@article {15274,
	title = {Differences in bark beetle (Ips typographus and Pityogenes chalcographus) abundance in a strict spruce reserve and the surrounding spruce forests of Serbia},
	journal = {Phytoparasitica},
	volume = {38},
	number = {1},
	year = {2010},
	month = {Feb},
	pages = {31-37},
	abstract = {Frequent windthrow in the strict reserves of spruce in the Kopaonik National Park provides much material favorable for the development of Ips typographus (L.) and Pityogenes chalcographus (L.) (Coleoptera, Scolytidae). Therefore it was assumed that the abundance of these bark beetles in the reserves was high and that they dispersed to the surrounding spruce forests. To verify this opinion, their population levels were monitored in the strict reserve Jankove Bare and the adjoining spruce forests over the period 2006-2008. I. typographus parasitoids were identified and the parasitism percent was determined in spruce forests around the reserves. Throughout the monitoring period, the abundance of I. typographus and P. chalcographus was found to be lower in the reserve than in the surrounding spruce forests. Five species of I. typographus parasitoids and a low parasitization percent were identified in spruce forests surrounding the reserve.},
	keywords = {Ips typographus, Pityogenes chalcographus},
	isbn = {0334-2123},
	author = {Markovic, Cedomir and Stojanovic, Aleksandar}
}
@article {15217,
	title = {Distribution of the bark beetle (Ips typographus) and its entomophages along tree trunk},
	journal = {Zoologicheskii Zhurnal},
	volume = {88},
	number = {9},
	year = {2009},
	month = {September},
	pages = {1139-1145},
	abstract = {The data on the distribution of Ips typographus and its entomophages along fallen tree trunks (Tula region) are first presented. The results obtained revealed the presence of some density gradients in the distribution of Ips typographus and its entomophages in the settled part of a fallen tree trunk and correlation between the number of bark beetles and their entomophages.},
	keywords = {Ips typographus},
	isbn = {0044-5134},
	author = {Mamontov, S. N.}
}
@article {14598,
	title = {Differences in bark beetle (Ips typographus and Pityogenes chalcographus) abundance in a strict spruce reserve and the surrounding spruce forests of Serbia},
	journal = {Phytoparasitica},
	volume = {38},
	number = {1},
	year = {2010},
	month = {Feb},
	pages = {31-37},
	abstract = {Frequent windthrow in the strict reserves of spruce in the Kopaonik National Park provides much material favorable for the development of Ips typographus (L.) and Pityogenes chalcographus (L.) (Coleoptera, Scolytidae). Therefore it was assumed that the abundance of these bark beetles in the reserves was high and that they dispersed to the surrounding spruce forests. To verify this opinion, their population levels were monitored in the strict reserve Jankove Bare and the adjoining spruce forests over the period 2006-2008. I. typographus parasitoids were identified and the parasitism percent was determined in spruce forests around the reserves. Throughout the monitoring period, the abundance of I. typographus and P. chalcographus was found to be lower in the reserve than in the surrounding spruce forests. Five species of I. typographus parasitoids and a low parasitization percent were identified in spruce forests surrounding the reserve.},
	keywords = {Ips typographus, Pityogenes chalcographus},
	isbn = {0334-2123},
	author = {Markovic, Cedomir and Stojanovic, Aleksandar}
}
@article {14446,
	title = {Distribution of the bark beetle (Ips typographus) and its entomophages along tree trunk},
	journal = {Zoologicheskii Zhurnal},
	volume = {88},
	number = {9},
	year = {2009},
	month = {September},
	pages = {1139-1145},
	abstract = {The data on the distribution of Ips typographus and its entomophages along fallen tree trunks (Tula region) are first presented. The results obtained revealed the presence of some density gradients in the distribution of Ips typographus and its entomophages in the settled part of a fallen tree trunk and correlation between the number of bark beetles and their entomophages.},
	keywords = {Ips typographus},
	isbn = {0044-5134},
	author = {Mamontov, S. N.}
}
@article {13984,
	title = {Merocoenoses of cambioxylophagous insect fauna of Norway spruce (Picea abies (L.) Karst.) with focus on bark beetles (Coleoptera: Scolytidae) and types of tree damage in different gradation conditions},
	journal = {Journal of Forest Science},
	volume = {56},
	number = {10},
	year = {2010},
	month = {2010},
	pages = {474-484},
	abstract = {Research on merocoenoses of cambioxylophagous insect fauna of Norway spruce (Picea abies (L.) Karst.) was carried out in spruce stands of different age in the area with an endemic population (Moravian-Silesian Beskids, Czech Republic) and in the area with an epidemic population (Beskid Zywiecki, Poland) of the eight-toothed spruce bark beetle Ips typographus (L.). The structure of merocoenoses was characterized separately for standing trees attacked by bark beetles, trees struck by lightning, trees affected by fungal pathogens and wind-felling and trees in the form of snags and fragments. The occurrence of cambioxylophagous insects, mostly bark beetles (Coleoptera: Scolytidae), was compared between the study areas with emphasis on dominant facultative primary bark beetles and types of damage to spruce trees.},
	keywords = {Ips typographus},
	isbn = {1212-4834},
	author = {Kula, E. and Zabecki, W.}
}
@article {13949,
	title = {Bark beetle 2006: situation and monitoring},
	journal = {Forstschutz Aktuell},
	volume = {39},
	year = {2007},
	month = {Juni},
	pages = {8-17},
	abstract = {The efforts to stem the mass bark beetle outbreak in Austria did not defuse the situation. In 2006, bark beetle infested over 2.4 million m3 wood. This record level has now been maintained for four years. The consequence of the wind throw from gales 2007 and the climate of the last half year will not reduce the bark beetle situation. Seven Federal Provinces joined the Austrian Bark Beetle Monitoring. The results from 170 pheromone traps were presented on the bark beetle homepage of the BFW (www.borkenkaefer.at). In 2006, the flight activities in the Federal Provinces and over the various altitudes were almost uniform. In the case of Ips typographus, the flight period started between the beginning and middle of April and reached the maximum in mid-June. In comparing altitude classes, the flight period started later and lasted shorter in case of increasing altitudes. The wind throw from 2002 caused the heaviest damages in the Federal Provinces Salzburg and Styria. In 2006, the amount of bark beetle infested wood showed a different trend in these Federal Provinces. Therefore, the trap results were compared in order to see, if this trend is reflected in the monitoring data.},
	keywords = {Ips typographus},
	isbn = {1815-5111},
	author = {Krehan, Hannes and Steyrer, Gottfried}
}
@article {13950,
	title = {Bark beetle calamity remained topical also in 2007},
	journal = {Forstschutz Aktuell},
	volume = {42},
	year = {2008},
	month = {Mai},
	pages = {8-10},
	type = {Article},
	abstract = {In 2007, 2.14 million m3 of wood were infested by bark beetle. This means a slight decrease of bark beetle damage compared to the year before. However, the record level of 2 million m3 has been exceeded the fifth consecutive year. Due to the massive wind throw from gales early in 2008, bark beetle gradation will remain a topical issue. Seven federal provinces joined the Austrian bark beetle monitoring system consisting of approximately 170 pheromone traps. The flight activity and especially the flight maxi-mum differed considerably. However, the flight showed a very consistent pattern starting early again, as expected.},
	keywords = {Ips typographus, Pityogenes chalcographus},
	isbn = {1815-5111},
	author = {Krehan, Hannes and Steyrer, Gottfried}
}
@article {13948,
	title = {Swarm development of Ips typographus in 2010 in Austria},
	journal = {Forstschutz Aktuell},
	volume = {51},
	year = {2011},
	month = {Februar},
	pages = {8-9},
	abstract = {The cold winter 2009/10 and regionally very humid weather conditions were limiting factors for the development of Ips typographus in 2010. In spite of late start of the first breeding, two generations developed at low and middle altitudes. In the higher altitudes range only one generation would swarm. The development of a second generation should be temporally possible in many places. Therefore, with favorable weather conditions an intense and early flight can be expected in spring 2011.},
	keywords = {Ips typographus},
	isbn = {1815-5103; 1815-5111},
	author = {Krehan, Hannes and Schweiger, Christof and Steyrer, Gottfried and Perny, Bernhard}
}
@article {13915,
	title = {Physiological and biochemical analysis of overwintering and cold tolerance in two Central European populations of the spruce bark beetle, Ips typographus},
	journal = {Journal of Insect Physiology},
	volume = {57},
	number = {8},
	year = {2011},
	month = {August},
	pages = {1136-1146},
