Flight ability and reproductive development in newly‐emerged pine weevil Hylobius abietis and the potential effects of climate change

• 1 Adult pine weevils Hylobius abietis emerge from conifer root‐stumps, on which larvae develop, over an extended period during summer and autumn. Newly‐emerged weevils were tested for their ability to fly and assessed for wing muscle and reproductive development. In addition, the effect of summer–autumn maturation feeding on reproductive development was assessed in field bioassays.
• 2 There was considerable variation in development between newly‐emerged weevils that was related to the timing of emergence. The first weevils, emerging in early July, weighed less than later‐emerging ones, had undeveloped flight muscles and did not fly. Over the emergence period, wing muscle size and flight ability increased markedly, with 50–60% flying by mid‐September. Differences between emerging adults are likely to have been affected by temporal changes in the quality of the bark on which the larvae feed.
• 3 Reproductive development lagged behind that of wing muscles but, in early August, there was a rapid increase in the proportion of weevils with immature eggs and a corresponding increase in oocyte size. However, although wing muscles were fully formed in later‐emerging weevils, immature eggs were only approximately 10% of the volume of mature eggs.
• 4 In field bioassays of summer–autumn maturation feeding, eggs continued to develop and some weevils laid mature eggs. Feeding and development during the pre‐overwinter period is likely to influence winter survival and also dispersal and reproduction in the following spring.
• 5 The potential effects of climate change on the weevil life cycle are briefly discussed. Weevils are likely to benefit from the higher temperatures and later autumns predicted under climate change, resulting in an increase in damage to transplants.

     

Reproductive seasonality in tropical satyrine butterflies: strategies for the dry season

Abstract.

• 1 In tropical savanna environments rainfall is often very seasonal, so that much of the year is characterized by a long and unpredictable dry season. Because the timing and availability of rain exerts a major influence on plant growth and production, many species during the dry period exhibit dramatic reduction in leaf quality. Accordingly, and kind of behaviour shown by phytophagous insects that synchronizes larval feeding with food availability will be adaptive.
• 2 The reproductive status of three Mycalesis butterflies was monitored over a 2-year period (1989–90) in north-eastern Queensland, Australia, at a lowland site (Cardwell, 18°16's, 146°02′E) which experiences a pronounced dry season. Females of these species and of five other satyrines (Ypthima, Hypocysta spp.) were also examined less intensively during the dry season in areas throughout northern and central Queensland, north of the tropic of Capricorn.
• 3 These relatively sedentary butterflies exhibit three different strategies for dealing with the unpredictable dry period and associated deterioration of larval food plants (grass). First, five species appear to breed continuously, though for most reproductive activity (mature egg number) declines markedly in the late dry season. Two of these (Hypocysta irius, H.metirius) are restricted to less seasonal and more favourable (wetter) areas but the three others (Ypthima arctous, H.adiante, H.pseudirius) occur widely in the relatively dry savanna, where they may specialize on grass in moister microenvironments. Second, two species (M.terminus, M.sirius) live in predictably moist habitats which are buffered from climatic extremes; they breed for much of the season but reproductive activity declines as the dry season progresses and may cease late in the season. Third, one species (M.perseus) is more opportunistic, breeding for only a limited interval during the favourable (wet) periods; during the long dry season adults contract to moist refugia and remain in reproductive diapause.
• 4 Spending the late dry season as an adult, either in diapause or with mature eggs, may improve the capacity to utilize new growth of grasses at the start of the favourable season, thereby enhancing population growth during good times. It may also provide additional flexibility to counter the temporal uncertainty of the dry season.
• 5 The strategy of residing in more equitable habitats or specializing on predictable foods may be the most restrictive in terms of distribution.

     

The effect of cold temperature exposure and long-day photoperiod on the termination of the reproductive diapause of newly emerged female Pissodes strobi (Coleoptera: Curculionidae)

Abstract

• 1 There is confusion in the literature concerning a possible reproductive diapause in the adult white pine weevil Pissodes strobi.
• 2 We evaluated the effects of temperature, photoperiod, feeding substrate and mating status on the sexual maturation and oviposition of female white pine weevils.
• 3 Less than 30% of female P. strobi became sexually mature and laid eggs without experiencing dormancy under a temperature regime of 2 °C for 4 weeks.
• 4 Among the females that experienced a cold temperature treatment after emergence, 80% laid eggs after dormancy when exposed to a long‐day (LD 16 : 8 h) photoperiod and 17.6% laid eggs when exposed to a short‐day (LD 8 : 16 h) photoperiod.
• 5 Significantly more eggs were laid by all the females (with and without a cold treatment) when subjected to a long‐day photoperiod compared with a short‐day photoperiod.
• 6 A period of cold temperature followed by exposure to a long‐day photoperiod with warmer temperatures is required to break reproductive diapause and to obtain a good oviposition response in female P. strobi.
• 7 This study reveals the existence of much intraspecific variation in the response of the white pine weevil to temperature and photoperiod with respect to the induction and termination of reproductive diapause.

