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

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At least 253 records · Page 14Linked to original sources
USGS2007

Walleye consumption and long-term population trends following gizzard shad introduction into a Western South Dakota reservoir

The gizzard shad ( Dorosoma cepedianum ) was introduced into 1,955-ha Angostura Reservoir, South Dakota to provide increased prey resources for walleye ( Sander vitreus ). Linear correlation analysis indicated that following gizzard shad introduction, walleye catch-per-unit-effort and mean length at age have increased over time (r = 0.68 to 0.85, P = 0.02 to 0.001). Walleye stomach contents were collected monthly from April through September, 2004 to determine the extent to which age-0 gizzard shad were being utilized as prey during the growing season. Age-0 gizzard shad were absent from walleye diets from April to mid-July (pre-shad-available period); however, from mid-July through early September (shad-available period), age-0 gizzard shad were an important prey item in all walleye diets. Mean weight decreased for walleyes of ages 2-5 during the spring, before age-0 gizzard shad became available; however, growth rate of walleyes increased appreciably during the shad-available period and was attributable to consumption of age-0 shad prey. In Angostura Reservoir, which lies at the northwestern edge of the gizzard shad range, walleye population characteristics have improved following shad introduction and during 2004, age-0 shad directly affected walleye feeding and growth.

South Dakota↗
USGS2011

Competitive interactions between walleye (Sander vitreus) and smallmouth bass (Micropterus dolomieu) under various controlled conditions

The range of smallmouth bass (Micropterus dolomieu) is expanding northward, creating new interactions with native predators, including walleye (Sander vitreus). We used a series of experiments to investigate competition between walleye (WAE) and smallmouth bass (SMB) at different life stages and light conditions, identified behaviors that allowed one fish to outcompete another, and evaluated whether prey switching mitigated competitive interactions. Juvenile and adult SMB appeared to outcompete WAE when fed during the daytime; neither species dominated when fed near dusk. Attack rates and capture efficiencies of both species were similar with an intra- or interspecific competitor, but SMB often exploited prey before the competitor had a chance to feed (exploitative competition) or displayed agonistic behaviors toward a potential competitor (interference competition). Prey selectivity of WAE or SMB did not differ when by themselves or with a potential competitor. These results indicate that SMB could outcompete WAE under limiting prey conditions due to the aggressive nature of SMB, but resources may be partitioned at least along a temporal scale. ?? 2011 Taylor & Francis.

Journal of Freshwater Ecology↗
USGS2013

Larval gizzard shad characteristics in Lake Oahe, South Dakota: A species at the northern edge of its range

Gizzard shad, Dorosoma cepedianum, have generally been restricted to the lower Missouri River impoundments in South Dakota. In recent years, gizzard shad numbers have increased in Lake Oahe, marking the northern-most natural population. These increases could potentially affect recreational fishes. Specifically, questions arise about larval gizzard shad growth dynamics and if age-0 gizzard shad in Lake Oahe will exhibit fast or slow growth, both of which can have profound effects on piscivore populations in this reservoir. In this study, we evaluated larval gizzard shad hatch timing, growth, and density in Lake Oahe. We collected larval gizzard shad from six sites from May to July 2008 and used sagittal otoliths to estimate the growth and back-calculate the hatch date. We found that larval gizzard shad hatched earlier in the upper part of the reservoir compared to the lower portion and that hatch date appeared to correspond to warming water temperatures. The peak larval gizzard shad density ranged from 0.6 to 33.6 (#/100 m 3 ) and varied significantly among reservoir sites. Larval gizzard shad growth ranged from 0.24 to 0.57 (mm/d) and differed spatially within the reservoir. We found no relationship between the larval gizzard shad growth or density and small- or large-bodied zooplankton density ( p  > 0.05). As this population exhibits slow growth and low densities, gizzard shad should remain a suitable forage option for recreational fishes in Lake Oahe.

