Taxonomy, distribution and nesting biology of species of the genus Dolichovespula (Hymenoptera, Vespidae)

The genus Dolichovespula consists provisionally of 18 species. Aerial nest site characteristics have been established for seven species but most of these species show flexibility in their choice of nest sites and two species often nest in shallow subterranean situations. Colony length is usually just over 3 months to approximately 4 months, but at lower latitudes may extend to more than 5 months. Mature colony size is usually approximately 1000 cells with more large cells than small cells. Parasitized colonies have a shorter colony cycle and smaller colonies. During the production of the sexual brood the larva/worker ratio reaches its lowest value of approximately 2.5 larvae per worker. Colonies often have upper mixed combs of small and large cells. Total adult production is usually less than 2000 adults. Colonies of D. arenaria and D. norwegica may specialize in mainly producing males or queens. Variations in mature colony size and production of queens is probably a consequence of the number of workers present, particularly early in the colony cycle.     

Occurrence of the common wasp,Vespula vulgaris (L.) (Hymenoptera: Vespidae) in New Zealand

Abstract

After occurring sporadically in New Zealand since 1921, the common wasp, Vespula vulgaris (L.), was found in March and April 1983 to be established in Dunedin, where 6 nests were discovered. Subsequent examination of museum specimens showed that queens had been collected in Wellington in 1978, and nests by January 1982. Christchurch was invaded in early 1984, several workers were collected near Auckland in March and April 1984, and workers were reported at Nelson in March and May 1984. The Dunedin nests were up to 6 times the size of nests recorded from the Northern Hemisphere, and produced up to 23 times as many new queens. Workers, nest size, and nest productivity were sufficiently different from those reported in western North America to suggest that the New Zealand population originated elsewhere. Colour patterning of the head and pronotum readily separate New Zealand V. vulgaris from New Zealand V. germanica. The nest carton of V. vulgaris is brown; that of V. germanica is grey. Conditions in New Zealand appear to be favourable for V. vulgaris; it can be expected to spread and it may at times reach the high population levels experienced in Europe and the western United States.     

Workers and queens of the European hornetVespa crabro L. have colony-specific cuticular hydrocarbon profiles (Hymenoptera: Vespidae)

Summary Cuticular hydrocarbons were extracted from sixty individual workers from six colonies ofVespa crabro L. and analyzed by combined gas-chromatography/mass spectrometry. Discriminant analysis of the cuticular hydrocarbon profiles of workers and queens showed that the wasps could be grouped by colony and by caste. Stepwise discriminant analysis selected the components which were weighted most heavily in these analyses. Different combinations of cuticular hydrocarbons were important in grouping workers by colony, queens and workers by colony, and workers and queens by caste.     

Landmark Territoriality in the Neotropical Paper Wasps Polistes canadensis (L.) and P. carnifex (F.) (Hymenoptera: Vespidae)

Male Polistes canadensis and P. carnifex aggregate along crests of prominent ridges in Santa Rosa National Park, Costa Rica. At these sites males of both species defend territories (trees and shrubs) by chasing conspecific rivals. Territories do not contain nests or resources that are collected by females. Chasing by territorial males reduces the amount of time spent by intruders in a territory. I describe and contrast male territorial behavior of both species. Some male P. canadensis are territorial while others in the same area exhibit patrolling behavior, flying from one occupied territory to another. Males of P. carnifex exhibit territoriality only. Patrolling in P. canadensis is an outcome of relatively high male density along the ridge, rendering territories in short supply, as shown by the observation that experimentally vacated territories are seized rapidly by formerly patrolling males. Due to a high intraspecific intrusion rate, territorial male P. canadensis spend less time perching and more time flying and chasing intruders from their territories than do male P. carnifex. Males of these two species also differ in the placement of their territories along the ridgeline; P. canadensis occupy territories in saddles while P. carnifex occupy those at peaktops. I show that this divergent spatial pattern is not maintained by competitive exclusion of either species by the other, and I discuss alternative explanations for their separate spatial distributions. Comparative data suggest that males are territorial because females restrict matings to within territories, and I discuss alternative hypotheses to explain this bias in female behavior.     

