Magne Husby

• Professor
• Nord University

Many birds suffer heavily from nest predation, selecting several behaviours to avoid the risk. Corvids are among the most serious nest predators. However, they are also among the most neophobic of any birds. We suggest that nesting birds may take advantage of this fear by decorating the nest with anthropogenic materials that are novel to the predat...

Roadkill is widely recognized as one of the primary negative effects of roads on many wildlife species and also has socioeconomic impacts when they result in accidents. A comprehensive dataset of roadkill locations is essential to evaluate the factors contributing to roadkill risk and to enhance our comprehension of its impact on wildlife populatio...

Birds and other wildlife are negatively affected by many anthropogenic activities, including human recreational activities, which are often not considered in area planning. Here, I present factors affecting the flight initiation distance (FID)—the distance to an approaching human at which birds flee—for 1075 different flocks of waterbirds. The FID...

Cover photo: Hooded Crow Corvus cornix. Photo: Terje Lislevand. Non-vocal sounds made by rapid closing of the bill are well known among many bird species, including several corvids. However, this is the first documentation of bill clapping by a Hooded Crow Corvus cornix during aggressive encounters with a conspecific. The aggression level was low,...

This is a poster presented in the poster session at the Asian Ornithological Conference 2024.

Coastal wetlands are one of the most threatened ecosystems due to, firstly, their relative rarity and, secondly, the strong human interest in these coastal sites for infrastructure development, and recreation. These coastal wetlands also serve as important migration stopover sites for a range of waterbirds. There is great international interest in...

Investigations of seasonal variations in nest predation rates yield highly variable results. Some investigations argue that search image is responsible for some of the nest-predation patterns, but as far as we know, this study is the first in which search image in connection with seasonal variation in nest-predation rate has been experimentally tes...

Wind power is commonly used to reduce greenhouse gas emissions but often has negative effects on biodiversity. In this study, I investigated the effects of wind farm and power line construction on the territory status of the Eurasian goshawk Accipiter gentilis, whether fledglings were produced or not, and the number of fledglings. Included were 55...

Cover photo: Great Tit male. Photo: Alf Tore Mjøs. Birds may sing to defend a territory and to attract a mate. However, despite many studies clear conclusions remain on how ecological conditions affect the song, such as physical obstacles that may reduce the sound transmission, and anthropogenic noise that may mask the signal. The social environmen...

Declines in European bird populations are reported for decades but the direct effect of major anthropogenic pressures on such declines remains unquantified. Causal relationships between pressures and bird population responses are difficult to identify as pressures interact at different spatial scales and responses vary among species. Here, we uncov...

Aim Species distribution models (SDMs) are widely used to make predictions on how species distributions may change as a response to climatic change. To assess the reliability of those predictions, they need to be critically validated with respect to what they are used for. While ecologists are typically interested in how and where distributions wil...

Climate change has dramatic impacts on ecological systems, affecting a range of ecological factors including phenology, species abundance, diversity, and distribution. The breadth of climate change impacts on ecological systems leads to the occurrence of fingerprints of climate change. However, climate fingerprints are usually identified across bro...

Simple Summary Wind power can contribute to a necessary reduction in CO2 and other greenhouse gas emissions. However, wind farm construction and infrastructure might cause other problems, for example, reducing biodiversity. In parts of their distribution area, eagle owls are scarce and declining, and not much is known about their tolerance for diff...

After more than a century of persecution and low reproduction rate, the Eagle Owl is extinct, scarce or still declining in many areas. One possible mitigating action is to supply them artificially with food, but earlier experiments with supplementary feeding of other species have produced varying effects. Supplementary feeding has some caveats and...

Around fifteen thousand fieldworkers annually count breeding birds using standardized protocols in 28 European countries. The observations are collected by using country-specific and standardized protocols, validated, summarized and finally used for the production of continent-wide annual and long-term indices of population size changes of 170 spec...

Around fifteen thousand fieldworkers annually count breeding birds using standardized protocols in 28 European countries. The observations are collected by using country-specific and standardized protocols, validated, summarized and finally used for the production of continent-wide annual and long-term indices of population size changes of 170 spec...

Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in thes...

The continued global biodiversity crisis necessitates the continuation and development of new well‐designed monitoring strategies and action plans with particular focus on under‐represented countries and regions. However, limited resources in terms of budget and availability of qualified field personnel can restrict the geographical coverage of mon...

An Osprey Pandion haliaetus was observed by eight people as it was dragged under water by a fish and drowned. Several unsuccessful attempts to leave the water surface caused the Osprey gradually to sink in the water until it disappeared. The area was searched by boat, but the fish and Osprey were gone, and it was confirmed that there were no fishin...

