Åsa Berggren

Swedish University of Agricultural Sciences Sweden · Department of Ecology

The emerging insects-as-food industry is increasingly promoted as a sustain- able alternative to other animal protein production systems. However, the exact nature of its environmental benefits are uncertain because of the overwhelming lack of knowledge concerning almost every aspect of production: from suitable species, their housing and feed requ...

Insects as food show a large variation in traditional use over the world. This high variation between countries in combination with current ideas of insects as part of a solution to feed a growing global population raises interesting questions. The aim of this paper is to investigate what has been perceived as food historically and how this changes...

Disease-induced personality change results from endogenous and adaptive host responses or parasitic manipulation. Within animal husbandry systems understanding the connection between behaviour and disease is important for health monitoring and for designing systems considerate to animal welfare. However, understanding these relationships within ins...

After finishing the PhD, the researcher enters a stage in their early research career where more independence is expected. Within a relatively short time period, the researcher needs to gather research experience and support in the form of tangible resources as funding, and intangible resources like access to research networks, close collaborations...

Managing road verges to promote diverse and flower-rich plant communities has been proposed to mitigate the decline of pollinating insects caused by the loss of natural and semi-natural habitat. There is, however, a concern that flower-rich road verges can be ecological traps for pollinators as insects might be attracted to a habitat where there is...

To understand colonization success of an invasive species we need to know the origin of the founders, where and when they were introduced, and how they spread from the introduction site(s) through the landscape. Admixture of different genetic lineages from multiple introductions is generally hypothesized to be beneficial to invasive species thanks...

Roads and road verges can potentially have opposite impacts on organisms that move through the landscape. While road verges can be habitat for a large number of species, and have been proposed to act as dispersal corridors, roads can act as barriers to movement. This duality of roads and road verges has however rarely been assessed simultaneously,...

The art of population modelling is to incorporate factors essential for capturing a population's dynamics while otherwise keeping the model as simple as possible. However, it is unclear how optimal model complexity should be assessed, and whether this optimal complexity has been affected by recent advances in modelling methodology. This issue is pa...

Floral resource quantity in agricultural landscapes plays a key role in the persistence of wild pollinators. An equally important, but less investigated factor is how variation in floral resource availability over time, e.g. floral resource pulses, affects pollinator abundances and diversity. Despite the potential importance of late-season resource...

Insects generally have high reproductive rates leading to rapid population growth and high local densities; ideal conditions for disease epidemics. The parasites and diseases that naturally regulate wild insect populations can also impact when these insects are produced commercially, on farms. While insects produced for human or animal consumption...

One of the fundamental questions in invasion biology is to understand the genetic mechanisms behind success or failure during the establishment of a species. However, major limitations to understanding are usually a lack of spatiotemporal population data and information on the populations' colonisation history. In a large-scale, detailed study on t...

Orthopteran insects have high reproductive rates leading to boom-bust population dynamics with high local densities that are ideal for short, episodic disease epidemics. Viruses are particularly well suited for such host population dynamics, due to their supreme ability to adapt to changing transmission criteria. However, very little is known about...

House crickets (Acheta domesticus) are increasingly being used as food. This has the potential for a more efficient food production that also may benefit agroecosystems. As the first study to compare feeds based on European wild flowering plants as feed for house crickets we examined five common plants known to support biodiversity of wild insects...

Background Morphological differentiation between populations resulting from local adaptations to environmental conditions is likely to be more pronounced in populations with increasing genetic isolation. In a previous study a positive clinal variation in body size was observed in isolated Roesel’s bush-cricket, Metrioptera roeselii , populations, b...

Morphological differentiation between populations resulting from local adaptions to environmental conditions is likely to be more pronounced in populations with increasing genetic isolation.

Inbreeding depression is an important long-term threat to reintroduced populations. However, the strength of inbreeding depression is difficult to estimate in wild populations because pedigree data are inevitably incomplete and because good data are needed on survival and reproduction. Predicting future population consequences is especially difficu...

The tendency of species richness to increase with patch area is one of the most robust empirical generalisations in ecology and its logic drives conservation actions. Indeed, preference is often given to conserving large, highly connected areas over small isolated patches. However, small habitats have been shown to be important biodiversity refuges...

This study evaluated the potential of red clover as a sole diet for house crickets (Acheta domesticus, AD) and the effect of ensiling or drying red clover biomass on growth, survival and water consumption of AD. Wild AD were caught near Uppsala, Sweden, and reared in a climate-controlled room under a 12-h light regime. One day-old third-generation...

