02394nas a2200193   4500008004100000020001400041245014600055210006900201260000800270300001400278490000700292520163900299653002801938100003501966700002302001700001902024700002202043856013502065       2011                        eng d  a0921-297300aIncoming! Association of landscape features with dispersing mountain pine beetle populations during a range expansion event in western Canada0 aIncoming Association of landscape features with dispersing mount  cOct  a1097-11100 v263 aMountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae), is a forest insect that undergoes intermittent population eruptions, causing landscape-level mortality to mature pines. Currently, an outbreak covers over 16.3 million ha of British Columbia and Alberta in western Canada. Recent incursion into the jack pine (Pinus banksiana Lamb.) of northwestern Alberta threatens further range expansion through the boreal forest to central and eastern Canada. The spread from British Columbia into northwestern Alberta has been facilitated by above-canopy dispersal of the insect by meso-scale atmospheric currents. At these scales, dispersing D. ponderosae may behave like inert particles, causing terrain-induced tropospheric convective and advective currents to influence population dispersal and establishment. We use spatial point process regression models to examine the association of meso-scale variables, including landscape features and their orientations, habitat suitability, elevation and treatment efforts, with occurrence of D. ponderosae infestations in 2004, 2005, and 2006. Infestations of D. ponderosae primarily established in canyons and valleys, before moving into more open-sloped areas. Southwestern slopes of midslope ridges and small hills, southwest facing open slopes, and valleys that run in a northeast-southwest cardinal direction were positively associated with higher intensities of infestation. This study provides insight into the influences of complex terrain on landscape disturbance by a forest insect, and can be used to prioritize areas for potential management.10aDendroctonus ponderosae1 ade la Giroday, Honey-Marie, C.1 aCarroll, Allan, L.1 aLindgren, B.S.1 aAukema, Brian, H.  uhttps://weevil.myspecies.info/incoming-association-landscape-features-dispersing-mountain-pine-beetle-populations-during-range-exp02735nas a2200181   4500008004100000020001400041245012100055210006900176260000800245300001400253490000700267520203800274653002802312100003502340700002302375700002202398856013302420       2012                        eng d  a0305-027000aBreach of the northern Rocky Mountain geoclimatic barrier: initiation of range expansion by the mountain pine beetle0 aBreach of the northern Rocky Mountain geoclimatic barrier initia  cJun  a1112-11230 v393 aAim Our aim is to examine the historical breach of the geoclimatic barrier of the Rocky Mountains by the mountain pine beetle (Dendroctonus ponderosae Hopkins). This recent range expansion from west of the North American continental divide into the eastern boreal forest threatens to provide a conduit to naive pine hosts in eastern North America. We examine the initial expansion events and determine potential mechanism(s) of spread by comparing spread patterns in consecutive years to various dispersal hypotheses such as: (1) meso-scale atmospheric dispersal of insects from source populations south-west of the Rocky Mountains in British Columbia (i.e. their historical range), (2) anthropogenic transport of infested plant material, and (3) spread of insect populations across adjacent stands via corridors of suitable habitat. Location British Columbia, Canada. Methods We explore potential mechanism(s) of invasion of the mountain pine beetle using spatial point process models for the initial 3 years of landscape-level data collection, 2004-2006. Specifically, we examine observed patterns of infestation relative to covariates reflecting various dispersal hypotheses. We select the most parsimonious models for each of the initial 3 years of invasion using information criteria statistics. Results The initial range expansion and invasion of the beetle was characterized by aerial deposition along a strong north-west to south-east gradient, with additional aerial deposition and localized dispersal from persisting populations in following years. Main conclusions Following deposition of a wave front of mountain pine beetles parallel to the Rocky Mountains via meso-scale atmospheric dispersal, the areas of highest intensity