Jessica Allen

(no abstract available)

Species-focused conservation requires a thorough understanding of species’ distributions. Delineating a species’ distribution requires taxonomic knowledge and adequate occurrence data. For plants and fungi, herbaria represent a valuable source of large-scale occurrence data. Advances in digital technology mean that data from many herbarium collections worldwide are now easily accessible. However, species concepts can change over time requiring herbarium records to be re-examined and databases updated, which does not always occur synchronously across all collections. Therefore, non-critical use of these data can promote inaccuracies in understanding species distributions. Taxonomic revisions are common in understudied organisms, such as lichens. Here, we illustrate how changing taxonomy and non-critical acceptance of online data affects our understanding of disjunct distributions, using the lichen Brodoa oroarctica (Krog) Goward as an example. Defining the distribution of the arctic lichen B. oroarctica is confounded by changing taxonomy and uncertainty of herbarium records that pre-date taxonomic revisions. We review the distribution of this species in the literature and in aggregate occurrence databases, and verify herbarium specimens that represent disjunct occurrences in eastern North America to present an updated account of its distribution and frequency in eastern North America. We show that knowledge of changing species taxonomy is essential to depicting accurate species distributions.

The northern bog lemming Synaptomys borealis (NBL) is a rare small mammal that is undergoing a federal Species Status Assessment (SSA) under the US Endangered Species Act. Despite a wide North American distribution, very little is known about NBL dietary or habitat needs, both of which are germane to the resiliency of this species to climate change. To quantify diet composition of NBL in Alaska, we used DNA metabarcoding from 59 archived specimens to describe the taxonomic richness and relative abundance of foods in recent diets. DNA analyses revealed a broad diet composed of at least 110 families and 92 genera of bryophytes (mosses and liverworts), graminoids, fungi, forbs, and woody shrubs. Nine bryophyte genera and Carex sedges composed the largest portions of NBL diets. To quantify habitat preference, we intersected 467 georeferenced occurrence records of NBL in Alaska with remotely sensed land cover classes and used a compositional analysis framework that accounts for the relative abundance of land cover types. We did not detect significant habitat preferences for specific land cover types, although NBL frequently occurred in evergreen forest, woody wetlands, and adjacent to water. Our research highlights the importance of bryophytes, among a high diversity of dietary components, and describes NBL as boreal habitat generalists. Results will inform the current federal SSA by quantifying the extent to which ecological constraints are likely to affect NBL in a rapidly changing boreal environment.

Calicioid lichens and fungi form a diverse polyphyletic group whose species richness is often associated with old-growth forests and ecological continuity. One of the last intact forest landscapes south of the 50th parallel in Québec includes the Ya’nienhonhndeh territory, which has been the focus o…