Background: The relationship between humans and insects goes long back and is important. Insects provide a multitude of ecosystem services for humans, e g. by pollinating crops and decomposing matter. Our current knowledge about the cultural ecosystem services that insects provide is limited and not much examined. Method: Scattered ethnographica...

Research in historical ethnobiology can provide us with information about little known and seemingly quite insignificant practices in the past. The utilization of insect products as foodstuff is a rare custom in Europe and data on this are scarce. From the Nordic countries, we have information about producing ant schnapps with the help of the red w...

The European house cricket (Acheta domesticus) is a species of interest for the emerging insect-as-food industry.Acheta domesticusdensovirus (AdDV) is a member of the Parvoviridae virus family which infectsA. domesticus,causing widespread mortality and even extinction of local cricket populations. Despite the well-known detri-mental effects of AdDV...

As wild harvesting of insects gives way to mass rearing, there is an urgent need to develop expertise and methods in insect animal husbandry and facility design. In order to advance the science of animal husbandry and production in this field, comparisons and contrasts of different insect rearing facilities currently in production are likely to be...

Insect production has been suggested as a food production system that could be more sustainable than many conventional livestock systems. Insects are a promising source of nutrients for humans containing high amounts of good quality protein, fatty acids, vitamins and minerals. A sustainable insect industry could have large impacts on land use, ecol...

This study evaluated diets including whole or peeled (legs removed) crickets (Teleogryllus testaceus) in terms of diet digestibility, growth and nitrogen retention, using pigs as an animal model. The experiment included three isonitrogenous diets (18.4% crude protein) including either whole cricket meal (WC), body cricket meal (legs removed, BC) or...

This study evaluated survival and growth of Cambodian field crickets (Teleogryllus testaceus) during captivity when fed a set of local weed species, agricultural and food industry by-products. Wild individuals were caught at two locations in Cambodia, kept in pens and fed commercial chicken feed until the second generation off-spring hatched. First...

Residuals of four genetic measures plotted against geographic distance (km) from the range centre and towards the range edge. There was a positive correlation between distance and variability around the mean for all estimates (AR: p = 0.012, UHe: p = 0.003 and FIS: p = 0.009) except for PAR, for which the correlation was negative

Metrioptera roeselii microsatellite markers. Primer names, GenBank accession numbers, fluorescent dyes, PCR multiplex and mean number of alleles corrected for sample size for the 13 microsatellite loci used. Forward (5’-3’) primers were directly labelled with FAM (blue), VIC (green), NED (black) or PET (red) fluorescent dye

Identifying sources of range expansions after an introduction event and understanding the species dispersal are essential for effective management of invasive species. In a unique study system we investigated the spread and distribution of genetic diversity subsequent to a known colonization event and in the light of the well-known biology of the r...

Context Habitat heterogeneity is often assumed to benefit farmland biodiversity. Increasing heterogeneity of non-crop habitats is often too costly in terms of agricultural production. It has been suggested that increased crop heterogeneity could mitigate the negative effects of intensification on biodiversity while still maintaining high production...

Both the environment and the spatial configuration of habitat patches are important factors that shape community composition and affect species diversity patterns. Species have traits that allow them to respond to their environment. Our current knowledge on environment to species traits relationships is limited in spite of its potential importance...

Information on exotic species' current and potential distribution is vital for decisions on management. Species distribution models can predict where colonizations are likely; however, the collection of species' distribution data over large areas in order to parameterize the models is costly. Therefore, modelling methods that are able to use low-co...

Species range shifts associated with environmental change or biological invasions are increasingly important study areas. However, quantifying range expansion rates may be heavily influenced by methodology and/or sampling bias. We compared expansion rate estimates of Roesel's bush-cricket (Metrioptera roeselii, Hagenbach 1822), a nonnative species...

Newly founded isolated populations need to overcome detrimental effects of low genetic diversity. The establishment success of a population may therefore depend on various mechanisms such as assortative mating, purging of deleterious alleles, creation of new mutations and/or repeated inflow of new genotypes to reduce the effects of inbreeding and f...

Apalus bimaculatus (Linnaeus) (Coleoptera: Meloidae) is a beetle currently managed for conservation in Sweden. The species inhabits at-risk ephemeral and patchily distributed sandy habitats. However, little is known about its ecology and the factors important for its distribution. We censused 158 discrete sand patches within 31 potential sites for...