	abstract = {Overwintering success is one of the key aspects affecting the development and outbreaks of the spruce bark beetle, Ips typographus (L.) populations. This paper brings detailed analysis of cold tolerance, and its influence on overwintering success, in two Central European populations of I. typographus during two cold seasons. Evidence for a supercooling strategy in overwintering adults is provided. The lower lethal temperature corresponds well to the supercooling point that ranges between -20 and -22 [degree]C during winter months. The supercooled state is stabilized by the absence of internal ice nucleators and by seasonal accumulation of a mixture of sugars and polyols up to the sum concentration of 900 mM. The cryoprotective function of accumulated metabolites is probably based on increasing the osmolality and viscosity of supercooled body fluids and decreasing the relative proportion of water molecules available for lethal formation of ice nuclei. No activity of thermal hysteresis factors (stabilizers of supercooled state) was detected in hemolymph. Lethal times for 50\% mortality (Lts50) in the supercooled state at -5, -10 or -15 [degree]C are weeks (autumn, spring) or even months (winter), suggesting relatively little mortality caused by chill injury. Lts50 at -15 [degree]C are significantly shorter in moist (6.9 days) than in dry (>42 days) microenvironment because there is higher probability of external ice nucleation and occurrence of lethal freezing in the moist situation.},
	keywords = {Ips typographus},
	isbn = {0022-1910},
	author = {Kostal, V. and Dolezal, P. and Rozsypal, J. and Moravcova, M. and Zahradnickova, H. and Simek, P.}
}
@article {13916,
	title = {Multiple component system of sugars and polyols in the overwintering spruce bark beetle, Ips typographus},
	journal = {Journal of Insect Physiology},
	volume = {53},
	number = {6},
	year = {2007},
	month = {June},
	pages = {580-586},
	abstract = {Overwintering adults of the spruce bark beetle, Ips typographus (L.) showed an unusually complex sugar/polyol cryoprotectant system. The major components of the multiple system were: glucose (177.6 mmol L-1, March); trehalose (175.0 mmol L-1, December); sorbitol (147.9 mmol L-1, January); mannitol (81.2 mmol L-1, March); and erythritol (40.7 mmol L-1, March) (in the parentheses, the maximum concentrations are shown and the month when they were reached). Other minor components were glycerol, fructose, threitol, myo-inositol, arabinitol and ribitol. Distinct seasonal patterns of accumulation/depletion in various components were found. Glycerol, trehalose and glucose started to accumulate first, during early autumn, when the air temperatures fluctuated between 20 and 0 [degree]C, and diapause beetles continued in feeding. Glycerol was depleted, glucose remained stable and trehalose continued in accumulation during late autumn when the temperatures oscillated around 0 [degree]C. During early winter severe frosts reaching -20 [degree]C came, the beetles terminated their diapause and trehalose was partially depleted, while mannitol, sorbitol, fructose, threitol and erythritol started to accumulate. Cold weather continued also during late winter when the beetles remained quiescent. During this period, trehalose was re-accumulated, threitol and erythritol continued to increase, mannitol remained stable and sorbitol, fructose decreased. All cryoprotectans were finally cleared in the beetles which were spontaneously leaving bark during early spring. The seasonal maximum of total concentration of all cryoprotectants (578.2 mOsmol L-1) was reached in March. Such a concentration results in colligative depression of melting point of body fluids down by 1.08 [degree]C only. It suggests that the potential cryoprotective effect of accumulated sugars and polyols was related rather to their non-colligative functions},
	keywords = {Ips typographus},
	isbn = {0022-1910},
	author = {Kostal, V. and Zahradnickova, H. and Simek, P. and Zeleny, J.}
}
@article {13737,
	title = {Ips typographus population development after a severe storm in a nature reserve in southern Sweden},
	journal = {Journal of Applied Entomology},
	volume = {135},
	number = {1-2},
	year = {2011},
	month = {February},
	pages = {132-141},
	abstract = {Large-scale natural disturbances pose challenges for the management of protected areas and may have undesirable consequences for commercial plantations nearby. A storm, which felled nearly 10 000 m3 of spruce forest in the Osaby nature reserve in southern Sweden, allowed us to study the subsequent population development of the spruce bark beetle (Ips typographus L.). Two summers after the storm, an exceptionally high proportion (74\%) of wind-felled trees had been successfully colonized by the bark beetle, and all living spruce trees had been killed. On standing trees, colonization density was three times higher, and reproductive success one-fourth, that on wind-felled trees. The negative relationship between colonization density and reproductive success indicates that intra-specific competition is one of the main mechanisms reducing I. typographus population growth when the beetles switch from wind-felled to standing trees after storm disturbances. Indeed, there was no significant difference in beetle production between wind-felled and standing trees. Furthermore, there were no differences in colonization density, reproductive success or production at different heights in standing trees; however, a higher proportion of the new adults emerged at the tree-tops rather than lower down before overwintering. Our results also demonstrate that a large proportion (ca. 50\%) of the I. typographus population that developed in the storm-fell area apparently overwintered under the bark of standing trees.},
	keywords = {Ips typographus},
	isbn = {0931-2048},
	author = {Komonen, A. and Schroeder, L. M. and Weslien, J.}
}
@article {13320,
	title = {Further Studies on the Occurrence of Natural Enemies of Ips typographus (Coleoptera: Curculionidae: Scolytinae) in Georgia},
	journal = {Acta Zoologica Bulgarica},
	volume = {62},
	number = {2},
	year = {2010},
	month = {Aug},
	pages = {131-138},
	abstract = {Natural enemy complex of the bark beetle - Ips typographus, a pest insect of Picea orientalis in Georgia was investigated. Their frequency in different elevation zones and different years in managed and unmanaged forests of Georgia was determined. The protozoan pathogen Gregarina typographi and microsporidium Chytridiopsis typographi were observed in the investigated beetles. While the gregarine was found each year and at every altitude investigated, the microsporidium was observed in beetles with a lower frequncy and not at every studied site. Additionally, a fungal pathogen Fusarium sp. in a low frequency was detected in part of the studied beetles. Nematodes were found free in the haemolymph and in the gut lumen as well but only one nematode species, Contortylenchus diplogaster could be identified. Larvae of the parasitoids Tomicobia seitneri and Ropalophorus clavicornis were also observed at different elevations. Predators Nudobius lent us and Thanasimus formicarius were detected in galleries off typographus. The amount of the pest larvae consumed by both species within twenty four hours was determined under laboratory conditions.},
	keywords = {Ips typographus},
	isbn = {0324-0770},
	author = {Kereselidze, Manana and Wegensteiner, Rudolf and Goginashvili, Nana and Tvaradze, Meri and Pilarska, Daniela}
}
@article {13319,
	title = {Occurrence of pathogens and parasites in Ips typographus L. from spruce stands (Picea orientalis L.) in Georgia},
	journal = {IOBC-WPRS Bulletin},
	volume = {30},
	number = {1},
	year = {2007},
	month = {2007},
	pages = {207-210},
	abstract = {Occurrence of pathogens was investigated in the spruce bark beetle Ips typographus from two different sampling plots in Borjomi region at 900m above sea level, collected in September 2004. Investigations brought evidence of one pathogen species only, Gregarina typographi, was found in the mid-gut lumen of 48.6\% and of 23.2\% of adult beetles respectively. In both cases were more male beetles infected than female beetles. Furthermore, unidentified fungal infections were observed in some few individuals. Relatively few beetles had larvae of the Hymenopteran parasitoids Tomicobia seitneri and Ropalophorus clavicornis. In addition, Contortylenchus typographi nematodes were found in the haemolymph of beetles, and not identified nematode larvae in the gut lumen},
	keywords = {Ips typographus},
	isbn = {1027-3115},
	author = {Kereselidze, Manana and Wegensteiner, Rudolf}
}
@article {13302,
	title = {Quantifying spatio-temporal dispersion of bark beetle infestations in epidemic and non-epidemic conditions},
	journal = {Forest Ecology and Management},
	volume = {262},
	number = {4},
	year = {2011},
	month = {Aug 15},
	pages = {598-608},
