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At least 865 records · Page 48Linked to original sources

USGS2019

Growth, condition, and trophic relations of stocked trout in southern Appalachian mountain streams

Stream trout fisheries are among the most popular and valuable in the United States, but many are dependent on hatcheries to sustain fishing and harvest. Thus, understanding the ecology of hatchery‐reared trout stocked in natural environments is fundamental to management. We evaluated the growth, condition, and trophic relations of Brook Trout Salvelinus fontinalis , Brown Trout Salmo trutta , and Rainbow Trout Oncorhynchus mykiss that were stocked in southern Appalachian Mountain streams in western North Carolina. Stocked and wild (naturalized) trout were sampled over time (monthly; September 2012–June 2013) to compare condition and diet composition and to evaluate temporal dynamics of trophic position with stable isotope analysis. Relative weights ( W r ) of stocked trout were inversely associated with their stream residence time but were consistently higher than those of wild trout. Weight loss of harvested stocked trout was similar among species and sizes, but fish stocked earlier lost more weight. Overall, 40% of 141 stomachs from stocked trout were empty compared to 15% of wild trout stomachs ( N = 26). We identified a much higher rate of piscivory in wild trout (18 times that of stocked trout), and wild trout were 4.3 times more likely to consume gastropods relative to stocked trout. Hatchery‐reared trout were isotopically similar to co‐occurring wild fish for both δ 13 C and δ 15 N values but were less variable than wild trout. Differences in sulfur isotope ratios (δ 34 S) between wild and hatchery‐reared trout indicated that the diets of wild fish were enriched in δ 34 S relative to the diets of hatchery‐reared fish. Although hatchery‐reared trout consumed prey items similar to those of wild fish, differences in consumption or behavior (e.g., reduced feeding) may have resulted in lower condition and negative growth. These findings provide critical insight on the trophic dynamics of stocked trout and may assist in developing and enhancing stream trout fisheries.

North Carolina↗

USGS2021

Movement dynamics and survival of stocked Colorado River Cutthroat Trout

The ability of native fish to establish self-sustaining populations when reintroduced to vacant habitats is variable. We evaluated factors that potentially affect the reintroduction success of juvenile Colorado River Cutthroat Trout Oncorhynchus clarkii pleuriticus that were reintroduced to an isolated watershed and were experiencing suboptimal survival and recruitment. We conducted a 3-year mark–recapture study to model annual apparent survival probability as it related to (1) different ex situ rearing strategies and (2) initial release among different habitat types. The use of PIT tags also enabled the quantification of loss via emigration. Apparent survival was highest for small fish that were minimally exposed to ex situ rearing conditions, stocked in small, headwater stream reaches. However, maximum estimates of apparent survival remained low (≤0.38 ± 0.05 [estimate ± SE]) regardless of rearing treatment, stocking location, or interactive effects between covariates. Emigration of stocked fish (<1%) from the study area did not appear to limit their establishment. Our results suggest that variation in stocking and rearing strategy may have some effect on translocation success and the interaction between rearing and stocking strategy highlights the importance of considering the life history stage of stocked individuals when identifying stocking sites. Consistently low annual survival values may be indicative of a larger issue, requiring in-depth evaluation of adaptive potential within our brood source and other factors that potentially limit population persistence.

Wyoming↗

USGS2022

Attraction, entrance, and passage efficiency of Arctic Grayling, trout, and suckers at Denil fishways in the Big Hole River basin, Montana

