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At least 235 records · Page 13Linked to original sources

USGS2023

Keeping the heat on: Weighted surveillance for Chytrid fungus (Batrachochytirum dendrobatidis) in Dixie Valley toads (Anaxyrus [= Bufo] williamsi)

Introduced fungal pathogens have caused declines and extinctions of naïve wildlife populations across vertebrate classes. Consequences of introduced pathogens to hosts with small ranges might be especially severe because of limited redundancy to rescue populations and lower abundance that may limit the resilience of populations to perturbations like disease introduction. As a complement to biosecurity measures to prevent the spread of pathogens, surveillance programs may enable early detection of pathogens, when management actions to limit the effects of pathogens on naïve hosts might be most beneficial. We analyzed surveillance data for the endangered and narrowly endemic Dixie Valley toad ( Anaxyrus [= Bufo ] williamsi ) from two time periods (2011–2014 and 2019–2021) to estimate the minimum detectable prevalence of the amphibian fungal pathogen Batrachochytrium dendrobatidis ( Bd ). We assessed if detection efficiency could be improved by using samples from both Dixie Valley toads and co-occurring introduced American bullfrogs ( Lithobates catesbeianus ) and literature-derived surveillance weights. We further evaluated a weighted surveillance design to increase the efficiency of surveillance efforts for Bd within the toad’s small (<6 km 2 ) range. We found that monitoring adult and larval American bullfrogs would probably detect Bd more efficiently than monitoring Dixie Valley toads alone. Given that no Bd was detected, minimum detectable prevalence of Bd was <3% in 2011–2014, and <5% (Dixie Valley toads only) and <10% (American bullfrogs only) in 2019–2021. Optimal management for Bd depends on the mechanisms underlying its apparent absence from the range of Dixie Valley toads, but a balanced surveillance scheme that includes sampling American bullfrogs to increase the likelihood of detecting Bd , and adult Dixie Valley toads to ensure broad spatial coverage where American bullfrogs do not occur, would probably result in efficient surveillance, which might permit timely management of Bd if it is detected.

Journal of Wildlife Diseases↗

USGS2009

The observed relationship between wave conditions and beach response, Ocean Beach, San Francisco, CA

Understanding how sandy beaches respond to storms is critical for effective sediment management and developing successful erosion mitigation efforts. However, only limited progress has been made in relating observed beach changes to wave conditions, with one of the major limiting factors being the lack of temporally dense beach topography and nearshore wave data in most studies. This study uses temporally dense beach topographic and offshore wave data to directly link beach response and wave forcing with generally good results. Ocean Beach is an open coast high-energy sandy beach located in San Francisco, CA, USA. From April 2004 through the end of 2008, 60 three-dimensional topographic beach surveys were conducted on approximately a monthly basis, with more frequent “short-term surveys during the winters of 2005-06 and 2006-07. Shoreline position data from the short-term surveys show good correlation with offshore wave height, period, and direction averaged over several days prior to the survey (mean R*=0.54 for entire beach). There is, however, considerable alongshore variation in model performance, with R- values ranging from 0.81 to 0.19 for individual sections of the beach. After wave height, the direction of wave approach was the most important factor in determining the response of the shoreline, followed by wave period. Our results indicate that an empirical predictive model of beach response to wave conditions at Ocean Beach is possible with frequent beach mapping and wave data, and that such a model could be useful to coastal managers.

California↗

USGS2013

Incorporating detection probability into northern Great Plains pronghorn population estimates

Pronghorn ( Antilocapra americana ) abundances commonly are estimated using fixed-wing surveys, but these estimates are likely to be negatively biased because of violations of key assumptions underpinning line-transect methodology. Reducing bias and improving precision of abundance estimates through use of detection probability and mark-resight models may allow for more responsive pronghorn management actions. Given their potential application in population estimation, we evaluated detection probability and mark-resight models for use in estimating pronghorn population abundance. We used logistic regression to quantify probabilities that detecting pronghorn might be influenced by group size, animal activity, percent vegetation, cover type, and topography. We estimated pronghorn population size by study area and year using mixed logit-normal mark-resight (MLNM) models. Pronghorn detection probability increased with group size, animal activity, and percent vegetation; overall detection probability was 0.639 (95% CI = 0.612–0.667) with 396 of 620 pronghorn groups detected. Despite model selection uncertainty, the best detection probability models were 44% (range = 8–79%) and 180% (range = 139–217%) greater than traditional pronghorn population estimates. Similarly, the best MLNM models were 28% (range = 3–58%) and 147% (range = 124–180%) greater than traditional population estimates. Detection probability of pronghorn was not constant but depended on both intrinsic and extrinsic factors. When pronghorn detection probability is a function of animal group size, animal activity, landscape complexity, and percent vegetation, traditional aerial survey techniques will result in biased pronghorn abundance estimates. Standardizing survey conditions, increasing resighting occasions, or accounting for variation in individual heterogeneity in mark-resight models will increase the accuracy and precision of pronghorn population estimates.

