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Background: Bioblitzes are a tool for the rapid appraisal of biodiversity and are particularly useful in remote and understudied regions and for understudied taxa. Lichens are an example of an often overlooked group, despite being widespread in virtually all terrestrial ecosystems and having many important ecological functions. New information: We report the lichens and allied fungi collected during the 2018 terrestrial bioblitz conducted on Calvert Island on the Central Coast of British Columbia, Canada. We identified 449 specimens belonging to 189 species in 85 genera, increasing the total number of species known from Calvert Island to 194, and generated Internal Transcribed Spacer (ITS) sequences for 215 specimens from 121 species. Bryoria furcellata, Chaenothecopsis lecanactidis and C. nigripunctata were collected for the first time in British Columbia. We also found Pseudocyphellaria rainierensis, which is listed as Special Concern on the federal Species at Risk Act, and other rarely reported species in British Columbia including Opegrapha sphaerophoricola, Protomicarea limosa, Raesaenenia huuskonenii and Sarea difformis. We demonstrate that DNA barcoding improves the scope and accuracy of expert-led bioblitzes by facilitating the detection of cryptic species and allowing for consistent identification of chemically and morphologically overlapping taxa. Despite the spatial and temporal limitations of our study, the results highlight the value of intact forest ecosystems on the Central Coast of British Columbia for lichen biodiversity, education and conservation. [ABSTRACT FROM AUTHOR]

Aim: Species distributions across islands are shaped by dispersal limitations, environmental filters and biotic interactions but the relative influence of each of these processes has rarely been assessed. Here, we examine the relative contributions of island characteristics, marine subsidies, species traits, and species interactions on avian community composition. Location: Central Coast region of British Columbia, Canada. Taxon: Terrestrial breeding birds. Methods: We observed 3610 individuals of 32 bird species on 89 islands that spanned multiple orders of magnitude in area (0.0002–3 km2). We fit a spatially explicit joint species distribution model to estimate the relative contributions of island physical characteristics, island‐specific inputs of marine subsidies, species' traits, and biotic interactions on species distributions. Biogeographic characteristics included island area, isolation, and habitat heterogeneity, while marine influence was represented by forest‐edge soil δ15N, wrack biomass, shoreline substrate, and distance to shore. This approach also allowed us to estimate how much variation in distributions resulted from species' biological traits (i.e. body mass, feeding guild, feeding height, and nesting height). Results: Bird species distributions were determined almost equivalently by island biogeographic characteristics (23.5% of variation explained) and marine influence (24.8%). We detected variation in species‐specific responses to both island biogeographic characteristics and marine influence, but no significant effect of any biological trait examined. Additionally, we found evidence that habitat preferences were a more important driver than competitive interactions. Main Conclusions: Although most island biogeographic studies focus only on islands' physical characteristics, we found evidence for an equivalent role of marine subsidy in structuring island bird communities. Our study suggests that for small islands, disentangling the effects of island biogeographic characteristics, marine inputs, and biotic interactions is a useful next step in understanding species distributions. [ABSTRACT FROM AUTHOR]

The exponential growth and interest in community science programs is producing staggering amounts of biodiversity data across broad temporal and spatial scales. Large community science datasets such as iNaturalist and eBird are allowing ecologists and conservation biologists to answer novel questions that were not possible before. However, the opportunistic nature of many of these enormous datasets leads to biases. Spatial bias is a common problem, where observations are biased towards points of access like roads and trails. iNaturalist–a popular biodiversity community science platform–exhibits strong spatial biases, but it is unclear how these biases affect the quality of biodiversity data collected. Thus, we tested whether fine-scale spatial bias due to sampling from trails affects taxonomic richness estimates. We compared timed transects with experienced iNaturalist observers on and off trails in British Columbia, Canada. Using generalized linear mixed models, we found higher overall taxonomic richness on trails than off trails. In addition, we found more exotic as well as native taxa on trails than off trails. There was no difference between on and off trail observations for species that are rarely observed. Thus, fine-scale spatial bias from trails does not reduce the quality of biodiversity measurements, a promising result for those interested in using iNaturalist data for research and conservation management. [ABSTRACT FROM AUTHOR]