     

Phytoplankton community structure and environment in the Kenyan waters of Lake Victoria

• 1 Phytoplankton species composition, numerical abundance, spatial distribution and total biomass measured as chlorophyll a concentration were studied in relation to environmental factors in September 1994 (dry season) and March 1995 (rainy season), respectively, in the Kenyan waters of Lake Victoria; 103 species were recorded.
• 2 Blue‐green algae (Cyanophyceae) were most diverse, followed by diatoms (Bacillariophyceae), green algae (Chlorophyceae) and dinoflagellates (Dinophyceae).
• 3 Twinspan separated the phytoplankton communities in the Nyanza Gulf and those in the open lake during both seasons. During the dry season, the Nyanza Gulf was strongly dominated by blue‐greens, while diatoms dominated in the open lake. During the rainy season, blue‐greens remained dominant in the Nyanza Gulf although the number of species found was lower than during the dry season; in the open lake, blue‐greens replaced diatoms as the dominant group and there were more species than in the dry season.
• 4 Canonical correspondence analysis indicated that the phytoplankton species distribution was significantly correlated with turbidity during the dry season and with SiO₂ during the rainy season. Chlorophyll a concentrations ranging from 2.0 to 71.5 mg m^‐3 in the dry season and 2.0–17.2 mg m^‐3 in the rainy season confirm earlier reports of increasing phytoplankton biomass in Lake Victoria since the 1960s.

     

Potential for host range expansion in Ceratitis capitata flies: impact of proximity of adult food to egg-laying sites

Abstract.

• 1 In field cage and field tests, female Mediterranean fruit flies, Ceratitis capitata (Wiedemann), in trees alighted in significantly greater numbers upon sticky-coated (non-odour-emitting) kumquats, Fortunella japonica, that were in the vicinity of odorous natural proteinaceous food (bird faeces) or synthetic food odour than on similar kumquats distant from bird faeces or synthetic food odour.
• 2 In field cage tests, oviposition in non-sticky kumquats nearby bird faeces was significantly greater than in non-sticky kumquats distant from bird faeces.
• 3 In field tests, medflies laid significantly more eggs in host kumquat and non-host hawthorn, Crataegus mollis, fruit adjacent to bird faeces and synthetic food odour than in fruit of these types distant from food-type stimuli.
• 4 These findings suggest that odour of natural food of medflies could lure flies to plants whose fruit emit little or no attractive odour and are not permanent hosts but which are nonetheless susceptible to egg-laying and larval development, resulting in temporary expansion of host range.

     

Fish as vectors in the dispersal of Bythotrephes cederstroemi: diapausing eggs survive passage through the gut

• 1 Bythotrephes cederstroemi (Crustacea: Onychopoda: Cercopagidae) is an introduced invertebrate predator currently spreading through the Laurentian Great Lakes region of North America. We examined a previously unsuspected way in which B. cederstroemi may be dispersed by fish by their consumption of diapausing eggs.
• 2 Ninety‐four percentage of the mature B. cederstroemi diapausing eggs consumed by fish were egested apparently intact. This proportion is considerably above previous estimates for the ephippial eggs of Daphnia. The hatching success of diapausing eggs was compared among four categories: (a) eggs released naturally by B. cederstroemi (control, 73% hatched) (b) eggs released during ‘stressful confinement’ (46% hatched) (c) eggs dissected from dead females (13% hatched) and (d) eggs recovered from faecal pellets following consumption by fish (viable gut passage experiment, 41% hatched).
• 3 Samples of small fish and B. cederstroemi were collected simultaneously. Examination of gut contents revealed that fish contained B. cederstroemi diapausing eggs and that B. cederstroemi bearing resting eggs were consumed selectively over those without eggs. Moreover, fish selected B. cederstroemi bearing mature rather than immature diapausing eggs.
• 4 The fact that diapausing eggs survive gut passage is important for the dispersal of B. cederstroemi. Fish often move between the pelagic and littoral zones of lakes and may thus disperse diapausing eggs widely. Fish may also move between lakes connected by river systems and can be caught and passively dispersed by anglers or piscivorous birds. Our results demonstrate the potential for fish to act as vectors in the spread of B. cederstroemi.

