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At least 955 records · Page 53Linked to original sources

USGS2015

Forecasting sagebrush ecosystem components and greater sage-grouse habitat for 2050: learning from past climate patterns and Landsat imagery to predict the future

Sagebrush ( Artemisia spp.) ecosystems constitute the largest single North American shrub ecosystem and provide vital ecological, hydrological, biological, agricultural, and recreational ecosystem services. Disturbances have altered and reduced this ecosystem historically, but climate change may ultimately represent the greatest future risk. Improved ways to quantify, monitor, and predict climate-driven gradual change in this ecosystem is vital to its future management. We examined the annual change of Daymet precipitation (daily gridded climate data) and five remote sensing ecosystem sagebrush vegetation and soil components (bare ground, herbaceous, litter, sagebrush, and shrub) from 1984 to 2011 in southwestern Wyoming. Bare ground displayed an increasing trend in abundance over time, and herbaceous, litter, shrub, and sagebrush showed a decreasing trend. Total precipitation amounts show a downward trend during the same period. We established statistically significant correlations between each sagebrush component and historical precipitation records using a simple least squares linear regression. Using the historical relationship between sagebrush component abundance and precipitation in a linear model, we forecasted the abundance of the sagebrush components in 2050 using Intergovernmental Panel on Climate Change (IPCC) precipitation scenarios A1B and A2. Bare ground was the only component that increased under both future scenarios, with a net increase of 48.98 km 2 (1.1%) across the study area under the A1B scenario and 41.15 km 2 (0.9%) under the A2 scenario. The remaining components decreased under both future scenarios: litter had the highest net reductions with 49.82 km 2 (4.1%) under A1B and 50.8 km 2 (4.2%) under A2, and herbaceous had the smallest net reductions with 39.95 km 2 (3.8%) under A1B and 40.59 km 2 (3.3%) under A2. We applied the 2050 forecast sagebrush component values to contemporary (circa 2006) greater sage-grouse ( Centrocercus urophasianus ) habitat models to evaluate the effects of potential climate-induced habitat change. Under the 2050 IPCC A1B scenario, 11.6% of currently identified nesting habitat was lost, and 0.002% of new potential habitat was gained, with 4% of summer habitat lost and 0.039% gained. Our results demonstrate the successful ability of remote sensing based sagebrush components, when coupled with precipitation, to forecast future component response using IPCC precipitation scenarios. Our approach also enables future quantification of greater sage-grouse habitat under different precipitation scenarios, and provides additional capability to identify regional precipitation influence on sagebrush component response.

