Assessment of methods for estimating wild rabbit population abundance in agricultural landscapes

Various methods have been used to estimate rabbit abundance, but comparisons of standard methods are still lacking, and thus, results remain roughly comparable across studies. Ideally, a method should be applicable over a wide range of situations, such as differing abundances or habitat types. Comparisons of methods are required to evaluate the benefits of each of them, and survey methods should be validated for the conditions in which they will be used. In this study, we compare the performance of direct methods (kilometric abundance index and distance sampling) in two seasons and at two times of day (dusk and night) for estimating wild rabbit abundances in agricultural landscapes. Estimates based on direct methods were highly correlated and detected similar seasonal population changes. Night counts provided better estimates than did dusk counts and exhibited more precision. Results are discussed within the context of rabbit behaviour and their implications for rabbit population surveys.Funding was provided by FEDENCA. ICB was supported by a PhD fellowship from the Spanish Ministry of Science and Innovation. PA is currently enjoying a Juan de la Cierva research contract awarded by the Spanish Ministry of Science and Innovation and is supported by the project CGL2006-09567/BOS.Peer Reviewe

Adaptations of a native Subantarctic flightless fly to dehydration stress: more plastic than we thought? ( Short Communication)

Water conservation is a critical aspect affecting the survival, distribution and abundance of terrestrial arthropods. In this study we investigate mechanisms of dehydration tolerance of the native, flightless fly, Calycopteryx moseleyi, inhabiting contrasting environments at two localities in the Kerguelen Islands. We compare the survival abilities and management of body water content of adult flies from two different ecophenotypes when exposed to conditions of low relative humidity. Our results suggest a broad plasticity in the responses of C. moseleyi to desiccation, showing distinct local adaptations to environmental conditions

Herbivoría de zonas árticas y alpinas en el contexto del cambio global

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Effects of reduced water availability and insecticide on damage caused by cabbage root fly larvae

The incidence of horticultural pests in combination with increased frequency of extreme weather events, like summer drought, can compromise crop production in Nordic agricultural systems during the already short summer growing season. In particular, rootfeeding insects can severely damage plants when combined with water deficits because root herbivores reduce plant water and nutrient uptake (Zvereva & Kozlov 2012). The cabbage root fly Delia radicum (L.) (Diptera: Anthomyiidae) is a major pest of cauliflower Brassica oleracea (L.) (Brassicales: Brassicaceae) crops in Iceland (Halldorsson 1989). Its larvae feed on roots of brassica plants, initially on root hairs and then by tunnelling into the taproot. Cabbage root flies overwinter as pupae in diapause in the soil around brassica plant roots (Bažok et al. 2012). In Iceland, adults emerge in June and females lay eggs between late June and early July (Halldorsson 1989). Eggs are laid on the soil surface around the base of the stems of brassica plants and are relatively resistant to desiccation (Lepage et al. 2012). In contrast, survival of first-instar larvae is compromised at low levels of soil moisture (Lepage et al. 2012). The aim of this study was to investigate the potential effects of reduced water supply on damage by cabbage root fly on cauliflower plants using a field experiment in Iceland. Specifically, we assessed the effect of reduced water supply on larval densities and on early-season growth of cauliflower plants. We expected reduced biomass production in plants that were not treated with insecticides; we hypothesized that this effect would be aggravated during periods of reduced water availability because the water deficit imposed by root damage would be stronger when combined with reduced water supply.Peer Reviewe

From Bare to Birch: Large-Scale Ecosystem Restoration in Iceland

The case of Hekluskógar (meaning “Hekla woodlands”) in South Iceland examines how to transition from barren desertified land to a resilient and healthy woodland that can provide ecosystem services to the people in the area and beyond. The case provides a thorough description and background of the many components involved in the largest reforestation project in Europe as of 2018. The area surrounding Mount Hekla, one of Iceland’s most active volca

What are the effects of herbivore diversity on tundra ecosystems? : A systematic review protocol