Biodiversity community science projects are growing rapidly in popularity. The enormous amounts of data generated by these programs are transforming how we conduct ecological research and conservation management. However, as with other biodiversity surveys, community science datasets suffer from biases in time and locations of observations. To better use these data, we modeled the spatial biases present in the popular community science platform, iNaturalist. iNaturalist uses crowdsourcing to collect georeferenced and time‐stamped observations of all taxa worldwide. With its wealth of biodiversity data, iNaturalist is now being used to answer a broad range of questions in ecology and conservation, but little is known about the platform's spatial biases. We focus on the more than 1.75 million iNaturalist observations available (as of December 2021) from British Columbia, Canada, a region with a strong community science presence and diversity of ecosystems. Using machine learning and species distribution modeling, we examined which landscape factors (e.g., protected areas, roads, human population density, habitat zones, elevation) were most important in determining where observations are taken, and we created a predicted probability map revealing how likely different regions are to be sampled by community scientists. We found strong road biases for observations in iNaturalist, with over 94% of observations within 1 km of roads. In addition, human population density and broad habitat ecosystem zones played a large role in predicting where iNaturalist observations occur across the landscape. These methods demonstrate tools for modeling the effects of spatial biases in large opportunistic datasets that can then be used to produce more accurate species distribution and biodiversity models from community science data. [ABSTRACT FROM AUTHOR]

We examined the factors structuring bird communities across a complex subarctic treeline in the Mealy Mountains, Labrador, Canada. Using point counts of bird abundance in 2007 and 2008, we show that changes in vegetation driven by elevation are strongly correlated with avian community structure in this treeline ecotone system. Overall, avian diversity was higher in the forest compared with other habitat classes (krummholz, deciduous shrub, and alpine). There were strong correlations between avian diversity and vegetation richness, as well as structure, among and within habitat class in 2008. Numerous habitat types (subset of habitat class) were correlated with avian composition, although some species were clearly habitat generalists. Contrary to expectation, avian species composition was associated with physiognomy (vegetation structure) in alpine and deciduous shrub, and with either physiognomy or floristics (vegetation species composition) in krummholz and forest. Given the strong impact of elevation on vegetation and the demonstrated influence on bird communities, we note that for bird species whose near-southernmost populations are found in the Mealy Mountains, climate change is likely to have a strong negative effect if alpine tundra habitat is lost. Furthermore, forest bird species are likely to benefit from the increased tree cover as treeline moves poleward and upward. Key words: treeline, avian species richness, vegetation volume, forest-tundra ecotone, plant community composition, boreal forest, Labrador. Nous avons examine les facteurs qui structurent les communautes d'oiseaux de part et d'autre d'une limite des arbres subarctique complexe dans les montagnes Mealy (Labrador, Canada). En utilisant des denombrements ponctuels de l'abondance d'oiseaux en 2007 et 2008, nous demontrons que les changements de la vegetation associes a l'altitude sont fortement correles a la structure de la communaute d'oiseaux dans ce systeme d'ecotone de limite des arbres. Globalement, la diversite des oiseaux etait plus elevee dans la foret que dans les autres classes d'habitat (krummholz, arbustes feuillus et alpin). Il y avait de fortes correlations entre la diversite des oiseaux et la richesse de la vegetation, ainsi qu'avec la structure, entre les classes d'habitat et au sein de celles-ci en 2008. De nombreux types d'habitat (sous-ensembles des classes d'habitat) etaient correles avec la composition d'oiseaux, bien qu'il soit clair que certaines especes sont des generalistes en ce qui concerne l'habitat. Contrairement aux predictions, la composition des especes d'oiseaux etait associee a la physionomie de la vegetation dans les habitats alpins et d'arbustes feuillus et soit a la physionomie de la vegetation ou a la floristique (composition specifique de la vegetation) dans les habitats de krummholz et forestiers. Etant donne la forte incidence de l'altitude sur la vegetation et l'influence demontree sur les communautes d'oiseaux, nous notons que les changements climatiques auront vraisemblablement un fort effet negatif sur les especes d'oiseaux dont les populations les presque plus au sud se trouvent dans les montagnes Mealy, si l'habitat de toundra alpine disparait. En outre, les especes forestieres d'oiseaux profiteraient vraisemblablement du couvert arbore accru decoulant du deplacement de la limite des arbres vers le pole et vers le haut. [Traduit par la Redaction] Mots-cles: limite des arbres, richesse specifique des oiseaux, volume de la vegetation, ecotone foret-toundra, composition de la communaute de plantes, foret boreale, Labrador., Introduction Ecotones have been extensively studied in large part because of the significant influence they have on biodiversity (Risser 1995; Payette et al. 2001; Harper et al. 2005). This increase [...]