	abstract = {Spatio-temporal dispersal of pest species such as bark beetles plays a key role in their population ecology and outbreak dynamics. Understanding the underlying patterns is crucial for applying appropriate management strategies. In contrast to most existing studies which focus on dispersing beetles, we analysed patches of killed trees resulting from bark beetle infestation. The study was based on a 22-year time series of annually captured colour-infrared (CIR) images of the Bavarian Forest National Park (Germany), where Ips typographus L. (Coleoptera, Curculionidae, Scolytinae) propagates undisturbed by human activity. Newly infested patches comprising at least 5 spruce trees were identified in every time step. This investigation of spatio-temporal spread of infestations primarily focused on (i) parameterizing the size and shape of infestation patches, (ii) modelling an infestation gradient and (iii) evaluating the risk of subsequent infestations on landscape scale. We developed a GIS-based distance ring approach to quantify the distance relation of subsequent infestations, including the distribution of potential hosts. Infestation spread was revealed to be strongly distance dependent, following an inverse power law function: on average 65\% of new infestations occurred within a 100 m radius of the previous year{\textquoteright}s infestations, and 95\% within 500 m. {\textquoteright}Distance{\textquoteright} proved to be a major determinant of I. typographus dispersal on the landscape scale in each time step of the 22-year series we investigated. Infestation distance thus describes the outcome of beetle dispersal very accurately. The time series showed two alternating periods of epidemic and non-epidemic infestation. These gradation stages did not affect the size and shape of infested patches, but epidemics correlated significantly with a higher percentage of infestations within short distances. Additionally, the resulting infestation risk is highly sensitive to the gradation stage, particularly within the first 100 m around source spots where it increases up to 30\%. Our study therefore contributes to a better understanding of the outbreak dynamics of I. typographus and suggests concentrating efficient bark beetle management on areas in the close vicinity of previous years{\textquoteright} infestations.},
	keywords = {Ips typographus},
	isbn = {0378-1127},
	author = {Kautz, Markus and Dworschak, Kai and Gruppe, Axel and Schopf, Reinhard}
}
@article {13208,
	title = {Feeding on trees - the Bark Beetles (Coleoptera: Curculionidae, Scolytinae)},
	journal = {Entomologische Zeitschrift},
	volume = {121},
	number = {5},
	year = {2011},
	month = {Oktober},
	pages = {215-220},
	abstract = {Forests, especially those, that consist of ancient trees, offer optimal conditions for these insects: The larvae and adults live on cambium, bark and wood. Especially those trees that are not in healthy condition, pro-vide good opportunities for the secret life of these insects. This beetle-group is a subgroup of the weevils (Curculionidae), and has a high diversity with about 5000 species described world-wide. They often show complex intraspecific communication that operates via chemical messengers, so called pheromones, which is explained by the well known Douglas-fir beetle (Dendroctonus pseudotsugae HoPKINs, 1905). Next to chemical communications also click- and cicada-sounds are used. Furthermore, several other members of this beetle group are mentioned. The European spruce bark beetle (Ips typographus LINNAEUS, 1758) is a well-known example for these beetles, be-cause it sometimes damages high amounts of timber. Bark beetles play an important role in forest ecosystem, but they are also considered as threat for economically used forests. This may be the reason, why these insects are often characterized by dramatic exaggerations.},
	keywords = {Ips typographus},
	isbn = {0013-8843},
	author = {Josten, Daniel}
}
@article {13135,
	title = {Bark beetles after the storm in 2005},
	journal = {Entomologisk Tidskrift},
	volume = {128},
	number = {1-2},
	year = {2007},
	month = {maj},
	pages = {71-72},
	abstract = {After a vast stormfelling (75 million m3) in south Sweden in 2005, the spruce bark beetle (Ips typographus) has had two successful years. First year with large amounts of breeding substrate (wind-felled trees) and the second with extraordinary warm weather. This lead to an outbreak which killed 1,5 million m3 spruces 2006. Several measures to surpress [suppress] the outbreak are done. Some of them may be negative for threatened saproxylic species. In spite of what is done, the development of the bark beetle populations will be largely affected by the weather.},
	keywords = {Ips typographus},
	isbn = {0013-886X},
	author = {Jonsell, Mats}
}
@article {13113,
	title = {The influence of bark beetles outbreak vs. salvage logging on ground layer vegetation in Central European mountain spruce forests},
	journal = {Biological Conservation},
	volume = {141},
	number = {6},
	year = {2008},
	month = {June},
	pages = {1525-1535},
	type = {Article},
	abstract = {Changes in the herb and moss layers of mountain spruce (Picea abies (L.) Karst.) forests after bark beetle (Ips typographus (L.)) outbreak were compared with and without forestry intervention. The study area is situated in the Sumava National Park (Czech Republic, Central Europe), where an extensive bark beetle outbreak occurred in the 1990s. Parts of forests were left without interventions, while salvage logging was applied in other areas. Altogether, 18 permanent research plots were established in: (1) climax stands with completely dead canopy, (2) climax stands where salvage logging was applied (clearcuts), and (3) waterlogged stands with only partly dead canopy. Vegetation composition of the ground layer and species numbers were evaluated in 1997 and 2002. The effect of salvage logging on vegetation was greater than that of the bark beetle outbreak itself. Forest herb species and partly also bryophytes survived relatively well under untouched dead canopy. The fewest changes occurred under the partly dead canopy in waterlogged forests. The herb layer expanded in clearcuts originated due to salvage logging, being dominated by grasses. Bryophytes were more susceptible to logging than herbs; their cover in clearcuts was markedly lower and composition changed towards pioneer species. The results show that a natural succession of mountain spruce forests after a bark beetle outbreak, if left without interventions, will probably avoid a pioneer stage and direct recovery of the forests will be possible. Salvage logging had negative effects on species composition of the spruce forests, delayed the forest recovery, and should not be permitted in the national park.},
	keywords = {Ips typographus},
	isbn = {0006-3207},
	author = {Jonasova, Magda and Prach, Karel}
}
@article {13070,
	title = {Diversity of ophiostomatoid fungi associated with bark beetles (Coleoptera: Scolytidae) colonizing branches of Norway spruce (Picea abies) in southern Poland},
	journal = {Biologia (Bratislava)},
	volume = {64},
	number = {6},
	year = {2009},
	month = {December},
	pages = {1170-1177},
	abstract = {Bark beetles (Coleoptera: Scolytidae) infesting Norway spruce trees are known to be associated with fungi, especially species of Ophiostoma sensu lato and Ceratocystis. However, very little is known about these fungi in Poland. In this study, we examined the ophiostomatoid species associated with seven species of bark beetles developing in Norway spruce (Picea abies). Fungi were isolated from the beetles and their galleries at ten sites in southern Poland. We identified a total of 2,769 fungal isolates that belong to 19 ophiostomatoid species. These 19 species included a total of 16 associations between fungi and bark beetles that had not been previously recorded. The isolated fungal species were similar to those previously reported. The species spectrum and relative abundance of fungal associates were similar in seven bark beetle species, despite some differences between species. Except for Pityophthorus pityographus, all bark beetles species were frequently associated with ophiostomatoid fungi. The most commonly encountered fungal associates of bark beetles were the following: Ophiostoma ainoae, O. bicolor, O. piceae sensu lato and Grosmannia piceiperda. The results support the hypothesis that pathogenic ophiostomatoid fungi are important for aggressive bark beetles to kill trees. The most virulent fungal associate of bark beetles, Ceratocystis polonica was most commonly associated with Ips typographus. The most frequent ophiostomatoid species isolated from the beetles and galleries of P. pityographus were O. ainoae and Graphium fimbriisporum.},
	keywords = {Ips typographus},
	isbn = {0006-3088},
	author = {Jankowiak, Robert and Kacprzyk, Magdalena and Mlynarczyk, Marta}
}
@article {13060,
	title = {Invasive capacity of Ips typographus (Coleoptera, Curculionidae) and the Allee effect.},
	journal = {Bulletin de la Societe Royale Belge d{\textquoteright}Entomologie},
	volume = {144},
	number = {7-12},
	year = {2008},
	month = {Juli-December},
	pages = {172-176},
	type = {Article},
