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Predator-prey interactions influence behaviors and life-history evolution for both predator and prey species and also have implications for biodiversity conservation. A fundamental goal of ecology is to clarify mechanisms underlying predator- prey interactions and dynamics. To investigate the role of predator sensory mechanisms in predator-prey interactions, specifically in predator detection of prey, we experimentally evaluated importance of visual and olfactory cues for an apex predator, the coyote (Canis latrans Say, 1823). Unlike similar studies, we examined use of sensory cues in a field setting. We used trail cameras and four replicated treatments--visual only, olfactory only, visual and olfactory combined, and a control--to quantify coyote visitation rates in North American deciduous forests during fall 2016. Coyote visitation was greatest for olfactory-only and visual-only cues, followed by the combined olfactory-visual cue; all cues attracted more coyotes than the control (i.e., olfactory = visual > olfactory-visual > control). Our results suggest this apex predator uses both olfactory and visual cues while foraging for prey. These findings from a field study of free-roaming coyotes increase understanding of predator foraging behavior, predator- prey interactions, and sensory ecology. Our study also suggests future directions for field evaluations of the role of different sensory mechanisms in predator foraging and prey concealment behaviors. Key words: Canis latrans, coyote, foraging ecology, habitat selection, habitat use, olfactory concealment, predator-prey interactions, sensory cues, visual concealment. Les interactions prédateurs-proies influencent les comportements et l'évolution du cycle biologique tant pour les espèces de prédateurs que pour celles de proies et sont également importantes pour la conservation de la biodiversité. La détermination des mécanismes qui sous-tendent les interactions et la dynamique prédateurs-proies constitue un objectif fondamental de l'écologie. Pour examiner le rôle des mécanismes sensoriels des prédateurs dans les interactions prédateurs- proies, plus précisément dans la détection de proies par les prédateurs, nous avons évalué de manière expérimentale l'importance de signaux visuels et olfactifs pour un prédateur de niveau trophique supérieur, le coyote (Canis latrans Say, 1823). Contrairement à d'autres études semblables, nous avons examiné l'utilisation de signaux sensoriels sur le terrain. Nous avons utilisé des caméras de chasse et quatre traitements répliqués--visuel seulement, olfactif seulement, visuel et olfactif combinés et un témoin--pour quantifier la fréquence de visites de coyotes dans des forêts de feuillus d'Amérique du Nord à l'automne 2016. La fréquence des visites de coyotes était la plus grande pour les signaux seulement olfactif et seulement visuel, suivis par les signaux olfactif et visuel combinés; tous les signaux attiraient plus de coyotes que le témoin (c.-à-d., olfactif = visuel > olfactif- visuel > témoin). Nos résultats indiqueraient que ce prédateur de niveau trophique supérieur utilise des signaux olfactifs et visuels dans sa quête de proies. Ces constatations tirées de l'étude sur le terrain de coyotes en liberté accroissent la compréhension du comportement de quête de nourriture des prédateurs, des interactions prédateurs-proies et de l'écologie sensorielle. L'étude suggère également de futures directions pour l'évaluation sur le terrain du rôle de différents mécanismes sensoriels dans les comportements de quête de nourriture des prédateurs et de dissimulation des proies. [Traduit par la Rédaction] Mots-clés : Canis latrans, coyote, écologie de la quête de nourriture, sélection d'habitat, utilisation de l'habitat, dissimulation olfactive, interactions prédateurs-proies, signaux sensoriels, dissimulation visuelle., Introduction Predator-prey interactions are a key class of community interactions that influence ecosystem dynamics (Dulvy et al. 2004; Beauchamp et al. 2007; Ripple and Beschta 2012), drive behavioral and life-history [...]

By the time Charles Darwin landed in Brazil in 1832 while on his voyage on the HMS Beagle, Europeans had known for centuries that the tropics house an extraordinary variety [...]

Plans to triple the area of plantations will not meet 1.5 °C climate goals. New natural forests can, argue Simon L. Lewis, Charlotte E. Wheeler and colleagues. Plans to triple the area of plantations will not meet 1.5 °C climate goals. New natural forests can, argue Simon L. Lewis, Charlotte E. Wheeler and colleagues., Author(s): Simon L. Lewis, Charlotte E. Wheeler, Edward T. A. Mitchard, Alexander Koch Author Affiliations: Restoring natural forests is the best way to remove atmospheric carbon Reforesting of burnt areas [...]