Wyoming↗

USGS2016

California State Waters map series — Offshore of Aptos, California

Introduction In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar bathymetric data (the undersea equivalent of satellite remote-sensing data in terrestrial mapping), acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow subsurface geology. The Offshore of Aptos map area is located on the Pacific Coast, on the north side of Monterey Bay, about 105 km southeast of San Francisco. The largest incorporated city in the map area, Capitola, and numerous unincorporated towns including Aptos, lie on uplifted marine terraces between the shoreline, and the northwest-trending Santa Cruz Mountains, part of California’s Coast Ranges. The map area includes the northernmost part of Santa Cruz Harbor, and Moss Landing Harbor is located about 10 km south of the map area. The offshore part of the map area is entirely within California’s State Waters and is also part of the Monterey Bay National Marine Sanctuary. In the southern part of the map area, the Soquel Canyon State Marine Conservation Area extends eastward from the limit of California’s State Waters across Soquel Canyon. The Offshore of Aptos map area is on the western margin of North American Plate—the only continental margin in the world delineated largely by transform faults. The San Andreas Fault Zone cuts through the Santa Cruz Mountains just 3.5 km northeast of the map area. The San Gregorio Fault Zone, another major plate-boundary structure, cuts through Monterey Canyon about 13 km southwest of the map area. Ongoing deformation associated with and between these major fault zones has uplifted the Santa Cruz Mountains and formed well-developed sets of marine terraces that characterize almost the entire coastal zone of the map area. The offshore part of the map area consists of relatively flat and shallow continental shelf which is underlain by variable amounts (0 to 30 m) of upper Quaternary shelf, estuarine, and fluvial sediments deposited as sea level fluctuated in the late Pleistocene. Along the southern edge of the map area, the shelf is incised by the head of Soquel Canyon, a northeast-trending tributary to the west-trending Monterey Canyon. During the last sea-level lowstand (the Last Glacial Maximum [LGM], about 21,000 years ago) Soquel Creek flowed through a paleochannel across the emergent shelf into the head of Soquel Canyon. This canyon was disconnected from its onshore watershed during the post-LGM sea-level rise of about 125 m; the abandoned paleochannel was subsequently filled with marine sediment. Coastal sediment in the Offshore of Aptos map area is supplied by coastal watersheds and bluff erosion. Sediment transport in this part of the Santa Cruz littoral cell is primarily from the northwest to the southeast and terminates in the submarine Monterey Canyon. Longshore drift is impeded by jetties at Santa Cruz Harbor, resulting in high beach erosion rates east of the harbor. Sediment dredged from the harbor mouth (estimated 300,000 yds 3 /yr) is currently being used to nourish beaches directly to the east. Farther downcoast, the rapidly eroding beach at Capitola was stabilized by construction of an about 75-m-long groin. This part of central California is exposed to large North Pacific swells from the northwest throughout the year. North Pacific swell heights range from 2 to 10 meters, with larger swells occurring from October to May. During El Niño-Southern Oscillation (ENSO) events, winter storms track farther south than they do in normal (non-ENSO) years, thereby impacting the map area more frequently and with waves of larger heights. Bedrock exposed in coastal cliffs is relatively erosion-resistant, and significant erosional events primarily are restricted to storm-wave activity that also erodes the overlying unconsolidated marine-terrace sediments. The Offshore of Aptos map area lies within the cold-temperate biogeographic zone that is called either the “Oregonian” province or the “northern California ecoregion.” This biogeographic province is maintained by the long-term stability of the southward-flowing California Current, the eastern limb of the North Pacific subtropical gyre that flows from southern British Columbia to Baja California. At its midpoint off central California, the California Current transports subarctic surface (0–500 m deep) waters southward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. The south end of the Oregonian province is at Point Conception (about 310 km southeast of the map area), although its associated phylogeographic group of marine fauna may extend beyond to the area offshore of Los Angeles in southern California. The ocean off of central California has experienced a warming over the last 50 years that is driving an ecosystem shift away from the productive subarctic regime towards a depopulated subtropical environment. Seafloor habitats in the Offshore of Aptos map area lie within the “Shelf” Megahabitat class and include patchy rocky habitats, gravel-rich scour depressions, minor bedrock habitat, and predominantly sandy inner shelf. Sandy shelf habitats grade offshore to mud-dominated habitats on the midshelf in deeper water. Biological productivity resulting from coastal upwelling supports populations of Sooty Shearwater, Western Gull, Common Murre, Cassin’s Auklet, and many other less populous bird species. In addition, an observable recovery of Humpback and Blue Whales has occurred in the area; both species are dependent on coastal upwelling to provide nutrients. California sea lions and Pacific harbor seals are abundant in the map area. Common bottlenose dolphins are often observed very close to shore and in the surf zone. The large extent of exposed inner shelf bedrock supports large forests of “bull kelp,” which is well adapted for high-wave-energy environments. The kelp beds are the northernmost known habitat for the population of southern sea otters. Common fish species found in the kelp beds and rocky reefs include blue rockfish, black rockfish, olive rockfish, kelp rockfish, gopher rockfish, black-and-yellow rockfish, painted greenling, kelp greenling, and lingcod.

California↗

USGS2007

The role of headwater streams in downstream water quality

Knowledge of headwater influences on the water-quality and flow conditions of downstream waters is essential to water-resource management at all governmental levels; this includes recent court decisions on the jurisdiction of the Federal Clean Water Act (CWA) over upland areas that contribute to larger downstream water bodies. We review current watershed research and use a water-quality model to investigate headwater influences on downstream receiving waters. Our evaluations demonstrate the intrinsic connections of headwaters to landscape processes and downstream waters through their influence on the supply, transport, and fate of water and solutes in watersheds. Hydrological processes in headwater catchments control the recharge of subsurface water stores, flow paths, and residence times of water throughout landscapes. The dynamic coupling of hydrological and biogeochemical processes in upland streams further controls the chemical form, timing, and longitudinal distances of solute transport to downstream waters. We apply the spatially explicit, mass-balance watershed model SPARROW to consider transport and transformations of water and nutrients throughout stream networks in the northeastern United States. We simulate fluxes of nitrogen, a primary nutrient that is a water-quality concern for acidification of streams and lakes and eutrophication of coastal waters, and refine the model structure to include literature observations of nitrogen removal in streams and lakes. We quantify nitrogen transport from headwaters to downstream navigable waters, where headwaters are defined within the model as first-order, perennial streams that include flow and nitrogen contributions from smaller, intermittent and ephemeral streams. We find that first-order headwaters contribute approximately 70% of the mean-annual water volume and 65% of the nitrogen flux in second-order streams. Their contributions to mean water volume and nitrogen flux decline only marginally to about 55% and 40% in fourth- and higher-order rivers that include navigable waters and their tributaries. These results underscore the profound influence that headwater areas have on shaping downstream water quantity and water quality. The results have relevance to water-resource management and regulatory decisions and potentially broaden understanding of the spatial extent of Federal CWA jurisdiction in U.S. waters. ?? 2007 American Water Resources Association.

