predicted mountain pine beetle net production be used to improve stand prioritization for management?0 aCan predicted mountain pine beetle net production be used to imp  cJanuary 20  a233-2370 v2573 aStand-level planning of lodgepole pine management can benefit from the use of mountain pine beetle susceptibility-riskmodel analyses to assign treatment priority. Priority is currently assigned based solely on relative levels of expected volume loss in the event of a mountain pine beetle outbreak.We evaluated the possibility to predict the relative contribution of brood beetles, by infested stands, to the next beetle generation. Existing data were used to develop generalized parameters for inclusion in predictive models of stand-level mortality and brood production. Model output for independent stands achieved a highly significant relationship with measured outcomes of brood productivity, indicating that relative levels of brood production can be predicted and incorporated into decision-models.10aDendroctonus ponderosae1 aBjorklund, Niklas1 aLindgren, B.S.1 aShore, Terry, L.1 aCudmore, Tim  uhttps://weevil.myspecies.info/can-predicted-mountain-pine-beetle-net-production-be-used-improve-stand-prioritization-management01024nas a2200157   4500008004100000020001400041245012700055210006900182260001600251300001200267490000800279520040100287653002100688100002200709856013500731       2009                        eng d  a0008-347X00aNon-destructive tree-trunk funnel trap for capturing Hylobius warreni (Coleoptera: Curculionidae) ascending stems of trees0 aNondestructive treetrunk funnel trap for capturing Hylobius warr  cJuly-August  a422-4240 v1413 aA simple and inexpensive non-destructive trap to catch insects as they ascend tree boles is described. The trap was tested in a capture-mark-recapture experiment on the Warren root collar weevil, Hylobius warreni Wood. A high percentage (77%) of marked H. warreni were recaptured at least once during a 12-day period and 54% were recaptured more than once, with one weevil recaptured eight times.10aHylobius warreni1 aBjorklund, Niklas  uhttps://weevil.myspecies.info/non-destructive-tree-trunk-funnel-trap-capturing-hylobius-warreni-coleoptera-curculionidae-ascending01808nas a2200157   4500008004500000020001400045245005000059210005000109260001200159300000900171490000700180520134900187653002101536100002201557856007101579       2008                        Engldsh    a0892-755300aCues for shelter use in a phytophagous insect0 aCues for shelter use in a phytophagous insect  cJanuary  a9-230 v213 aMany insects spend a large proportion of their life inactive, often hiding in shelters. The presence of shelters may, therefore, influence where insects feed. This study examines stimuli affecting the use of shelters by adults of the pine weevil, Hylobius abietis (L.) (Coleoptera, Curculionidae). This species is an economically important forest pest in Europe since the adults feed on the stem bark of newly planted conifer seedlings. When there are hiding or burrowing places present in close proximity to a seedling, pine weevils may hide there and repeatedly return to feed on the same seedling. Experiments were conducted in a laboratory arena with above-ground or below-ground shelters and in the presence or absence of wind. Pine weevils were highly attracted to shelters both above and below ground. Weevils in shelters were often observed assuming a characteristic ''resting'' posture. Experiments with opaque and transparent shelters showed that visual stimuli are used for orientation towards shelters and also increase the probability of an individual remaining in a shelter. The presence of wind increased the weevils' propensity to use shelters both above and below ground. The present study indicates that shelters have a major influence on the behavior of the pine weevil and possible implications of the results are discussed.10aHylobius abietis1 aBjorklund, Niklas  uhttps://weevil.myspecies.info/cues-shelter-use-phytophagous-insect