Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Report Series”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,693 records · Page 94Linked to original sources
USGS2013

Estimating abundance of the Southern Hudson Bay polar bear subpopulation using aerial surveys, 2011 and 2012

The Southern Hudson Bay (SH) polar bear subpopulation occurs at the southern extent of the species’ range. Although capture-recapture studies indicate that abundance remained stable between 1986 and 2005, declines in body condition and survival were documented during the period, possibly foreshadowing a future decrease in abundance. To obtain a current estimate of abundance, we conducted a comprehensive line transect aerial survey of SH during 2011–2012. We stratified the study site by anticipated densities and flew coastal contour transects and systematically spaced inland transects in Ontario and on Akimiski Island and large offshore islands in 2011. Data were collected with double observer and distance sampling protocols. We also surveyed small islands in Hudson Bay and James Bay and flew a comprehensive transect along the Québec coastline in 2012. We observed 667 bears in Ontario and on Akimiski Island and nearby islands in 2011, and we sighted 80 bears on offshore islands during 2012. Mark-recapture distance sampling and sightresight models yielded a model-averaged estimate of 868 (SE: 177) for the 2011 study area. Our estimate of abundance for the entire SH subpopulation (951; SE: 177) suggests that abundance has remained unchanged. However, this result should be interpreted cautiously because of the methodological differences between historical studies (physical capture) and this survey. A conservative management approach is warranted given the previous increases in the duration of the ice-free season, which are predicted to continue in the future, and previously documented declines in body condition and vital rates.

Hudson Bay↗
USGS1994

Suspended sediment and stream discharge in Bloody Run and Sny Magill watershed, water year 1992

Hydrologic data were collected in the Bloody Run and Sny Magill watersheds in Clayton County, Iowa during the 1992 Water Year (October 1, 1991 to September 30, 1992) to provide data on suspended sediment and stream discharge from these watersheds. Suspended-sediment samples were collected daily during normal flow and several times during rainstorms. Stream stage was recorded continuously and stream-discharge measurements were made monthly to develop a stage-discharge relation. Data on drainage-basin morphology and precipitation were quantified to help understand the variability in sediment and stream discharge. The total suspended-sediment discharge for Water Year 1992 was 2,720 tons at site BR1 on Bloody Run and 1,940 tons at site SN1 on Sny Magill Creek The daily median suspended-sediment discharge was 1.1 tons at both sites BR1 and SN1. The maximum daily mean stream discharge (205 cubic feet per second) at site BR1 on Bloody Run occurred on November 1, 1991. The median daily discharge at BR1 for the 1992 Water year was 24 cubic feet per second or 0.70 cubic feet per second per square mile (ft 3 /s/mi 2 ). The maximum daily mean stream discharge at site SN1 on Sny Magill Creek was 90 cubic feet per second which occurred on April 20, 1992. The median daily discharge at site SN1 for the 1992 Water Year was 15 cubic feet per second or 0.54 ft 3 /s/mi 2 .

Iowa↗
USGS1965

Developing a state water plan: Ground-water conditions in Utah, spring of 1965

This report is the second in a series of annual reports that describe ground-water conditions in Utah. It includes individual discussions of the most important areas of ground-water withdrawal in the State for the claendar year of 1964. Water-level fluctuations, however, are described for the period spring 1964 through spring 1965. The report was prepared cooperatively by the U.S. Geological Survey and the Utah Water and Power Board. Many of the data used in the preparation of the report were collected by the Geological Survey in cooperation with the Utah State Engineer. Some of the data for the number of wells constructed during 1964 were prepared by digital computer from the Utah Resources Information System data bank, University of Utah, using records that were compiled from the files of the Utah State Engineer.

Utah↗
USGS2016

Establishing links between streamflow and ecological integrity in the Sudbury River (Northeastern U.S.)