Journal of Wildlife Management↗

USGS1975

Long-term effects of 4-aminopyridine exposure to birds and fish

The avian frightening agent, 4-aminopyridine (4AP), was tested on five avian and two fish species to assess the effects of long-term 4AP exposure to nontarget vertebrates. Adult bobwhites ( Colinus virginianus ), mourning doves ( Zenaida macroura ), and ring-necked pheasants ( Phasianus colchicus ) were fed diets containing 3 percent 4AP-treated cracked corn diluted with various ratios of untreated corn for 7 to 35 days. Minimum dilution ratios that produced more than 50 percent mortality were 1:29 for bobwhites and 1:99 for doves. Mortality caused by 4AP could not be determined for pheasants because of their inability to subsist only on corn during the test periods. LCso's were determined for doves (316 ppm) and coturnix quail ( Coturnix coturnix ) (479 ppm) fed exclusively on uniformly treated laboratory rations for 28 to 40 days. Starlings ( Sturnus vulgaris ) treated by gavage daily for 25 days with 1.78 mg/kg 4AP showed no intoxication symptoms. Mortality in all avian species appeared to be the result of acute poisoning, and no evidence of cumulative toxicity was noted in species fed uniformly-treated rations. In 96-hour static tests, channel catfish ( Ictalurus punctatus ) and bluegill (Lepomis macrochirus) showed increasing sensitivity to 4AP with time in test waters ranging from very soft to very hard and from 12 to 22 C. The 96-hour LC 50 's for both species ranged from 2.43 to 7.56 mg/liter (ppm). Toxicity appeared to decrease with increasing water temperatures but was generally unaffected by water hardness. On the basis of the data presented, and the currently registered application rate for 4AP in agricultural crops (0.34 g/ha), long-term hazards to nontarget wildlife were judged to be minimal.

Colorado↗

USGS1997

Body-mass, survival, and pairing consequences of winter-diet restriction in wood ducks

We conducted feeding experiments with captive, wild-strain wood ducks ( Aix sponsa ) during winters 1990-91 and 1991-92 to test effects of increasing levels of food restriction on body mass dynamics, mortality, and pair formation. Male and female wood ducks fed restricted diets (i.e., 5, 10, 15, or 20% less food [g] than consumed on the previous day by a control group fed ad libitum) weighed less ( P ≤ 0.037) than birds fed ad libitum; those on 15 and 20% restricted diets weighed least. Increased mortality and decreased pair formation occurred only within the 20% restricted group ( P ≤ 0.049). We concluded that food restriction ranging between 15 and 20% of ad libitum intake may signify a threshold above which survival and reproduction of captive wood ducks may be impaired. Because energy costs of free living are greater than in captivity, a lower threshold may exist for wild wood ducks. Research is needed to validate the threshold theory for free-ranging wood ducks and other waterfowl, and to evaluate its potential application for conservation of winter foraging habitat. Conservation of bottomland hardwood ecosystems, which provide important foraging habitat for migrating and wintering wood ducks, should be encouraged to prevent potential negative effects on wood duck life-cycle events.

Mississippi↗

USGS2015

A case study of assigning conservation value to dispersed habitat units for conservation planning

Resource managers are increasingly tasked with developing habitat conservation plans in the face of numerous, sometimes competing, objectives. These plans must often be implemented across dispersed habitat conservation units that may contribute unequally to overall conservation objectives. Using U.S. Fish and Wildlife Service waterfowl production areas (WPA) in western Minnesota as our conservation landscape, we develop a landscape-scale approach for evaluating the conservation value of dispersed habitat conservation units with multiple conservation priorities. We evaluated conservation value based on a suite of variables directly applicable to conservation management practices, thus providing a direct link between conservation actions and outcomes. We developed spatial models specific to each of these conservation objectives and also developed two freely available prioritization tools to implement these analyses. We found that some WPAs provided high conservation value across a range of conservation objectives, suggesting that managing these specific areas would achieve multiple conservation goals. Conversely, other WPAs provided low conservation value for some objectives, suggesting they would be most effectively managed for a distinct set of specific conservation goals. Approaches such as ours provide a direct means of assessing the conservation value of dispersed habitat conservation units and could be useful in the development of habitat management plans, particularly when faced with multiple conservation objectives.