South Dakota↗
USGS2023

Role of trace metal co-limitation in cyanobacterial blooms of Maumee Bay (Lake Erie) and Green Bay (Lake Michigan)

The open waters of large lakes can sometimes become so depleted in important metals that phytoplankton communities become either growth limited or limited in some metabolic function. Metals such as Fe, Ni, Mo, and Zn are used as co-factors for enzymes by phytoplankton in core metabolic functions, as well as metabolic pathways that allow phytoplankton to use less preferred forms of N and P (e.g. nitrates, urea, and organic phosphorus). In the Laurentian Great Lakes, metal limitation has been observed primarily in waters that are isolated from tributary inputs and sediment exchange. These are situations where the supply of metals is very low relative to demand. We hypothesized that another situation where metal limitation could occur is within algal blooms, where the demand for metals is high because preferred forms of N and P are often low or absent and the phytoplankton biomass is extremely high. As a preliminary test of this hypothesis, we performed seven laboratory incubation experiments on naturally occurring phytoplankton communities from two nearshore habitats that frequently experience blooms (Green Bay in Lake Michigan and Maumee Bay in Lake Erie). Metals and labile nutrients (inorganic N and P) were often present at low concentrations or below the method detection limit. Amendments of inorganic N (5 experiments) and P (1 one experiment) resulted in increased chlorophyll in laboratory incubations, but metal amendments alone never appeared to stimulate growth. Although we attempted to sample during conditions when we hypothesized metal limitation would be most likely, we cannot rule out the possibility that metal limitation is occurring at other times in these eutrophic nearshore areas. Further, metal availability could affect other aspects of the phytoplankton community, such as the production of cyanotoxins or the interactions between different phytoplankton taxa.

Michigan, Ohio, Wisconsin↗
USGS2023

Characterization of fish assemblages in eleven multi-use reservoirs from North Carolina, USA

Managing impounded river systems is a recurring challenge for aquatic resource professionals because reservoirs serve multiple functions with different ecological and socioeconomic outcomes. However, research on fishes in reservoirs has disproportionally focused on recreationally and economically important species, with less attention directed toward fish assemblages despite the potential for management at the assemblage level. As such, evaluation of relationships between reservoir fish assemblages and biotic and abiotic factors and testing whether assemblage structure is affected by changing environmental conditions may deepen ecological understanding and provide insights for reservoir fisheries management. Our overall objective was to assess these relationships in 11 reservoirs from North Carolina, USA. We sampled fish assemblages in the reservoirs, which spanned five river basins representing a range of habitat conditions, using experimental gillnets and pulsed DC nighttime electrofishing. Multivariate statistical analyses indicated that taxonomic differences in fish assemblage composition among river basins followed a gradient of productivity. The top contributing species to reservoir dissimilarity were bluegill ( Lepomis macrochirus ), gizzard shad ( Dorosoma cepedianum ), black crappie ( Pomoxis nigromaculatus ), and white perch ( Morone americana ). These four species were positively associated with factors that reflect increasing eutrophic conditions in the 11 reservoirs and could, therefore, serve as indicators of reservoir productivity, anthropogenic influence, and fish assemblage structure, in addition to their key role in reservoir fisheries management. Whereas ­fisheries research has historically focused on assessing fish ­populations, our results illustrate the ecological and management insights derived from simultaneously collecting assemblage- and population-level data. Research on reservoir fish assemblages in relation to biotic and abiotic conditions may help advance fish ecology and management alike.

North Carolina↗
USGS2011

Passive immunization of Pacific herring against viral hemorrhagic septicemia.

The plasma of Pacific herring Clupea pallasii that survived laboratory-induced viral hemorrhagic septicemia (VHS) epizootics contained humoral substances that, when injected into naive animals, conferred passive immunity against the disease. Among groups exposed to viral hemorrhagic septicemia virus (VHSV), injection of donor plasma from VHS survivors resulted in significantly greater survival (50%) and significantly lower tissue titers (1.5 x 10(5) plaque-forming units [PFU]/g) than the injection of plasma from VHSV-naive donors (6% survival; 3.7 x 10(6) PFU/g). Additionally, the magnitude of the protective immune response increased during the postexposure period; plasma that was collected from survivors at 123 d postexposure (931 degree-days) provided greater protection than plasma collected from survivors at 60 d postexposure (409 degree-days). These results provide proof of concept that the VHSV exposure history of Pacific herring populations can be determined post hoc; furthermore, the results can be used as the foundation for developing additional high-throughput diagnostic techniques that may be effective at quantifying herd immunity and forecasting the potential for future VHS epizootics in populations of wild Pacific herring.