	abstract = {For Ips typographus, wide-range dispersal is an important adaptation for finding scattered and unpredictible resources. The dispersing beetles constitute a "reservoir", fed by multiple sources and spread out over the whole landscape. This study alms to better understand two complementary aspects of migration: Wide-range dispersal, through the analysis of the spatial structure of the reservoir, progressively thinning with the distance from main sources of beetles (infested areas). The experimental approach is a 150 km transect between an area of endemicity (Bouillon and the Belgian Ardenne) and a spruce-free area (Champagne). The catches along the transect show that the reservoir spreads out over the landscape, up to 100 km, and that this reservoir is able to re-concentrate locally over isolated spruce stands.Local dispersal in the absence of any pre-established reservoir, through a mark-release-recapture experiment in a spruce-free (and beetle-free) area (Foret Domaniale de la Perthe, Champagne Ardenne). The recapture rates show that the released population is rapidly thinned out by dispersal: in the absence of any pre-established reservoir, colonization of new resources seems difficult in many instances.},
	keywords = {Ips typographus},
	isbn = {1374-8297},
	author = {Jacquemin, Justine}
}
@article {12369,
	title = {Geographical variability of spruce bark beetle development under climate change in the Czech Republic},
	journal = {Journal of Forest Science},
	volume = {57},
	number = {6},
	year = {2011},
	month = {2011},
	pages = {242-249},
	abstract = {Climate change is expected to influence the distribution and population dynamics of many insect pests, with potential severe impacts on forests. Spruce bark beetle Ips typographus (L.) (Col.: Curculionidae, Scolytinae) is the most important forest insect pest in Europe whose development is strictly regulated by air temperature. Therefore, climate change is anticipated to induce changes in the pest{\textquoteright}s distribution and development. We used the PHENIPS model to evaluate climate change impacts on the distribution and voltinism of spruce bark beetle in the Czech Republic. Two future time periods - 2025-2050 (near future) and 2075-2100 (distant future) - are addressed. The period 1961-1990 is used as the reference. We found that while a two-generation regime dominated in the Czech Republic in the reference period, significant three-generation regime regions are projected to appear in the near future. In the distant future, the three-generation regime can be expected to occur over all existing coniferous stands in the Czech Republic. The analysis of altitudinal shift of n-generation regime regions indicates noticeable expansion of Ips typographus development to higher elevations, leading for example to disappearance of one-generation regime regions in the distant future. Uncertainties and limitations of the presented findings are discussed as well.},
	keywords = {Ips typographus},
	isbn = {1212-4834},
	author = {Hlasny, T. and Zajickova, L. and Turcani, M. and Holusa, J. and Sitkova, Z.}
}
@article {11794,
	title = {The diversity of phoretic Mesostigmata on Ips typographus (Coleoptera: Scolytinae) caught in the Karkonosze forest},
	journal = {European Journal of Entomology},
	volume = {108},
	number = {3},
	year = {2011},
	month = {July 1},
	pages = {489-491},
	abstract = {This study determined the scale of the phoresy of mesostigmatid mite by Ips typographus. Thirty pheromone traps in the Karkonosze National Park (Poland) caught 10,575 bark beetles on which there were 2,388 mesostigmatid mites belonging to eight species. The most numerous mites were Dendrolaelaps quadrisetus (1076 id.) and Trichouropoda polytricha (1067 id.).},
	keywords = {Ips typographus},
	isbn = {1210-5759},
	author = {Gwiazdowicz, Dariusz J. and Kamczyc, Jacek and Bloszyk, Jerzy}
}
@article {11486,
	title = {Efficiency of the bark beetle Ips typographus (L.) pheromone traps installation next to the windfallen and windbroken trees},
	journal = {Lesne Prace Badawcze},
	volume = {69},
	number = {4},
	year = {2008},
	month = {2008},
	pages = {365-370},
	type = {Article},
	keywords = {Ips typographus},
	isbn = {1732-9442},
	author = {Grodzki, Wojciech and Kosibowicz, Mieczyslaw and Maczka, Tomasz}
}
@article {11419,
	title = {Natural regeneration of mixed spruce and fir stand (Abieti-Piceetum) damaged by spruce bark beetles in the area of Knezevo},
	journal = {Sumarstvo},
	volume = {2008},
	number = {3},
	year = {2008},
	month = {2008},
	pages = {53-64},
	type = {Article},
	abstract = {Natural regeneration in a mixed fir and spruce stand (Abieti [long dash] Piceetum) was resea- rched on the areas damaged by spruce bark beetles and reclaimed by clear cutting. The damage occurred in 2003 due to poorly applied forest order. All the infested and dead, mainly spruce trees, damaged by spruce bark beetles (Pityogenes chalcographus and Ips typographus) were removed by clear cutting in the form of irregular circular areas. The degree of regeneration, abundance and the characteristics of fir and spruce young growth were studieddepending on the aspect of the regeneration areas and their sizes. Natural regeneration of firand spruce stands after the reclamation of the damage caused by bark beetles should be adapted to a specific management system, because the differences in fir and spruce bioecological characters require different silvicultural procedures depending on the actual state. By the application of clear cutting in the form of circular areas with eccentric extensions, the conditions of spruce natural regeneration can be improved in the aim of achieving the technical goals of management of mixed fir and spruce forests.},
	keywords = {Ips typographus, Pityogenes chalcographus},
	isbn = {0350-1752},
	author = {Govedar, Zoran and Stanivukovic, Zoran and Zlokapa, Brane}
}
@article {11271,
	title = {Responses of parasitoids to saproxylic hosts and habitat: a multi-scale study using experimental logs},
	journal = {Oecologia (Berlin)},
	volume = {155},
	number = {1},
	year = {2008},
	month = {February},
	pages = {63-74},
	type = {Article},
	abstract = {Species belonging to higher trophic levels are particularly vulnerable to habitat loss and consequential host population declines, but detection of effects depends on observation scale. We investigated the effects of habitat and host availability at multiple scales on parasitoids of early successional saproxylic beetles in middle boreal Sweden, where forestry has led to habitat fragmentation and coarse woody debris (CWD) loss. Parasitoid wasps and beetle hosts were collected from nine locations, each containing three spruce-dominated stand types (clear-cut, mature managed and unmanaged stands), using emergence traps on experimental CWD. We measured local CWD volumes and determined the availability of forests of a suitable age within the landscape. We tested parasitoid responses to stand type, CWD volume, abundance of known and probable hosts and longitude. Additionally, we tested whether parasitoids responded to the area of habitat of a suitable age within radii from 0.2 to 10 km. Stand type appeared in best-fit models for all common species, suggesting that wasps respond strongly to habitat at local scales. Longitude (largely climate) featured commonly, but CWD volume was never significant. Host abundance appeared in best-fit models for three of five common species, proving significant only for Bracon obscurator, the abundance of which correlated with that of Orthotomicus laricis at both trap and site levels. Rhimphoctona spp. also correlated significantly with its known host Tetropium castaneum at the trap level. B. obscurator responded to habitat area at scales of 0.6-1 km and Cosmophorus regius responded at radii greater than 7 km, while the larger species did not respond strongly to habitat area. The role of habitat area at greater scales thus varied greatly amongst species, but our data suggest that dispersal of these common early successional species may not be strongly restricted at the current scale of fragmentation of their boreal habitats.},
	keywords = {Dryocoetes, Hylastes, Hylurgops, Ips typographus, Orthotomicus, Pityogenes},
	isbn = {0029-8549},
	author = {Gibb, H. and Hilszczanski, J. and Hjalten, J. and Danell, K. and Ball, J. P. and Pettersson, R. B. and Alinvi, O.}
}
@article {11129,
	title = {Investigations on altitude related occurrence of bark beetles and pathogens in Ips typographus (L. 1758) (Coleoptera, Curculionidae) in the Gesaeuse national park area (Styria).},
	journal = {Mitteilungen der Deutschen Gesellschaft fuer Allgemeine und Angewandte Entomologie},
	volume = {18},
	year = {2012},
	month = {April},
	pages = {413-417},
	abstract = {Presence of bark beetles was investigated using infested trap logs from six locations in different altitudes. Log sections were cut and incubated in the laboratory; emerging beetles were removed and identified. Furthermore, pathogen occurrence was investigated in Ips typographus L. (Coleoptera, Curculionidae) from these six sites. In total eight bark beetle species were found; Ips typographus and Pityogenes chalcographus occurred in the logs from all locations, Ips amitinus only in higher elevation. Furthermore, fewer individuals emerged belonging to the species: Hvlurgops glabratus, Polygraphus poligraphus, Dryocoetes autographus, Pitvophthorus pityographus and Trypodendron lineatum. Six pathogen species were found in I. typographus (ItEPV, Gregarina typographi, Mattesia typographi, Chytridiopsis typographi, Nosema typographi, Unikaryon montanum). Infection rates varied in beetles from the different locations.},