of infestations advanced up to 25 km north-east towards jack pine (Pinus banksiana) habitat in a single year. There appeared to be no association between putative anthropogenic movement of infested materials and initial range expansion of the mountain pine beetle across the continental divide.10aDendroctonus ponderosae1 ade la Giroday, Honey-Marie, C.1 aCarroll, Allan, L.1 aAukema, Brian, H.  uhttps://weevil.myspecies.info/breach-northern-rocky-mountain-geoclimatic-barrier-initiation-range-expansion-mountain-pine-beetle02859nas 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-naive02384nas a2200181   4500008004100000020001400041245018200055210006900237260000800306300001200314490000800326520163700334653002801971100002001999700002302019700002502042856013502067       2010                        eng d  a0008-347X00aDifferences in the constitutive terpene profile of lodgepole pine across a geographical range in British Columbia, and correlation with historical attack by mountain pine beetle0 aDifferences in the constitutive terpene profile of lodgepole pin  cNov  a557-5730 v1423 aThe mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), is a destructive insect pest in western Nearctic conifer forests. Currently, British Columbia, Canada, is experiencing the largest recorded outbreak of this insect, including areas that historically have had low climatic suitability for it. We analyzed 26 constitutive resin terpenes in phloem samples from British Columbia lodgepole pine (Pinus contorta) populations to test for differential resistance to mountain pine beetle attack, based upon the likelihood of previous exposure to mountain pine beetle. We assessed sampled trees for number of mountain pine beetle attacks, number of pupal chambers, and tree survival the following spring. Significant differences were found when levels of certain terpenes in lodgepole pine populations that had likely experienced substantial mountain pine beetle infestations in the past were compared with those in populations that likely had not experienced large outbreaks of mountain pine beetle. Although we expected southern pine populations to contain more total terpenes than northern populations, owing to higher historical exposure to the beetle, the converse was found. Northern populations generally had higher levels of constitutive terpenes and beetle attack than southern populations. Because several terpenes are kairomones to the mountain pine beetle and also serve as precursors for the synthesis of pheromones, the lower levels of terpenes expressed by lodgepole pines from the historical range of the mountain pine beetle may render them less chemically perceptible to foraging beetles.10aDendroctonus ponderosae1 aClark, Erin, L.1 aCarroll, Allan, L.1 aHuber, Dezene, P. W.  uhttps://weevil.myspecies.info/differences-constitutive-terpene-profile-lodgepole-pine-across-geographical-range-british-columbia-a02390nas a2200205   4500008004100000020001400041245013400055210006900189260000800258300001400266490000700280520162500287653002801912100002101940700002201961700002001983700002302003700002302026856013502049       2011                        eng d  a0045-506700aEfficacy of tree defense physiology varies with bark beetle population density: a basis for positive feedback in eruptive species0 aEfficacy of tree defense physiology varies with bark beetle popu  cJun  a1174-11880 v413 aWe evaluated the ability of constitutive and inducible defenses to protect trees and restrict herbivore reproduction across the endemic, incipient (i.e., transitory), and eruptive phases of a native bark beetle species. Host defenses were major constraints when mountain pine beetle (Dendroctonus ponderosae Hopkins) populations were low, but inconsequential after stand-level densities surpassed a critical threshold. We annually examined all lodgepole pines (Pinus contorta Douglas var. latifolia) in six 12-18 ha stands for 3-6 years for beetle attack and establishment as beetle densities progressed through various population phases. We also assayed a suite of tree physiological and chemical attributes and related them to subsequent attacks during that year. Rapidly inducible defenses appeared more important than constitutive defenses, and total monoterpenes were more important than particular constituents. Trees that exude more resin and accumulate higher monoterpene concentrations in response to simulated attack largely escaped natural attacks when populations were low. In stands where beetles