With increased pressure from a growing human population, managers are challenged to understand how novel disturbances (e.g., climate change, increased water withdrawals, urbanization) may affect natural resources. The Sudbury River is a National Wild and Scenic River located in suburban Boston, Massachusetts (Northeastern US) with myriad impairments (e.g., mainstem impoundments, withdrawals, and urbanization) that is under increasing pressure from hydrologic alteration. We sampled fish, mussel, and macroinvertebrate assemblages in the Sudbury River and used species traits to investigate potential effects of past and future flow alteration on biota. Analysis of 33 years of stream gage data indicates continued hydrologic alteration of the Sudbury River, likely related to increased urbanization and water withdrawals over that time. These changes include a roughly 200% increase in rise rates of flows, an approximate 65% decrease in 1-day minimum flows, and a trend towards increasing high flow pulse counts. Biotic sampling in summer of 2014 demonstrated that the Sudbury River is now dominated by generalist species. Of five mussel species sampled, all are generalists in their habitat requirements. Though one mussel species of special concern was sampled, the most abundant species collected were the widespread Eastern elliptio (58%) and Eastern lampmussel (40%). We used the target fish community (TFC) model to assess the degree to which the fish assemblage deviated from that expected for a river with similar zoogeographic and physical features. Overall, the current community has a 22.7% similarity to the TFC. Of the four fluvial specialist species present in the TFC, only fallfish was sampled in our study. While the TFC showed that the historical assemblage was likely dominated by fluvial specialist and fluvial dependent species, the current assemblage is overwhelmingly dominated by macrohabitat generalists (90.6% of fishes sampled). These results are consistent with other studies that show shifts in assemblages from fluvial specialists to habitat generalists with hydrologic alteration. If the current trends continue, it is likely that biotic assemblages will experience increasing pressure from hydrologic alteration. While hydrologic alteration is likely impacting biotic assemblages in the Sudbury River, other factors such as high temperatures, low dissolved oxygen, high nutrients, low availability of high-quality habitat, and poor habitat connectivity may also be negatively impacting biotic assemblages. Comparisons to other rivers and a complete longitudinal habitat survey could help to identify availability of unique habitats and representativeness of this study. While this study suggests impacts of flow on biota, future studies with quantitative, habitat-specific sampling during different flow levels could help to directly identify links between hydrologic alteration and biotic impairment in the Sudbury River.

Massachussetts↗
USGS1978

A paleolimnological comparison of Burntside and Shagawa Lakes, northeastern Minnesota

The paleolimnological records of Burntside and Shagawa Lakes in northeastern Minnesota reveal that these two adjacent lakes have been limnologically distinct for many years prior to the late 19th century activities of white men that polluted Shagawa Lake. Although both lakes occur within the same vegetation type and share much of their water, the diatom stratigraphy of their bottom sediments indicates that Burntside Lake was less productive in its natural state than Shagawa Lake. The causes for this natural difference are not clearly known, but differences in relative size of drainage area and in bedrock geology may he responsible. Intensive white settlement around Shagawa Lake beginning in 1866 supplied nutrients that increased its productivity and finally supported the massive blooms of blue-green algae that characterize culturally eutrophic lakes. Burntside Lake was spared such intensive eutrophication, but its diatom record shows that nutrients derived from shoreside recreational cabins and related construction activity are increasing the lake's productivity. The results of this study show that paleolimnological studies may provide better comparative information for lake rehabilitation programs than do biological and chemical analyses of contemporary unpolluted water bodies.

Minnesota↗
USGS2016

Estimating black bear density in New Mexico using noninvasive genetic sampling coupled with spatially explicit capture-recapture methods