Unmated queens in the primitively eusocial waspRopalidia marginata (Lep.) (Hymenoptera: Vespidae)

Summary In the primitively eusocial tropical waspRopalidia marginata, five out of eleven colonies studied had an unmated female as their queen. In two colonies this was the case despite the presence of another mated individual in the colony. We found no detectable differences between colonies with unmated queens and those with mated queens. We argue that in species such asR. marginata, where intracolony relatedness is expected to be low and where sociality is likely to be maintained because several individuals have opportunities for direct reproduction in the future, individual selection is likely to override the good of the colony and lead to such phenomena as that of unmated queens.     

Nest and Nestmate Recognition by a Fungus-growing Ant,Apterostigma collare Emery (Hymenoptera: Formicidae)

The ability of Apterostigma collare workers to differentiate their nest from other nests and their nestmates from non-nestmates was examined. In field tests, workers that were removed from their nest were accepted back into their own nests, but were rejected when they were placed onto a nearby (≤ 1 m) nest or a distant (≥ 100 m) nest. In the laboratory, when given a choice between a fragment of their own nest and a fragment of a second nest (near or distant), workers selected their own nest material rather than the material of the second nest. For the nestmate recognition bioassay, two workers from one nest were placed together in an arena with a worker from a second nest. In most bioassays, the nestmates were tolerant of each other, but they were intolerant of the non-nestmate. The results demonstrate that A. collare workers have the ability to recognize nestmates and their nests. The results also suggest that each nest of A. collare is an independent colony.     

Variation in the quality of Vespula vulgaris (L.) queens (Hymenoptera: Vespidae) and its significance in wasp population dynamics

Abstract

Density‐related variation in queen quality has been proposed as a possible mechanism regulating population fluctuations in Vespula species. We investigated annual variation in the quality (size, weight, and fat content) of adult V. vulgaris queens representing four stages of their life cycle (spring, founding, developing, and emerged) taken from six sites in beech forest, South Island, New Zealand. For each queen the dry weight, head width, and thorax length was measured. For a subsample of queens, the fat content was determined by ether extraction. The size of queen cells was measured from a subsample of nests. Size, weight, and fat content of queens varied between wasp colonies and sites. The smallest juvenile queens were under‐represented in the reproductive population. There was no direct link between body size and food supply. Size and weight of developing queens increased as the number of cells in the nest increased. The size of the queen cells varied significantly among layers in a nest and among nests. The under‐representation of small queens in the reproductive population suggests that queen quality may affect survival and/or competitive ability by increasing winter fat storage, nest building activity, and/or success in usurpation disputes.     

Queen succession in the primitively eusocial tropical waspRopalidia marginata (Lep.) (Hymenoptera: Vespidae)

Females of the primitively eusocial wasp Ropalidia marginata can be classified into three behavioral groups: Sitters, Fighters, and Foragers. It has been speculated that both Sitters and Fighters may be hopeful queens and that the Foragers may have little or no opportunities for direct reproduction. Here we show that in 9 of 12 queen-removal experiments where such a behavioral differentiation could be discerned, the individual that became a queen (the potential queen) was a Sitter in 6 cases, a Fighter in 2 cases, and a Forager in only 1 case. Although potential queens spent significantly more time absent from the nest and showed significantly higher rates of dominance behavior compared to the mean values for nonqueens in their colonies, they were intermediate with respect to all behaviors and age when compared to the range of values for nonqueens in their colonies. Potential queens were not necessarily the highest-ranking individuals among the nonqueens. The pattern of queen succession in this species appears to be quite different from the temperate pattern, where an old and active forager of high dominance rank is the potential queen. Although somewhat similar to the tropical pattern of a relatively younger female that has performed relatively little foraging being the potential queen, it is perhaps more accurate to describe the potential queens of R. marginata as unspecialized intermediates.     

Studies of the seasonal development of Vespula vulgaris (L.) (Hymenoptera: Vespidae) with special reference to queen production

An account is given of worker characteristics, worker activities and brood characteristics in nests of Vespula vulgaris. Variations in queen productivity and efficiency of reproduction are discussed.     