The Common Crane (Grus grus) population has experienced an unprecedented increase across Europe during the last decades. Although cranes feed mostly on invertebrates, amphibians and berries during the breeding season, they can also eat eggs and young of other birds. Therefore, conservationists have raised concerns about the potential predatory effe...

The greatest loss of biodiversity in the EU has occurred on agricultural land. The Common Starling (Sturnus vulgaris) is one of the many numerous and widespread European farmland breeding bird species showing major population declines linked to European agricultural intensification. Here we present results based on monitoring data collected since 1...

Climate change is a major global threat to biodiversity with widespread impacts on ecological communities. Evidence for beneficial impacts on populations is perceived to be stronger and more plentiful than that for negative impacts, but few studies have investigated this apparent disparity, or how ecological factors affect population responses to c...

The greatest loss of biodiversity in the EU has occurred on agricultural land. The Common Starling (Sturnus vulgaris) is one of the many numerous and widespread European farmland breeding bird species showing major population declines linked to European agricultural intensification. Here we present results based on monitoring data collected since 1...

We examined relative age effects (RAE) in national test results in reading literacy in Norway in 2013, in Grades 5, 8, and 9 students (n = 173,421) to estimate how month of birth is associated with mean scores and different achievement levels. The results confirm that there is an approximately linear decrease in test scores across months of birth f...

A large array of species distribution model (SDM) approaches has been developed for explaining and predicting the occurrences of individual species or species assemblages. Given the wealth of existing models, it is unclear which models perform best for interpolation or extrapolation of existing data sets, particularly when one is concerned with spe...

Nest predation studies often use artificial nests to secure sample sizes and nest distribution patterns that allow empirically testing differences in predation rates between ecological units of interest. These studies rely on the assumption that natural and artificial nests experience similar or consistent relative predation rates across ecological...

Data file with all observations used for analysis. (CSV)

Dependency of exposure time effect on categorization of exposure time in nests observed at both 10 and 25 days. Effect sizes of predictor variables explaining variation in nest predation rates based on dataset where all nests observed at both 10 and 25 days were categorized as having 25 days exposure time. (DOCX)

Distribution of nest types according to exposure time. The table highlights how nest belonging to different nest type categories are distributed between 10 and 25 days exposure time in the dataset used for analysis in the paper, and for two alternative datasets where all nests observed after both 10 and 25 days are defined as having exposure time o...

Model building and checking. Model building procedure with model checking and evaluation from original binomial regression model with complementary log-log link and exposure time as offset. Including r code used for analysis. (PDF)

Mountain areas often hold special species communities, and they are high on the list of conservation concern. Global warming and changes in human land use, such as grazing pressure and afforestation, have been suggested to be major threats for biodiversity in the mountain areas, affecting species abundance and causing distribution shifts towards mo...

Despite nest predation being the most common cause of breeding failure in open-nesting birds, we have little insight into the cues used by nest predators when they search for nests. So far we have assumed that nest-predating birds are visually oriented while mammal predators to a large extent use scent and auditory cues like nestling begging calls....

Nest predation is the most important factor causing reproductive failure in open-cup nesting birds. Therefore, it represents a strong selection agent shaping reproductive strategies. To understand how predation affects avian populations, it is crucial to understand how predation effects on nesting success vary in space and time, and which ecologica...

Nest predation is one of the most important causes of nest failure in breeding birds and can vary extensively between sites and years. Different mechanisms governing predation rates may dominate in different years and this annual variation should therefore be evaluated directly. Here we document year-to-year variation in nest predation rates in two...

Urban environments present novel and challenging habitats to wildlife. In addition to well-known difference in abiotic factors between rural and urban environments, the biotic environment, including microbial fauna, may also differ significantly. In this study, we aimed to compare the change in microbial abundance on eggshells during incubation bet...

Northern European peatlands are important habitats for biological conservation because they support rich biodiversity and unique species compositions. However, historical management of peatland habitats has had negative consequences for biodiversity and their degradation remains a major conservation concern. Despite increasing awareness of the cons...

Information about the relative frequency and geographical variation of colour aberrations in birds is rare. By entering the word Magpie Pica pica in 37 European languages into an Internet search engine, I was able to trace 3,974 photographs in 2015 and 3,672 photographs in 2016 in more than 40 countries. By analysing the photographs, I found a sign...

Of the many negative effects roads have on wildlife, vehicle-caused mortality is important, killing several hundred million birds on an annual basis worldwide. Mortality is often the result of sitting on the road and failing to avoid an approaching vehicle, or being hit by a car while flying across the road at too low height. Therefore, one would e...

Several hundred million birds are killed on an annual basis worldwide due to collisions with vehicles. While this is well documented, less data exists on specific factors affecting the number of roadkills. I examined roadkill patterns while driving a car during a 44-month period (617 days, twice daily) along a 25 km stretch of road in the middle of...

