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Epigeous fungal fruiting has important impacts on fungal reproduction and ecosystem function. Forest disturbances, such as timber harvest, impact moisture, host availability, and substrate availability, which in turn may drive changes in fungal fruiting patterns and community structure. We surveyed mushrooms in 0.4 ha patch cuts (18 months post-harvest) and adjacent intact hardwood forest in northern New Hampshire, USA, to document the effects of timber harvest on summer fruiting richness, biomass, diversity, and community structure of ectomycorrhizal, parasitic, and saprobic mushroom taxa. Fungal fruiting richness, diversity, and community heterogeneity were greater in intact forests than patch cuts. Among functional groups, ectomycorrhizal fruiting richness, diversity, and biomass were greater in unharvested areas than in the patch cuts, but parasitic and saprobic fruiting did not differ statistically between the two forest conditions. Our findings suggest that timber harvest simplifies fungal fruiting communities shortly after harvest, in particular triggering declines in ectomycorrhizal taxa which are important symbionts facilitating tree establishment and regeneration. Multi-aged silvicultural practices that maintain mature forest conditions adjacent to and throughout harvested areas through deliberate retention of overstory trees and downed woody material may promote fungal fruiting diversity in regenerating stands. Key words: ectomycorrhizal fungi, epigeous sporocarp, fungal fruiting body, forest disturbance, fungal diversity. La fructification des champignons epiges a des repercussions importantes sur la reproduction des champignons et la fonction de l'ecosysteme. Les perturbations de la foret, telles que la recolte de bois, ont un impact sur l'humidite ainsi que la disponibilite des hotes et du substrat, ce qui en retour peut amener des changements dans les patrons de fructification des champignons et la structure de la communaute. Nous avons inventorie les champignons dans des coupes par trouees de 0,4 ha (18 mois apres la recolte) et dans des forets feuillues adjacentes intactes dans le nord du New Hampshire, aux Etats-Unis, pour documenter les effets de la recolte de bois sur la diversite, la biomasse et la richesse des fructifications durant l'ete ainsi que sur la structure de la communaute des taxons de champignons ectomycorhiziens, parasites et saprobies. La richesse et la diversite des fructifications fongiques ainsi que l'heterogeneite des communautes etaient plus elevees dans les forets intactes que dans les coupes par trouees. Parmi les groupes fonctionnels, la richesse, la diversite et la biomasse des fructifications des champignons ectomycorhiziens etaient plus elevees dans les zones non recoltees que dans les coupes par trouees. Par contre, dans les deux situations la fructification des champignons parasites ou saprobies n'etait pas significativement differente. Nos resultats indiquent que la recolte de bois simplifie les fructifications des communautes fongiques peu de temps apres la recolte, surtout en provoquant le declin des taxons ectomycorhiziens, lesquels sont des symbiotes importants qui facilitent la regeneration et l'etablissement des arbres. Les pratiques sylvicoles inequiennes qui maintiennent les conditions de la foret mature adjacente aux zones recoltees et parmi ces zones par la retention deliberee d'arbres dominants et de materiel ligneux au sol, peuvent promouvoir la diversite des fructifications fongiques dans les peuplements en regeneration. [Traduit par la Redaction] Mots-cles : champignons ectomycorhiziens, sporocarpe epige, fructification fongique, perturbation de la foret, diversite fongique., Introduction Epigeous fungal sporocarps (mushrooms) play a critical role in fungal reproduction (Brown and Casselton 2001) and have secondary impacts on food webs (e.g., Orledge and Reynolds 2005), forest health [...]

Following a resource pulse, animals may finance reproduction by consuming concurrently available resources (income breeding) or by storing resources for future reproduction (capital breeding). Understanding how these reproductive strategies are used is important for determining the ecological mechanisms that structure timing of reproduction and that drive interannual population fluctuations in animals.We gathered a reproductive dataset for five small mammal species over a 12‐year period in Northeastern USA during which six masting events of American beech (Fagus grandifolia) and eastern hemlock (Tsuga canadensis) occurred. Masting created alternate years where seeds were either available late (masting year) or early (cached from the previous year) in the breeding season. The small mammal species differed in reliance on seeds and overwintering strategies. We quantified the diet using stable isotopes and recorded reproduction timing, proportion breeding and litter size in females and testes size in males.Timing of seed availability minimally affected litter size but strongly affected proportion breeding and timing of reproduction. During masting years (late seed availability), a higher proportion of females reproduced, with breeding taking place later in the season (lactation timed with peak seed availability), although the delay was restricted in Napaeozapus insignis, an obligate hibernator. After a fall mast, cached seeds were used as capital in the following spring (early seed availability) to support a litter that, depending on the species, occurred 24–79 days sooner than a mast year. No late‐season reproduction occurred in years with early seed availability except for Myodes gapperi which produced a second litter, likely financed by fungal consumption. Males also showed strong responses to seed availability, mirroring female reproduction with testes size staying constant in years with late seed availability and sharply decreasing over the breeding season in years with early seed availability.Our results highlight that although photoperiod and temperature broadly set bounds of the breeding season in temperate environments, resource availability influences the reproductive strategies that species use, which in turn alters reproductive timing and can drive large inter‐annual population fluctuations. Differences in overwintering strategies and diet may further modulate reproductive timing and output relative to resource pulses. [ABSTRACT FROM AUTHOR]