Journal of the American Water Resources Associatio↗

USGS2006

Ontogenesis of endangered humpback chub (Gila cypha) in the Little Colorado River, Arizona

The largest population of endangered humpback chub Gila cypha inhabits the Colorado River below Glen Canyon Dam and the lower 14 km of the Little Colorado River (LCR), Arizona. Currently, adults from both rivers spawn and their progenies grow and recruit to adulthood primarily within the LCR, where we studied G. cypha 's life history using hoop net capture data. Humpback chub undergo an ontogenesis from diurnally active, vulnerable, nearshore-reliant young-of-the-year (YOY; 30–90 mm total length) into nocturnally active, large-bodied adults (≥180 mm TL). During the day, adults primarily resided in deep midchannel pools; however, at night they dispersed inshore amongst the higher densities of YOY conspecifics. Many YOY G. cypha shifted to nocturnal habitats that provided greater cover, possibly, to avoid inshore invading adults. These findings mirror predator-prey scenarios described in other freshwater assemblages, but do not refute other plausible hypotheses. Gila cypha piscivorous activity may escalate in hoop nets, which can confine fish of disparate sizes together; adults were significantly associated with YOY conspecifics and small dead fish in hoop nets at night and eight G. cypha (156–372 mm TL) regurgitated and/or defecated other fish body parts during handling following capture. Gila cypha can definitely be piscivorous given the opportunity, but the magnitude of their piscivorous activity in the wild is debatable.

Arizona↗

USGS2021

White-nose Syndrome and environmental correlates to landscape-scale bat presence

Over the past 13 years, White-nose Syndrome (WNS) has caused North American bat population declines and shifted community structure towards species less or unaffected by the disease. Mist-netting, acoustic surveys, and cave count data have been used to document changes in bat presence and activity through site-specific, pre- and post-WNS studies. Management and survey guidance often must be applied at a combined landscape and site-specific scale. Our objective was to explore the relationships among WNS impact, influence of available hibernacula, and environmental factors for the nightly presence of 3 WNS-affected bats: the Indiana bat ( Myotis sodalis ), northern long-eared bat ( M. septentrionalis ), and big brown bat ( Eptesicus fuscus ). We used recordings from 10 acoustic monitoring study areas, each with 3 survey locations across the states of Virginia, West Virginia, Ohio and Kentucky to assess changes in nightly bat presence during the summer of 2017. There were significant positive and negative correlates of broad land-cover categories for presence of all 3 bat species. Our findings also corroborated trends in abundance and distribution patterns found in prior, smaller-scale studies, supporting the relevance of land cover categories in a large-scale acoustic monitoring framework. We observed a negative association between WNS impact-years and nightly northern long-eared bat presence, but low occurrence and patchy distribution reduced our ability to infer strong relationships. Big brown bat presence showed a significant positive relationship with WNS occurrence on the landscape, providing evidence that big brown bats are maintaining populations after years of exposure. Indiana bats were the least-documented species, limiting the strength of our conclusions, but we did observe significant temporal patterns in nightly presence, with higher probabilities of presence earlier in the summer. Our results show the potential efficacy of using a WNS impact metric to predict summer bat presence, inform current U.S. Fish and Wildlife Service acoustic monitoring guidelines, and highlight which environmental variables are relevant for large-scale acoustic monitoring.

Wildlife Society Bulletin↗

USGS2010

Remagnetization and northward coastwise transport of Franciscan Complex rocks, northern California: A reinterpretation of the paleomagnetic data

Previous paleomagnetic studies of accreted oceanic rocks within the Franciscan Complex of northern California have concluded that these rocks originated far to the south of their present positions with respect to the North American continent. Based on positive “fold” tests, the characteristic remanent magnetizations were inferred to predate accretion-related deformation and metamorphism, and to have been acquired during or soon after deposition of these rocks. Thus, the paleomagnetic data were thought to provide direct information on ancient oceanic plate motions. However, the plate motions implied by some of these paleomagnetic data are problematic (e.g., exceptional plate velocities), and uniform-polarity magnetizations in almost all of these rocks indicate the possibility of remagnetization. Recent work on oceanic rocks in similar subduction complexes of Japan and Mexico have shown that they were most likely chemically remagnetized during accretion prior to disruption of the original stratigraphic sequences. Modern analogs indicate that the oceanic rocks in Mexico were probably remagnetized while still part of a shallow-dipping subducting slab (<10°) at the base of an accretionary prism. Assuming these rocks were near horizontal at the time of remagnetization, paleolatitudes at which these rocks were subducted and subsequent arc-parallel displacements along the western margin of North America can be inferred. In this paper, Franciscan rocks in northern California are reinterpreted as also having been remagnetized prior to accretion-related deformation. This scenario satisfies both geologic and paleomagnetic constraints for these rocks, and resolves conflicts between data indicating both remagnetization and tectonic displacement. Transport of the Laytonville Limestone from the southern hemisphere is not required. Paleolatitudes of subduction and remagnetization in the northern hemisphere (12° to 33°) appear to be inversely proportional to age of accretion (middle Cretaceous to Oligocene) for the Franciscan rocks. Subsequent northward diplacements (800 to 3700 km) and clockwise rotations (56° and 154°) of these rocks inferred from the paleomagnetic data are consistent with potential displacements along the western margin of North America during late Mesozoic and Cenozoic time calculated using examples of modern subduction zones and current plate reconstruction models.