Funding Information: The project was funded by the Icelandic Research Fund (Grant Nr. 217754) and the European Union’s Horizon 2020 programme (CHARTER project, Grant Agreement Nr. 869471). Funding for open access publication was provided by the Agricultural University of Iceland. The funding bodies had no influence in the design of the study and collection, analysis and interpretation of data. Funding Information: This study is a contribution of the Herbivory Network (http://herbivory.lbhi.is), a UArctic Thematic Network. Publisher Copyright: © 2022, The Author(s).Background: Changes in the diversity of herbivore communities can strongly influence the functioning of northern ecosystems. Different herbivores have different impacts on ecosystems because of differences in their diets, behaviour and energy requirements. The combined effects of different herbivores can in some cases compensate each other but lead to stronger directional changes elsewhere. However, the diversity of herbivore assemblages has until recently been a largely overlooked dimension of plant–herbivore interactions. Given the ongoing environmental changes in tundra ecosystems, with increased influx of boreal species and changes in the distribution and abundance of arctic herbivores, a better understanding of the consequences of changes in the diversity of herbivore assemblages is needed. This protocol presents the methodology that will be used in a systematic review on the effects of herbivore diversity on different processes, functions and properties of tundra ecosystems. Methods: This systematic review builds on an earlier systematic map on herbivory studies in the Arctic that identified a relatively large number of studies assessing the effects of multiple herbivores. The systematic review will include primary field studies retrieved from databases, search engines and specialist websites, that compare responses of tundra ecosystems to different levels of herbivore diversity, including both vertebrate and invertebrate herbivores. We will use species richness of herbivores or the richness of functional groups of herbivores as a measure of the diversity of the herbivore assemblages. Studies will be screened in three stages: title, abstract and full text, and inclusion will follow clearly identified eligibility criteria, based on their target population, exposure, comparator and study design. The review will cover terrestrial Arctic ecosystems including the forest-tundra ecotone. Potential outcomes will include multiple processes, functions and properties of tundra ecosystems related to primary productivity, nutrient cycling, accumulation and dynamics of nutrient pools, as well as the impacts of herbivores on other organisms. Studies will be critically appraised for validity, and where studies report similar outcomes, meta-analysis will be performed.Peer reviewe

Will borealization of Arctic tundra herbivore communities be driven by climate warming or vegetation change?

Poleward shifts in species distributions are expected and frequently observed with a warming climate. In Arctic ecosystems, the strong warming trends are associated with increasing greenness and shrubification. Vertebrate herbivores have the potential to limit greening and shrub advance and expansion on the tundra, posing the question of whether changes in herbivore communities could partly mediate the impacts of climate warming on Arctic tundra. Therefore, future changes in the herbivore community in the Arctic tundra will depend on whether the community tracks the changing climates directly (i.e. occurs in response to temperature) or indirectly, in response to vegetation changes (which can be modified by trophic interactions). In this study, we used biogeographic and remotely sensed data to quantify spatial variation in vertebrate herbivore communities across the boreal forest and Arctic tundra biomes. We then tested whether present-day herbivore community structure is determined primarily by temperature or vegetation. We demonstrate that vertebrate herbivore communities are significantly more diverse in the boreal forest than in the Arctic tundra in terms of species richness, phylogenetic diversity and functional diversity. A clear shift in community structure was observed at the biome boundary, with stronger northward declines in diversity in the Arctic tundra. Interestingly, important functional traits characterizing the role of herbivores in limiting tundra vegetation change, such as body mass and woody plant feeding, did not show threshold changes across the biome boundary. Temperature was a more important determinant of herbivore community structure across these biomes than vegetation productivity or woody plant cover. Thus, our study does not support the premise that herbivore-driven limitation of Arctic tundra shrubification or greening would limit herbivore community change in the tundra. Instead, borealization of tundra herbivore communities is likely to result from the direct effect of climate warming

The sheep in wolf‘s clothing? Recognizing threats for land degradation in Iceland using state-and-transition models

Land degradation and extensive soil erosion are serious environmental concerns in Iceland. Natural processes associated with a harsh climate and frequent volcanic activity have shaped Icelandic landscapes. However, following human settlement and the introduction of livestock in the 9th century the extent of soil erosion rapidly escalated. Despite increased restoration and afforestation efforts and a considerable reduction in sheep numbers during the late 20th century, many Icelandic rangelands remain in poor condition. A deeper understanding of the ecology of these dynamic landscapes is needed, and state-and-transition models (STMs) can provide a useful conceptual framework. STMs have been developed for ecosystems worldwide to guide research, monitoring and management, but have been used at relatively small spatial scales and have not been extensively applied to high-latitude rangelands. Integrating the best available knowledge, we develop STMs for rangelands in Iceland, where sheep grazing is often regarded as a main driver of degradation. We use STMs at a country-wide scale for three time periods with different historical human influence, from pre-settlement to present days. We also apply our general STM to a case study in the central highlands of Iceland to illustrate the potential application of these models at scales relevant to management. Our STMs identify the set of possible states, transitions and thresholds in these ecosystems and their changes over time, and suggest increasing complexity in recent times. This approach can help identify important knowledge gaps and inform management efforts and monitoring programmes, by identifying realistic and achievable conservation and restoration goals.I. C. B. was supported by a postdoctoral fellowship funded by theIcelandic Research Fund (Rannsóknasjóður, grant 152468‐051) andAXA Research Fund (15‐AXA‐PDOC‐307). D. S. H. recieved supportfrom the Natural Sciences and Engineering Research Council (Canada),and ISJ from the University of Iceland Research Fund

Biometrical analysis reveals major differences between the two subspecies of the European rabbit