	keywords = {Ips typographus},
	isbn = {0344-9084},
	author = {Gasperl, Hubert and Wegensteiner, Rudolf}
}
@article {10907,
	title = {Effect of weather on Ips typographus (Coleoptera Curculionidae) phenology, voltinism, and associated spruce mortality in the southeastern Alps},
	journal = {Environmental Entomology},
	volume = {38},
	number = {2},
	year = {2009},
	month = {April},
	pages = {307-316},
	abstract = {Summer drought associated with high temperatures recorded in the last few years has given rise to outbreaks of bark beetles developing in weakened host trees. The aim of this study was to investigate the possible weather effect on the biology of and damage caused by Ips typographus L. in the southeastern Alps. The study was carried out recording temperature (1962-2007), precipitation (1922-2007), and the damage caused by L typographus (1993-2007). In addition, data from pheromone-baited traps (1996-2005) provided information on the main periods of flight activity of I. typographus. From 1922 to 2007, precipitation during March-July has decreased [approximately equal]200 mm (-22\%), whereas since 1962-2007, mean temperatures during March-July increased [approximately equal]2[degree]C (+13\%). Damage caused by I. typographus was inversely correlated with March-July precipitation from the previous year but not correlated with temperature. Increases in spring temperature did not affect the development timing of the first generation, but only changed its onset. Earlier swarming of both over-wintering beetles and first-generation offspring ([approximately equal]20 d sooner over 10 yr), and the early start of the second generation permitted more complete development of the second brood. Voltinism in this species is discussed in relation to thermal and photoperiodic thresholds, indicating that the occurrence of a third generation is limited by the summer photoperiod rather than by temperature. In conclusion, results suggest that spring drought increases damage caused by L typographus in the following year, whereas warmer spring affects insect phenology.},
	keywords = {Ips typographus},
	isbn = {0046-225X},
	author = {Faccoli, Massimo}
}
@article {10909,
	title = {Breeding performance of the second generation in some bivoltine populations of Ips typographus (Coleoptera Curculionidae) in the south-eastern Alps},
	journal = {Journal of Pest Science},
	volume = {84},
	number = {1},
	year = {2011},
	month = {March},
	pages = {15-23},
	abstract = {The spruce bark beetle, Ips typographus, is one of the most extensively studied European forest pests. Gaps exist in the knowledge about second generation breeding performance in bivoltine populations. In this study, the breeding performance of the second generation was evaluated in three bivoltine populations of I. typographus in the SE Alps. Length of the maternal galleries (from 40.5 to 44.8 mm), population growth rate (PGR; from 0.7 to 3.6), and emerged adults per m2 (from 669 to 1,570 insects/m2) varied among populations and were negatively correlated with bark colonisation density. Pheromone traps set up in the three investigated forests differed in the number of trapped beetles, with mean captures ranging between 5,310 and 19,850 insects per trap. The populations giving the highest captures in the traps showed the lowest bark colonisation density (248 vs. 489 maternal galleries per m2) and the best breeding performance. The populations of parasitoids and predators corresponded to just 1[long dash]9 and 2[long dash]10\% of the emerging I. typographus adults, respectively, and phloem temperature never reached thresholds lethal to I. typographus. Interspecific competition was negligible, whereas intraspecific competition was found to be the main factor affecting the breeding performance of the second generation, although with different intensity according to the colonisation density. It is hypothesised that competition with the first generation and spring precipitation influence the number of suitable hosts available to the second generation.},
	keywords = {Ips typographus},
	isbn = {1612-4758},
	author = {Faccoli, Massimo and Bernardinelli, Iris}
}
@article {10911,
	title = {Conifer phenolic resistance markers are bark beetle antifeedant semiochemicals},
	journal = {Agricultural and Forest Entomology},
	volume = {9},
	number = {3},
	year = {2007},
	month = {August},
	pages = {237-245},
	abstract = {Phenols are important in conifer resistance to fungi associated with bark beetles and as markers for resistance to beetle mass-attacks. However, the mechanism of phenolic activity in conifer resistance to Ips typographus bark beetle remains unclear. By a new bioassay, we tested the effect on host acceptance and tunnelling of male and female L typographus in an artificial gallery (13 mm long) for 4 h (no-choice test). To the artificial diet, an aliquot of host (catechin, taxifolin, or resveratrol) or nonhost (E-conophthorin) compounds was added, singly tested at doses close to those of tree bark. Host acceptance and tunnelling was measured by the amount of diet removed by the insects. All tested chemicals decreased the tunnelling activity of L typographus, with an antifeedant effect stronger in males and increasing with dose. No mortality was recorded. The nonhost volatile spiroketal, E-conophthorin, had the highest antifeedant activity both in males and females. Among host compounds, effects and dose-response were weak in females. Both catechin and E-conophthorin gave a 50\% reduction of tunnelling at a concentration of 0.1\% for males, the pioneering (host selecting) sex in Ips. The threshold of activity for host compounds to males was at concentrations of 0.03-0.1\%, which corresponds to, or is less than, the concentrations reported from spruce host bark. The results allow us to support the hypothesis of a direct behavioural antifeedant mechanism for resistance from those phenols that are particularly active for the pioneering males during tree attack},
	keywords = {Ips typographus},
	isbn = {1461-9555},
	author = {Faccoli, Massimo and Schlyter, Fredrik}
}
@article {10885,
	title = {Ips typographus (L.) attack on patches of felled trees: "wind-felled" vs. cut trees and the risk of subsequent mortality},
	journal = {Forest Ecology and Management},
	volume = {255},
	number = {3-4},
	year = {2008},
	month = {March 20},
	pages = {1336-1341},
	type = {Article},
	abstract = {According to the Finnish Forest Insect and Fungal Damage Prevention Act, groups of 20 or more damaged conifers should be removed from forests. The main objective of this study was to evaluate the risks involved in leaving groups of 20 damaged spruce trees in managed forests. We also tested the effect of felling technique (natural with some remaining root connections vs. cutting) and the influence of recent forest disturbance history on Ips typographus colonization, breeding success and consequential damage to living trees. We felled groups of 20 spruce trees in 16 stands in November 2003. Half of the experimental stands were situated in southern Finland, which were damaged by autumn storms in 2001. The other half of the experimental stands was in eastern Finland, which was not affected by the storms. In this study, subsequent tree mortality occurred in only two (both in the southern study area) of the 16 experimental stands. Neither the experimental area nor the felling treatment significantly affected tree mortality. The number of colonized felled spruce trees and the densities of egg galleries in felled trees were significantly higher in the southern study area. This result indicates that population levels in the southern area were higher than in the eastern area-probably as a consequence of the autumn storms in 2001. Interestingly, there was also a significant interaction between the felling treatment and the study area, explaining the density of egg galleries in felled spruce trees. The results indicate that the population density of I. typographus affects the colonization process of felled trees, as the response to the felling treatment differed between study areas. Although there were differences in egg gallery densities, no significant differences in offspring production were found either between areas or between felling treatments.},
	keywords = {Ips typographus},
	isbn = {0378-1127},
	author = {Eriksson, Mikka and Neuvonen, Seppo and Roininen, Heikki}
}
@article {10884,
	title = {Retention of wind-felled trees and the risk of consequential tree mortality by the European spruce bark beetle Ips typographus in Finland},
	journal = {Scandinavian Journal of Forest Research},
	volume = {22},
	number = {6},
	year = {2007},
	month = {2007},
	pages = {516-523},