California↗

USGS2002

Electrofishing for crappies: Electrical settings influence immobilization efficiency, injury, and mortality

Continuous direct current (DC) and pulsed DC (PDC) of varying frequency and pulse period are commonly used to immobilize and collect crappies Pomoxis spp. in freshwater. However, little information is available about the minimum electrical-setting thresholds required for immobilization or how the settings relate to incidence of injury. We investigated the effect of increasing power densities on the immobilization and injury of black crappies P. nigromaculatus (average total length = 154 mm) treated with DC and various PDC settings. Forced swimming toward the electrodes was observed in black crappies exposed to DC, but that was less apparent for PDC. The minimum peak power densities required to immobilize black crappies ranged from 0.10 to 6.5 mW/cm3 and depended on pulse frequency and period. The incidence of hemorrhaging ranged from 0% to 50% and that of spinal damage from 9% to 45%. However, the severity of injury also depended on pulse frequency and period. No fish suffered mortality at or below the immobilization thresholds, but mortality ranged from 0% to 15% at settings above the thresholds. Mortality was observed with PDC settings of 15 Hz only. Fish that were tetanized following electrical treatment were more prone to injury than those that exhibited narcosis.

North American Journal of Fisheries Management↗

USGS2024

Seasonal movements between mainstem and tributaries may facilitate the persistence of Roundtail Chub and Flannelmouth Sucker within an altered stream system

Objective Movement enables animals to complete their life history by responding to changing environmental conditions. Linking movement behaviors to life history characteristics can allow more targeted management applications for declining native fish populations. We identified seasonal movement patterns of Roundtail Chub Gila robusta and Flannelmouth Sucker Catostomus latipinnis , two understudied species that currently occupy only a portion of their historical range within the Colorado River Basin. Methods We coupled Passive Integrated Transponder tag antenna systems with multi-state capture-recapture models to quantify juvenile and adult movement between mainstem and tributary habitat within the Blacks Fork subbasin of southwest Wyoming, U.S.A. during 2019–2021. We also evaluated how flow and temperature may cue the timing of seasonal movements. Result Adults from both species made spring spawning movements to reach upstream tributary habitat, though adult Flannelmouth Sucker movements were more common and longer. Roundtail Chub primarily moved into the Hams Fork while Flannelmouth Sucker primarily moved into Muddy Creek, an intermittent tributary that was also identified as important for juvenile rearing. Juvenile movements occurred primarily during the fall months, with distance traveled comparable between species. Temperature and flow influenced the timing of spring spawning movements in adult Flannelmouth Sucker, with low flow potentially limiting access to preferred spawning habitat. Conclusion Identified movements likely contribute to Roundtail Chub and Flannelmouth Sucker persistence within this highly altered stream system and ultimately provide insights for management and recovery strategies to prevent further population declines.

Wyoming↗

USGS2023

Evaluation of fall-seeded cover crops for grassland nesting waterfowl in eastern South Dakota

The Prairie Pothole Region (PPR) is the primary breeding ground for many species of North American waterfowl. The PPR was historically dominated by mixed and tallgrass prairies interspersed with wetlands, but >70% of the native grassland area has been lost due to widespread conversion to croplands. Cover cropping is a reemerging farming technique that may provide suitable nesting cover for grassland nesting waterfowl in active croplands, but waterfowl nest survival in fall cover-cropped fields has not been evaluated. We studied use (nest abundance and density) and nest survival of breeding waterfowl in fall-seeded cover crops and perennial cover during 2018 and 2019. We searched 2,094 ha of cover crops and 1,604 ha of perennial cover and found 123 and 304 duck nests, respectively, in each cover type. Estimated nest success (34-day interval) was 3.7% and 16.6% in cover crops during 2018 and 2019, respectively, versus 22.1% in 2018 and 24.9% in 2019 in perennial cover, with increased success of cover-crop fields in 2019 resulting from precipitation that prevented most fields from being planted to row crops. In a model that included effects of planting, daily nest survival in perennial cover was 0.944 (SD = 0.026) in 2018 and 0.960 (SD = 0.019) in 2019. Estimated daily nest survival was 0.912 (SD = 0.040) in 2018 and 0.960 (SD = 0.019) in 2019 during intervals when planting did not occur, but was only 0.417 (SD = 0.124) in 2018 and 0.612 (SD = 0.117) in 2019 on the day that planting occurred. Estimated nest densities in 2018 and 2019, adjusted for nests that failed prior to discovery, were 5.1 (SE = 1.1) and 11.0 (SE = 3.1) nests 100-ha −1 in perennial cover, but only 2.1 (SE = 0.8) and 2.6 (SE = 0.7) in cover crops, respectively. Based on observed nest initiation and planting dates, about 70% of duck nests in cover crops would experience planting events in a typical growing season. Our results suggest that under current management techniques, fall-seeded cover crops offer poor nesting habitat for waterfowl; however, the important benefits cover crops provide to soil health, water quality, and other ecosystem services remain.