Home range is shaped by an individual's interactions with the environment and conspecifics, and both size and placement may vary in response to population fluctuations. The method used to collect locational data may also affect home-range estimates. We examined the effect of density, sex, and field method on home range of southern red-backed voles (Myodes gapperi (Vigors, 1830)) inhabiting eastern hemlock (Tsuga canadensis (L.) Carriere) forests. Twelve mark-recapture grids were used to census M. gapperi from 2014 to 2017. In 2017, individuals were radio-collared. Home-range size, core-area size, and shared space were calculated using kernel density estimators from both mark-recapture and radiotelemetry data. Density effects on home range and core area were analyzed and differences between sex and field method were compared. We found (i) density did not affect home-range size, (ii) male home range was larger than female home range, (iii) females shared space more frequently and to a greater extent with males than other females, and (iv) home-range estimates were not significantly different between mark-recapture and radiotelemetry. Male home range, however, was larger under radiotelemetry and may reflect a truncation effect when mark-recapture grid size is smaller than male home range. Key words: core area, mark-recapture, Myodes gapperi, northern forests, radiotelemetry, rodent, southern red-backed vole, space use. Le domaine vital est module par les interactions de l'individu avec le milieu et ses congeneres, et tant ses dimensions que son emplacement peuvent varier en reponse aux fluctuations demographiques. La methode employee pour recueillir des donnees de positionnement peut egalement avoir une incidence sur les estimations de parametres du domaine vital. Nous avons examine l'effet de la densite, du sexe et de la methode d'etude de terrain sur le domaine vital de campagnols de Gapper (Myodes gapperi (Vigors, 1830)) dans des forets de pruches du Canada (Tsuga canadensis (L.) Carriere). Douze grilles de marquage-recapture ont ete utilisees pour recenser les campagnols de Gapper de 2014 a 2017. En 2017, des individus ont ete dotes de colliers emetteurs. La taille du domaine vital, la taille de l'aire principale et l'espace partage ont ete calcules en utilisant des estimateurs de la densite de noyaux obtenus des donnees de marquage-recapture et de radiotelemetrie. Les effets de la densite sur la taille du domaine vital et de l'aire principale ont ete analyses et les differences entre les sexes et les methodes de terrain ont ete comparees. Nous avons constate que (i) la densite n'avait pas d'incidence sur la taille du domaine vital, (ii) les domaines vitaux des males etaient plus grands que ceux des femelles, (iii) les femelles partageaient l'espace plus frequemment et dans une plus grande mesure avec des males qu'avec d'autres femelles et (iv) les estimations de parametres du domaine vital obtenues par marquage-recapture et par radiotelemetrie n'etaient pas significativement differentes. Le domaine vital des males estime par radiotelemetrie etait toutefois plus grand, ce qui pourrait refleter un effet de troncation si la grille de marquage-recapture est plus petite que le domaine vital des males. [Traduit par la Redaction] Mots-cles : aire principale, marquage-recapture, Myodes gapperi, forets septentrionales, radiotelemetrie, rongeur, campagnol de Gapper, utilisation de l'espace., Introduction An individual's home range represents the space that they use and reflects a number of important ecological processes and behaviors. The placement and size of the home range is [...]