During the 2004–2005 to 2015–2016 hunting seasons, the New Mexico Department of Game and Fish (NMDGF) estimated black bear abundance (Ursus americanus) across the state by coupling density estimates with the distribution of primary habitat generated by Costello et al. (2001). These estimates have been used to set harvest limits. For example, a density of 17 bears/100 km2 for the Sangre de Cristo and Sacramento Mountains and 13.2 bears/100 km2 for the Sandia Mountains were used to set harvest levels. The advancement and widespread acceptance of non-invasive sampling and mark-recapture methods, prompted the NMDGF to collaborate with the New Mexico Cooperative Fish and Wildlife Research Unit and New Mexico State University to update their density estimates for black bear populations in select mountain ranges across the state. We established 5 study areas in 3 mountain ranges: the northern (NSC; sampled in 2012) and southern Sangre de Cristo Mountains (SSC; sampled in 2013), the Sandia Mountains (Sandias; sampled in 2014), and the northern (NSacs) and southern Sacramento Mountains (SSacs; both sampled in 2014). We collected hair samples from black bears using two concurrent non-invasive sampling methods, hair traps and bear rubs. We used a gender marker and a suite of microsatellite loci to determine the individual identification of hair samples that were suitable for genetic analysis. We used these data to generate mark-recapture encounter histories for each bear and estimated density in a spatially explicit capture-recapture framework (SECR). We constructed a suite of SECR candidate models using sex, elevation, land cover type, and time to model heterogeneity in detection probability and the spatial scale over which detection probability declines. We used Akaike’s Information Criterion corrected for small sample size (AICc) to rank and select the most supported model from which we estimated density. We set 554 hair traps, 117 bear rubs and collected 4,083 hair samples. We identified 725 (367 M, 358 F) individuals; the sex ratio for each study area was approximately equal. Our density estimates varied within and among mountain ranges with an estimated density of 21.86 bears/100 km2 (95% CI: 17.83 – 26.80) for the NSC, 19.74 bears/100 km2 (95% CI: 13.77 – 28.30) in the SSC, 25.75 bears/100 km2 (95% CI: 13.22 – 50.14) in the Sandias, 21.86 bears/100 km2 (95% CI: 17.83 – 26.80) in the NSacs, and 16.55 bears/100 km2 (95% CI: 11.64 – 23.53) in the SSacs. Overall detection probability for hair traps and bear rubs, combined, was low across all study areas and ranged from 0.00001 to 0.02. We speculate that detection probabilities were affected by failure of some hair samples to produce a complete genotype due to UV degradation of DNA, and our inability to set and check some sampling devices due to wildfires in the SSC. Ultraviolet radiation levels are particularly high in New Mexico compared to other states where NGS methods have been used because New Mexico receives substantial amounts of sunshine, is relatively high in elevation (1,200 m – 4,000 m), and is at a lower latitude. Despite these sampling difficulties, we were able to produce density estimates for New Mexico black bear populations with levels of precision comparable to estimated black bear densities made elsewhere in the U.S. Our ability to generate reliable black bear density estimates for 3 New Mexico mountain ranges is attributable to our use of a statistically robust study design and analytical method. There are multiple factors that need to be considered when developing future SECR-based density estimation projects. First, the spatial extent of the population of interest and the smallest average home range size must be determined; these will dictate size of the trapping array and spacing necessary between hair traps. The number of technicians needed and access to the study areas will also influence configuration of the trapping array. We believe shorter sampling occasions could be implemented to reduce degradation of DNA due to UV radiation; this might help increase amplification rates and thereby increase both the number of unique individuals identified and the number of recaptures, improving the precision of the density estimates. A pilot study may be useful to determine the length of time hair samples can remain in the field prior to collection. In addition, researchers may consider setting hair traps and bear rubs in more shaded areas (e.g., north facing slopes) to help reduce exposure to UV radiation. To reduce the sampling interval it will be necessary to either hire more field personnel or decrease the number of hair traps per sampling session. Both of these will enhance detection of long-range movement events by individual bears, increase initial capture and recapture rates, and improve precision of the parameter estimates. We recognize that all studies are constrained by limited resources, however, increasing field personnel would also allow a larger study area to be sampled or enable higher trap density. In conclusion, we estimated the density of black bears in 5 study areas within 3 mountains ranges of New Mexico. Our estimates will aid the NMDGF in setting sustainable harvest limits. Along with estimates of density, information on additional demographic rates (e.g., survival rates and reproduction) and the potential effects that climate change and future land use may have on the demography of black bears may also help inform management of black bears in New Mexico, and may be considered as future areas for research.

New Mexico↗
USGS2016

Evaluation and refinement of Guadalupe Bass conservation strategies to support adaptive management

Burbot Lota lota is the sole freshwater representative of the cod-like fishes and supports subsistence, commercial, and recreational fisheries worldwide above approximately 40° N. It is a difficult species to manage effectively due to its preference for deep-water habitats and spawning activity under the ice in winter. Like other gadiform fishes, Burbot use acoustic signaling as part of their mating system, and while the acoustic repertoire of the species has been characterized under artificial conditions (i.e., net pen suspended under ice in a natural lake), there has been no work to determine whether the species is as vocal in natural spawning aggregations. Our objective was to assess the feasibility of collecting and using acoustic data to characterize the spawning activity and locations of Burbot under field conditions. We recorded audio and video of Burbot spawning aggregations through holes drilled into the ice at known spawning grounds at Moyie Lake in British Columbia, Canada. Acoustic recordings (call counts and audiograms) were analyzed using Raven Pro v 1. 4 software. Acoustic behavior was also related to video data to determine how acoustic activity correlated to any observed spawning behavior. In general, wild Burbot spawning in Moyie Lake did not vocalize as frequently as counterparts spawning under artificial conditions. Further, Burbot vocalizations were not recorded in conjunction with spawning activity. While it may be feasible to use passive acoustic monitoring to locate Burbot spawning grounds and identify periods of activity, it does not seem to hold much promise for locating and quantifying spawning activity in real time.