     

Effects of predation on clutch size and egg dispersion in the codling moth Laspeyresia pomonella

ABSTRACT.

• 1 The effects of predation on clutch size and egg dispersion in the codling moth Laspeyresia pomonella (L.) were experimentally studied in an orchard by recording survival of eggs glued onto different substrates.
• 2 Egg mortality due to sucking insects was readily distinguishable from that due to chewing insects.
• 3 In both the field and laboratory, females preferred to deposit eggs singly on the uppersides of leaves.
• 4 Eggs on the uppersides of leaves and on fruit survived significantly better than did those on the undersides of leaves or on twigs.
• 5 Egg losses were highest during the early part of the flight season.
• 6 The smallest (one egg) and largest (nine eggs) clutches, associated with one egg-bearing leaf per twig, both suffered the lowest rates of predation. Factors selecting against oviposition on fruits and production of large clutch sizes are presented and discussed.

     

Spotted wing drosophila (Drosophila suzukii) utilization and dispersal from the wild host Asian bush honeysuckle (Lonicera spp.)

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Seasonal shifts in host usage in Uroleucon gravicorne (Homoptera: Aphididae) and implications for the evolution of host alternation in aphids

ABSTRACT.

• 1 Uroleucon gravicome (Patch) feeds on annual Erigeron species and on perennial Solidago species.
• 2 To test whether Solidago and Erigeron are analogous to winter and summer hosts of typical host-alternating aphids, reproductive performance, host preferences, and host associations were measured for E.strigosus, S.juncea and S.nemoralis during spring, summer and autumn.
• 3 Caged individuals can reproduce on both genera throughout the season, though colonies are rare on Solidago during summer.
• 4 Developmental rate, adult weight, and fecundity decline between May and August on all hosts; however, the drop is least on E.strigosus, intermediate on S.nemoralis, and greatest on S.juncea.
• 5 Throughout the season, reproductive performance is at least as great on Erigeron as on Solidago, the difference being least in spring.
• 6 Soluble nitrogen content shows the same seasonal trends as reproductive performance, declining in all hosts, but declining least in E.strigosus.
• 7 Preference tests and field records show that U.gravicorne moves from Solidago to Erigeron when the first alatae mature in late spring, feeds on Erigeron during the summer, and, in late summer, returns to Solidago where overwintering eggs are laid.
• 8 Solidago is not nutritionally superior during spring or autumn; its use during those seasons may result from the need for good oviposition sites.

     

Life stages of the non-native Ommatoiulus moreleti (Lucas, 1860) (Julida,Julidae) in Australian small grain systems

1. The Portuguese millipede, Ommatoiulus moreleti (Lucas, 1860), is increasingly a pest of grains crops in Australian agricultural ecosystems. With the rapid uptake of minimum-tillage practices, habitat quality has been enhanced for several species of soil dwelling invertebrates, in particular O. moreleti.
2. To understand the population dynamics of O. moreleti in Australian grains crops, populations were sampled at multiple sites for more than 2 years using pitfall traps and cardboard roll traps. Specimens were dissected to investigate reproductive status and developmental stage.
3. Millipede trapping rates varied between sites and across the year, and tended to be lower when soil water content (m³/m³) was high. Both sexes were active year round, however females were relatively more abundant when ground temperatures were higher.
4. Males in a copulatory state and females with mature eggs were collected year round although females lacking mature eggs were more common when ground temperatures were higher and the soil was drier, and female egg load was higher under cooler conditions. Females at a stadium 9 or later carried mature eggs and copulatory males tended to be from stadium 8 or later. Different developmental stages could be recovered at all times of the year.
5. These findings indicate persistent populations of O. moreleti across fields throughout the year, with a key breeding period in autumn but likely opportunistic breeding all year. Control of millipedes will need to focus on increasing the impact of biological agents, decreasing suitable habitat for millipede breeding and intensive control at susceptible crop periods.

     

Distribution of the eggs of Aedes punctor (Diptera: Culicidae)

ABSTRACT.