Successful and unsuccessful development of colonies of Vespula vulgaris (Linn.) (Hymenoptera: Vespidae)

Abstract.

• 1 Six categories of immature and five categories of mature colonies are described and their developmental relationships suggested.
• 2 Mature brood destroyed by the workers became numerous in 46.4% of the immature colonies. Most of these formed unsuccessful colonies (36.9%) producing few or no queens. The remaining 9.5% recovered to form successful colonies.
• 3 Successful colonies either reared queens only (mean 356 queens), or queens (mean 1461) and males (mean 254) in their large cells.
• 4 The number of small cells in mature colonies correlated with the number of cells built by the founder queen.
• 5 The greater the number of large cells in a mature colony the greater were the chances that a larger proportion of these cells would be used to rear adults.
• 6 The number of small and large cells are correlated in mature successful colonies.
• 7 Queen activity and quality are important factors in the control of colony size and success.
• 8 Selective destruction of male sealed brood in the large cells is linked to worker, rather than queen, control.

     

Variation in colour markings of German wasps Vespula germanica (F.) and common wasps Vespula vulgaris (L.) (Hymenoptera: Vespidae) in New Zealand

Abstract

German wasps (Vespula germanica F.) and common wasps (V. vulgaris L.) both show variations in colour markings in New Zealand. Overlap in the ranges of markings of the head and thorax is limited enough for ready distinction of queens and workers of the two species. Abdominal markings overlap considerably between the species. Colour markings of males were too similar to identify the species, which were completely separated by the shape of their genitalia. The frequency of occurrence of “intermediate” markings in V. germanica populations did not increase in areas where the two species overlap. This suggests there is little or no genetic exchange between the two species.     

日本佳盾蜾蠃的生物学特性观察

日本佳盾蜾蠃Euodynerus nipanicus（Schulthess）是一种重要的独栖捕食性天敌昆虫,对我国南方林区鳞翅目蛾类害虫的控制具有一定作用。本文报道了日本佳盾蜾蠃的形态特征、生活史及幼虫和成虫的行为等生物学特性。该蜂在江西赣州地区 1 年发生 4 代,以滞育的老熟幼虫在巢管虫室内越冬,滞育期约 190 d。翌年的4月下旬成虫开始外出活动,主要包括交配、筑巢、产卵、捕食等行为。通过野外收集筑巢巢管,室内饲养观察等,发现该蜂的卵近似微弯的长圆柱形,长 2.912 ± 0.127 mm,卵期2-4 d,平均 2.5 ± 0.99 d;非越冬幼虫期 8. 1 ± 0. 99 d;预蛹期4.3 ± 0. 48 d;蛹期7. 4 ± 0.84 d;雌雄比约为 2. 95:1。本研究丰富了日本佳盾蜾蠃的生物学基础知识,为进一步利用该蜂防治南方林区鳞翅目蛾类害虫提供了依据。     

Competition for landmark territories among male Polistes canadensis (L.) (Hymenoptera: Vespidae): large-size advantage and alternative mate-acquisition tactics

Alternative male mating tactics of insects at landmarks (leks)have only rarely been investigated. Some males of the paperwasp, Polistes canadensis (L.), were territorial at small treesalong the crests of dry ridges in Santa Rosa National Park,Costa Rica. Territories did not contain nests or resources forwhich females foraged. Contrary to other "hilltopping" species,male P. canadensis competed most intensely for territories insaddles along these ridges rather than at the highest points.Nonterritorial males patrolled small areas of the ridge line,following a path that took them to a number of territories.Many males switched between territoriality and patrolling, suggestingthat both size-related tactics belong to one conditional strategy.Males that were territorial on 2 or more days were larger thanthose that were territorial on only 1 day, and these in turnwere larger than permanent patrollers. Moreover, the mean sizeof territorial males was positively correlated with two measuresof territory attractiveness, suggesting that larger males monopolizepreferred sites. Mean age of territorial males was also relatedto territory attractiveness, but males of intermediate age claimedthe most attractive territories.