Metabarcoding is a powerful, increasingly popular tool for biodiversity assessment, but it still suffers from some drawbacks (specimen destruction, separation, and size sorting). In the present study, we tested a non-destructive protocol that excludes any sample sorting, where the ethanol used for sample preserving is filtered and DNA is extracted from the filter for subsequent DNA metabarcoding. When tested on macroinvertebrate mock communities, the method was widely successful but was unable to reliably detect mollusc taxa. Three different protocols (no treatment, shaking, and freezing) were successfully applied to increase DNA release to the fixative. The protocols resulted in similar success in taxa detection (6.8-7 taxa) but differences in read numbers assigned to taxa of interest (33.8%-93.7%). In comparison to conventional bulk sample metabarcoding of environmental samples, taxa with pronounced exoskeleton and small-bodied taxa were especially underrepresented in ethanol samples. For EPT (Ephemeroptera, Plecoptera, Trichoptera) taxa, which are important for determining stream ecological status, the methods detected 46 OTUs in common, with only 4 unique to the ethanol samples and 10 to the bulk samples. These results indicate that fixative-based metabarcoding is a non-destructive, time-saving alternative for biodiversity assessments focussing on taxa used for ecological status determination. However, for a comprehensive assessment on total invertebrate biodiversity, the method may not be sufficient, and conventional bulk sample metabarcoding should be applied. Key words: non-destructive, environmental DNA, macroinvertebrates, metabarcoding. Le meta-codage a barres est un outil puissant de plus en plus utilise pour mesurer la biodiversite, mais il presente toujours certains inconvenients (destruction, separation et triage des specimens). Dans le present travail, les auteurs ont explore un protocole non-destructif qui exclut tout triage des echantillons; l'ethanol employe pour preserver l'echantillon est filtre et l'ADN est extrait du filtre pour etre employe subsequemment pour le meta-codage a barres. Lorsque teste sur des communautes simulees de macro-invertebres, la methode s'est largement averee un succes, sans toutefois reussir a detecter de maniere fiable les mollusques. Trois protocoles differents (aucun traitement, agitation et congelation) ont ete appliques pour augmenter la liberation de l'ADN. Ces protocoles ont entraine un succes comparable en matiere de detection de taxons (6,8 a 7 taxons), mais des nombres variables de sequences assignees aux taxons d'interet (33,8 a 93,7 %). Comparativement aux methodes conventionnelles employees sur des echantillons environnementaux, les taxons avec des exosquelettes prononces ou encore de petite taille etaient particulierement sous-representes au sein des echantillons d'ethanol. Pour les taxons EPT (Ephemeroptera, Plecoptera, Trichoptera), lesquels sont importants pour determiner le statut ecologique des ruisseaux, les methodes ont permis de detecter 46 OTU en commun, tandis que 4 etaient uniques aux echantillons d'ethanol et 10 aux echantillons traditionnels en composite. Ces resultats indiquent que la methode de meta-codage a barres faisant appel au fixatif constitue une alternative non-destructive et rapide pour les mesures de la biodiversite portant sur des taxons utilises pour determiner l'etat des ecosystemes. Cependant, pour une evaluation exhaustive de la biodiversite totale, la methode n'est peut-etre pas suffisante et il faudrait employer des methodes conventionnelles d'analyse d'echantillons composites. [Traduit par la Redaction] Mots-cles : non-destructif, ADN environnemental, macro-invertebres, meta-codage a barres., Introduction DNA metabarcoding was developed to improve the efficiency, reliability, and resolution of biodiversity assessments. The technique is based on parallel sequencing of standardised DNA barcode markers. Due to the [...]