South Dakota↗

USGS2026

Establishing realistic length standards for Cutthroat Trout, Rainbow Trout, and Mountain Whitefish

Objective Proportional size distribution (PSD) is a simple index used to summarize length data that is easily communicated, provides insight on fish population dynamics (e.g., growth, recruitment), and is often used to establish management objectives. However, the current length categories for Cutthroat Trout Oncorhynchus clarkii and Rainbow Trout O. mykiss were based on the all-tackle world records (an atypically large adfluvial Cutthroat Trout and a steelhead [anadromous Rainbow Trout]). Consequently, the length categories (stock [S], quality [Q], preferred [P], memorable [M], trophy [T]) are so large for these two species that the index is of limited use for most populations throughout western North America, particularly for large length-groups. In addition, length standards have not been proposed for Mountain Whitefish Prosopium williamsoni . As such, we sought to provide new length standards for Cutthroat Trout, Rainbow Trout, and Mountain Whitefish that allow fisheries scientists to calculate useful PSD values. Methods We compiled data from nearly 3 million fish across the western United States. A percentile-based approach was used to identify the individual total length that would form the basis of estimating length standards. We placed each fish into its respective 10-digit hydrological unit code, obtained the maximum length (all lengths are total length) for each 10-digit hydrological unit code by species, and then identified the 99th percentile of the maximum lengths. The species-specific 99th percentile value was then used to estimate potential length standards for each length category. For Mountain Whitefish, we used the current world-record length as the basis for generating length standards. We compared PSDs calculated using existing and revised length standards to provide insight on potential issues with the proposed values. Results We propose the following minimum total lengths for PSD calculations: 18 cm (7 inches; S), 28 cm (11 inches; Q), 35 cm (14 inches; P), 43 cm (17 inches; M), and 53 cm (21 inches; T) for Cutthroat Trout; 20 cm (8 inches; S), 30 cm (12 inches; Q), 40 cm (16 inches; P), 50 cm (20 inches; M), and 60 cm (24 inches; T) for Rainbow Trout; and 15 cm (6 inches; S), 25 cm (10 inches; Q), 30 cm (12 inches; P), 38 cm (15 inches; M), and 48 cm (19 inches; T) for Mountain Whitefish. Revised values provided more realistic estimates of PSD for Cutthroat Trout and Rainbow Trout than existing values. The proposed length standards for Mountain Whitefish resulted in PSD values that were realistic and useful for characterizing length structure. Conclusions The length standards presented here provide fisheries scientists with tools to aid in the study and management of Cutthroat Trout, Rainbow Trout, and Mountain Whitefish populations.

Colorado, Idaho, Montana, Nevada, Oregon, Utah, Wa↗

USGS1998

The North American Bird Banding Program: Into the 21st century

The authors examined the legal, scientific, and philosophical underpinnings of the North American Bird Banding Program [BBP], with emphasis on the U.S. Bird Banding Laboratory [BBL], but also considering the Canadian Bird Banding Office [BBO]. In this report, we review the value of banding data, enumerate and expand on tile principles under which any modern BBP should operate, and from them derive our recommendations. These are cast into a Mission Statement, a Role and Function Statement, and a series of specific recommendations addressing five areas: (1) permitting procedures and practices; (2) operational issues; (3) data management; (4) BBL organization and staffing; and (5) implementation. Our major tenets and recommendations are as follows: banding provides valuable data for numerous scientific, management, and educational purposes, and its benefits far outweigh necessary biological and fiscal costs, especially those incurred by the BBL and BBO; because of the value of banding data for management of avian resources, including both game and nongame birds, government support of the program is fully justified and appropriate; all banding data, if collected to appropriate standards, are potentially valuable; there are many ways to increase the value of banding data such as by endorsing, promoting, and applying competence and/or training standards for permit issuance; promoting bander participation in well-designed projects; and by encouraging the use of banding data for meta-analytical approaches; the BBL should apply, promote, and encourage such standards, participation, and approaches; the BBP should be driven by the needs of users, including scientists and managers; all exchange of data and most communication between banders and the BBL should become electronic in the near future; the computer system at the BBL should be modernized to one designed for a true client-server relationship and storage of data in on-line relational databases; the BBL should continue to maintain high quality control and editing standards and should strive to bring all data in the database up to current standards; however, the BBL should transfer a major portion of the responsibility for editing banding data to the bander by providing software that will permit the bander to edit his/her own data electronically before submission to the BBL; the BBL should build the capacity to store additional data tied to original band records able to be pre-edited and submitted electronically, such as recapture data, appropriate data from auxiliary marking (e.g. resightings of color-marked birds), and other data that gain value when pooled from many banders (e.g., measurements); however, the BBL should only accept such data if they are collected using standardized methods and as part of an established program designed to utilize such data; now is the time to consider options for implementing a Western Hemisphere banding program, with leadership from the BBL; the Patuxent Electronic Data Processing Section should become part of the BBL; additional scientific and technical staff must be added to the BBL; an Implementation Team should be formed to expedite our recommendations, following timetables outlined in this document.

