Search results for "ampiaiset"
showing 7 items of 7 documents
Social Wasps (Vespinae) in Urban Gardens and Woods
2020
Global change, including urbanization, affects species ecology. Social wasps (Vespinae) are ubiquitous in urban areas, which increases their encounters with humans. We studied social wasps in urban gardens and nearby urban woods in central Finland, using beer traps. Social wasps were common in gardens and woods, and overall wasp abundance was higher in the woods. Also, the most abundant and frequent species Vespula vulgaris was more abundant in the woods than in the gardens. Variation in the overall abundance and the abundance of V. vulgaris was great among trap locations, which likely results from wasps’ social nesting habits. Neither the abundance of all social wasps nor that of V. vulgar…
Different trophic positions among social vespid species revealed by stable isotopes
2021
The social vespid wasps are common insect predators and several species behave in unison in the same biotopes. It is commonly accepted that social wasps are mainly opportunistic generalist predators without differences in prey selection and hence they compete for the same food resources. Trophic positions of six vespid wasp species and their potential prey from four sites in Finland and one in the UK were evaluated using carbon and nitrogen stable isotopes (δ13C and δ15N). The difference in isotope values indicated different trophic positions among species. In general, Dolichovespula spp. showed higher δ15N values than Vespula spp., which suggests that Dolichovespula forage on higher trophi…
Nest characteristics and associates of Dolichovespula (Hymenoptera, Vespidae) in Central Finland
2023
In social vespine wasps, the nest characteristics and associates vary intra- and interspecifically. I studied the nest characteristics and nest associates of three Dolichovespula wasp species in boreal Finland. The average number of combs and cells per nest was similar among D. media, D. saxonica and D. norwegica, and similar to Dolichovespula in the temperate zone. Most D. media and D. saxonica colonies produced both gynes and males, whereas D. norwegica produced mainly either one. The average colony lifespan of D. saxonica was a bit over two months, i.e. shorter than documented for Dolichovespula in the temperate zone. The proportion of nests parasitised by the ichneumonid wasp Sphecophag…
All-day activity of Dolichovespula saxonica (Hymenoptera, Vespidae) colonies in Central Finland
2022
In social vespid wasps, colony activity varies at many temporal scales. We studied the peak season activity (number of individuals entering the nest per min) of colonies of the social vespine wasp Dolichovespula saxonica in its native range in boreal Finland. Six colonies were monitored non-stop for a full day, starting before sunrise and ending after sunset. Shorter monitoring was carried out before and/or after the full-day monitoring. All colonies were active before sunrise and after sunset, and the overall activity was positively linked with colony size. Activity showed irregular minute-to-minute cycles in all colonies. The broader within-day dynamics were idiosyncratic among the coloni…
New insights on the role of ecology and life-history in social evolution
2017
Biological altruism, defined as a behaviour that benefits others at an apparent cost to the focal individual, is found abundantly across different levels of biological organization. While kin selection has been useful for explaining both cooperation and conflict in specialized cooperative societies, more theoretical work has to be done to develop models for realistic ecological and life-history contexts. This thesis aims to fill this gap by providing several new insights on the role of ecology and life-history in various social systems. Firstly, I propose a model that incorporates realistic ecological mechanisms of population regulation and study how different population regulation mechanisms affe…
Biology of the parasitic wasp nest beetle, Metoecus paradoxus (Coleoptera: Ripiphoridae), in Finland
2022
Parasitoids and predators can cause marked mortality in their host species. I studied the occurrence, abundance, and biology of the wasp nest beetle Metoecus paradoxus (Ripiphoridae), inhabiting the nests of the common wasp Vespula vulgaris (Vespidae) in Central Finland. I also compiled phenological data of the species in Finland. The proportion of parasitized nests was 80%. The abundance of the beetle was generally some tens of individuals (max. = 130) per nest, and the parasitism rate 1–18% of the sealed cells, which are typical for the species in temperate Europe. The beetle occurred in several combs but was absent or rare in the oldest and newest combs. Sex ratio was female biased. Fema…
Developing response-ability in human-wasp encounters
2023
Learning to live with unloved others is crucial in the ecological crisis. Unloved wasps are feared and disliked for their sting. Understanding of their ecological importance is increasing, however. Human-wasp encounters are changing with environmental changes, and strategies for multispecies cohabitation are needed. This multispecies study highlights features of wasp biology affecting human-wasp encounters and analyzes how conflicted human-wasp relations could be mitigated. The geographical focus is Finland, in the Northern boreal region. Biological analysis specified spatiotemporal aspects affecting human-wasp encounters: human and wasp habitats and preferences overlap ubiquitously. From a…