had reached incipient densities, these defenses were ineffective. Larger diameter trees had more pronounced defenses than smaller diameter trees. As populations increased, beetles selected increasingly larger, more resource-rich trees, despite their better defenses. When populations were too low for cooperative attack, beetles exploited trees weakened by lower-stem insects. Behavioral plasticity allows beetles to persist at endemic levels until conditions shift, after which positive feedbacks predominate.10aDendroctonus ponderosae1 aBoone, Celia, K.1 aAukema, Brian, H.1 aBohlmann, Joerg1 aCarroll, Allan, L.1 aRaffa, Kenneth, F.  uhttps://weevil.myspecies.info/efficacy-tree-defense-physiology-varies-bark-beetle-population-density-basis-positive-feedback-erupt02415nas a2200241   4500008004500000020001400045245011200059210006900171260000900240300001200249490000700261520158700268653002801855100002201883700002301905700001901928700001301947700002301960700001501983700001901998700002402017856013202041       2008                        Engldsh    a0906-759000aMovement of outbreak populations of mountain pine beetle: influences of spatiotemporal patterns and climate0 aMovement of outbreak populations of mountain pine beetle influen  cJune  a348-3580 v313 aInsect outbreaks exert landscape-level influences, yet quantifying the relative contributions of various exogenous and endogenous factors that contribute to their pattern and spread remains elusive. We examine an outbreak of mountain pine beetle covering an 800 thousand ha area on the Chilcotin Plateau of British Columbia, Canada, during the 1970s and early 1980s. We present a model that incorporates the spatial and temporal arrangements of outbreaking insect populations, as well as various climatic factors that influence insect development. Onsets of eruptions of mountain pine beetle demonstrated landscape-level synchrony. On average, the presence of outbreaking populations was highly correlated with outbreaking populations within the nearest 18 km the same year and local populations within 6 km in the previous two years. After incorporating these spatial and temporal dependencies, we found that increasing temperatures contributed to explaining outbreak probabilities during this 15 yr outbreak. During collapse years, landscape-level synchrony declined while local synchrony values remained high, suggesting that in some areas host depletion was contributing to population decline. Model forecasts of outbreak propensity one year in advance at a 12 by 12 km scale provided 80% accuracy over the landscape, and never underestimated the occurrence of locally outbreaking populations. This model provides a flexible approach for linking temperature and insect population dynamics to spatial spread, and complements existing decision support tools for resource managers.10aDendroctonus ponderosae1 aAukema, Brian, H.1 aCarroll, Allan, L.1 aZheng, Yanbing1 aZhu, Jun1 aRaffa, Kenneth, F.1 aMoore, Dan1 aStahl, Kerstin1 aTaylor, Stephen, W.  uhttps://weevil.myspecies.info/movement-outbreak-populations-mountain-pine-beetle-influences-spatiotemporal-patterns-and-climate01400nas a2200193   4500008004500000020001400045245010400059210006900163260001000232300001000242490000700252520071500259653002800974100001301002700001901015700002301034700002201057856012701079       2008                        Engldsh    a1085-711700aAutologistic regression analysis of spatial-temporal binary data via Monte Carlo maximum likelihood0 aAutologistic regression analysis of spatialtemporal binary data   cMarch  a84-980 v133 aThis article considers logistic regression analysis of binary data that are measured on a spatial lattice and repeatedly over discrete time points. We propose a spatial-temporal autologistic regression model and draw statistical inference via maximum likelihood. Due to an unknown normalizing constant in the likelihood function, we use Monte Carlo to obtain maximum likelihood estimates of the model parameters and predictive distributions at future time points. We also use path sampling to estimate the unknown normalizing constant and approximate an information criterion for model assessment. The methodology is illustrated by the analysis of a dataset of mountain pine beetle outbreaks in western Canada.10aDendroctonus ponderosae1 aZhu, Jun1 aZheng, Yanbing1 aCarroll, Allan, L.1 aAukema, Brian, H.  uhttps://weevil.myspecies.info/autologistic-regression-analysis-spatial-temporal-binary-data-monte-carlo-maximum-likelihood