Journal of Conservation Planning↗

USGS2018

Is barotrauma an important factor in the discard mortality of Yellow Perch?

In physoclistous fishes, barotrauma caused by rapid decompression during capture may be an important source of fishing mortality that is unquantified for some fisheries. We developed a predictive logistic model for barotrauma incidence in Yellow Perch Perca flavescens and applied this model to Ohio's recreational and commercial fisheries in Lake Erie where fisheries managers implicitly consider discard mortality to be negligible in current stock assessment. As expected, capture depth explained most of the variation in incidence, with comparatively small effects of season, sex, and size categories. Measurements of whole body and gonad density provided limited explanation for the categorical effects. Both fisheries spanned a range of depths (7.6 to 16.8 m) that corresponded to a broad range of barotrauma incidence (13 to 74%). Using a recent example, we estimated that additional fishing mortality due to barotrauma in discards was approximately six-fold higher in the commercial than recreational fishery. Overall, this additional mortality was <1% of lake-wide population size estimates. Thus, the assumption that all discarded Yellow Perch survive is unlikely to result in a detectable bias in population estimates. One caveat is that we still do not understand how strong year-classes might influence discard mortality via increased discard rate and barotrauma incidence for small fish.

Journal of Fish and Wildlife Management↗

USGS2022

Influence of seasonal extreme flows on Brook Trout recruitment

Populations of Brook Trout Salvelinus fontinalis exhibit large variation in annual recruitment (abundance of young of the year [age 0]), which is likely a product of density-dependent and density-independent factors. Quantifying the importance of each of these mechanisms in regulating Brook Trout recruitment would be valuable to managers that are responsible for the conservation of this iconic species throughout its native range. We analyzed a time series of age-0 and adult Brook Trout density data collected from 10 streams in the Sinnemahoning Creek watershed, north-central Pennsylvania (2010–2019), using Bayesian hierarchical modeling to partition the density-dependent effects of adult density and the density-independent effects of elevated streamflow on Brook Trout recruitment. Multiple models were examined, and the top-ranked model showed that Brook Trout recruitment followed a Ricker stock–recruitment relationship, with annual recruitment negatively influenced by maximum streamflow during the spring season (March–April). This model will be useful in predicting future variation in Brook Trout recruitment under climate change scenarios in which the frequency and intensity of high-flow events are expected to increase.

Pennsylvania↗

USGS2011

Spatiotemporal distribution and population characteristicsof a nonnative lake trout population, with implications for suppression

We evaluated the distribution and population characteristics of nonnative lake trout Salvelinus namaycush in Lake McDonald,Glacier National Park,Montana, to provide biological data in support of a potential suppression program. Using ultrasonic telemetry, we identified spatial and temporal distribution patterns by tracking 36 adult lake trout (1,137 relocations). Lake trout rarely occupied depths greater than 30 m and were commonly located in the upper hypolimnion directly below the metalimnion during thermal stratification. After breakdown of themetalimnion in the fall, lake trout primarily aggregated at two spawning sites. Lake trout population characteristics were similar to those of populations within the species' native range. However, lake trout in Lake McDonald exhibited lower total annual mortality (13.2%), latermaturity (age 12 formales, age 15 for females), lower body condition, and slower growth than are typically observed in the southern extent of their range. These results will be useful in determining where to target suppression activities (e.g., gillnetting, trap-netting, or electrofishing) and in evaluating responses to suppression efforts. Similar evaluations of lake trout distribution patterns and population characteristics are recommended to increase the likelihood that suppression programs will succeed. ?? American Fisheries Society 2011.