• 1 Eggs of the mosquito Aedes punctor Kirby were found to be aggregated in a horizontal band within woodland depressions.
• 2 The height of the peak of egg density above the lowest point in the depression varied from 24 to 39 cm in six transect studies.
• 3 One depression, 2 m in diameter, was analysed in detail and found to contain a total of 9231 eggs with a maximum density of 944 eggs in a 250 cmz area.

     

The distribution in time and space of parasitism in Epinotia tedella (CI.) (Lepidoptera: Tortricidae)

Abstract.

• 1 The temporal and spatial distribution of parasitism in Epinotia tedella was investigated within two spruce stands.
• 2 Most eggs were laid by the host female early in the season. The parasitoid, Pimplopterus dubius, was subjected to a temporal stress, and it also exhibited a greater oviposition rate early in its life. The temporal distribution of attack frequencies by P.dubius and Apanteles tedellae showed a good adaptation to the phenology of the host.
• 3 The spatial distribution of flight activity indicated a preference to exposed sub-habitats by P.dubius and to dark and sheltered sub-habitats by A.tedellae. The distribution of host larvae showed an aggregation in the lower and central parts of the canopy, and so did the attacks by A.tedellae— even more pronounced. The attacks by P.dubius showed a slightly inverse aggregation pattern. Apparently, the distribution of attacks was caused by preference to physical conditions, rather than local host densities.
• 4 The decreasing log. area of discovery on increasing log. parasitoid density is obviously a ‘pseudo-interference’ phenomenon caused by the aggregation of A.tedellae, and temporal asynchrony in P.dubius.
• 5 P.dubius dominated in young stands and its importance decreased with increasing age of the stands. The importance of A.tedellae was greatest in stands between 20 and 40 years old, and it dominated in those stands that were especially dense and dark, due to absent thinnings.

     

Interaction between flight,reproductive development and oviposition in the pine weevil Hylobius abietis

• 1 The development of reproductive and flight capacity of pine weevils Hylobius abietis during the spring and their dispersal to, and subsequent development at, new clearfell oviposition sites comprise key phases in their life cycle in managed forests. At an old clearfell site where autumn‐emerging weevils had overwintered, weevils were trapped as they re‐emerged in the spring and tested for their ability to fly and then dissected to determine the degree of wing muscle and egg development.
• 2 Re‐emerging weevils were most abundant in pine growing at the edge of the clearfell and, over most of the trapping period (April to June), their capacity for flight (proportion flying and wing muscle width) was more advanced than in weevils from the clearfell itself, with a similar trend in the degree of reproductive development (proportion with mature eggs and egg volume).
• 3 In weevils from the clearfell, flight capacity and reproductive development increased concurrently to a peak around mid‐May. In weevils from pine, wing muscles were already well developed at the start of trapping, although few of them flew. Their more advanced development was attributed to the increased opportunities for maturation feeding after emergence in the previous autumn.
• 4 In the spring, weevils reached the canopy of trees for maturation feeding by walking and, to a lesser extent, by flight. Weevils dispersed by flight to oviposition sites in mid‐May when most of them were reproductively mature. After arrival, flight ability and wing muscle size declined rapidly but egg production was maintained until most weevils had stopped flying. When wing muscles reached their minimum size, there was a marked decline in egg size, suggesting that wing muscle breakdown is important in maintaining egg production at oviposition sites. Prospects for further wing muscle and reproductive development are discussed.

     

Reproductive guilds (maturation,spawning frequency and fecundity) in the black pomfret,Parastromateus niger (Carangidae) in the Kuwaiti waters of the Arabian Gulf

Oogenesis, oocyte maturation pattern, spawning rhythm, spawning frequency, batch fecundity and oocyte diameter–frequency distribution of the black pomfret, Parastromateus niger (Bloch, 1795) in Kuwaiti waters were investigated from October 2003 to September 2005, using histological and morphological methods. The process of development is divided into four major phases: (i) primary growth phase; (ii) secondary growth phase; (iii) maturation phase; and (iv) spawning phase, followed by the regressed phase. Development of the yolky oocyte is an asynchronous process resulting, by the time of oocyte maturation, in a clear differentiation between a ready batch of oocytes (ready for spawning) and a reserve pool. Consequently, P. niger is capable of spawning multiple times throughout the reproductive season. Spawning frequency estimates, based on final oocyte maturation (FOM) method indicated that the species spawns once every 2.8 days during an 8‐month spawning season lasting from February to September, with a potential annual number of 22.4 spawns. Batch fecundity (BF) (2132–2001 648, mean 406 010 eggs), was significantly positively related to both standard length (SL) (P < 0.05) and ovary‐free body weight (OFBW) (P < 0.05), both parameters being good predictors of BF (r² = 30.8% for SL, from 22 cm onwards, and r² = 29.6% for OFBW, from 129.5 g onwards). No significant differences in monthly BF were found throughout the spawning season. Relative batch fecundity was 336 eggs/g OFBW; thus, estimate for potential annual relative batch fecundity was 7526 eggs g^?1 OFBW. The oocyte diameter–frequency distribution analysis revealed a multimodal distribution (at 100–200, 300–400 and 500–700 μm), confirming the evidence of multiple spawning.     