Based on phenotypes, two subspecies of Eurasian Magpies (Pica pica) are recognized in Norway, with nominate P. p. pica in southern Norway, and P. p. fennorum in northern Norway. In this study, we investigated whether there are genetically distinct groups of Magpies in Norway, which can be considered in the discussion of the subspecies status. We co...

Birds populations allied in abundance Changes in climate can cause populations of species to decline, to increase, or to remain steady. Stephens et al. looked across species of common birds in Europe and the United States. Despite many differences between the two regions, expectations about how a species might respond to climate change did predict...

Two yellow and black Common Magpies Pica pica were observed in Sømna, Norway, in 2014. The normally white parts of these birds were all evenly coloured yellow, while the black parts looked normal. Carotenoids are normally responsible for yellow colours in feathers, but Magpies are not among the bird species for which carotenoids have been identifie...

<http://www.artsdatabanken.no/Rodliste/Artsgruppene/Fugler>.

Large-scale and population-wide monitoring of waders on their boreal and arctic breeding grounds has hitherto been lacking, mainly because logistics are truly challenging in regions with few ornithologists, vast areas and few roads. In Norway, Sweden and Finland (here ‘Fennoscandia’) there are now national monitoring schemes in place, aimed at trac...

Among the most widespread forms of anthropogenic modification of the natural landscape is road construction, with vehicle mortality a major issue affecting amphibians, reptiles, mammals, and birds. Why some species are more susceptible to vehicle collision than others, however, is poorly understood. We examine how roadside vegetation patterns, road...

Fugler har flere egenskaper som gjør dem egnet som indikatorer for miljøtilstand. Her presenterer indekser for hekkebestander for 55 terrestriske fuglearter for perioden 1996-2013 og for ytterligere 21 arter for perioden 2006(2008)-2013. Rapporten gir også en mer detaljert presentasjon av metodene som benyttes i den landsrepresentative overvåkingen...

Large-scale multi-species data on population changes of alpine or arctic species are largely lacking. At the same time, climate change has been argued to cause poleward and uphill range shifts and the concomitant predicted loss of habitat may have drastic effects on alpine and arctic species. Here we present a multi-national bird indicator for the...

1. Predators impose costs on their prey but may also provide benefits such as protection against other (e.g. nest) predators. The optimal breeding location in relation to the distance from a nesting raptor varies so as to minimize the sum of costs of adult and nest predation. We provide a conceptual model to account for variation in the relative pr...

THE NORWEGIAN BIRD REPORT 2000 - a report on locally uncommon and scarce birds in Norway in 2000, by the Norwegian Bird Records Committee (NFKF)The basis of this report is the annual reports produced by the county rarities committees. For 2000 all the counties, with the exception of Finnmark and Sogn og Fjordane counties contributed to the report....

This project is a part of an ongoing work to establish a system for monitoring terrestrial biodiversity in Norway. Its goal is to evaluate the design and practicality of a system for monitoring birds based on a systematic grid where NGOs (Norwegian Ornithological Society, NOF) take part in the data collection. This evaluation covers both the practi...

This is NFKF's 9th annual report, covering locally uncommon and scarce species and subspecies. Whenever possible, focus is made on ttrends in occurrence - both between years as well as on a more long-term scale. Reports and coverage from each county vary, so in some cases it can be difficult to compare variations both between each county and betwee...

Young Magpies left the nest when about 33 d old, independent of sex, body size, and brood size, but nest-leaving was positively correlated with the age differences within the brood. Fledglings were observed searching for food on the ground for the first time when about 45 d old, females about three days earlier than males (ns). The young stayed tog...

In experimental studies of avian hatching paterns offspring sex has been neglected. This may be a problem if nestling growth and mortality is sex biased, and if this bias is influenced by hatching spread. In a field study of two crow species, the magpie Pica pica and the hooded crow Corvus corone cornix, we manipulated hatching spread. Both species...

Magpie nestlings were studies at Trondheim, C Norway. The magpie is a sexually size-dimorphic species, the male being about 12% heavier than the female at fledging. This size-dimorphism develops gradually during the nestling period. Tarsus length, wing feather length, bill tip length and body weight are the recommended morphological variables for a...

(1) Broods of the magpie Pica pica (L.), in an urban habitat in Norway, were manipulated to test the brood reduction hypothesis. According to this theory parents adjust their brood size to the maximum number of young which they are capable of rearing by allowing the smallest nestlings to die. (2) I created three groups of nests: (i) nests where all...

Using data from the field and the literature on 67 species of birds, we analyzed intraclutch variation in egg size, especially the deviation of the last egg from the clutch mean (D). Values of D are closer to zero in precocial than in altricial species; D is negatively correlated with body size in interspecific comparisons, i.e. large birds, includ...