North American Journal of Fisheries Management↗

USGS2016

Using scenarios to assess possible future impacts of invasive species in the Laurentian Great Lakes

The expected impacts of invasive species are key considerations in selecting policy responses to potential invasions. But predicting the impacts of invasive species is daunting, particularly in large systems threatened by multiple invasive species, such as North America’s Laurentian Great Lakes. We developed and evaluated a scenario-building process that relied on an expert panel to assess possible future impacts of aquatic invasive species on recreational fishing in the Great Lakes. To maximize its usefulness to policy makers, this process was designed to be implemented relatively rapidly and consider a range of species. The expert panel developed plausible, internally-consistent invasion scenarios for 5 aquatic invasive species, along with subjective probabilities of those scenarios. We describe these scenarios and evaluate this approach for assessing future invasive species impacts. The panel held diverse opinions about the likelihood of the scenarios, and only one scenario with impacts on sportfish species was considered likely by most of the experts. These outcomes are consistent with the literature on scenario building, which advocates for developing a range of plausible scenarios in decision making because the uncertainty of future conditions makes the likelihood of any particular scenario low. We believe that this scenario-building approach could contribute to policy decisions about whether and how to address the possible impacts of invasive species. In this case, scenarios could allow policy makers to narrow the range of possible impacts on Great Lakes fisheries they consider and help set a research agenda for further refining invasive species predictions.

Great Lakes, Lake Superior, Lake Huron, Lake Michi↗

USGS2019

Occupancy Patterns of Breeding American Black Ducks

Occupancy patterns can assist with the determination of habitat limitation during breeding or wintering periods and can help guide population and habitat management efforts. American black ducks ( Anas rubripes ; black ducks) are thought to be limited by habitat and food availability during the winter, but breeding sites may also limit the size or growth potential of the population. The Canadian Wildlife Service conducts an annual breeding waterfowl survey that we used to explore the hypothesis that black duck carrying capacity is limited by wetlands available for breeding in Québec, Canada. We applied single‐visit, multi‐species occupancy models to the 1990–2015 population survey data to determine if there was evidence the black duck population was limited by breeding habitat. Using a dynamic (multi‐season) occupancy modeling approach, we estimated latent occupancy (occupancy accounting for imperfect detection) of black ducks and then used latent occupancy estimates to derive occupancy, colonization, and extirpation rates. We jointly modeled the occupancy dynamics of black ducks and other duck species in wetlands where both species were present. Throughout the duration of the survey, 44% of wetlands were never observed to be occupied by black ducks. Occupancy models showed wetland size was positively associated with occupancy at the first time step (initial occupancy) and colonization. All 2‐species models indicated initial black duck occupancy, persistence (continued occupancy), and colonization were positively associated with the presence of a second species. Colonization rate over the 26‐year period ranged from 7% to 27% across all models. Extirpation rates were similar and were constant through time within each model. Low occupancy rates, combined with approximately equal colonization and extirpation rates, suggest there are available wetlands for breeding black ducks in their core breeding area. If breeding habitats are not saturated, this suggests migration or wintering areas may be more limiting to black duck population abundance.

Ontario, Quebec↗

USGS2013

SPARROW models used to understand nutrient sources in the Mississippi/Atchafalaya River Basin

Nitrogen (N) and phosphorus (P) loading from the Mississippi/Atchafalaya River Basin (MARB) has been linked to hypoxia in the Gulf of Mexico. To describe where and from what sources those loads originate, SPAtially Referenced Regression On Watershed attributes (SPARROW) models were constructed for the MARB using geospatial datasets for 2002, including inputs from wastewater treatment plants (WWTPs), and calibration sites throughout the MARB. Previous studies found that highest N and P yields were from the north-central part of the MARB (Corn Belt). Based on the MARB SPARROW models, highest N yields were still from the Corn Belt but centered over Iowa and Indiana, and highest P yields were widely distributed throughout the center of the MARB. Similar to that found in other studies, agricultural inputs were found to be the largest N and P sources throughout most of the MARB: farm fertilizers were the largest N source, whereas farm fertilizers, manure, and urban inputs were dominant P sources. The MARB models enable individual N and P sources to be defined at scales ranging from SPARROW catchments (∼50 km 2 ) to the entire area of the MARB. Inputs of P from WWTPs and urban areas were more important than found in most other studies. Information from this study will help to reduce nutrient loading from the MARB by providing managers with a description of where each of the sources of N and P are most important, thus providing a basis for prioritizing management actions and ultimately reducing the extent of Gulf hypoxia.