Cooperator Science Series↗
USGS2016

Prioritizing landscapes for longleaf pine conservation

We developed a spatially explicit model and map, as a decision support tool (DST), to aid conservation agencies creating or maintaining open pine ecosystems. The tool identified areas that are likely to provide the greatest benefit to focal bird populations based on a comprehensive landscape analysis. We used NLCD 2011, SSURGO, and SEGAP data to map the density of desired resources for open pine ecosystems and six focal species of birds and 2 reptiles within the historic range of longleaf pine east of the Mississippi River. Binary rasters were created of sites with desired characteristics such as land form, hydrology, land use and land cover, soils, potential habitat for focal species, and putative source populations of focal species. Each raster was smoothed using a kernel density estimator. Rasters were combined and scaled to map priority locations for the management of each focal species. Species’ rasters were combined and scaled to provide maps of overall priority for birds and for birds and reptiles. The spatial data can be used to identify high priority areas for conservation or to compare areas under consideration for maintenance or creation of open pine ecosystems.

Cooperator Science Series↗
USGS2014

Restoration of Rio Grande cutthroat trout Oncorhynchus clarkii virginalis to the Mescalero Apache Reservation

Rio Grande Cutthroat trout Oncorhynchus clarkii virginalis (RGCT) represents the most southern subspecies of cutthroat trout, endemic to Rio Grande, Canadian, and Pecos basins of New Mexico and southern Colorado. The subspecies currently occupies less than 12% of its historic range. The Mescalero Apache Tribe has partnered with U.S. Geological Survey-New Mexico Cooperative Fish and Wildlife Research Unit, New Mexico State University, U.S. Fish and Wildlife Service, and New Mexico Department of Game and Fish to meet mutually shared goals of restoring and maintaining a Pecos strain of RGCT to Tribal lands. The goal of this project was to assess the suitability of the Rio Ruidoso within the Mescalero Apache Reservation to support a self-sustaining RGCT population by conducting a systematic and comprehensive survey. We conducted three surveys (fall 2010, spring 2011 and 2012) to characterize water quality, macroinvertebrate assemblages, fish communities, and physical habitat (stream size, channel gradient, channel substrate, habitat complexity, riparian vegetation cover and structure, migration barriers to movement). Seven-100 m reaches throughout three major tributaries of the Rio Ruidoso within the Tribal lands were sampled during baseflow conditions October 2010, May 2011, and June 2012. Despite the onset of severe drought in 2011, water quality, physical habitat, and fish populations revealed that the Rio Ruidoso and its three tributaries would most likely support a self-sustaining RGCT population. Pools were abundant (mean, 8.9 pools/100 m), instream woody debris was present (range, 3.8-45.6 pieces/100 m), and instream dataloggers revealed daily maximum stream temperatures rarely exceeded criteria established in New Mexico for coldwater fishes, however, presence of frazil and anchor ice may limit fish distribution in the winter. Aquatic macroinvertebrate samples revealed a community of benthic invertebrates reflective of high quality cool to cold water. Overall densities of brown trout, rainbow trout and brook trout were high (overall mean, 0.23 fish/m2) and in relatively good condition (range of mean relative weight, 84-117). Should the Mescalero Apache Tribe decide to introduce RGCT, prior to chemical treatment, a barrier placed below the confluence of Middle and South forks of the Rio Ruidoso would create approximately 12 km of perennial flow and help protect against invasion of non-native fishes. The North Fork of the Rio Ruidoso is not a good candidate for reintroduction because of easy access by the public to reintroduce non-native fishes into the watershed. Lastly, an annual, long-term monitoring program of RGCT would help document that there was no subsequent incursion of non-native fishes.

