English
norskBlar i forfatter "Sandvik, Hanno"
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Alien plants, animals, fungi and algae in Norway: an inventory of neobiota
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-03)We present the results of an inventory and status assessment of alien species in Norway. The inventory covered all known multicellular neobiota, 2496 in total, 1039 of which were classified as naturalised. The latter constitute c. 3% of all species known to be stably reproducing in Norway. These figures are higher than expected from Norway’s latitude, which may be due a combination of ... -
Alien species in Norway: results from quantitative ecological impact assessments
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-20)1. Due to globalisation, trade and transport, the spread of alien species is increasing dramatically. Some alien species become ecologically harmful by threatening native biota. This can lead to irreversible changes in local biodiversity and ecosystem functioning, and, ultimately, to biotic homogenisation.<p><p> 2. We risk-assessed all alien plants, animals, fungi and algae, within certain ... -
Centennial relationships between ocean temperature and Atlantic puffin production reveal shifting decennial trends
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-24)The current warming of the oceans has been shown to have detrimental effects for a number of species. An understanding of the underlying mechanisms may be hampered by the non-linearity and non-stationarity of the relationships between temperature and demography, and by the insufficient length of available time series. Most demographic time series are too short to study the effects of climate on ... -
Climate fluctuations and differential survival of bridled and non-bridled Common Guillemots Uria aalge
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012-06-22)Climate fluctuations and its effects on ecological processes are evident in most areas worldwide but whether such climatic effects are induced phenotypic plasticity or whether animals adapt to the new environment through micro‐evolutionary processes is poorly known. In this study we have analyzed long‐term data (22 years) on the relationship between climatic fluctuations and the adult survival of ... -
Climate-Driven Ichthyoplankton Drift Model Predicts Growth of Top Predator Young
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013-11-12)Climate variability influences seabird population dynamics in several ways including access to prey near colonies during the critical chick-rearing period. This study addresses breeding success in a Barents Sea colony of common guillemots Uria aalge where trophic conditions vary according to changes in the northward transport of warm Atlantic Water. A drift model was used to simulate interannual ... -
The decline of Norwegian kittiwake populations: modelling the role of ocean warming.
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)The black-legged kittiwake Rissa tridactyla is a pelagic seabird whose population has recently declined in most parts of the North Atlantic and which is red-listed in most bordering countries. To investigate a possible cause for this decline, we analysed the population dynamics of 5 kittiwake colonies along the Norwegian coast, ranging from 62° to 71° N, over the last 20 to 35 yr. By quantifying the ... -
Modelled drift patterns of fish larvae link coastal morphology to seabird colony distribution
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-05-13)Colonial breeding is an evolutionary puzzle, as the benefits of breeding in high densities are still not fully explained. Although the dynamics of existing colonies are increasingly understood, few studies have addressed the initial formation of colonies, and empirical tests are rare. Using a high-resolution larval drift model, we here document that the distribution of seabird colonies along the ... -
Prey density in non-breeding areas affects adult survival of black-legged kittiwakes Rissa tridactyla
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014-08-27)In migratory birds, environmental conditions in both breeding and non-breeding areas may affect adult survival rates and hence be significant drivers of demographic processes. In seabirds, poor knowledge of their true distribution outside the breeding season, however, has severely limited such studies. This study explored how annual adult survival rates of black-legged kittiwakes Rissa tridactyla ... -
The stress hormone corticosterone in a marine top predator reflects short-term changes in food availability
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015)In many seabird studies, single annual proxies of prey abundance have been used to explain variability in breeding performance, but much more important is probably the timing of prey availability relative to the breeding season when energy demand is at a maximum. Until now, intraseasonal variation in prey availability has been difficult to quantify in seabirds. Using a state-of-the-art ocean ... -
There is more to climate than the North Atlantic Oscillation: a new perspective from climate dynamics to explain the variability in population growth rates of a long-lived seabird
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-04-29)Predicting the impact of global climate change on the biosphere has become one of the most important efforts in ecology. Ecosystems worldwide are changing rapidly as a consequence of global warming, yet our understanding of the consequences of these changes on populations is limited. The North Atlantic Oscillation (NAO) has been used as a proxy for “climate” in several ecological studies, but this ... -
Tree thinking cannot taken for granted: challenges for teaching phylogenetics
(Journal article; Tidsskriftartikkel; Peer reviewed, 2008-02-05)Tree thinking is an integral part of modern evolutionary biology, and a necessary precondition for phylogenetics and comparative analyses. Tree thinking has during the 20th century largely replaced group thinking, developmental thinking and anthropocentricism in biology. Unfortunately, however, this does not imply that tree thinking can be taken for granted. The findings reported here indicate ...
