We evaluated commonly used methods for monitoring stream restorations to inform and improve restoration monitoring and evaluation, using a headwater stream in the Oregon Coast Range as a case-study example. In-stream restoration projects are seldom monitored both pre- and post-restoration. In addition, frequently used low-cost methods may not provide sufficient data to effectively assess trends in stream temperature. Here, we examined what can be learned from temperature loggers installed in the same locations over multiple years in a restored stream. In-stream structures were installed between 2007 and 2011 along a 10-km length of South Sister Creek, Oregon for the purpose of enhancing in-stream habitat. Summer stream temperature data were collected using Hobo Pro-V temperature-logging thermistors at four locations in 2006, prior to restoration, as well as in 2012 and 2013. In 2013, additional temperature loggers were placed within 80 m of the four original loggers to investigate within-reach variability. Although median stream temperatures were highest in 2013 at all four multi-year sites, 7-day maximum temperatures were 4 to 5 °C cooler in post-treatment years than in 2006. Inter-annual variability in stream temperature was more closely linked to inter-annual variability in air temperature and solar radiation than presence of in-stream structures. Thermal heterogeneity was greater in reaches with deeper pools than in bedrock-dominated reaches. Although in-stream structures can create cool microhabitats, they have little influence on mean stream temperature. Longer pre-restoration monitoring and sensor deployment in more varied in-stream habitats would improve our ability to evaluate restoration impacts.

The Chehalis River is a coastal river in southwestern Washington State where decision makers are considering options to reduce flood damage and improve freshwater habitats. This study focused on the mainstem river above and below the location of a potential dam, one of the flood-reduction options being considered. Our objectives were to describe spatial patterns of fish species, physical habitat, and stream temperature, and identify associations between fish species and the physical environment at two spatial scales. Data were collected in spatially continuous reaches following a “riverscape” approach, and patterns in the data were described using three different ordination techniques. Most of the variation in fish species composition occurred at the sub-basin scale (entire study area), with additional but minor patterns at the reach (1-km) scale. At the sub-basin scale, fish species composition was organized in an upstream (salmonid) to downstream (cyprinid) replacement pattern and was best explained by the combination of river location, habitat, and temperature. At the reach scale, physical habitat and stream temperature differentiated juvenile trout versus coho salmon in the salmonid-dominated upstream extent of our study area, and dace versus shiner in the cyprinid-dominated downstream extent. We conclude that salmon and steelhead are particularly vulnerable to habitat loss upstream of the proposed dam because they disproportionately use this area as summer rearing habitat. Protection and restoration of headwater areas, such as our study area in the Chehalis River, will be critical to support salmonid populations into the future.

Sculpins (family Cottidae) are a group of small nongame fishes, native to Idaho's colder streams, and have value for biodiversity and as indicators of water quality. We analyzed abiotic and biotic data, including habitat characteristics and presence of co-occurring trout and char (family Salmonidae) species, from 115 streams from the northern Idaho Panhandle to identify the physical characteristics and biotic communities of the streams associated with sculpin presence (or absence) and population density. For comparison, and to determine if the results of the northern dataset could be attributed to the rest of the state, a second dataset from state-wide sampling was also analyzed, as was a subset of both datasets that had no observations of non-native brook trout and rainbow trout. Sculpins were more likely to be present and in higher densities in streams with abundant riffle microhabitats that were mostly free of sediment (identified as Rosgen channel types B, C, and F for northern Idaho and types B and C for the entire state). More sculpins were also found in streams lacking brook trout and rainbow trout. Knowledge of sculpin habitats and the impacts of non-native salmonids may be useful in interpreting water quality evaluations, as well as in improving native fisheries restoration projects and fisheries management for Idaho streams.

Pheromone parsimony is widespread within the longhorned beetles (Coleoptera: Cerambycidae), which share a number of highly conserved volatile pheromone motifs. This parsimony reflects their life histories, ecology, and distribution. We conducted field bioassays testing attraction of cerambycids to 12 volatile pheromone lures at sites in both northern and southern Idaho over a period of three years. Our overall goals were to investigate the role of volatile pheromones in the geographic distribution of cerambycid species, interactions within cerambycid communities in reproductive isolation, and to identify attractive pheromones that can be used to develop lures for monitoring cerambycids. This study focused on the genus Tragosoma (subfamily: Prioninae). Trapping results suggested a regional split between populations of T. harrisii LeConte and T. soror Laplante within Idaho, with the more abundant of the two species at our sites being T. harrisii in northern Idaho and T. soror in southern Idaho. We found the flight periods of T. harrisii and T. soror overlapped, suggesting that flight period is not being used by these two species as a mechanism to prevent inter-specific cross-attraction among their populations in Idaho. Our results increase understanding of the ecology of Tragosoma species, and the role of pheromones and flight period phenology in maintaining reproductive isolation, and will aid in development of lures for monitoring cerambycids.

The Olympic mudminnow (Novumbra hubbsi) is a small freshwater fish, endemic to western Washington State. Although the species is listed as a Washington sensitive species, the lack of routine monitoring has resulted in poor understanding of population dynamics over time needed to support management and conservation actions. Olympic mudminnow commonly live in wetlands and associated low-gradient channels with tannic water and soft substrates, making conventional electrofishing and seine sampling approaches challenging and potentially inaccurate. Alternatively, minnow traps can easily be set in a wide range of depths and habitat types and allow for more systematic, repeated sampling. The study purpose was to conduct monthly surveys over a 19-month period to help develop standardized sampling methods. Sampling using baited Gee minnow traps set overnight was conducted in a wetland complex that flows into Eld Inlet in south Puget Sound, Washington. Catch rates of Olympic mudminnow were highest in late summer to early autumn (August through November) when water depths were low and water temperatures were decreasing. Trap mortality was relatively low for both Olympic mudminnow and amphibians but increased during warm spring and summer months. Eighty percent of the Olympic mudminnow captured were between 44 and 56 mm total length, and there was no difference in size between males and females. Gravid females were observed from October to June. Overall, minnow trapping appeared to be an effective method for monitoring Olympic mudminnow populations year round; however, sampling in the autumn appears to be advantageous because catch rates were high, and mortality was low.

Crappie (Pomoxis spp.) populations are challenging to manage due to highly variable year-class strength; however, such variability has rarely been investigated in western North America, where crappie often occupy large, steep-sided reservoirs prone to severe drawdown. We investigated the influence that various factors had on crappie abundance, as indexed by long-term trawling for larval fish and long-term electrofishing for older fish. Our primary findings were that: 1) autumn age-0 crappie abundance was higher in years when larval abundance and reservoir flow were higher in the summer; 2) spring age-1 crappie abundance was higher in years when fish were larger and more abundant entering their first winter, when hydraulic residence time was reduced and the reservoir volume was higher during the winter, and when predatory-sized smallmouth bass (Micropterus dolomieu) were more abundant in the spring (though the latter relationship was likely not causative but rather a parallel response to mutually advantageous environmental conditions in the reservoir); and 3) age-0 crappie entering their first winter were larger in years with lower summer larval crappie abundance and warmer summer water temperature. We recommend autumn electrofishing to monitor crappie populations in large canyon reservoirs, where shorelines are often too steep to sample fish with trap nets, because it provides an index of age-0 crappie abundance and size at the onset of their first winter as well as data on older crappie year classes and sympatric species; it also requires less sampling effort than summer trawling.