Here we present the results of taxonomic and systematic study of the rare truffle-forming genera Destuntzia and Kjeldsenia. Truffle-forming fungi are difficult to study due to their reduced morphological features and their cryptic, hypogeous fruiting habits. The rare occurrence of Destuntzia and Kjeldsenia further compounds these difficulties due to the lack of adequate material for study. Recent forays in North Carolina and Tennessee recovered new specimens of another rarely collected fungus, Octaviania purpurea. Morphological and phylogenetic analysis revealed that Octaviania purpurea is a member of the genus Destuntzia, and this led us to reevaluate the taxonomic status and systematic relationships of other Destuntzia species. We performed a multilocus phylogenetic analysis of Destuntzia specimens deposited in public fungaria, including all available type material, and environmental sequences from animal scat and soil. Our analyses indicate that Destuntzia is a member of the family Claustulaceae within the order Phallales and is a close relative of Kjeldsenia. Results of our phylogenetic analysis infer that three species originally described in the genus Destuntzia are members of the genus Kjeldsenia. We propose three new combinations in Kjeldsenia to accommodate these species as well as a new combination in Destuntzia to accommodate Octaviania purpurea. We also describe a new genus in Claustulaceae, Hosakaea, to accommodate a closely affiliated species, Octaviania violascens. Finally, we transfer the genus Destunzia into the family Claustulaceae and emend the description of the family. The newly proposed combinations in Destuntzia and Kjeldsenia significantly expand the known geographic ranges of both genera. The data from metabarcode analysis of scat and soil also reveal several additional undescribed species that expand these ranges well beyond those suggested by basidiomata collections. Systematic placement of Destuntzia in the saprotrophic order Phallales suggests that this genus is not ectomycorrhizal, and the ecological implications of this systematic revision are discussed. [ABSTRACT FROM AUTHOR]

Robustly quantifying dietary resource use and trophic position using stable isotopes requires accurate trophic discrimination factors (TDF; Δ13C and Δ15N for carbon and nitrogen, respectively), defined as the isotopic difference between consumer and diet. Early TDF studies converged on values of around 1.0‰ for Δ13C and 3.4‰ for Δ15N but more recent work indicates that TDF values may be more nuanced, depending on taxa, tissues, trophic level and diets. Yet, the relative importance of these factors remains unclear.Focusing on vertebrates (birds, fish, herptiles and mammals), we conducted a literature review of 279 studies that estimated TDF values and used a Bayesian framework to determine how tissue type, trophic level and diet source influence variation in Δ13C and Δ15N. Additionally, we reviewed 358 trophic ecology studies to determine if studies accounted for these factors during their TDF selection process.For Δ13C, vertebrates showed consistent patterns among tissue types (likely influenced by amino acid composition) and between trophic levels and diet sources (likely a result of dietary protein content and metabolic routing). Comparatively, for Δ15N, vertebrates showed considerable variation among tissue types and trophic levels, likely due to differences in tissue synthesis and physiological capabilities. Overall, Δ13C ranged from −5.1‰ to 9.1‰ and Δ15N from −3.3‰ to 9.7‰, underscoring that 1.0‰ for Δ13C and 3.4‰ for Δ15N are not universally appropriate. Moreover, both Δ13C and Δ15N varied by more than 9‰ within a single species and tissue type, demonstrating that using TDF values from the same, or similar, species may not be appropriate if diet and trophic level are not considered.Despite the importance of diet source on TDF values, most trophic ecology studies did not account for it. Further, most fish studies relied on literature review values that failed to account for tissue type, trophic level and diet source. To aid ecologists in diet and trophic assessments of vertebrates, we used our meta‐analysis to model taxon‐specific TDF estimates (mean ± SD) for each tissue type, trophic level and diet source combination. These more refined TDF values should improve ecological assessments that use stable isotopes. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Stable isotope analysis is increasingly being used to assess diet and trophic positions of animals. Such assessments require estimates of trophic discrimination factors (TDFs)—offset between the isotopic composition of diet and animal tissues—with imprecise applications of TDFs leading to biased conclusions in resource use. Because TDFs are unavailable for most species, ecologists often apply values from taxonomically similar species or use trophic step increases of approximately 1‰ for carbon (TDF‐δ13C) and 3‰ for nitrogen (TDF‐δ15N). Such practices may yield inaccuracies since TDFs vary greatly, even within a species. To better understand the factors that influence TDFs, we conducted a meta‐analysis of TDF‐δ13C and TDF‐δ15N for mammals and quantified variation in relation to consumer type (herbivore, omnivore, carnivore) and diet source (C3‐based, C4‐based, marine‐based, mixture). Additionally, to guide TDF choice, we used an isotopic data set of small mammal tissues and diet items to assess how predicted dietary contributions vary with TDFs estimated using (1) taxonomic relatedness, (2) consumer type and diet source, or (3) values derived from wild animals eating natural diets. Our meta‐analysis revealed that metabolic routing and interactions between consumer class, dietary source, and the protein versus energy content of diets best explained variation in TDF‐δ13C values (−1.5‰ to 7.3‰), whereas consumer class best explained variation in TDF‐δ15N values (−0.5‰ to 7.1‰). Our test of methods to estimate TDFs indicated that ecologists should avoid relying on taxonomic relatedness when selecting TDF‐δ13C because mixed‐diet lab studies may produce misleading results for herbivores and omnivores. Additionally, field‐derived estimates could help fill TDF gaps where diets within a consumer class are absent. Overall, we suggest that using standard TDF trophic step values should be abandoned, because feeding studies are often poor proxies for natural diets, particularly for herbivores and omnivores. Instead, we make recommendations on how to select TDFs, along with a range of TDF‐δ13C and TDF‐δ15N values depending on diet source, consumer class, and tissue type. Use of these more refined recommendations and TDF values in isotopic assessments will improve estimates of diets and trophic interactions in natural systems, leading to a better understanding of ecological interactions and communities. [ABSTRACT FROM AUTHOR]