Journal of Aquatic Animal Health↗
USGS2013

Ammocoetes of Pacific lamprey are not susceptible to common fish rhabdoviruses of the U.S. Pacific Northwest

Pacific Lampreys Entosphenus tridentatus have experienced severe population declines in recent years and efforts to develop captive rearing programs are under consideration. However, there is limited knowledge of their life history, ecology, and potential to harbor or transmit pathogens that may cause infectious disease. As a measure of the possible risks associated with introducing wild lampreys into existing fish culture facilities, larval lampreys (ammocoetes) were tested for susceptibility to infection and mortality caused by experimental exposures to the fish rhabdovirus pathogens: infectious hematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV). Two IHNV isolates, representing the U and M genogroups, and one VHSV isolate from the IVa genotype were each delivered to groups of ammocoetes by immersion at moderate and high viral doses, and by intraperitoneal injection. Ammocoetes were then held in triplicate tanks with no substrate or sediment. During 41 d of observation postchallenge there was low or no mortality in all groups, and no virus was detected in the small number of fish that died. Ammocoetes sampled for incidence of infection at 6 and 12 d after immersion challenges also had no detectable virus, and no virus was detected in surviving fish from any group. A small number of ammocoetes sampled 6 d after the injection challenge had detectable virus, but at levels below the original quantity of virus injected. Overall there was no evidence of infection, replication, or persistence of any of the viruses in any of the treatment groups. Our results suggest that Pacific Lampreys are highly unlikely to serve as hosts that maintain or transmit these viruses.

Journal of Aquatic Animal Health↗
USGS2016

Dermocystidium sp. infection in Blue Ridge Sculpin captured in Maryland

Raised pale cysts were observed on Blue Ridge Sculpin Cottus caeruleomentum during stream fish community surveys in Catoctin Mountain Park, Maryland. When examined histologically, preserved sculpin exhibited multiple cysts containing spherical endospores with a refractile central body characteristic of Dermocystidium spp. Cysts were not observed on the gills or internally. The portion of the watershed in which affected sculpin were observed contained lower than expected numbers of sculpin, raising concerns about the population effects of this infection. A nearby stream lacked sculpin even though they are common in this region, further suggesting the possibility of regional effects. This is the first report of a Dermocystidium infecting any fish species in the eastern United States.

Maryland↗
USGS2017

In memoriam - William Toshio (Tosh) Yasutake, 1922-2016

William Toshio (Tosh) Yasutake, 1922-2016 passed away peacefully at home on December 12, 2016, at the age of 94. He is survived by Fumi, his wife of 66 years, as well as four children and six grandchildren. With his death, the fish health community has lost an outstanding scientist as well as a kind, unassuming, and wonderful human being. Tosh was born on June 10, 1922, in Seattle, Washington, to Jack and Hide Yasutake. He was in his first year of studies at the University of Washington when Pearl Harbor was attacked by Imperial Japan on December 7, 1941. Following the attack, Tosh and his family (father, mother, sister, and two brothers) were among the 110,000–120,000 people of Japanese ancestry who were forced from their homes on the Pacific coast and incarcerated in internment camps in the interior. In June 1942, Tosh enlisted in the U.S. Army, serving as an unarmed combat medic in the famed 442nd Regimental Combat Team, the most decorated unit for its size and length of service in the history of American warfare. Wounded in October 1944 during the Vosges Mountains campaign near Bruyères, France, Tosh was evacuated and missed the ensuing battle to rescue the “Lost Battalion,” at which his replacement was killed. Tosh returned to action in Italy in February 1945 and served until the end of the war in Europe, earning both a Purple Heart and a Bronze Star for bravery. In October 2010, the Congressional Gold Medal was awarded to the 442nd Regimental Combat Team, and in 2012 the surviving members were made chevaliers of the French Légion d’Honneur for actions contributing to the liberation of France in World War II. After the war, Tosh returned to the University of Washington on the GI Bill and received a B.S. degree in zoology in 1951. In 1953 he began his research career at the U.S. Fish and Wildlife Service’s Western Fish Nutrition Laboratory at Cook, Washington, where he conducted pioneering research on nutritional fish diseases with John Halver. Tosh was one of the first to recognize hepatomas in hatchery-reared Rainbow Trout and helped to trace the disease to an aflatoxin produced by the mold Aspergillus flavis , which grew during the storage of ingredients for fish diets. In 1960, he transferred to the Western Fisheries Research Center (WFRC) in Seattle (then called the Western Fish Disease Laboratory) to start a fish pathology diagnostic laboratory. There he described the histopathology of diseases of economically important fishes, identified etiologic agents, and worked with hatchery biologists to improve the health, quality, and survival of salmonids released from federal and state hatcheries. Tosh was instrumental in recognizing that the viruses of Oregon sockeye disease and Chinook Salmon virus disease were one entity and in giving the disease its present name: infectious hematopoietic necrosis. In recognition of his pioneering research, Tosh was awarded a doctorate in fish pathology by the University of Tokyo in 1980, the first American to have been so honored. In 1983, he published his classic textbook The Microscopic Anatomy of Salmonids: An Atlas , which quickly became a standard reference work in fish pathology and is still in wide use today. For his outstanding career achievements, in 1987 Tosh received the S. F. Snieszko Distinguished Service Award, the highest honor bestowed by the American Fisheries Society’s Fish Health Section (AFS–FHS). Tosh retired in 1988 but continued his research at the WFRC as a senior scientist emeritus, providing technical assistance to federal and state agencies and to the aquaculture industry worldwide. His culminating project was to digitize his lifetime collection of photomicrographs and prepare an atlas, “Histopathology of Selected Parasitic Salmonid Diseases: A Color Atlas,” that is now posted on the Web sites of the WFRC and the AFS–FHS. Although his presence will be sorely missed, his research contributions have become part of the foundation of today’s knowledge of fisheries biology and have assured him a place in history.