Journal of Field Ornithology↗

USGS1981

Birds of the St. Croix River valley: Minnesota and Wisconsin

The St. Croix River Valley encompasses nearly 11,550 km2 in east-central Minnesota and northwestern Wisconsin. A wide range of habitats are available for birds including upland oak, lowland deciduous, maple-basswood, lowland and upland coniferous forests, natural basin wetlands, and grasslands. Situated in the north-central region of the United States, the valley is a biological 'crossroads' for many species. Because of the mixed affinities of plant communities, the valley includes the northern and southern range limits for a number of species. Also, because the valley lies near the forest-prairie transition zone, many typical western breeding species (e.g. pintail, western meadowlark, yellow-headed blackbird) breed in proximity to typical eastern species such as tufted titmouse, eastern meadowlark, and cardinal. From 1966 to 1980, I conducted extensive surveys of avian distribution and abundance in the St. Croix River Valley. I have supplemented the results of these surveys with published and unpublished observations contributed by many ornithologists. These additional data include compilations from Christmas Bird Counts sponsored by the National Audubon Society and from the Breeding Bird Survey coordinated by the U.S. Fish and Wildlife Service. Three hundred fourteen species have been recorded in the study area; data are presented on the migration period, nesting season distribution, winter distribution, relative abundance, and habitat use of each species. Recognizing the uniqueness of the area, and its importance not only to wildlife but also to man, the U.S. Congress designated the St. Croix a National Scenic Riverway. This action provided a considerable degree of protection to lands along and directly adjacent to the river. Unfortunately, no similar legal measure exists to protect lands away from the river. With the exception of the northern quarter of the St. Croix River Valley, agricultural interests have made significant inroads into the habitat base. The continuing expansion of the nearby Minneapolis-St. Paul metropolitan region has degraded or destroyed many woodlots, upland fields, and wetlands. In numerous instances, degradation of natural habitats has influenced the abundance and distribution of bird species. Because of these changes, both the Federal government and State Departments of Natural Resources have listed several species in various categories based on their current status. In the St. Croix River Valley, seven species are endangered, eight are threatened, and 29 are watch or priority status in either or both states. Data presented in this report are of value to land managers, land use specialists, and ornithologists, in assessing current and projected habitat alterations on the avifauna of this valley. The St. Croix River bisects a large region of western Wisconsin and east central Minnesota that exhibits a wide range of habitat types. This region supports not only birds, but many mammals, fishes, reptiles and amphibians, and several thousand species of vascular and nonvascular plants. The river itself is relatively clean through most of its course, and its natural flow is interrupted by only two small dams. Because the river lies within a 1-day drive of nearly 10 million people (Waters 1977), use of the area for recreational purposes is extremely heavy. Recreational pursuits include sunbathing, boating, and wild river kayaking in the summer, and ice fishing and cross-country skiing in the winter. The large number of unique and highly fragile habitats that exist there may never be compatible with the uses and abuses of the land that go with expanding human populations. Through the efforts of a number of citizens concerned with the quality of their environment and the foresightedness of several local, State, and Federal legislators, a portion of the upper St. Croix River Valley (hereafter termed 'the Valley') was established as a National Wild and Scenic River. Through establishment of t

North American Fauna↗

USGS2006

San Francisco 's Golden Gate: A bridge between historically distinct coyote (Canis latrans) populations?