	abstract = {Autumn storms felled about 7 million m3 of forest in southern Finland in 2001. Windthrow area and timber characteristics, as well as numbers of standing spruce trees attacked and killed by Ips typographus, were recorded in 61 Norway spruce [Picea abies (L.) Karst.]-dominated windthrow areas. Generalized linear models were used to identify significant variables predicting the risk for consequential tree mortality by I. typographus. None of the windthrow areas with fewer than 20 wind-felled spruce trees (WFS) (n=28) and only half of the areas with 20 or more WFS (n=33) harboured trees killed by I. typographus during the years 2003-2005. The quantity and diameter of WFS and the basal area of recently dead standing spruce trees correlated positively with the risk of tree deaths. This study indicates that in Finland, at endemic I. typographus population levels, it is safe to leave fewer than 20 WFS in managed forests. Retention of even larger quantities of trees does not seem to evoke significant numbers of consequential tree deaths by I. typographus in managed forests. However, in stands where the natural mortality of spruce trees is high, the risks of consequential tree deaths after wind disturbance will also be higher.},
	keywords = {Ips typographus},
	isbn = {0282-7581},
	author = {Eriksson, Miikka and Neuvonen, Seppo and Roininen, Heikki}
}
@article {10877,
	title = {A host monoterpene influences Ips typographus (Coleoptera: Curculionidae, Scolytinae) responses to its aggregation pheromone},
	journal = {Agricultural and Forest Entomology},
	volume = {9},
	number = {2},
	year = {2007},
	month = {May},
	pages = {135-140},
	abstract = {1 Host tree terpenes can influence attraction of conifer-infesting bark beetles to their aggregation pheromones, and both synergistic and inhibitory effects have been reported. 2 We tested a gradient of ratios of (-)-a-pinene, the predominant monoterpene in Norway spruce, to the pheromone of Ips typographus, a major pest of Norway spruce. 3 Attraction of I. typographus increased as the release rate of (-)-a-pinene increased. The two highest (-)-a-pinene : pheromone ratios (526 : 1 and 2595 : 1) attracted twice as many I. typographus as pheromone alone, whereas low to intermediate ratios (56 : 1, 274 : 1) did not differ from pheromone alone. 4 Our results are in agreement with a proposed model, which suggests that bark beetles display unique response profiles to host terpenes depending on the physiological condition of the host trees that they typically colonize. Ips typographus, which is an aggressive species capable of colonizing and killing healthy trees, showed an increased attraction to monoterpene : pheromone ratios, and this may be high enough to inhibit attraction of less aggressive beetle species typically colonizing dead, dying or stressed trees. 5 Attraction of associates of I. typographus was also modified by (-)-a-pinene. Ips duplicatus, a competitor of I. typographus, showed increased attraction to the pheromone of I. typographus across all concentrations of (-)-a-pinene},
	keywords = {Ips typographus},
	isbn = {1461-9555},
	author = {Erbilgin, Nadir and Krokene, Pal and Kvamme, Torstein and Christiansen, Erik}
}
@article {10745,
	title = {A simple method for the detection of imaginal diapause in beetles},
	journal = {Journal of Applied Entomology},
	volume = {131},
	number = {3},
	year = {2007},
	month = {April},
	pages = {221-223},
	abstract = {Investigations on Ips typographus and Leptinotarsa decemlineata revealed that the activity of mitochondrial enzymes in the flight muscles provides a reliable criterion for the discrimination of diapausing and non-diapausing adults. Enzyme activity is conveniently detected in situ with commercially available tetrazolium salts. Staining intensity is correlated with the flight ability and often also with reproduction.},
	keywords = {Ips typographus},
	isbn = {0931-2048},
	author = {Dolezal, P. and Sehnal, F.}
}
@article {10744,
	title = {Effects of photoperiod and temperature on the development and diapause of the bark beetle Ips typographus},
	journal = {Journal of Applied Entomology},
	volume = {131},
	number = {3},
	year = {2007},
	month = {April},
	pages = {165-173},
	abstract = {Diapause was induced in a Central European population of Ips typographus grown at 20 [degree]C when the day length decreased below 16 h (50\% diapause incidence occurred in the 14.7:9.3 h L:D (light: dark) regime). The nondiapausing adults fed on days 2-6 and 10-14 after the ecdysis and swarmed after the second feeding bout with chorionated eggs in the ovaries and sperm in the spermiducts. Neither gonads nor the flight muscles matured and no swarming occurred in the diapausing adults. The development from egg to adult took about 34 days in both 18:6 h (no diapause) and 12:12 h L: D (diapause) regimes, but it was extended by up to 30\% without diapause induction when only larvae or pupae were exposed to L: D 12:12 h. Diapause was induced in insects reared at L: D 12:12 h through the last larval and the pupal instars and/or in the adult stage. Temperature 23 [degree]C prevented diapause induction at L:D 12:12 h but diapause occurred at L: D 14:10 h associated with 26:6 [degree]C thermoperiod. The effect of thermoperiods on the developmental rate requires further research. Exposure of the non-diapausing adults to 5 [degree]C for several days blocked feeding and evoked a diapause- like state, whereas diapausing adults fed and their gonads slowly developed at this temperature. Diapausing adults exposed in forest to low night temperatures and transferred in October to 20 [degree]C readily reproduced at 18:6, but not 12:12 h L: D photoperiods. After 2-months at 5 [degree]C and darkness, they became insensitive to the photoperiod, matured and most of them also swarmed at 20 [degree]C in the 12:12 h L:D regime. In a Scandinavian population, diapause occurred at 18:6 h L:D and was terminated either by exposure to 5 [degree]C or by very long photoperiod (L: D 20:4 h) combined with high temperature (23 [degree]C)},
	keywords = {Ips typographus},
	isbn = {0931-2048},
	author = {Dolezal, P. and Sehnal, F.}
}
@article {10591,
	title = {Research on the proper usage of the pheromone trap method monitoring and mass trapping of Ips typographus L. and Pityogenes chalcographus L. in the federation of Bosnia and Herzegovina},
	journal = {Forstschutz Aktuell},
	volume = {44},
	year = {2008},
	month = {November},
	pages = {10-11},
	type = {Article; Meeting paper},
	abstract = {The purpose of this paper is to determine the number of installed synthetic pheromone baited traps for monitoring and mass trapping of 1ps typographus and Pityogenes chalcographus. the types of traps and pheromone dispensers and the propriety of used method on the site (trap position, trap distance of the nearest healthy spruce tree, trap height, etc.) are examined. The number of controlled traps was 1116; the number of those completely correctly placed traps was 223, that is 20 percent.},
	keywords = {Ips typographus, Pityogenes chalcographus},
	isbn = {1815-5111},
	author = {Dautbasic, Mirza and Trestic, Tarik and Mujezinovic, Osman and Bajric, Muhamed}
}
@article {9618,
	title = {Antagonists of the spruce bark beetle Ips typographus L. (Coleoptera: Scolytidae) of German and Georgian populations},
	journal = {IOBC-WPRS Bulletin},
	volume = {31},
	year = {2008},
	month = {2008},
	pages = {245-250},
	type = {Article; Meeting paper},
	keywords = {Ips typographus},
	isbn = {1027-3115},
	author = {Burjanadze, Medea and Moser, John C. and Zimmermann, Gisbert and Kleespies, Regina G.}
}
@article {9453,
	title = {Occurrence of the European spruce bark beetle Ips typographus (L.) and six-toothed spruce bark beetle Pityogenes chalcographus (L.) in spruce stands damaged by wind in the Swietokrzyskie Mountains},
	journal = {Lesne Prace Badawcze},
	volume = {72},
	number = {1},
	year = {2011},
	month = {2011},
	pages = {31-36},
	abstract = {The aim of this study was to assess the density and sex ratio of the Ips typographus population and associated species in managed spruce stands growing in the territory of the Zagnansk Forest District. In June and July of 2008 and 2009, colonisation of 30 windfalls was assessed using entomological section-based analysis. During the research period, I. typographus infested all investigated trees colonising their entire lengths from top to bottom except for the stem section covering height increments from the previous and current years (100\% frequency in stem sections). Stem infestation density indicators in the years 2008-2009 were 466 and 455 maternal galleries m-2, respectively. The sex ratio of the I. typographus population points to an increase in this pest species, since there were twice as many females as males in the population (67 - 67.5\%). The uniform distribution of egg galleries on the stems and the lack of a relationship between the diameter of stem sections and their infestation density (r = -0.0447, P = 0.3126) indicate that I. typographus can infest a wide range of thicknesses of breeding material giving it a broad habitat tolerance. Pityogenes chalcographus (L.) primarily accompanied I. typographus, and it exhibited a similar average infestation density in both seasons, ranging from 68 to 71 egg galleries m-2 on those spruce trees that were examined. A positive correlation between the density of I. typographus maternal galleries and the density of P. chalcographus egg galleries (r = 0.3766, P=0.0001) indicates an overlap between the ecological niches of these bark beetle species. These results may suggest that under favourable weather conditions there is a genuine risk of bark beetle outbreaks in the territory of the Zagnansk Forest District},
