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Clint C Muhlfeld

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Much remains unknown about the genetic status and population connectivity of high-elevation and high-latitude freshwater invertebrates, which often persist near snow and ice masses that are disappearing due to climate change. Here we report on the conservation genetics of the meltwater stonefly Lednia tumana (Ricker) of Montana, USA, a cold-water obligate species. We sequenced 1530 bp of mtDNA from 116 L. tumana individuals representing “historic” (>10 yr old) and 2010 populations. The dominant haplotype was common in both time periods, while the second-most-common haplotype was found only in historic samples, having been lost in the interim. The 2010 populations also showed reduced gene and nucleotide diversity...
Climate change may facilitate the expansion of non-native invasive species (NIS) in aquatic and terrestrial systems. However, empirical evidence remains scarce and poorly synthesized at scales necessary for effective management. We conducted a literature synthesis to assess the state of research on the observed and predicted effects of climate change on a suite of 398 aquatic and terrestrial NIS now present in or a major threat to aquatic and terrestrial ecosystems of the Pacific Northwest (PNW), USA and British Columbia. Surprisingly, very few studies (n = 15) have investigated the observed effects of climate change on the distribution, abundance, spread, or impact of the focal NIS, with only five studies focusing...
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To determine minimum coverage of perennial snow and ice cover for Glacier National Park, the minimum extent of glaciers and multi-year snow features were digitized from satellite imagery (10-meter NAPP 2003, NAIP 2005, and NAIP 2013, and 30-cm resolution, multispectral, pansharpened Digital Globe WorldView satellite imagery collected in late summer and fall 2015). Features were digitized in ArcGIS version 10.2 using a Wacom Intuos 4 digitizing tablet. Snow and ice features were classified as glacier, large ice mass, or perennial snow/ice. Glaciers were based on current, named glaciers. Remnant ice features not large enough to be classified as glaciers, but showing evidence of crevasses, were classified as large...
Global climate change is likely to dramatically impact the structure and function of freshwater systems, yet no studies have comprehensively assessed the potential effects of climate change on aquatic ecosystems in the Great Northern Landscape. The continued research described herein aims to build on an existing climate change and transboundary research program to assess the potential hydrologic, geomorphic, and thermal effects on foodwebs (rare and endemic macroinvertebrates), native salmonids (threatened bull trout and westslope cutthroat trout), and lotic habitats in the transboundary (US and Canada) Flathead River system. The project will apply new and existing techniques for combining downscaled and regionalized...
Didymosphenia geminata (didymo) is a freshwater alga native to North America, including Glacier National Park, Montana. It has long been considered a cold-water species, but has recently spread to lower latitudes and warmer waters, and increasingly forms large blooms that cover streambeds. We used a comprehensive monitoring data set from the National Park Service (NPS) and USGS models of stream temperatures to explore the drivers of didymo abundance in Glacier National Park. We estimate that approximately 64% of the stream length in the park contains didymo, with around 5% in a bloom state. Results suggest that didymo abundance likely increased over the study period (2007–2009), with blooms becoming more common....
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