Cooperator Science Series↗
USGS2016

Identification of Neosho Smallmouth Bass (Micropterus dolomieu velox) stocks for possible introduction into Grand Lake, Oklahoma

Stocking black basses (Micropterus spp.) is a common practice used to increase angling opportunities in impoundments; however, when non-native black basses are introduced they often invade riverine habitats where they threaten the persistence of other fishes, including native black basses. Neosho Smallmouth Bass (M. dolomieu velox) is endemic to portions of the Ozark Highlands and Boston Mountains ecoregions and is threatened by introductions of non-native Smallmouth Bass (“SMB”) forms. Because of recent interest in stocking SMB into Grand Lake o’ the Cherokees, we assessed the suitability of local Neosho SMB populations as potential broodstock sources by assessing introgression with non-native SMB forms, as well as characterizing population structure and genetic diversity. The majority of Neosho SMB populations contained low, but non-negligible, genomic proportions of two genetically distinct non-native SMB forms. Introgression was highest in the Illinois River upstream of Lake Tenkiller, where Tennessee ‘lake strain’ SMB were stocked in the early 1990’s. We recovered three genetically distinct clusters of Neosho SMB at the uppermost hierarchical level of population structure: a distinct Illinois River cluster and two Grand River clusters that appear to naturally mix at some sites. Genetic diversity measures generally increased with stream size, and smaller populations with low diversity measures may benefit from immigration of novel genetic material. Overall, introgression with non-native SMB forms appears to pose a prominent threat to Neosho SMB; however, relatively intact populations of Neosho SMB exist in some Grand Lake o’ the Cherokees tributaries. Results could be used in developing a stocking program that promotes and sustains existing genetic diversity within and among Neosho SMB populations.

Cooperator Science Series↗
USGS2017

Using population models to evaluate management alternatives for Gulf Striped Bass

Interstate management of Gulf Striped Bass Morone saxatilis has involved a thirty-year cooperative effort involving Federal and State agencies in Georgia, Florida and Alabama (Apalachicola-Chattahoochee-Flint Gulf Striped Bass Technical Committee). The Committee has recently focused on developing an adaptive framework for conserving and restoring Gulf Striped Bass in the Apalachicola, Chattahoochee, and Flint River (ACF) system. To evaluate the consequences and tradeoffs among management activities, population models were used to inform management decisions. Stochastic matrix models were constructed with varying recruitment and stocking rates to simulate effects of management alternatives on Gulf Striped Bass population objectives. An age-classified matrix model that incorporated stock fecundity estimates and survival estimates was used to project population growth rate. In addition, combinations of management alternatives (stocking rates, Hydrilla control, harvest regulations) were evaluated with respect to how they influenced Gulf Striped Bass population growth. Annual survival and mortality rates were estimated from catch-curve analysis, while fecundity was estimated and predicted using a linear least squares regression analysis of fish length versus egg number from hatchery brood fish data. Stocking rates and stocked-fish survival rates were estimated from census data. Results indicated that management alternatives could be an effective approach to increasing the Gulf Striped Bass population. Population abundance was greatest under maximum stocking effort, maximum Hydrilla control and a moratorium. Conversely, population abundance was lowest under no stocking, no Hydrilla control and the current harvest regulation. Stocking rates proved to be an effective management strategy; however, low survival estimates of stocked fish (1%) limited the potential for population growth. Hydrilla control increased the survival rate of stocked fish and provided higher estimates of population abundances than maximizing the stocking rate. A change in the current harvest regulation (50% harvest regulation) was not an effective alternative to increasing the Gulf Striped Bass population size. Applying a moratorium to the Gulf Striped Bass fishery increased survival rates from 50% to 74% and resulted in the largest population growth of the individual management alternatives. These results could be used by the Committee to inform management decisions for other populations of Striped Bass in the Gulf Region.

Cooperator Science Series↗
USGS2011

Front matter: Preface, acknowledgements, table of contents

This volume is the fifth in a series of reports by the U.S. Geological Survey (USGS) on the assessment of the quantity and quality of the nation’s coal deposits that potentially could be mined during the next few decades. For eight years (1995-2003), geologic, geochemical, and resource information was collected and compiled for the five major coal-producing regions of the United States: the Appalachian Basin, Illinois Basin, Northern Rocky Mountains and Great Plains, Colorado Plateau, and the western part of the Gulf of Mexico Coastal Plain (Gulf Coast) region. The results of these other USGS coal assessments may be found at: http://energy.cr.usgs.gov/coal/coal_assessments/ index.html and a summary of the results from all assessment areas can be found in Ruppert et al. (2002) and Dennen (2009). This volume contains the assessment results for the Gulf Coast region. The contents of this volume were compiled mainly during the eight-year period mentioned above. However, every effort has been made to update the references and text to incorporate new work that has been completed since the original compilation period.