Changes in life-cycle strategies of Carabus problematicus over a range of altitudes in Northern England

ABSTRACT.

• 1 Mandible tip length has been used to estimate the age of individual C.problematicus Herbst caught over an altitude range of more than 700 m in northern England.
• 2 At 100 m the great majority of females laid eggs in the summer of their emergence as adults. The female life-cycle is predominantly annual and 24% only of the egg-bearing individuals were in their second year.
• 3 Above 250 m, most females did not reproduce until the summer of the year following emergence, giving a biennial life-cycle. 96% of egg-bearing females caught above 830 m were in their second year.
• 4 All the males caught during the breeding season at 100 m had emerged within that calendar year and it is concluded that the male life-cycle is annual at this altitude.
• 5 Above 250 m, 83% of the males caught during the breeding season were in their first calendar year, suggesting that recently emerged males may inseminate second year females and also that the male life-cycle is predominantly annual over the whole altitude range studied.
• 6 At the higher temperatures of the lowland site females not only produce eggs in the year of emergence, they also produce more eggs per individual than at the higher sites. Egg production depends on food intake which involves mandible wear and individuals at the lowland site have significantly higher rate of mandible wear than at the sites above 250 m.

     

Chemically mediated multitrophic interactions in a plant–insect vector‐phytoplasma system compared with a partially nonvector species

• 1 We elucidated the life cycles of two jumping plant lice species (Hemiptera: Psyllidae): Cacopsylla picta, a vector of the apple proliferation phytoplasma (Candidatus Phytoplasma mali), and Cacopsylla melanoneura, a nonvectoring species in Germany and some neighbouring countries, which may transmit the phytoplasma in one region in Italy.
• 2 The adults of C. picta reproduce exclusively on apple and migrate soon after emergence (emigrants) to conifers in mountainous regions, and return to apple plants in early spring (remigrants). Cacopsylla melanoneura also uses conifers as overwintering host plants but prefers to reproduce on hawthorn, despite its ability to reproduce on apple.
• 3 Both psyllid species used chemical cues for the identification of their alternate host plants during migration. Remigrants of C. melanoneura preferred the odour of their main reproduction host plant hawthorn to apple but preferred the odour of apple when experienced by feeding and oviposition. Although emigrants of C. picta reportedly prefer the odour of apple trees infected by Ca. P. mali, the remigrants of both species did not distinguish between the odours of infected or uninfected apple plants.
• 4 Investigating the distribution of Ca. P. mali in plant species involved in psyllid life cycle revealed that the phytoplasma is specialized on apple.
• 5 Infection of apple by Ca. P. mali increased mortality and resulted in decreased body size of C. picta offspring.
• 6 Gravid females of C. picta preferred to oviposit on non‐infected plants.
• 7 It is concluded that Ca. P. mali indirectly promotes its acquisition from infected plants and transmission to non‐infected plants by behavioural manipulation of its vector C. picta.

     

Body size distribution in aphids: relative surface area of specific plant structures

Abstract.

• 1 The distribution of the body sizes of British aphids is right-skewed on a logarithmic axis, as in other taxa. Over the size range 2–5 mm there is a marked decrease in numbers of species with increase in size, which on a log log scale has an exponent of -3, The exponent for the right-hand side of the size distribution of British plants is -0.7.
• 2 The sizes of sixty-eight species of the genus Aphis are weakly correlated with the size of their respective host plants.
• 3 An aphid's size is strongly correlated with the length of its proboscis, which indicates the depth to which it has to probe plant tissues in order to feed.
• 4 On average, trees host more species of aphids than either shrubs or herbaceous plants, which appears to be associated with the relative surface area of specific plant structures. The surface area of plants is mainly made of leaves and most species of aphids are leaf feeders. The largest and least numerous species of aphids feed on the branches and trunks of trees, the proportional cover of which is less than that of leaves.
• 5 Taking into account all the above observations, a functional explanation in terms of the relative surface area of specific plant structures is offered to account for the size diversity curve of aphids.