Retention harvests may leave retention in aggregations evenly dispersed or in various combinations. Although the relative efficacy of aggregated and dispersed retention for biodiversity conservation is widely debated, there has been little study of combinations. We studied this question relative to saproxylic beetles that initially colonize horizontal and upright coarse woody material (CWM) of white spruce (Picea glauca (Moench) Voss) in boreal mixedwood stands at the Ecosystem Management Emulating Natural Disturbance (EMEND) in northern Alberta 12-13 years after retention prescription. Neither species richness nor emergence of beetles differed among freshly cut bolts exposed as 'horizontal' or 'upright' in retention patches of two sizes (0.20 ha and 0.46 ha) that were surrounded by different levels of dispersed retention (2%, 20%, and 50%). However, species composition in retention patches differed significantly from those in unharvested controls, except in the larger patches surrounded by 50% dispersed retention, although patterns differed among feeding guilds. Both mycetophage and predator assemblages in patches were similar to those in unharvested controls, suggesting that even relatively small patches retain these guilds regardless of the surrounding matrix quality. Because species composition differed between horizontal and upright bolts, an appropriate mix of horizontal and upright CWM may contribute to conservation of saproxylic beetle faunas.Key words: retention forestry, aggregated retention, dispersed retention, biodiversity conservation, saproxylic beetles.Les coupes avec retention conservent des tiges regroupees (bouquets) ou egalement dispersees mais peuvent aussi engendrer diverses combinaisons de ces deux configurations. Bien que l'efficacite relative de la retention regroupee ou dispersee pour la conservation de la biodiversite soit largement debattue, il existe peu d'etudes portant sur la combinaison des deux configurations. Nous avons etudie cette question en lien avec les coleopteres saproxyliques qui colonisent initialement le materiel ligneux grossier (MLG) en position horizontale et verticale de l'epinette blanche (Picea glauca (Moench) Voss). L'etude a ete menee dans des peuplements mixtes boreaux faisant partie du projet Gestion de l'ecosysteme par emulation des perturbations naturelles (EMEND) dans le nord de l'Alberta, 12-13 ans apres une prescription de coupe avec retention. Ni la richesse en especes, ni l'emergence des coleopteres differaient parmi les billes fraichement coupees, exposees en position horizontale ou verticale dans des bouquets de deux tailles (0,20 et 0,46 ha) entoures de differents degres de retention dispersee (2, 20 et 50 %). Cependant, la composition en especes dans les bouquets etait significativement differente de celle des temoins non recoltes, a l'exception des bouquets de plus grandes tailles entoures d'une retention dispersee de 50 %, mais les patrons des guildes alimentaires etaient tout de meme differents. Tant les assemblages mycetophages que les predateurs dans les bouquets etaient semblables a ceux des temoins non recoltes, ce qui indique que meme les bouquets relativement petits conservent ces guildes peu importe la qualite de la matrice environnante. Parce que les billes en position horizontale et verticale avaient une composition en especes differente, un melange approprie de MLG en position horizontale et verticale pourrait contribuer a la conservation de la faune de coleopteres saproxyliques. [Traduit par la Redaction]Mots-cles : foresterie avec retention, retention regroupee, retention dispersee, conservation de la biodiversite, coleopteres saproxyliques., IntroductionBalancing timber harvest and biodiversity conservation is a key objective of modern industrial forestry (Gustafsson et al. 2012; Fedrowitz et al. 2014). Retention harvests were first incorporated into forestry practices, [...]

Decision-makers need input from researchers on issues involving science and society.Decision-makers need input from researchers on issues involving science and society., Author(s): Julia RosenAuthor Affiliations:Help to shape policy with your science A protest in Brussels ahead of the European Union's vote to ban neonicotinoid pesticides in April 2018. [see PDF for [...]

Global transport of organisms by humans provides novel resources to wild species, which often respond maladaptively. Native herbivorous insects have been killed feeding on toxic exotic plants, which acted as 'ecological traps'.sup.1-4. We document a novel 'eco-evolutionary trap' stemming from the opposite effect; that is, high fitness on an exotic resource despite lack of adaptation to it. Plantago lanceolata was introduced to western North America by cattle-ranching. Feeding on this exotic plant released a large, isolated population of the native butterfly Euphydryas editha from a longstanding trade-off between maternal fecundity and offspring mortality. Because of this release--and despite a reduced insect developmental rate when feeding on this exotic--Plantago immediately supported higher larval survival than did the insects' traditional host, Collinsia parviflora.sup.5. Previous work from the 1980s documented an evolving preference for Plantago by ovipositing adults.sup.6. We predicted that if this trend continued the insects could endanger themselves, because the availability of Plantago to butterflies is controlled by humans, who change land management practices faster than butterflies evolve.sup.6. Here we report the fulfilment of this prediction. The butterflies abandoned Collinsia and evolved total dependence on Plantago. The trap was set. In 2005, humans withdrew their cattle, springing the trap. Grasses grew around the Plantago, cooling the thermophilic insects, which then went extinct. This local extinction could have been prevented if the population had retained partial use of Collinsia, which occupied drier microhabitats unaffected by cattle removal. The flush of grasses abated quickly, rendering the meadow once again suitable for Euphydryas feeding on either host, but no butterflies were observed from 2008 to 2012. In 2013-2014, the site was naturally recolonized by Euphydryas feeding exclusively on Collinsia, returning the system to its starting point and setting the stage for a repeat of the anthropogenic evolutionary cycle.Local extinction of the butterfly Euphydryas editha occurred after the population was caught in an eco-evolutionary trap set when the insects evolved unanimous preference for an exotic host, Plantago lanceolata, and sprung when that host became embedded in grasses after humans removed cattle., Author(s): Michael C. Singer [sup.1] [sup.2] , Camille Parmesan [sup.1] [sup.2] [sup.3] Author Affiliations:(1) Biological and Marine Sciences, University of Plymouth, Plymouth, UK(2) Theoretical and Experimental Ecology Station, CNRS, Université [...]