Mississippi/atchafalaya River Basin↗

USGS2025

Timing of Steller’s Eider remigial molt has delayed over 26-year span

The Steller’s Eider is a sea duck that uses specific molting areas in lagoons in southwest Alaska, and these molting populations have declined in recent decades. The annual flight feather molt is a significant stage in avian life-history. The focus of this study was to characterize the phenology of Steller’s Eider flight feather molt timing and explore if molt timing is (1) earlier, (2) remained unchanged, or (3) is delayed. We developed a flight feather growth function throughout molt using data from captive birds. We used measurements from free-ranging birds over a 26-year period to investigate variation in molt start dates among sexes, years, and locations. Results indicate that fall molt timing has delayed over 26 years for Steller’s Eiders in our study area. We speculate that drivers of observed change in timing may be related to changes in seasonal Arctic environmental conditions. Our findings can be used by managers to inform timing of population surveys.

Alaska↗

USGS2017

Deepwater Program: Lophelia II, continuing ecological research on deep-sea corals and deep-reef habitats in the Gulf of Mexico

The deep sea is a rich environment composed of diverse habitat types. While deep-sea coral habitats have been discovered within each ocean basin, knowledge about the ecology of these habitats and associated inhabitants continues to grow. This report presents information and results from the Lophelia II project that examined deep-sea coral habitats in the Gulf of Mexico. The Lophelia II project focused on Lophelia pertusa habitats along the continental slope, at depths ranging from 300 to 1,000 meters. The chapters are authored by several scientists from the U.S. Geological Survey, National Oceanic and Atmospheric Administration, University of North Carolina Wilmington, and Florida State University who examined the community ecology (from microbes to fishes), deep-sea coral age, growth, and reproduction, and population connectivity of deep-sea corals and inhabitants. Data from these studies are presented in the chapters and appendixes of the report as well as in journal publications. This study was conducted by the Ecosystems Mission Area of the U.S. Geological Survey to meet information needs identified by the Bureau of Ocean Energy Management.

Gulf of Mexico↗

USGS2013

Golden eagle population trends in the western United States: 1968-2010

In 2009, the United States Fish and Wildlife Service promulgated permit regulations for the unintentional lethal take (anthropogenic mortality) and disturbance of golden eagles (Aquila chrysaetos). Accurate population trend and size information for golden eagles are needed so agency biologists can make informed decisions when eagle take permits are requested. To address this need with available data, we used a log-linear hierarchical model to average data from a late-summer aerial-line-transect distance-sampling survey (WGES) of golden eagles in the United States portions of Bird Conservation Region (BCR) 9 (Great Basin), BCR 10 (Northern Rockies), BCR 16 (Southern Rockies/Colorado Plateau), and BCR 17 (Badlands and Prairies) from 2006 to 2010 with late-spring, early summer Breeding Bird Survey (BBS) data for the same BCRs and years to estimate summer golden eagle population size and trends in these BCRs. We used the ratio of the density estimates from the WGES to the BBS index to calculate a BCR-specific adjustment factor that scaled the BBS index (i.e., birds per route) to a density estimate. Our results indicated golden eagle populations were generally stable from 2006 to 2010 in the 4 BCRs, with an estimated average rate of population change of −0.41% (95% credible interval [CI]: −4.17% to 3.40%) per year. For the 4 BCRs and years, we estimated annual golden eagle population size to range from 28,220 (95% CI: 23,250–35,110) in 2007 to 26,490 (95% CI: 21,760–32,680) in 2008. We found a general correspondence in trends between WGES and BBS data for these 4 BCRs, which suggested BBS data were providing useful trend information. We used the overall adjustment factor calculated from the 4 BCRs and years to scale BBS golden eagle counts from 1968 to 2005 for the 4 BCRs and for 1968 to 2010 for the 8 other BCRs (without WGES data) to estimate golden eagle population size and trends across the western United States for the period 1968 to 2010. In general, we noted slightly declining trends in southern BCRs and slightly increasing trends in northern BCRs. However, we estimated the average rate of golden eagle population change across all 12 BCRs for the period 1968–2010 as +0.40% per year (95% CI = −0.27% to 1.00%), suggesting a stable population. We also estimated the average rate of population change for the period 1990–2010 was +0.5% per year (95% CI = −0.33% to 1.3%). Our annual estimates of population size for the most recent decade range from 31,370 (95% CI: 25,450–39,310) in 2004 to 33,460 (95% CI: 27,380–41,710) in 2007. Our results clarify that golden eagles are not declining widely in the western United States. © 2013 The Wildlife Society.

