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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2024

Abstract

The moose (Alces alces) is a large-bodied, ruminant herbivore inhabiting temperate and boreal forests, where their foraging can profoundly influence ecological processes. In intensively managed landscapes, such as large parts of Scandinavia, browsing by moose can also affect human economic interests, such as commercial forestry. Deciphering the nutritional underpinnings of the moose’ foraging choices is therefore in the interest of both wildlife ecology and forest management. In this talk I will summarise findings from several studies from Scandinavia in which we have used the nutritional geometry framework to study moose foraging behavior. First, a small feeding experiment with captive moose indicated that their food choice was not governed by energy maximization as previously postulated. Instead the moose appeared to combine food to reach a target macronutritional balance. We later confirmed this pattern of macronutrient balancing by analysing rumen content (by wet chemistry and NIRS) and faeces (indirectly via by DNA metabarcoding) from a large number of wild moose during wintertime across Sweden. The moose’ tendency to maintain a stable balance between protein and non-structural carbohydrates was most recently confirmed by a detailed study of moose summer time in Norway, using camera collars and plant collections. These studies on the Scandinavian moose have also revealed patterns of complementarity, compensatory intake, linkages to damage and fitness, and valuable information about key forage plant species, and thereby help to improve our understanding of nutritional ecology.

Abstract

Climate change causes far-reaching disruption in nature, where tolerance thresholds already have been exceeded for some plants and animals. In the short-term, deer may respond to climate through individual physiological and behavioral responses. Over time, individual responses can aggregate to the population level and ultimately lead to evolutionary adaptations. Because responses by deer to climate change may take many paths - both positive and negative - it is generally difficult to predict outcomes. Here we take the first step to understanding these complexities by systematically synthesizing the literature (published 2000-2022) regarding direct effects of temperature, rainfall and snow on deer inhabiting boreal and temperate regions of the northern hemisphere. Our review (based on N= 219 papers) shows that while many deer populations will likely benefit from warmer winters, hotter and drier summers may exceed their physiological tolerances, causing northwards shifts in distributional ranges. We found support for deer expressing both phenotypic and behavioral plasticity in response to climate variability at different temporal and spatial scales. We identified 20 general patterns, among which some illustrate antagonistic pathways, suggesting that detrimental effects will cancel out some of the benefits of climate change. Our findings highlight the importance of local variables for any predictions of future responses by a given deer population. We identified several knowledge gaps, such as studies regarding the potential impact on these animals of extreme weather events, snow type and wetter autumns.

Abstract

Insight from new technology in rangeland grazing systems Inger Hansen, Lise Grøva, Michael Angeloff and Oddbjørn Kaasa Although digital technologies and innovations are increasingly being adopted and accepted in intensive livestock systems, they are poorly developed and implemented in extensive livestock farming systems. On-animal sensors have potential to remotely monitor and identify changes in animal behaviour, such as illness, accidents or depredation. Real time monitoring of livestock may allow farmers and ranchers to respond more rapidly when animals become ill, and by this ensure both production and welfare With the rapid increase in new data from digital technologies from livestock rangeland grazing systems, there is a need to explore the potential for new knowledge and new tools that these data may provide. The potential lies in multisource data analysis to generate new insight on sheep behaviour, interactions and possible criteria for Early Warning Systems (EWS). EWS is in high demand by farmers, authorities and all stakeholders to ensure the sustainable management of our rangeland grazing resources. In Norway we have now started a pilot work to integrate data from GPS tracking collars on free ranging sheep with individual sheep health and production data sources, as well as vegetation maps, weather conditions, human activity and predator killings. Since 2015, Meråker grazing group, consisting of 25 sheep farmers, have used GPS tracking collars on about 2000 ewes from June to September. The data set consists of more than 9 million positions, allowing analysis of the sheep's movement related to numerous environmental and production factors. Integration of these position data with production-, health-, large carnivores- and other explanatory variables, and analysis of these multisource data, has potential to be a game changer for rangeland grazing systems. This presentation will highlight the the potiential for new insight in these farming systems.

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Abstract

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Abstract

In Europe, over a third of the agricultural area is grass meadows used for livestock grazing and fodder production. Grass meadows provide a food source for wild ungulates causing human-wildlife conflicts due to forage removal. Few experimental studies have quantified biomass loss with enough replicates to determine how surrounding environments influences level of biomass removal. Using an exclosure experiment on 57 grassland meadows over five years at the northwest coast of Norway covering 10 650 km2, we quantified biomass removal by red deer (Cervus elaphus L.) and how environmental factors impacted biomass loss (Study 1). Furthermore, we examined development of biomass loss and crude protein concentration in five fields throughout the growing season (Study 2). The average predicted biomass loss to red deer grazing was 16% for the first harvest, and 7.3% for the second harvest (Study 1). Biomass loss increased with red deer density from 0% at the lowest density (0.6 red deer harvested/km2) to 31% at the highest density (4 red deer harvested/km2). Biomass loss increased from 12% to 32.8% as terrain ruggedness index (TRI) rose from 2.1 to 7.1. Absolute biomass loss increased towards time of grass harvest (Study 2). Crude protein concentration was higher in unfenced plots during the period before first harvest, but not between first and second harvest (Study 2). The quantification of biomass removal at a large spatial scale over several years in this study provides a better understanding of factors causing variation in losses.