Speciation among many animals was rapid through the Pleistocene, impacted by climate and periodic isolation and reconnection. As such, species limits among often morphologically cryptic lineages may remain unresolved despite clear mitogenomic partitioning. Accumulating evidence from phylogeographical studies is revealing congruent regional differentiation of lineages across taxonomic groups that share ecological and evolutionary traits. Here, we analyse multiple DNA loci and morphology to resolve the geography and timeframe associated with evolutionary history of North American pygmy shrews (genus Sorex). We then assess lineage diversification among three co-distributed shrew complexes using phylogenetic and approximate Bayesian computation approaches to test a hypothesis of spatial congruence but temporal incongruence of species formation on a continental scale. Our results indicate consistency in regional lineage distributions, partial congruence of the sequence of divergence, and strong but not definitive support for temporal incongruence, suggesting that successive glacial cycles initiated the process of diversification repeatedly through the Pleistocene. Our results emphasize a continuing need for greater genomic coverage in comparative phylogeography, with persistent challenges. We recognize distinct eastern (Sorex hoyi Baird, 1857) and western (Sorex eximius Osgood, 1901) species of pygmy shrew based on available evidence, but discuss issues with taxonomic designations considering the continuum of speciation throughout the boreal biome. [ABSTRACT FROM AUTHOR]

In the face of the growing global biodiversity crisis, we must critically examine factors driving patterns in research to identify knowledge gaps, guide future funding and inform conservation policies and actions. In this article, we reviewed the literature on terrestrial mammals in the contiguous United States to evaluate which factors influence the number of publications for over 300 species and to identify trends in publication rates during the past 50 years. We expected larger body mass, broader geographic range, more years since a species was described, and higher relative abundance to correspond with an increase in the number of publications about a species, and that conservation status and taxonomic order would also affect the number of publications. We found that publications focussed on species that were larger, widespread, described longer ago and at a higher relative abundance. There were no clear trends in research due to a species conservation status, and research effort was not consistent among orders over time. We advocate for changes in requirements for professional advancement, shifts in the publication process and focus, and novel allocations of research funding. [ABSTRACT FROM AUTHOR]

Small-eared shrews (Mammalia, Soricidae) of the New World genus Cryptotis are distributed from eastern North America to the northern Andes of South America. One well-defined clade in this genus is the Central American Cryptotis mexicana group, whose members are set off from other species in the genus by their variably broader fore feet and more elongate and broadened fore claws. Two species in the C. mexicana group, Cryptotis goodwini Jackson and Cryptotis griseoventris Jackson, inhabit highlands in Guatemala and southern Mexico and are presumed to be sister species whose primary distinguishing feature is the larger body size of C. goodwini. To better characterize these species and confirm the identification of recently-collected specimens, we obtained digital X-ray images of the manus from large series of dried skins of both species. Measurements of the metacarpals and phalanges successfully separated most specimens of C. goodwini and C. griseoventris. These measurements also show that the fore feet of C. griseoventris from Chiapas, Mexico, are morphologically distinct from those of members of the species inhabiting Guatemala. Univariate, bivariate, and multivariate analyses indicate that fore foot characters are more conservative within species of the C. mexicana group than are cranio-mandibular characters. Patterns of evolution of fore foot characters that superficially appear to be linear gradations are actually more complex, illustrating individual evolutionary trajectories. No claim to original US government works. Journal compilation © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99, 118–134. [ABSTRACT FROM AUTHOR]