Although many studies have focused on factors influencing treeline advance with climate change, less consideration has been given to potential changes in tree spatial pattern across the forest-tundra ecotone. We investigated trends in spatial pattern across the forest-tundra ecotone and geographical variation in the Yukon, Manitoba, and Labrador, Canada. Tree cover was measured in contiguous quadrats along transects up to 100 m long located in Forest, Ecotone, and Tundra sections across the forest-tundra transition. Spatial patterns were analyzed using new local variance to estimate patch size and wavelet analysis to determine the scale and amount of aggregation. Compared with the Forest, tree cover in the Ecotone was less aggregated at most sites, with fewer smaller patches of trees. We found evidence that shorter trees may be clumped at some sites, perhaps due to shelter from the wind, and we found little support for regular spacing that would indicate competition. With climate change, trees in the Ecotone will likely become more aggregated as patches enlarge and new patches establish. However, results were site-specific, varying with aspect and the presence of krummholz (stunted trees); therefore, strategies for adaptation of communities to climate change in Canada's subarctic forest would need to reflect these differences. Resume: Alors que plusieurs etudes ont mis l'accent sur les facteurs qui influencent la progression de la limite des arbres due aux changements climatiques, peu d'attention a ete accordee aux changements potentiels du patron de repartition spatiale des arbres dans l'ecotone entre la foret et la toundra. Nous avons etudie les changements de la repartition spatiale dans l'ecotone entre la foret et la toundra de meme que sa variation geographique au Yukon, au Manitoba et au Labrador, au Canada. Le couvert forestier a ete mesure dans des quadrats contigus etablis le long de transects pouvant atteindre 100 m de longueur et situes dans les sections de foret, d'ecotone et de toundra dans la zone de transition entre la foret et la toundra. Les patrons spatiaux ont ete analyses avec les methodes de la nouvelle variance locale pour estimer la taille des ilots de foret et avec l'analyse par ondelettes pour determiner l'echelle et le degre d'agregation. Comparativement a la foret, le couvert forestier de l'ecotone etait moins groupe dans la plupart des stations, ce qui s'est traduit par des ilots de foret plus petits et moins nombreux. Nous avons trouve des preuves que les petits arbres peuvent etre regroupes dans certaines stations, probablement pour se proteger du vent, et nous avons trouve peu de signes d'espacement regulier qui auraient indique la presence de competition. Avec les changements climatiques, les arbres etablis dans l'ecotone se regrouperont probablement davantage par l'agrandissement des ilots et par l'etablissement de nouveaux ilots. Cependant, ces resultats sont specifiques aux stations puisqu'ils varient selon leur orientation et en fonction de la presence de krummholz (arbres prostres). Ainsi, les strategies d'adaptation des communautes aux changements climatiques dans la foret subarctique canadienne devraient refleter ces differences. [Traduit par la Redaction], Introduction Increases in global temperature associated with climate change have caused range shifts in a wide array of taxa (Parmesan 2006; Woodall et al. 2009; Harsch et al. 2009). At [...]

Based on records dating from 1859 to 2021, we provide an overview of the marine animal diversity reported for Galiano Island, British Columbia, Canada. More than 650 taxa are represented by 20,000 species occurrence records in this curated dataset, which includes dive records documented through the Pacific Marine Life Surveys, museum voucher specimens, ecological data and crowd-sourced observations from the BC Cetacean Sightings Network and iNaturalist. [ABSTRACT FROM AUTHOR]