	keywords = {Ips typographus},
	isbn = {1732-9442},
	author = {Borkowski, Andrzej}
}
@article {9454,
	title = {Statistical evaluation of Ips typographus population density: a useful tool in protected areas and conservation-oriented forestry},
	journal = {Biodiversity and Conservation},
	volume = {20},
	number = {13},
	year = {2011},
	month = {Dec},
	pages = {2933-2951},
	abstract = {Ips typographus (Col., Curculionidae, Scolytinae) occurring on Picea abies stems is a species characterised by large fluctuations in population numbers and causing frequent outbreaks. In protected areas, I. typographus is regarded as a sensitive bioindicator responsive to changes in forest health and vitality. In conservation-oriented forestry, attention is being paid to the ecological value of I. typographus beetles as ecosystem engineers and keystone species, driving forest natural regeneration and conversion. Despite many publications devoted to I. typographus, no accurate method for estimating the population density of this species has been developed. The objective of this study was to develop a statistical method for estimating I. typographus population density that enables calculation of estimation errors. The proposed method consists of two parts: tree-level analyses and stand-level analyses. Part one allows calculation of the total density of I. typographus infestation of each of P. abies selected stem (after selecting sample windfalls), part two allows estimation of the mean total infestation density of the stem in the area investigated. Linear regression functions were applied to part one and survey sampling to part two. The method is only marginally invasive because it involves debarking of one 0.5 m-long stem section on maximum 50 P. abies windfalls (trap trees can optionally be used). The developed method was employed to assess I. typographus population density in the AewiA(TM)tokrzyskie Mountains in Central Poland in an area of ca. 4,000 ha. In 2010, in the area investigated, the mean total I. typographus infestation density of the P. abies stem was 440.6 maternal galleries/m2 (from 358.7 to 522.6 maternal galleries/m2 with [alpha] = 0.05; the relative error of estimation was 18.6\%). The examined I. typographus population was in a progradation phase. The proposed method can be used in nature reserves, national parks and managed forests, mainly for scientific purposes.},
	keywords = {Ips typographus},
	isbn = {0960-3115},
	author = {Borkowski, Andrzej and Podlaski, Rafal}
}
@article {9416,
	title = {Effect of (+)-limonene and 1-methoxy-2-propanol on Ips typographus response to pheromone blends},
	journal = {Journal of Forestry Research (Harbin)},
	volume = {20},
	number = {1},
	year = {2009},
	month = {February},
	pages = {37-44},
	abstract = {We compared two different strategies to increase the catches of Ips typographus (L.), particularly males, in pheromone-baited traps, The first of these strategies, the barrier approach, used alternating pheromone blends, targeting males and females respectively, in closely-spaced traps forming a barrier around forest stands. The second strategy, the single trap approach, used widely-spaced traps that were all baited with the same lure and intended to trap the highest possible numbers of males without compromising trapping of females. In the blend used for the barrier traps targeting primarily males, with a lower percentage of (4S)-cis-verbenol (cV), the ( )-[alpha]-pinene was replaced step wise with (+)-limonene at rates of 0\%, 1\%, 10\%, 35\%, 60\% and 90\%. This replacement had no significant effect oil the numbers of responding L. typographus males, but there was a slight effect oil the percentage of males caught. In the attractant blend for the barrier traps targeting females, with a higher percentage of cV, the 2-methyl-3-buten-2-ol (MB) was replaced with 1-methoxy-2-propanol (MP) in a similar fashion as for the male-specific blend. The replacement did not significantly affect the catch of females. Thus, it is Possible to use the MP in the blend with eV and ipsdienol without significant change in catch efficacy. In the blends for single traps, the ( )-[alpha]-pinene was replaced with (+)-limonene and MB with MP. The replacement of ( )-[alpha]-pinene had only a slight effect oil the percentage of males, but the results suggest that replacing MB with MP in the blend will not significantly reduce trapping efficacy.},
	keywords = {Ips typographus},
	isbn = {1007-662X},
	author = {Blazenec, Miroslav and Jakus, Rastislav}
}
@article {9362,
	title = {Evaluation of scanning electron microscopy to study nematodes associated with insects},
	journal = {Redia},
	volume = {91},
	year = {2008},
	month = {2008},
	pages = {185-187},
	type = {Article; Meeting paper},
	abstract = {Bark and longhorn beetles were collected and screened for the presence of nematodes. Scanning electron microscopy (SEM) was necessary since most adult insects, isolated from traps and recently felled trees, were dead. The insects, suitably preserved and treated for SEM observations, presented juvenile forms of nematodes packed in a cocoon-like structure covered with a protective sticky substance, which attaches the nematodes to the insect{\textquoteright}s body. Most nematodes were found beneath the elytra but also under the wings, around the abdominal spiracles and on the abdomen.},
	keywords = {Hylurgops palliatus, Hylurgus ligniperda, Ips typographus, Orthotomicus erosus, Xyleborus saxesenii, Xylosandrus crassiusculus, Xyloterus lineatus},
	isbn = {0370-4327},
	author = {Benvenuti, Claudia and Baccetti, Baccio}
}
@article {9161,
	title = {Online-modelling of the development and phenology of Ips typographus using the model PHENIPS and daily weather data and forecasts provided by the DWD},
	journal = {Mitteilungen der Deutschen Gesellschaft fuer Allgemeine und Angewandte Entomologie},
	volume = {18},
	year = {2012},
	month = {April},
	pages = {397-400},
	abstract = {The temperature-dependent phenology and brood development of Ips typographus (L.) (Coleoptera, Curculionidae) can be simulated by means of the model PHENIPS (Baier\&al., 2007). PHENIPS air temperature and solar radiation as basic data input for modelling of the beetles{\textquoteright} phenology and seasonal development. In Saxony, the applicability of the model was tested using detailed observations of brood development of I. typographus in trap trees, recordings of phloem temperatures and data from monitoring of the swarming activity by means of pheromone traps. Based on weather recordings of several forest meteorological stations in Saxony, an application for modelling and visualisation of the development of I. typographus by automatically updated diagrams on the internet was established. Since April 2010, daily weather recordings and forecasts from selected agrometeorological stations, provided by the DWD (Deutscher Wetterdienst), are additionally used for daily updated modelling of the beetles{\textquoteright} development. Furthermore, the station-based modelling results in Saxony are regionalised using specific biogeoclimatic regions for spatial-temporal visualisation of modelling results on the internet. The developed tools for real-time monitoring of the development of I. typographus in the field can be used as an early warning system and provide essential information for the specific users concerning priority decisions, scheduling and timely realization of direct control and preventive measures.},
	keywords = {Ips typographus},
	isbn = {0344-9084},
	author = {Baier, Peter and Pennerstorfer, Josef and Otto, Lutz-Florian and Schopf, Axel}
}
@article {9162,
	title = {PHENIPS - A comprehensive phenology model of Ips typographus (L.) (Col., Scolytinae) as a tool for hazard rating of bark beetle infestation},
	journal = {Forest Ecology and Management},
	volume = {249},
	number = {3},
	year = {2007},
	month = {September 30},
	pages = {171-186},
	abstract = {We developed the model PHENIPS for spatial and temporal simulation of the seasonal development of Ips typographus at the Kalkalpen National Park in Austria. The model is based on a digital elevation model used for interpolation of temperature and solar radiation to calculate the microclimatic conditions (bark temperature) for the beetles{\textquoteright} development. Additionally, the beetles{\textquoteright} phenology at Kalkalpen National Park was monitored along with air and bark temperature measurements. The onset of host tree infestation in spring was estimated using a lower threshold of 16.5 [degree]C for flight activity and a mean thermal sum of 140 degree-days (dd) from beginning of April 1st onward. Rate of brood development was calculated from accumulated degree-days of hourly temperature data using upper and lower temperature thresholds of 38.9 and 8.3 [degree]C, respectively, and a nonlinear function for calculating effective thermal sums. Re-emergence of parental beetles occurred at a time when 49.7\% of the thermal sum for total development (557 dd) was reached. The model includes the discontinuance of the beetle{\textquoteright}s reproductive activity at a day length 14.5 h. The rate of successful hibernation of established broods is predicted by assessing the developmental stage of initiated generations at the beginning of the cold period. For validation we compared the timing of phenological events in the field with predicted events using both, hourly recorded data at trap trees in the terrain and generated daily topoclimatic data. Using topoclimatic data, the onset of infestation was predicted with a mean absolute error of 1.3 days. The observed onset of emergence of filial beetles in the field was estimated with a mean error of 39 dd. Our PHENIPS explicitly considers the strong effects of regional topography and stand conditions on local air and bark temperature and can be used for precise monitoring of the actual state of bark beetle development at the specific stand/tree level. Using topoclimatic data, PHENIPS simulates the maximum number of generations which is necessary to assess the potential impact of bark beetle outbreaks at regional scale. Further applications of PHENIPS for site-specific hazard rating of bark beetle infestation are discussed. [copyright] 2007 Elsevier B.V. All rights reserved},