AAPG Studies in Geology↗
USGS2017

Variation and plasticity and their interaction with urbanization in Guadalupe Bass populations on and off the Edwards Plateau

The Colorado River Basin in Texas has experienced major alterations to its hydrologic regime due to changing land and water use patterns. These anthropogenic influences on hydrologic variability have had major implications for riparian and aquatic ecosystems and the species dependent upon them. However, impacts are often assessed at a limited temporal and spatial scale, tending to focus on relatively short and discrete periods or portions of a river basin. It is not clear how basin-wide alterations occurring over decades affect species. Guadalupe Bass Micropterus treculii are endemic to central Texas and are typically associated with shallow runs and riffles in small streams. However, Guadalupe Bass are found throughout the Colorado River Basin, including the mainstem portion of the lower river downstream of the city of Austin where they support a popular fishery. Because Guadalupe Bass exist across a wide range of stream orders within the basin, it is unclear whether populations respond similarly to anthropogenic disturbances or to conservation and restoration activities. Therefore, our objectives were to: Assess the effects of urbanization and hydrology on the population structure and dynamics of Guadalupe Bass. Evaluate the effects of environmental gradients on ecomorphological variation in Guadalupe Bass populations across multiple spatial scales. Describe the life history, habitat use, and behavior of the Guadalupe Bass population in the lower Colorado River and compare it to populations in more “typical” habitats. Results contribute to an understanding of the response of Guadalupe Bass to anthropogenic disturbances, including increased urbanization in central Texas and further assist in the conservation of the species. The ability of the population to not only persist, but flourish downstream of a heavily populated urban area presented a unique opportunity to investigate a native species response to anthropogenic disturbance. This research revealed differences in Guadalupe Bass habitat associations and movements, contrasts in age and growth, and morphological variation across a gradient of disturbance throughout the Colorado River Basin. Results of this work provide information on the potential effects of human population growth and increased water withdrawals on Guadalupe Bass populations. Additionally, this work adds to an understanding of the unique Guadalupe Bass population found in the lower Colorado River and how it differs from upstream tributary populations. Gathering additional population-level information facilitates conservation actions critical to preserving preferred habitat and promoting growth rates for Guadalupe Bass in streams of different sizes and flow conditions while highlighting interpopulation differences that may warrant consideration for stocking programs and other management strategies. Key findings of this study were: The similarity in response of growth rates to streamflow throughout the Colorado Basin suggests phenotypic plasticity in this trait rather than population-specific adaptations. Reductions in streamflows in the Colorado River Basin, whether due to increased frequency of drought or increased anthropogenic water withdrawal, will likely result in lower Guadalupe Bass growth rates with the potential to impact the structure of populations. Growth and recruitment showed a positive correlation with increased baseflows and mean monthly flows; however, continued assessment is necessary to determine a true relationship. We documented morphological divergence among Guadalupe Bass populations in response to spatial and temporal environmental variation. These ecomorphological differences among populations provide insight into the ability of Guadalupe Bass to respond to the differing in-stream habitat and flow conditions between small ‘typical’ tributary systems and the mainstem Colorado River. Morphological variation may be a population-level adaptation that potentially needs to be taken into consideration when choosing broodstock to maximize stocking success within a system. Understanding the morphological differences between Guadalupe Bass populations in response to local conditions could improve the success of restoration and supplemental stocking programs, especially in the ever-changing landscape of central Texas. We established a baseline for understanding the morphological response of Guadalupe Bass to increased population growth and the threats posed by increased water withdrawals and impervious surface. The mainstem population of Guadalupe Bass was generally more mobile, and more responsive to changes in streamflow, than tributary populations. The observed differences could influence the response of Guadalupe Bass populations to conservation and management actions, such as habitat restoration efforts. Continued monitoring of recruitment and angler exploitation may be beneficial to identify any changes that could negatively impact the population. Conservation initiatives solely focused on physical instream or riparian habitat are unlikely to be as beneficial to Guadalupe Bass as those focused on restoring or maintaining adequate streamflow

Cooperator Science Series↗