Journal of Aquatic Animal Health↗
USGS2011

Evaluating impacts of subdivision density on shallow groundwater in Southeastern Wisconsin, USA

Using simple numerical groundwater flow models, we tested the impacts of suburban developments on groundwater levels and discharge to streams. We used lot sizes of 1, 3 and 5 acres (4000, 12,000 and 20,000 m 2 ) with one domestic well per lot that pumped water from shallow aquifers. Our modelling showed that pumping had little impact on water levels and groundwater discharge to streams if the developed area is of a moderate size. However, domestic wells had the potential to impact local groundwater levels and baseflows in large developments. In township-wide development scenarios of 1-acre (4000 m 2 ) lots, simulated drawdowns beneath developed areas ranged from 1 to 18 ft (0.3 to 5.5 m), and baseflow reductions ranged from 20 to 40%. Impacts generally were inversely proportional to lot size, recharge rate and hydraulic conductivity of the aquifer materials. Developments using individual domestic wells have the potential to impact local groundwater levels and surface water features. The impacts can range from negligible to severe, depending on local hydrogeologic conditions and on whether wastewater is recharged onsite or is removed from the basin. An assessment of groundwater impacts should be a part of the planning process for all suburban developments.

Wisconsin↗
USGS2009

Mercury and drought along the Lower Carson River, Nevada: III. effects on blood and organ biochemistry and histopathology of snowy egrets and black-crowned night-herons on Lahontan Reservoir, 2002-2006

A 10-year study (1997-2006) was conducted to evaluate reproduction and health of aquatic birds in the Carson River Basin of northwestern Nevada (on the U.S. Environmental Protection Agency Natural Priorities List) due to high mercury (Hg) concentrations from past mining activities. This part of the study evaluated physiological associations with blood Hg in young snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax), and organ biochemistry and histopathological effects in snowy egrets on Lahontan Reservoir (LR) from the period 2002-2006. LR snowy egret geometric mean total Hg concentrations (μg/g ww) ranged from 1.5 to 4.8 for blood, 2.4 to 3.1 liver, 1.8 to 2.5 kidneys, 1.7 to 2.4 brain, and 20.5 to 36.4 feathers over these years. For night-herons, mean Hg for blood ranged from 1.6 to 7.4. Significant positive correlations were found between total Hg in blood and five plasma enzyme activities of snowy egrets suggesting hepatic stress. Histopathological findings revealed vacuolar changes in hepatocytes in LR snowy egrets as well as correlation of increased liver inflammation with increasing blood and tissue Hg. Hepatic oxidative effects were manifested by decreased hepatic total thiol concentration and glutathione reductase activity and elevated hepatic thiobarbituric acid-reactive substances (TBARS), a measure of lipid peroxidation. However, other hepatic changes indicated compensatory mechanisms in response to oxidative stress, including decreased oxidized glutathione (GSSG) concentration and decreased ratio of GSSG to reduced glutathione. In young black-crowned night-herons, fewer correlations were apparent. In both species, positive correlations between blood total Hg and plasma uric acid and inorganic phosphorus were suggestive of renal stress, which was supported by histopathological findings. Both oxidative effects and adaptive responses to oxidative stress were apparent in kidneys and brain. Vacuolar change and inflammation in peripheral nerves were found to correlate with blood and tissue Hg. Hg-associated effects related to the immune system included alterations in specific white blood cells and lymphoid depletion in the bursa that were correlated with blood and tissue Hg. When the number of plasma variables that differed between young snowy egrets from the LR site and the reference site were compared between wet and drought years, over twice as many variables were affected during drought years. This resulted in many more variables correlating with blood total Hg during dry than during wet years, suggesting the combination of drought and Hg was more stressful than Hg alone. Drought may have exacerbated Hg-related effects as reported previously for overall productivity. This relationship was not evident in black-crowned night-herons, although data were more limited.

