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Successful spore dispersal is a crucial part of the fungi life cycle, and many species achieve this using sporocarps which extend above the forest floor. The shape of sporocarps is known to affect dispersal success, but the local abiotic factors driving their morphology is understudied. In this study we examined the plasticity of sporocarp morphology and its effects on spore dispersal in the Pacific golden chanterelle (Cantharellus formosus). C. formosus that developed in sheltered microhabitats (n = 79), were measured to have significantly taller (P = 0.01) stipes and larger caps (P < 0.01) for a given stipe width compared to those developing in open microhabitats (n = 97). We were unable to detect increased dispersal success of C. formosus in field (n = 10). Longer stipes and larger caps are associated with increased dispersal abilities, while increased stipe thickness is connected to better stability. We suggest that sheltered C. formosus may grow into the open headspace, thus facilitating more effective spore dispersal. C. formosus growing in the open forest floor do not exhibit impeded dispersal and are thus shorter and smaller. Taken together, it is unlikely that there is a trade-off between morphologies that improve long distance dispersal or sporocarp stability.
A clipped adipose fin served as an effective external mark indicating presence of a coded-wire tag (CWT) in salmon (Oncorhynchus spp.) from the 1960s until the mid 1990s when hatcheries in the Pacific Northwest began mass marking released fish with an adipose fin clip, but not necessarily a CWT. Since then, many CWT sampling programs of commercial fisheries have transitioned to electronic-field detection, while others are still visual-field only, examining snouts from all adipose-clipped salmon, even those without CWTs. Because some CWT salmon are released from hatcheries without any external marks, visual-field only programs also fail to sample these CWTs. In 2012, we used electronic tag detection at a processing plant in Kodiak, Alaska, to scan 1,201 Chinook salmon (O. tschawytscha) caught as bycatch in the US North Pacific groundfish fisheries in the Gulf of Alaska (GOA). Chinook salmon bycatch were also electronically scanned in partnerships with private industry: 3,713 salmon in the 2013–2016 US rockfish fishery in the central GOA, and 611 salmon in testing of salmon excluder devices in 2013 in the central GOA groundfish fisheries. Electronic-field detection increased CWT recovery rates by 20–24% over visual-field detection of adipose-clipped Chinook salmon, and an estimated 64–74% of adipose-clipped Chinook salmon sampled had no CWTs. Visual-field only CWT sampling programs may unnecessarily process large numbers of untagged, adipose-clipped salmon while also recovering fewer CWTs than comparable electronic sampling programs.
North American beavers (Castor canadensis) were targeted within North American headwater landscapes by European loggers and fur traders in the 19th century, reducing beaver populations to near extinction by 1900. The extirpation of beavers from river networks has had profound effects on riparian zones, including channel geomorphology, temperature regimes, sediment storage, channel-floodplain connectivity, carbon storage and nutrient dynamics. Consequently, reintroducing beavers has been provisionally implemented as a restoration approach within some watersheds. We characterized how reintroduced beavers influence the short-term dynamics of organic material accumulation within the sediments of 1st and 2nd order streams within the Methow River watershed of Washington State. In collaboration with the Methow Beaver Project, we identified four creeks where they had reintroduced beavers within the past five years, as well as a control non-beaver pond. At each site, we collected shallow sediment cores from upstream, downstream, and within beaver ponds, and then measured organic material via elemental analyses of sediment carbon (%C) and nitrogen (%N) content. We compared those samples to sediments accumulated in local pond areas not created by beaver activity. Our results show greater organic C and N content of sediments in beaver ponds than non-beaver ponds. C/N ratios indicate elevated accumulation of allochthonous organic material in beaver impoundment sediments that would otherwise not be integrated into headwater streams from the terrestrial landscape. These findings suggest that the reintroduction of beavers could be an effective means to promote restoration of whole ecosystem function.
Pacific martens (Martes caurina) remain common in montane regions of the Pacific states, yet their distribution and status on the Olympic Peninsula, Washington, is uncertain. Between 1968–2008, six reliable marten detections exist; a dead juvenile female (2008) indicates martens were reproducing on the Peninsula within the last decade. To assess the status of martens, we describe carnivore surveys conducted from 1991–2008 (n = 223 stations). Additionally, we present results from three survey efforts we conducted from 2013–2016 (n = 747 stations). Although a suite of carnivore species was detected, surveys from 1991–2008 failed to detect either martens or fishers. Surveys from 2013–2016 detected reintroduced fishers, and resulted in two marten detections near Mt. Olympus, 4 km apart. A marten was photographed opportunistically near Mt. Cruiser in 2015, 44 km from Mt. Olympus. Altogether, nine reliable detections of Pacific martens were obtained between 1968 and 2016, including three since 2008. Evidence suggests martens are absent from the lower elevation regions they once occupied and occur at exceedingly low densities at higher elevations. To understand the trend in marten populations on the Peninsula and develop appropriate conservation strategies, additional broad- and fine-scale surveys using detection devices that enable the genetic identification of individuals will be needed.
Salt marsh habitats support a diverse array of estuarine species but are vulnerable to increased inundation resulting from sea-level rise. In order to characterize relationships between vegetation and elevation and inform assessments of risk to salt marsh communities from projected sea-level rise, we collected vegetation and elevation data at 42 salt marsh sites in Coos Bay Estuary, Oregon. For 1-m2 plots along transects from the bayside edge to the upland, we recorded height and percent cover of all plant species present. We determined plot location and elevation at 1-m intervals with a Trimble Pathfinder Pro XRS differential GPS and TOPCON GTS223 Total Station for comparison with existing LiDAR. Cluster analysis distinguished six vegetation groups. Two low marsh groups (average elevation 1.74 and 1.91 m) were characterized by swampfire (Sarcocornia perennis) with an average height of 31 cm, and saltgrass (Distichlis spicata) with an average height of 22 cm. Plots in the high marsh groups had average elevations ranging from 2.21 to 2.57 m and were characterized by tufted hairgrass (Deschampsia cespitosa) and Oregon gumweed (Grindelia stricta var. stricta), with an average height of 50 cm and 43 cm, respectively. Mid-marsh groups (average elevations of 2.01 and 1.99 m) were dominated by Lyngbye's sedge (Carex lyngbyei) with an average height of 64 cm. The data collected along these transects allowed us to assess LiDAR elevation accuracy, identify sites where LiDAR data require correction, and provide species-specific height data for correction of LiDAR in areas of dense vegetation.
Field studies of arthropod abundance may also need to know biomass. Biomass is used in studies of food web structure and tropic cascades, and for estimating vertebrate food sources and plant damage from herbivory. Weighing individual insects is time-consuming and body length is a more practical field measurement. We develop an allometric equation for arthropod biomass (wet and dry weight) as a function of length for application to field studies in the Pacific Coast region, USA. Our results are consistent with prior all-taxa equations.