     

Limitation of reproduction by feeding condition in a carabid beetle,Carabus yaconinus

1. Effects of the amount of food consumed on reproduction of the carabid beetle, Carabus yaconinus B., were studied in the laboratory by rearing beetles at different food levels, and the feeding and oviposition rates in the field were estimated on the basis of the relationships between the amount of food consumed, body weight and egg production obtained in the experiment.
2. The maximum amount of food consumed was 150 mg of minced beef per day. The number of eggs laid per day and the mean body weight increased with an increase in the amount of food consumed. High mortality occurred only when the beetles consumed less than 25 mg of minced beef per day.
3. The ratio of current body weight to the minimum one just before death by starvation, W/W_min, was used for the estimation of the rates of food consumption and egg production. The relationships between mean W/W_min ratio, the amount of food consumed and the number of eggs laid per day were clarified.
4. The relationships between ovary states (ovary weight and the number of mature eggs in the ovary) and W/W_min ratio were examined for the females caught in the field. Females with higher values of W/W_min ratio had more mature eggs.
5. The amount of food consumed by females in the field during the reproductive period was estimated to be 50–70% of the maximum value attained in the experiment and the estimated rate of oviposition was 45–59% of the maximum rate attained in the experiment.

     

Ovipositional behaviour and larval performance of Trichoferus campestris (Faldermann) (Coleoptera: Cerambycidae) on cut branches of four North American tree species

1. Velvet longhorned beetle Trichoferus campestris (Faldermann) (Coleoptera: Cerambycidae) is native to Asia. It is reported to be polyphagous in its native range, but hosts have not been screened in its introduced range in the United States.
2. We conducted choice and no-choice host experiments. For choice assays, gravid T. campestris oviposited freely on cut branches of four tree species: Juglans nigra, Malus domestica, Acer saccharum, and Pinus strobus. We investigated oviposition between apple branches with and without cankers. Half of the choice trials underwent winter temperatures.
3. For no-choice assays, eggs were placed on cut branches of these same four species. Half of these branches were later dissected to measure larval development. The rest were exposed to winter temperatures and T. campestris emergence was quantified.
4. Overall, Trichoferus campestris oviposition and development occur more readily on J. nigra and M. domestica than on A. saccharum or P. strobus. The insect oviposited more on cankered than uncankered apple wood. Cold exposure during an overwintering period benefitted insect development in adults.
5. The insect's high degree of polyphagy and ability to reproduce in dry wood has likely facilitated its establishment in multiple locales around the world.

     

Temptations of weevil: feeding and ovipositional behaviour of Hylobius warreni Wood on host and nonhost bark in laboratory bioassays

• 1 Warren root collar weevil Hylobius warreni Wood (Coleoptera: Curculionidae) is a long‐lived, flightless insect native to coniferous forests across northern North America. Girdling by larval feeding causes significant mortality on young trees. The insect poses considerable challenges to reforestation.
• 2 Adult weevils feed on all life stages of a variety of coniferous hosts prior to oviposition. Their relative feeding preferences, however, have not been quantified. Moreover, it is not known whether host bark influences oviposition behaviour.
• 3 Feeding preferences of adult weevils were tested in both choice and no‐choice laboratory bioassays using small branches from three conifers (lodgepole pine Pinus contorta var. latifolia, interior hybrid spruce Picea glauca×engelmannii, and Douglas‐fir Pseudotsuga menziesii) and one deciduous tree (trembling aspen Populus tremuloides). Measurements included the surface area of bark consumed, rate of consumption, the number of days of feeding, and, in the no‐choice assay, the number of eggs oviposited.
• 4 Bark consumption was greatest on pine and Douglas‐fir, followed by spruce. Little to no feeding occurred on aspen. Consumption did not vary between male versus female insects for any of the feeding metrics quantified.
• 5 The presence of aspen branches did not inhibit feeding on any of the other species in the choice bioassays.
• 6 The number of eggs laid by female insects did not differ significantly among tree species in the no‐choice assay. Eggs were laid indiscriminately in the presence of all four host types.
• 7 Results and opportunities for future research are discussed in the context of formulating new integrated pest management strategies for this insect, which is increasingly important in the period of reforestation subsequent to the mountain pine beetle epidemic in western Canada.