Arizona;California;Colorado;Idaho;Iowa;Kansas;Minn↗

USGS1988

Effects of variation in flow on distribution of northern squawfish ( Ptychocheilus oregonensis ) below McNary Dam on the Columbia River

The movements of 23 northern Squawfish Ptychocheilus oregonensis were monitored by radiotelemetry below a Columbia River hydroelectric dam during the out-migration of juvenile anadromous salmonids in 1984 and 1985. The work was done as part of a study to relate predator abundances and distribution to juvenile salmonid mortalities associated with dams. Northern Squawfish remained in protected shoreline areas in spring and early summer, when discharge rates were high, but moved close to the dam and the juvenile bypass outflow area in mid to late summer, when discharge rates were low. Trends in northern Squawfish movements were similar during abrupt changes in discharge rate. During short-term closures of the spillway, when flow patterns were abruptly changed, four of five northern Squawfish moved out of protected areas and into the main river channel. Surface water velocities at 81 locations occupied by radio-tagged northern Squawfish in June to August 1985 ranged from 0 to 70 cm/s (mean, 24.5 cm/s). No preference within this range was evident, but the fish seemingly avoided areas of high current velocity, because they did not move into a substantial portion of the tailrace where water velocities exceeded 100 cm/s. Modification of structures to maintain high water velocities around bypass outflow areas should reduce potential predation on juvenile salmonids by northern squawfish.

Oregon, Washington↗

USGS1973

Summer behavior of immature radio-equipped woodcock in central Maine

The behavior of 15 immature American woodcock ( Philohela minor ) was studied in central Maine during the summers of 1969 and 1970 using radiotelemetry. The monitored birds used a variety of nocturnal sites including old fields, bogs, powerlines, highway medians, woods roads, and fore clearings. Old fields were occupied more often than any other type of opening. Second growth-hardwoods, alders, hardwood-conifers, and conifers were utilized as diurnal cover. Diurnal locations of radio-equipped woodcock averaged 15 m from major breaks in the forest canopy. Four birds were monitored continuously during the day and night to determine periods of activity. Although the birds were active throughout the day, very little activity was recorded after they moved to nocturnal sites. No apparent difference was found in the daily patterns of movement between immature male and female woodcock. Crepuscular movements between diurnal covers and nocturnal areas averaged 332 m. A composite summer range for the 15 woodcock during 183 woodcock-days was 1060 hectares. The data suggest that immature woodcock are quite mobile during the summer and utilize most of the forest openings occurring within 1-3 km of good nesting habitat. Most of these openings are also used for singing grounds by males in the spring.

Maine↗

USGS2016

Life history characteristics and vital rates of Yellowstone Cutthroat Trout in two headwater basins

The Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri is native to the Rocky Mountains and has declined in abundance and distribution as a result of habitat degradation and introduced salmonid species. Many of its remaining strongholds are in headwater basins with minimal human disturbances. Understanding the life histories, vital rates, and behaviors of Yellowstone Cutthroat Trout within headwater stream networks remains limited yet is critical for effective management and conservation. We estimated annual relative growth in length and weight, annual survival rates, and movement patterns of Yellowstone Cutthroat Trout from three tributaries of Spread Creek, Wyoming, and two tributaries of Shields River, Montana, from 2011 through 2013 using PIT tag antennas within a mark–recapture framework. Mean annual growth rates varied among tributaries and size-classes, but were slow compared with populations of Yellowstone Cutthroat Trout from large, low-elevation streams. Survival rates were relatively high compared with those of other Cutthroat Trout subspecies, but we found an inverse relationship between survival and size, a pattern contrary to what has been reported for Cutthroat Trout in large streams. Mean annual survival rates ranged from 0.32 (SE = 0.04) to 0.68 (SE = 0.05) in the Spread Creek basin and from 0.30 (SE = 0.07) to 0.69 (SE = 0.10) in the Shields River basin. Downstream movements from tributaries were substantial, with as much as 26.5% of a tagging cohort leaving over the course of the study. Integrating our growth, survival, and movement results demonstrates the importance of considering strategies to enhance headwater stream habitats and highlights the importance of connectivity with larger stream networks.

North American Journal of Fisheries Management↗