The bush-cricket Metrioptera roeselii is an example of an insect which has expanded its indigenous range beyond expectations based on its natural dispersal potential. Understanding how species colonize new areas is vital for formulating effective species conservation programmes and managing invasive species. The aim of this research is to use mitoc...

Linear landscape elements are generally considered beneficial for promoting the movements of species between isolated habitats. However, relatively little consideration has been given to the effect of interconnections (nodes) between these elements: e.g. a simple linear element offers limited options for movement, whereas a network of such structur...

Citation: Preuss S, Cassel-Lundhagen A, Berggren Å (2011) Modelling the distribution of the invasive Roesel's bush-cricket (Metrioptera roeselii) in a fragmented landscape. NeoBiota 11: 33–49. Abstract The development of conservation strategies to mitigate the impact of invasive species requires knowledge of the species ecology and distribution. Th...

1.Adams and Zhang recently published one of the best studies so far of patterns of insect folivory along a latitudinal (climatic) gradient. They show clear negative trends in foliage loss in relation to temperature for certain groups of insect herbivores. 2.Although their suggestion that the plant–herbivore interaction may be more important in cool...

Variation in morphological traits along latitudinal gradients often manifests as size clines. In insects, both positive and negative correlations are seen, and the mechanism behind the response is unclear. We studied variation in seven morphological traits of Roesel’s bush cricket, Metrioptera roeselii, sampled from seven latitude-matched-pair popu...

Abstract Despite the growing interest in how an individual's immune response is correlated to morphological and ecological factors, little empirical data has been available from wild insect populations. Many insects have different color morphs and exhibit differences in immune responses. Links are expected to exist between body colors and immune fu...

This article documents the addition of 411 microsatellite marker loci and 15 pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Acanthopagrus schlegeli, Anopheles lesteri, Aspergillus clavatus, Aspergillus flavus, Aspergillus fumigatus, Aspergi...

Despite interest in the relationship between fluctuating asymmetry (FA), immune response and ecological factors in insects, little data are available from wild populations. In this study we measured FA and immune response in 370 wild-caught male bush-crickets, Metrioptera roeseli, from 20 experimentally introduced populations in southern-central Sw...

Current predictions regarding the ecological consequences of climate change on animal populations are generally autecological and species-specific, and/or non-mechanistic extrapolations of recent short-term patterns. To better understand and predict the effects of climate change on the distribution of species and the abundance of populations we off...

Despite the growing interest in relationships between ecological variables and individual immune function, few empirical data have been available from wild populations. In this study, I assayed the immune response from 370 wild-caught bush-crickets, Metrioptera roeseli, from 20 experimentally introduced populations, by measuring individual encapsul...

Artificial nests are frequently used to assess factors affecting survival of natural bird nests. We tested the potential for artificial nests to be used in a novel application, the prediction of nest predation rates at potential reintroduction sites where exotic predators are being controlled. We collected artificial nest data from nine sites with...

The extent of darkening of melanin‐based plumages in birds has previously been linked with increasing aggressive encounters between individuals. The North Island robin (Petroica longipes) is a territorial New Zealand endemic passerine that displays delayed plumage maturation (darkening of the plumage with age). Aggressive boundary interactions in t...

Complex interactions between an individual's genotype and its environment determine characteristics such as body size. However, gene-environment interactions should not be seen as being restricted to individual ontogeny: the diversity of the local gene pool can be greatly influenced by habitat variables and population history (e.g., landscape conne...

We thank Armstrong et al. (2008) for raising specific concerns about habitat fragmentation research in their paper “Avoiding hasty conclusions about effects of habitat fragmentation,” as these concerns are important and deserve to be highlighted. As a forum for exploring these issues, Armstrong et al. chose to single out our paper (Wittern and Berg...

Natal dispersal is an important component in bird population dynamics and can influence the persistence of local and metapopulations. We examined natal dispersal in the North Island robin (Petroica longipes), a sedentary bird species distributed in a fragmented forest habitat on Tiritiri Matangi Island, New Zealand. Earlier studies have shown that...

Natal dispersal is an important component in bird population dynamics and can influence the persistence of local and metapopulations. We examined natal dispersal in the North Island robin ( Petroica longipes), a sedentary bird species distributed in a fragmented forest habitat on Tiritiri Matangi Island, New Zealand. Earlier studies have shown that...

Behavioural laterality, where an individual shows a preference for using its left or right side when engaging in a task, has been documented in a wide range of species. Typically, such preferences have been correlated with neurological biases associated with brain structure, genetics, sex, and age. In birds, behavioural laterality (and footedness)...