Nevada↗
USGS2010

Evidence of weak contaminant-related oxidative stress in glaucous gulls (Larus hyperboreus) from the Canadian arctic

Environmental contaminants are transported over great distances to Arctic ecosystems, where they can accumulate in wildlife. Whether contaminant concentrations in wildlife are sufficient to produce adverse effects remains poorly understood. Exposure to contaminants elevates oxidative stress with possible fitness consequences. The glaucous gull ( Larus hyperboreus ), an Arctic top predator, was used as a bioindicator for investigating relationships between contaminant levels (organochlorines and polychlorinated biphenyls [OC/PCB], mercury [Hg], and selenium [Se]) and measures of oxidative stress (glutathione [GSH] metabolism and lipid peroxidation) in Canadian Arctic ecosystems. Contaminant levels were low and associations between contaminant exposure and oxidative stress were weak. Nevertheless, glutathione peroxidase activity rose with increasing hepatic Se concentrations, levels of thiols declined as Hg and OC/PCB levels rose, and at one of the two study sites levels of lipid peroxidation were elevated with increasing levels of hepatic Hg. These results suggest the possibility of a deleterious effect of exposure to contaminants on gull physiology even at low contaminant exposures.

Arctic↗
USGS2013

From the Island of the Blue Dolphins : A unique 19th century cache feature from San Nicolas Island, California

A cache feature salvaged from an eroding sea cliff on San Nicolas Island produced two redwood boxes containing more than 200 artifacts of Nicoleño, Native Alaskan, and Euro-American origin. Outside the boxes were four asphaltum-coated baskets, abalone shells, a sandstone dish, and a hafted stone knife. The boxes, made from split redwood planks, contained a variety of artifacts and numerous unmodified bones and teeth from marine mammals, fish, birds, and large land mammals. Nicoleño-style artifacts include 11 knives with redwood handles and stone blades, stone projectile points, steatite ornaments and effigies, a carved stone pipe, abraders and burnishing stones, bird bone whistles, bone and shell pendants, abalone shell dishes, and two unusual barbed shell fishhooks. Artifacts of Native Alaskan style include four bone toggling harpoons, two unilaterally barbed bone harpoon heads, bone harpoon fore-shafts, a ground slate blade, and an adze blade. Objects of Euro-American origin or materials include a brass button, metal harpoon blades, and ten flaked glass bifaces. The contents of the cache feature, dating to the early-to-mid nineteenth century, provide an extraordinary window on a time of European expansion and global economic development that created unique cultural interactions and social transformations.

California↗
USGS2026

Statewide surficial geologic map of Nebraska underscores Quaternary landscape evolution from the High Plains to the Central Lowland

Surficial geologic mapping in Nebraska has been conducted primarily at the 1:24,000 scale since the mid-1990s, although there have also been limited efforts to map generalized Quaternary and surficial geology within the state and the region. We compiled and evaluated disparate maps (1:24,000–1:1,000,000) and datasets—including geologic, soil and soil parent material, and geomorphic maps as well as LiDAR derivatives—to produce a single 1:500,000 scale surficial geologic map of Nebraska that is the first of its kind. This new map provides a coarse-scale surficial geologic map that will be incorporated into a nationwide U.S. Geological Survey Quaternary geologic map. It also reflects the variation and uniqueness of physical landscapes in the state, where the Great Plains and Central Lowland physiographic provinces meet, further developing a richer interdisciplinary understanding of regional geomorphology in the heart of North America.