	keywords = {Ips typographus},
	isbn = {0378-1127},
	author = {Baier, Peter and Pennerstorfer, Josef and Schopf, Axel}
}
@article {8930,
	title = {Defoliation levels of oriental spruce by Ips typographus (L.) in relation to elevation and exposure},
	journal = {Journal of Environmental Biology},
	volume = {29},
	number = {2},
	year = {2008},
	month = {March},
	pages = {223-226},
	type = {Article},
	abstract = {A study concerning the effects of elevation and exposure of the spruce forests on defoliation levels of oriental spruce (Picea orientalis (L.) Link.) by Ips typographus L. was carried out during 2005 and 2006 in Artvin-Hatila National Park, Turkey Nine spruce stands were selected at 3 zones of elevations (1000-1350 m, 1350-1700 m and 1700-2000 m) and at different aspects to assess the role of elevation and exposure in the crown defoliation level and body length of beetles. Influence of bark thickness and trunk diameter at 1.3 m on the damage caused by the pest was investigated as well. The results of the study were as follows: (1) The mean defoliation level was highest at 1700-2000 m following by 1350-1700 m and 1000-1350 m. (2) The highest defoliation levels occurred on southern slopes following by eastern and northern slopes at 1700-2000m. (3) No statistical differences were found in the mean bark thickness between tree defoliation levels 1, 2, 3 and 4.(4) Mean trunk diameters of dead trees (level4) were significantly greater than those with defoliation levels 0, 1 and 2. (5) Mean body length of L typographus at upper zones was significantly higher than those at middle and lower zones},
	keywords = {Ips typographus},
	isbn = {0254-8704},
	author = {Akkuzu, E. and Guner, S.}
}
@article {6000,
	title = {Host resistance elicited by methyl jasmonate reduces emission of aggregation pheromones by the spruce bark beetle, Ips typographus},
	journal = {Oecologia (Berlin)},
	volume = {167},
	number = {3},
	year = {2011},
	month = {Nov},
	pages = {691-699},
	abstract = {We treated Norway spruce (Picea abies) stems with methyl jasmonate (MeJA) to determine possible quantitative and qualitative effects of induced tree defenses on pheromone emission by the spruce bark beetle Ips typographus. We measured the amounts of 2-methyl-3-buten-2-ol and (S)-cis-verbenol, the two main components of the beetle{\textquoteright}s aggregation pheromone, released from beetle entrance holes, along with phloem terpene content and beetle performance in MeJA-treated and untreated Norway spruce logs. As expected, phloem terpene levels were higher and beetle tunnel length was shorter (an indication of poor performance) in MeJA-treated logs relative to untreated logs. Parallel to the higher phloem terpene content and poorer beetle performance, beetles in MeJA-treated logs released significantly less 2-methyl-3-buten-2-ol and (S)-cis-verbenol, and the ratio between the two pheromone components was significantly altered. These results suggest that host resistance elicited by MeJA application reduces pheromone emission by I. typographus and alters the critical ratio between the two main pheromone components needed to elicit aggregation. The results also provide a mechanistic explanation for the reduced performance and attractivity observed in earlier studies when bark beetles colonize trees with elicited host defenses, and extend our understanding of the ecological functions of conifer resistance against bark beetles.},
	keywords = {Ips typographus},
	isbn = {0029-8549},
	author = {Zhao, Tao and Borg-Karlson, Anna-Karin and Erbilgin, Nadir and Krokene, Paal}
}
@article {5761,
	title = {Modelling spruce bark beetle infestation probability},
	journal = {Baltic Forestry},
	volume = {15},
	number = {1},
	year = {2009},
	month = {2009},
	pages = {23-27},
	abstract = {Spruce bark beetle (Ips typographus L.) risk model, based on pure Norway spruce (Picea abies Karst.) stand characteristics in experimental and control plots was developed using classification and regression tree statistical technique under endemic pest population density. The most significant variable in spruce bark beetle infestation risk model was spruce basal area. Model, good enough for forest management practices, rate spruce stands to: a) stands of low bark beetle risk (probability of infestation p=20\%) - basal area of spruce less than 17.8 m2/ha; b) stands of moderate bark beetle risk (p=55\%) - spruce basal area greater than 17.8 but less then 46.9 m2/ha; c) stands of high bark beetle risk (p=83\%) - spruce basal area greater than 46.9 m2/ha. Further model clarification need research under epidemic spruce bark beetle condition levels.},
	keywords = {Ips typographus},
	isbn = {1392-1355},
	author = {Zolubas, Paulius and Negron, Jose and Munson, A. Steven}
}
@article {5654,
	title = {Declining Bark Beetle Densities (Ips typographus, Coleoptera: Scolytinae) from Infested Norway Spruce Stands and Possible Implications for Management},
	journal = {Psyche (Cambridge)},
	volume = {2012},
	year = {2012},
	month = {2012},
	pages = {7pp.},
	abstract = {The eight-toothed spruce bark beetle (Ips typographus) is the most serious insect pest in Central European forests. During the past two decades, extreme meteorological events and subsequent beetle infestations have killed millions of cubic meters of standing spruce trees. Not all the infested stands could be cleared in time, and priorities inmanagement had to be set. Natural orman-made buffer zones of about 500 meters in width are frequently defined to separate differently managed stands in Central Europe. While the buffer zones seemto be effective inmost of the cases, their impact has not been studied in detail. Beetle densities were therefore assessed in three case studies using pheromone traps along transects, leading from infested stands into spruce-free buffer zones. The results of the trap catches allow an estimation of the buffer zone influence on densities and the dispersal of Ips typographus. Beetle densities were found to decrease rapidly with increasing distance from the infested spruce stands. The trap catches were below high-risk thresholds within a few hundred meters of the infested stands. The decrease in catches was more pronounced in open land and in an urban area than in a broadleaf stand. Designed bu?er zones of 500m width without spruce can therefore very probably help to reduce densities of spreading beetles.},
	keywords = {Ips typographus},
	isbn = {0033-2615; 1687-7438},
	url = {http://downloads.hindawi.com/journals/psyche/2012/321084.pdf},
	author = {Angst, Alexander and Rueegg, Regula and Forster, Beat}
}
@article {5502,
	title = {Ips typographus (L.) and Thanasimus formicarius (L.) populations influenced by aspect and slope position in Artvin-Hatila valley national park, Turkey},
	journal = {African Journal of Biotechnology},
	volume = {8},
	number = {5},
	year = {2009},
	month = {6 March},
	pages = {877-892},
	abstract = {This study investigated the effects of aspect (north and south) and slope position (top slope: 1100 - 1700 m and bottom slope: 1700 - 2200 m) on Ips typographus (L.) and its major predator Thanasimus formicarius (L.) populations and body length and weight of the pest I. typographus (L.) in oriental spruce (Picea orientalis (L.) Link.), dominated stands in Artvin-Hatila Valley National Park, Turkey for two years (2006- 2007). A total of 120 pheromone traps were used to assess the population levels of both insect species. The results of the study were as follows: 1.) I. typographus (L.) population on each aspect was significantly higher at the top slope stands than the other sites whereas T. formicarius (L.) population was higher at the bottom slope stands on the north-facing site. 2.) There was no correlation between the number of T. formicarius (L.) and I. typographus (L.) caught by pheromone traps. 3.) Body length and weight of I. typographus (L.) were significantly higher on south aspect and at the top slope on each aspect.},
	keywords = {Ips typographus},
	isbn = {1684-5315},
	url = {http://www.academicjournals.org/AJB/contents/2009cont/6Mar.htm},
	author = {Akkuzu, Erol and Sariyildiz, Temel and Kucuk, Mehmet and Duman, Ahmet}
}