The climatic oscillations that have occurred in the last few million years have strongly affected species distribution ranges. Highly divergent genetic lineages arose, some of which correspond to recognized subspecies that currently occupy small geographical areas. Understanding the implications of the genetic differences between these subspecies is crucial for proper conservation of Evolutionarily Significant Units. We use the two European rabbit subspecies, Oryctolagus cuniculus cuniculus and O. c. algirus, in the Iberian Peninsula as a model to investigate the repercussions at the biometric level of their largely recognized genetic differentiation. To accomplish this we analysed the ear and hind foot length, and the body mass of 999 adult rabbits from 27 locations across the distribution range of both subspecies in their native range, the Iberian Peninsula. Our results show biometric differences between the two subspecies, also explained by geographical location and sex, O. c. algirus being lighter and having shorter ear and hind foot lengths. We examine these findings under an evolutionary framework, and discuss their implications for current conservation efforts. Future research should focus on the ecological implications of these biometric differences, namely potential different habitat use and anti-predatory strategies in the species' native range.This study was partially funded by Projects PAI06-170, VP-0119-07,POII09-0099-2557, CGL2009-11665, 2012-30E060, CGL2013-43197, CGL2013-43197-R, FCT research project (PTDC/BIA-EVF/111368/2009), and ‘Genomics Applied to Genetic Resources’ co-funded by North Portugal Regional Operational Programme 2007/2013 (ON.2 – O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF). C.F. was supported by a PhD grant (Ref. SFRH/BD/22084/2005) and a postdoctoral grant (Ref. SFRH/BPD/88643/2012), and J.B.-A. by a postdoctoral grant (Ref. SFRH/BPD/65464/2009) all from the Fundaçao para a Ciência e Tecnologia of the Ministêrio da Ciência, Tecnologia e Ensino Superior, Portuguese government. C.F. is currently supported by a Marie Curie Out going International Fellowship for Career Development (PIOF-GA-2013-621571) within the 7th Framework Programme of the European Union. M.D.-M. is currently funded by Consejería de Economía, Innovación, Ciencia y Empleo of Junta de Andalucía, and the European Union’s SeventhFramework Programme for research, technological development and demonstration under grant agreement 267226. C.A.R.-S. was supported by a doctoral grant from the National Council of Science and Technology of Mexico (CONACyT). P.C.A. was supportedby an FCT sabbatical grant (SFRH/BSAB/1278/2012) and by FLAD (Luso-American Foundation).Peer Reviewe

Linking changes in species composition and biomass in a globally distributed grassland experiment

Global change drivers, such as anthropogenic nutrient inputs, are increasing globally. Nutrient deposition simultaneously alters plant biodiversity, species composition and ecosystem processes like aboveground biomass production. These changes are underpinned by species extinction, colonisation and shifting relative abundance. Here, we use the Price equation to quantify and link the contributions of species that are lost, gained or that persist to change in aboveground biomass in 59 experimental grassland sites. Under ambient (control) conditions, compositional and biomass turnover was high, and losses (i.e. local extinctions) were balanced by gains (i.e. colonisation). Under fertilisation, the decline in species richness resulted from increased species loss and decreases in species gained. Biomass increase under fertilisation resulted mostly from species that persist and to a lesser extent from species gained. Drivers of ecological change can interact relatively independently with diversity, composition and ecosystem processes and functions such as aboveground biomass due to the individual contributions of species lost, gained or persisting.EEA Santa CruzFil: Ladouceur, Emma. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Ladouceur, Emma. Helmholtz Centre for Environmental Research – UFZ. Department of Physiological Diversity; AlemaniaFil: Ladouceur, Emma. University of Leipzig. Department of Biology; AlemaniaFil: Ladouceur, Emma. Martin Luther University Halle-Wittenberg. Institute of Computer Science; AlemaniaFil: Blowes, Shane A. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Blowes, Shane A. Martin Luther University Halle-Wittenberg. Institute of Computer Science; AlemaniaFil: Chase, Jonathan M. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Chase, Jonathan M. Martin Luther University Halle-Wittenberg. Institute of Computer Science; AlemaniaFil: Clark, Adam T. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Clark, Adam T. Helmholtz Centre for Environmental Research – UFZ. Department of Physiological Diversity; AlemaniaFil: Clark, Adam T. Karl-Franzens University of Graz. Institute of Biology; Austria.Fil: Garbowski, Magda. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Garbowski, Magda. Helmholtz Centre for Environmental Research – UFZ. Department of Physiological Diversity; AlemaniaFil: Alberti, Juan. Universidad Nacional de Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Laboratorio de Ecología. Mar del Plata; Argentina.Fil: Alberti, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Arnillas, Carlos Alberto. University of Toronto. Department of Physical and Environmental Sciences; Canadá.Fil: Bakker, Jonathan D. University of Washington. School of Environmental and Forest Sciences; Estados UnidosFil: Barrio, Isabel C. Agricultural University of Iceland. Faculty of Environmental and Forest Sciences; IslandiaFil: Bharath, Siddharth. Atria University; India.Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral; Argentina.Fil: Peri, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Harpole, Stanley. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Harpole, Stanley. Helmholtz Centre for Environmental Research – UFZ. Department of Physiological Diversity; AlemaniaMartin Luther University Halle-Wittenberg. Institute of Computer Science; Alemani