Environmental DNA (eDNA) assays for single‐ and multi‐species detection show promise for providing standardized assessment methods for diverse taxa, but techniques for evaluating multiple taxonomically divergent assemblages are in their infancy. We evaluated whether microfluidic multiplex metabarcoding on the Fluidigm Access Array™ platform and high‐throughput sequencing could identify diverse stream and riparian assemblages from 48 taxon‐general and taxon‐specific metabarcode primers. eDNA screening was paired with electrofishing along a stream continuum to evaluate congruence between methods. A fish hatchery located midway along the stream continuum provided a dispersal barrier, and a point source for non‐native White Sturgeon (Acipencer transmontanus). Microfluidic metabarcoding had 87% accuracy with respect to electrofishing and detected all 13 species electrofishing observed. Taxon‐specific barcoding primers were more successful than taxon‐general universal metabarcoding primers at classifying sequences to species. Both types of markers detected a transition from downstream sites dominated by multiple fish species, to upstream sites dominated by a single species; however, we failed to detect a complementary transition in amphibian occupancy. White Sturgeon was only detected at the hatchery outflow, indicating eDNA transport was not detectable ~2.4 km from its source. Overall, we identified 878 predicted taxa. Most sequences (50.1%) derived from fish (Actinopteri, Petromyzontidae), oomycetes (21.3%), arthropoda (classes Insecta, Decapoda; 16.5%), and apicomplexan parasites (3.8%). Taxa accounting for ~1% or less of sequences included freshwater red algae, diatoms, amphibians, and beaver. Our work shows that microfluidic metabarcoding can survey multiple phyla per assay, providing fine discrimination required to resolve closely related species, and enable data‐driven prioritization for multiple forest health objectives.
Shorelines in Alaska are changing, with significant consequences for the animals and people in this region. Organizing a series of student-led discussions with community leaders and Alaskan Native elders, Pacific Northwest Research Station scientists Adelaide Johnson and Linda Kruger have identified which coastal resources are of most concern to local communities and how coastal changes may impact these valued resources.
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We quantified the sum of daily mean temperature above 0 °C and modeled incubation duration using water temperature data collected at 12 coho salmon (Oncorhynchus kisutch) spawning sites during two incubation periods with cool, snow dominant conditions and three incubation periods with anomalously warm, rain-transitional conditions, a proxy for a future climate scenario. Warmer water temperatures during warm–rain-transitional winters yielded a 58-day reduction in the median duration of egg incubation; however, the magnitude of change at individual sites varied widely and was controlled by water source. At groundwater-fed sites, temperature variations were strongly attenuated, leading to small interannual differences in incubation duration that were relatively insensitive to short-term changes in air temperature. In contrast, modeled incubation duration was shortened by up to 3 months during warm–rain-transitional winters at precipitation-fed sites. Remarkably, our modeling showed increased uniformity in incubation duration across the landscape during warm–rain-transitional winters. The potential loss of diversity in incubation duration during warmer winters, in isolation, may reduce portfolio effects in this region’s coho salmon population by promoting greater synchronization in the time of spawning.
The U.S. Forest Service and other federal land managers are responsible for maintaining the productivity of aquatic–riparian ecosystems, the associated native biota, and the ecosystem services they provide. These public lands are important sources of water, recreation opportunities, and habitat for a suite of animals and plants, including many that are protected under the Endangered Species Act. To meet these challenges and responsibilities, recent science suggests modifying practices to provide a broader array of habitat, biological conditions, and ecosystem functions than are associated with traditional management approaches. We suggest that by linking approaches based on natural disturbance and portfolio concepts, managers can achieve a robust strategy and desired outcomes more reliably and cost effectively. Locally complex habitat conditions created by natural disturbances provide the template for biological diversity to play out provided enough time. Accordingly, natural disturbance regimes play an important role in creating and sustaining habitat and biological complexities on the landscape, and management actions can emulate natural disturbance processes at appropriate spatial and temporal scales where possible. The portfolio effect (i.e., diversity that mitigates risk) provides justification for promoting connected heterogeneous habitats that reduce the risk of synchronous large–scale population and ecosystem collapse. In this paper, we describe how disturbance and portfolio concepts fit into a broader strategy of conserving ecosystem integrity and dynamism, and provide examples of how these concepts can be used to address a wide range of management concerns. Ultimately, the outcome for populations, habitats, and landscapes depends on how well environmental change is understood, the degree to which change is appropriately addressed by natural resource managers, and on solutions that allow populations and ecosystems to persist in the presence of and be resilient to a growing scope of human influences.
This is a synthesis of our recent article in Biodiversity Conservation written in less technical language for wildlife managers for consideration for publication in the widely read magazine published by The Wildlife Society, "The Wildlife Professional." We introduce a new metric that we derived to batch-assess broad taxonomic groups relative to their climate sensitivity and rarity. We conducted a case study assessment of all fishes, amphibians, and reptiles with native ranges in Oregon, using our new metric. We also analyzed the data from these three taxa to see if it mattered how easily accessible locality data were compiled, by data type, by geographic scope, or by spatial resolution of how a "site" was defined. Our intent was to show how wildlife managers could easily and practically conduct large regional climate sensitivity and rarity assessments of multiple taxa using a common approach, such that cross-taxonomic comparisons could be made. Our results point out species that may have been neglected in earlier assessments of rarity alone. Results are pertinent to state wildlife resource management decisions.