The North Island Robin (Petroica longipes) is an endemic New Zealand passerine with melanin-based plumage of grey-brown and black, with males typically described as having darker plumage than females. In this study we quantified the relationship of sex and age on plumage colour in 32 North Island Robins on Tiritiri Matangi Island, New Zealand. We o...

Intraspecific foster feeding and adoption has rarely been observed in birds, with the exception of waterfowl. In this study, I document for the first time the existence of intraspecific foster feeding and adoption of fledglings by adult passerines with their own young. During a three-year study of the North Island robin (Petroica longipes), a speci...

A 3-year-old female North Island robin (Petroica longipes) was found dead on Tiritiri Matangi Island during the breeding season. The bird was in poor condition, and there was a 13 x 8 mm granulomatous mass in the thoracic cavity causing displacement of the heart and left lung. Histologically, the mass was a large granuloma infiltrated with fungal h...

  1. Individual movement behaviours of male Roesel's bush crickets were compared between individuals experimentally released with or without conspecifics.2. Differences in movement behaviour were recorded between the groups, with individuals released with conspecifics moving faster and further.3. The study shows that behavioural interactions betwee...

Conservation efforts involving introductions, reintroductions, and translocations of populations have an inherent and inescapable problem of small initial populations. Small founding populations are likely to have a small proportion of the genetic variability carried by the original population. This may manifest phenotypically through changes in in...

Cloacal protuberances (CP) in male birds result from spermatic engorgement of storage tubules around the cloaca during the breeding season. We examined seasonal changes in the volume and orientation of the CP in the New Zealand stitchbird Notiomystis cincta. The male stitchbird has one of the largest recorded CPs for any species (max = 1,570mm3), w...

Birds are hosts to many blood-sucking ectoparasites, with these parasites having diverse and wide-ranging effects on the health, reproductive success and behaviour of their hosts. Louse flies Ornithoica sp. (Rondani) (Diptera: Hippoboscidae) are common parasites on bird species around the world and have been found to be vectors for both blood paras...

Pathological consequences of the blood-sucking mite Ornithonyssus bursa vary between species, with its impact ranging from no measurable effect, to significant blood loss and chick mortality. In New Zealand, where several bird species are known to be parasitised by O.bursa, the effect of this mite on host fitness is unclear, as few studies have bee...

Background The colour of animals' skin, fur, feathers or cuticula has been estimated in a large number of studies. The methods used to do so are diverse, with some being costly and not available to all researchers. In a study to measure plumage colour in a bird species, a new method of creating a colour chart was developed. While colour-charts have...

Many bird species show delayed plumage maturation (DPM), retaining sub-adult plumage until after their first breeding season. Most explanations assume that DPM increases fitness over the breeding season. However, unless birds undergo a full moult before breeding, DPM could also be an adaptation to increase survival over the previous winter. The win...

One aid to understanding species distribution patterns is to gather detailed information on individual movement behavior. To gather information on dispersal capabilities in Roesel''s bush-cricket Metrioptera roeseli an individual-based study was carried out. In four areas with two different cattle grazing regimes 35 individuals were released and th...

Although plastic and metallic leg bands are widely used for identifying individual birds to assist population monitoring, the health risks associated with banding are quantified relatively rarely. We recorded the general occurrence of foot and leg injuries during a four-year study of the North Island robin (Petroica longipes) and assessed the proba...

One method proposed for moderating the negative effects of habitat isolation is the preservation or restoration of linear landscape elements that structurally link isolated habitat remnants. An understanding of how animals react to landscape elements and move through the landscape is vital for species management and theory development. To achieve t...

Summary1.Fragmentation and habitat loss affects both existing and introduced populations. Small habitat areas may have harsher biotic and abiotic conditions, as well as restricting population sizes. Loss of connectivity reduces the opportunities for individuals to move between patches to rescue populations or to re-colonize patches. Knowledge of ho...

Assessing the colonizing ability of a species is important for predicting its future distribution or for planning the introduction or reintroduction of that species for conservation purposes. The best way to assess colonizing ability is by making experimental introductions of the species and monitoring the outcome. In this study, different-sized pr...

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2001. Consists chiefly of 4 papers submitted to or published in journals, 2 of which are co-authored with other writers. Includes bibliographical references.

The bush cricket, Metrioptera roeseli (Orthoptera, Tettigoniidae), occurs in patchy and heterogeneous agricultural landscapes. Such a mosaic of different types of grassland habitats causes spatial variation in local population density. Low population densities may result in fewer mating opportunities that can give rise to an Allee effect, possibly...