Although coyotes ( Canis latrans ) are well-known for their adaptability to human-modified landscapes (Riley et al. 2003), as with any medium to large-sized carnivore, they typically avoid highly urbanized areas (Crooks 2002), preferring instead to use habitat fragments linked by vegetated corridors (Tigas et al. 2002). However, recent observations of coyotes in San Francisco indicate their willingness to traverse even the most densely urbanized terrain (Rubenstein 2003). Herein we use DNA to show, in an extreme example, that an adult male coyote caught in the northern tip of the San Francisco peninsula traversed the 2-km Golden Gate Bridge, potentially linking historically distinct coyote populations. We extracted DNA from the blood of a coyote that was captured, radio-collared, and released in May 2003 in the Presidio of San Francisco, part of the Golden Gate National Recreation Area located south of the Golden Gate Bridge. This coyote apparently left the park within a week and was not subsequently located. We genotyped this individual at 14 autosomal (non-sex-linked) microsatellite loci that had previously been used to delimit 4 coyote populations in central California (Sacks et al. 2004). Laboratory methods are detailed in a previous publication (Sacks et al. 2004). By comparing this genotype to the 2 adjacent populations, the North Coastal Mountain population (beginning 20 km north of the bridge) and the South Bay Hills population (20 km south of the Bridge, just south of the city), we assigned his origin to the northern population with 97.5% probability using a Bayesian model-based approach (Pritchard et al. 2000). The population of origin was the same when all 4 central California populations were used. Next, we genotyped this male and males in the 2 adjacent populations at 2 Y-chromosome loci (MS41A, MS41B; Sundqvist et al. 2001). The genotype of this male was present in 43 of 63 males from the northern population and none of 18 males (conservatively assumed to be 1 of 18 for probability calculation) in the southern population, indicating a 92% probability of origin in the northern population based on the Y-genotype. The combined probability of assignment (Sokal and Rohlf 1995) to the northern population based on both types of marker was 99.5%, making it almost certain that this coyote came from north of the Bridge. Although it is conceivable that the coyote was transported by humans or arrived in the Presidio without having traversed the Bridge, these scenarios seem unlikely. First, the coyote had no apparent injuries and, based on tooth wear, was several years old, making it unlikely that he had been in the recent custody of a wildlife rehabilitator (a general inquiry to all known wildlife rehabilitators in the area also turned up no information). Second, he was observed in the San Francisco park at the south end of the Bridge, a likely destination for a coyote that had walked across the Bridge, but not a likely choice as a new release site for a coyote. Third, while canids are generally good swimmers, it seems implausible that a coyote could swim across the San Francisco Bay, which has extremely treacherous currents. Finally, assuming his journey was unassisted, any land route other than the Golden Gate Bridge would have required him to circumvent the San Francisco Bay–Delta Estuary and move through the South Bay Hills population (>250 km). Because no coyotes captured in the South Bay Hills population had genetic profiles indicative of a northern origin (Sacks et al. 2004), this seems especially unlikely. Coyotes were most likely absent from the peninsula north of the Bridge when the Bridge was built in 1933 and have only recently begun recolonizing the area (Hall 2000). The recent southern recolonization of this area by coyotes, their apparent willingness to cross the Bridge, and recent documentation of coyotes in more central parts of San Francisco (Rubenstein 2003) indicate the possibility of direct gene flow between north-coastal and south-coastal coyote populations, which have been historically distinct (Sacks et al. 2004). Although it has been widely recognized that human fragmentation of the landscape can impede gene flow among parts of historically continuous populations, our findings reflect an example where a human modification to the landscape may have done the opposite—namely, facilitated gene flow between historically distinct sections of a species range.

California↗

USGS2015

Translocation of Humpback Chub into tributary streams of the Colorado River: Implications for conservation of large-river fishes

The Humpback Chub Gila cypha , a large-bodied, endangered cyprinid endemic to the Colorado River basin, is in decline throughout most of its range due largely to anthropogenic factors. Translocation of Humpback Chub into tributaries of the Colorado River is one conservation activity that may contribute to the expansion of the species’ current range and eventually provide population redundancy. We evaluated growth, survival, and dispersal following translocation of approximately 900 Humpback Chub over a period of 3 years (2009, 2010, and 2011) into Shinumo Creek, a tributary stream of the Colorado River within Grand Canyon National Park. Growth and condition of Humpback Chub in Shinumo Creek were consistent among year-classes and equaled or surpassed growth estimates from both the main-stem Colorado River and the Little Colorado River, where the largest (and most stable) Humpback Chub aggregation remains. Based on passive integrated tag recoveries, 53% ( = 483/902) of translocated Humpback Chub dispersed from Shinumo Creek into the main-stem Colorado River as of January 2013, 35% leaving within 25 d following translocation. Annual apparent survival estimates within Shinumo Creek ranged from 0.22 to 0.41, but were strongly influenced by emigration. Results indicate that Shinumo Creek provides favorable conditions for growth and survival of translocated Humpback Chub and could support a new population if reproduction and recruitment occur in the future. Adaptation of translocation strategies of Humpback Chub into tributary streams ultimately may refine the role translocation plays in recovery of the species.

Arizona↗

USGS2025

Electric field-induced detachment and vibration analysis for Sea Lamprey

Objective: Sea lamprey Petromyzon marinus , a known ecological threat to native fish populations in the Great Lakes, use their oral suction disc to navigate challenging environments when moving upstream to spawn. This study investigated the physiological response of adult sea lamprey to detach under pulsed direct current electric fields. Methods: Adult sea lampreys in an attaching position were exposed to pulsed direct current electric fields at four different field strengths (0.7, 1.1, 1.3, and 1.9 V/cm). Behavioral responses, including detachment and vibration, were observed and analyzed. Fast Fourier Transform analysis was applied to vibration data to quantify the frequency of vibration exhibited by non-detached sea lamprey. Statistical correlations between detachment rates and vibration responses to sea lamprey sex, weight, and length were evaluated to determine influencing factors. Results: The highest detachment rate (91%) was observed at 1.1 V/cm, with the detachment rate above 70% for other field strengths. Fast Fourier Transform analysis revealed that the vibration frequencies closely matched the signal while stronger fields elicited a more pronounced vibration amplitude without significantly increasing detachment. Non-detached sea lampreys exhibited “twitching” behavior synchronized with the electric field frequency. Sex, weight, and length had minimal influence on detachment rates and vibration responses. Conclusion: This study provided insights into the behavioral responses of sea lamprey under electric fields, highlighting the potential for optimizing electric deterrents for selective control. While not all sea lampreys detach during electroshocking, understanding their behavior can be crucial in maximizing detachment rates and contributing to improved management strategies for this invasive species.