Nebraska↗
USGS2007

The FORE-SCE model: a practical approach for projecting land cover change using scenario-based modeling

A wide variety of ecological applications require spatially explicit, historic, current, and projected land use and land cover data. The U.S. Land Cover Trends project is analyzing contemporary (1973–2000) land-cover change in the conterminous United States. The newly developed FORE-SCE model used Land Cover Trends data and theoretical, statistical, and deterministic modeling techniques to project future land cover change through 2020 for multiple plausible scenarios. Projected proportions of future land use were initially developed, and then sited on the lands with the highest potential for supporting that land use and land cover using a statistically based stochastic allocation procedure. Three scenarios of 2020 land cover were mapped for the western Great Plains in the US. The model provided realistic, high-resolution, scenario-based land-cover products suitable for multiple applications, including studies of climate and weather variability, carbon dynamics, and regional hydrology.

Journal of Land Use Science↗
USGS2013

Projected surface radiative forcing due to 2000--2050 land-cover land-use albedo change over the eastern United States

Satellite-derived contemporary land-cover land-use (LCLU) and albedo data and modeled future LCLU are used to study the impact of LCLU change from 2000 to 2050 on surface albedo and radiative forcing for 19 ecoregions in the eastern United States. The modeled 2000–2050 LCLU changes indicate a future decrease in both agriculture and forested land and an increase in developed land that induces ecoregion radiative forcings ranging from −0.175 to 0.432 W m −2 driven predominately by differences in the area and type of LCLU change. At the regional scale, these projected LCLU changes induce a net negative albedo decrease (−0.001) and a regional positive radiative forcing of 0.112 W m −2 . This overall positive forcing (i.e., warming) is almost 4 times greater than that estimated for documented 1973–2000 LCLU albedo change published in a previous study using the same methods.

Journal of Land Change Science↗
USGS2017

Human drivers, biophysical changes, and climatic variation affecting contemporary cropping proportions in the northern prairie of the U.S

Grassland to cropland conversion in the northern prairie of the United States has been a topic of recent land use change studies. Within this region more corn and soybeans are grown now (2017) than in the past, but most studies to date have not examined multi-decadal trends and the synergistic web of socio-ecological driving forces involved, opting instead for short-term analyses and easily targeted agents of change. This paper examines the coalescing of biophysical and socioeconomic driving forces that have brought change to the agricultural landscape of this region between 1980 and 2013. While land conversion has occurred, most of the region’s cropland in 2013 had been previously cropped by the early 1980s. Furthermore, the agricultural conditions in which crops were grown during those three decades have changed considerably because of non-biophysical alterations to production practices and changing agricultural markets. Findings revealed that human drivers played more of a role in crop change than biophysical changes, that blending quantitative and qualitative methods to tell a more complete story of crop change in this region was difficult because of the synergistic characteristics of the drivers involved, and that more research is needed to understand how farmers make crop choice decisions.

Minnesota, North Dakota, South Dakota↗
USGS2018

Urban growth and landscape connectivity threats assessment at Saguaro National Park, Arizona, USA

Urban and exurban expansion results in habitat and biodiversity loss globally. We hypothesize that a coupled-model approach could connect urban planning for future cities with landscape ecology to consider wildland habitat connectivity. Our work combines urban growth simulations with models of wildlife corridors to examine how species will be impacted by development to test this hypothesis. We leverage a land use change model (SLEUTH) with structural and functional landscape-connectivity modeling techniques to ascertain the spatial extent and locations of connectivity related threats to a national park in southern Arizona, USA, and describe how protected areas might be impacted by urban expansion. Results of projected growth significantly altered structural connectivity (80%) when compared to current (baseline) corridor conditions. Moreover, projected growth impacted functional connectivity differently amongst species, indicating resilience of some species and near-complete displacement of others. We propose that implementing a geospatial-design-based model will allow for a better understanding of the impacts management decisions have on wildlife populations. The application provides the potential to understand both human and environmental impacts of land-system dynamics, critical for long-term sustainability.

Arizona↗