Transactions of the American Fisheries Society↗

USGS2006

Variables influencing the presence of subyearling fall Chinook salmon in shoreline habitats of the Hanford Reach, Columbia River

Little information currently exists on habitat use by subyearling fall Chinook salmon Oncorhynchus tshawytscha rearing in large, main-stem habitats. We collected habitat use information on subyearlings in the Hanford Reach of the Columbia River during May 1994 and April-May 1995 using point abundance electrofishing. We analyzed measures of physical habitat using logistic regression to predict fish presence and absence in shoreline habitats. The difference between water temperature at the point of sampling and in the main river channel was the most important variable for predicting the presence and absence of subyearlings. Mean water velocities of 45 cm/s or less and habitats with low lateral bank slopes were also associated with a greater likelihood of subyearling presence. Intermediate-sized gravel and cobble substrates were significant predictors of fish presence, but small (<32-mm) and boulder-sized (>256-mm) substrates were not. Our rearing model was accurate at predicting fish presence and absence using jackknifing (80% correct) and classification of observations from an independent data set (76% correct). The habitat requirements of fall Chinook salmon in the Hanford Reach are similar to those reported for juvenile Chinook salmon in smaller systems but are met in functionally different ways in a large river.

Washington↗

USGS2017

Factors influencing detection of the federally endangered Diamond Darter Crystallaria cincotta: Implications for long-term monitoring strategies

Population monitoring is an essential component of endangered species recovery programs. The federally endangered Diamond Darter Crystallaria cincotta is in need of an effective monitoring design to improve our understanding of its distribution and track population trends. Because of their small size, cryptic coloration, and nocturnal behavior, along with limitations associated with current sampling methods, individuals are difficult to detect at known occupied sites. Therefore, research is needed to determine if survey efforts can be improved by increasing probability of individual detection. The primary objective of this study was to determine if there are seasonal and diel patterns in Diamond Darter detectability during population surveys. In addition to temporal factors, we also assessed five habitat variables that might influence individual detection. We used N -mixture models to estimate site abundances and relationships between covariates and individual detectability and ranked models using Akaike's information criteria. During 2015 three known occupied sites were sampled 15 times each between May and Oct. The best supported model included water temperature as a quadratic function influencing individual detectability, with temperatures around 22 C resulting in the highest detection probability. Detection probability when surveying at the optimal temperature was approximately 6% and 7.5% greater than when surveying at 16 C and 29 C, respectively. Time of Night and day of year were not strong predictors of Diamond Darter detectability. The results of this study will allow researchers and agencies to maximize detection probability when surveying populations, resulting in greater monitoring efficiency and likely more precise abundance estimates.

The American Midland Naturalist↗

USGS2021

Breeding season space use by lesser prairie-chickens (Tympanuchus Pallidicinctus) varies among ecoregions and breeding stages

Large-scale declines of grassland ecosystems in the conterminous United States since European settlement have led to substantial loss and fragmentation of lesser prairie-chicken ( Tympanuchus pallidicinctus ) habitat and decreased their occupied range and population numbers by ∼85%. Breeding season space use is an important component of lesser prairie-chicken conservation, because it could affect both local carrying capacity and population dynamics. Previous estimates of breeding season space use are largely limited to one of the four currently occupied ecoregions, but potential extrinsic drivers of breeding space use, such as landscape fragmentation, vegetation structure and composition, and density of anthropogenic structures, can show large spatial variation. Moreover, habitat needs vary greatly among the lekking/prelaying, nesting, brood-rearing, and postbreeding stages of the breeding season, but space use by female lesser prairie-chickens during these stages remain relatively unclear. We tested whether home range area and daily displacement (the net distance between the first and last location of each day) of female lesser prairie-chickens varied among ecoregions and breeding stages at four study sites in Kansas and Colorado, U.S.A., representing three of the four currently occupied ecoregions. We equipped females with very-high-frequency (VHF) or Global Positioning System (GPS) transmitters, and estimated home range area with kernel density estimators or biased random bridge models, respectively. Across all ecoregions, breeding season home range area averaged 190.4 ha (±19.1 ha se ) for birds with VHF and 283.6 ha (±23.1 ha) for birds with GPS transmitters, whereas daily displacement averaged 374.8 m (±14.3 m). Average home range area and daily displacement of bird with GPS transmitters were greater in the Short-Grass Prairie/ Conservation Reserve Program Mosaic and Sand Sagebrush Prairie Ecoregions compared to sites in the Mixed-Grass Prairie Ecoregion. Home range area and daily displacement were greatest during lekking/prelaying and smallest during the brood-rearing stage, when female movements were restricted by mobility of chicks. Ecoregion- and breeding stage-specific estimates of space use by lesser prairie-chickens will help managers determine the spatial configuration of breeding stage-specific habitat on the landscape. Furthermore, ecoregion- and breeding stage-specific estimates are crucial when estimating the amount of breeding habitat needed for lesser prairie-chicken populations to persist.

Colorado↗