The Big Hole River basin in southwestern Montana supports the only indigenous, self‐sustaining fluvial population of Arctic Grayling Thymallus arcticus in the conterminous United States, but the basin is fragmented by numerous low‐head irrigation diversion dams. Denil fishways at 63 diversion dams provide Arctic Grayling and other fishes opportunities for year‐round access to critical habitats; however, their efficiency has not been evaluated. We quantified attraction, entrance, and passage for hatchery‐reared Arctic Grayling, wild trout (Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta ), and wild suckers (White Sucker Catostomus commersonii and Longnose Sucker C. catostomus ) during 14 field trials conducted at six Denil fishways over a representative range of fishway slopes and hydraulic conditions using passive integrated transponder telemetry. Attraction (60.4–84.3%) and entrance (44.3–78.6%) efficiencies were variable across test conditions and reduced overall fishway efficiencies (19.1–55.8%). In contrast, upon entry, passage efficiencies were high (96.2–97.0%) for all taxa across all test conditions. Attraction of hatchery‐reared Arctic Grayling increased with upstream depth (a surrogate for fishway discharge) and attraction flow, but attraction of wild fish was less affected by these conditions. Entrance of Arctic Grayling, Brook Trout, and Brown Trout decreased with upstream depth and fishway slope, especially when plunging entrance conditions associated with shallow downstream depths were present. However, entrance of Arctic Grayling and both trout species increased with downstream depth, and submerged fishway entrances demonstrated promise for increasing entrance efficiency at fishways with high discharges and steep slopes. We demonstrate that comprehensive evaluations of fishway efficiency components can identify specific solutions that improve fishway efficiency; application of these engineering solutions at individual fishways (as needed) could improve their efficiency and further enhance aquatic connectivity for fishes in the Big Hole River basin and elsewhere.

Montana↗

USGS2023

Seasonal spatial ecology of Lake Trout in Lake Erie

Objective Lake Trout Salvelinus namaycush are native coldwater apex predators that play an important role in maintaining ecosystem functionality and diversity in the Laurentian Great Lakes. Following population collapses, rehabilitation efforts were widely initiated in the Great Lakes to reestablish self‐sustaining Lake Trout populations. Lake Erie may pose a challenge to these rehabilitation efforts due to limited availability of appropriate oxythermal habitat. Our goal was to investigate seasonal habitat use of adult Lake Trout in Lake Erie to inform management and rehabilitation efforts. Methods We used acoustic telemetry in Lake Erie, which was equipepd with a lake‐wide acoustic receiver grid, to quantify Lake Trout seasonal region occupancy, dispersal distances, bottom depth occupancy, space use extent, and space use overlap. Result We found that 32% of fish tagged in the eastern basin and all fish from the western basin dispersed more than 100 km from their tagging location, which represents a greater proportion of the population moving long distances than what has been previously documented in the Great Lakes. During stratification, Lake Trout were detected almost exclusively in the offshore eastern basin in areas where water depth exceeded 25 m. During nonstratified seasons, fish used other regions of the lake, occupying areas of highly variable depths. During fall, most fish tagged in the eastern basin occupied habitat along the southern shore of the eastern basin. Fish tagged in the western basin returned to this region in the fall of subsequent years despite occupying the offshore eastern basin during stratification and having depth occupancy, home range size, and overlap similar to that of eastern basin‐tagged fish. Fish size was positively correlated with receiver depth during winter and spring, and with home range overlap during spring and summer. Conclusion The results of this study can begin to inform management decisions regarding stocking locations, harvest regulations, and habitat restoration to facilitate the continued rehabilitation of this important native species.

Lake Erie↗

USGS2021

The application of metacommunity theory to the management of riverine ecosystems

River managers strive to use the best available science to sustain biodiversity and ecosystem function. To achieve this goal requires consideration of processes at different scales. Metacommunity theory describes how multiple species from different communities potentially interact with local-scale environmental drivers to influence population dynamics and community structure. However, this body of knowledge has only rarely been used to inform management practices for river ecosystems. In this article, we present a conceptual model outlining how the metacommunity processes of local niche sorting and dispersal can influence the outcomes of management interventions and provide a series of specific recommendations for applying these ideas as well as research needs. In all cases, we identify situations where traditional approaches to riverine management could be enhanced by incorporating an understanding of metacommunity dynamics. A common theme is developing guidelines for assessing the metacommunity context of a site or region, evaluating how that context may affect the desired outcome, and incorporating that understanding into the planning process and methods used. To maximize the effectiveness of management activities, scientists, and resource managers should update the toolbox of approaches to riverine management to reflect theoretical advances in metacommunity ecology.

WIREs Water↗

USGS2022

Applied citizen science in freshwater research

Worldwide, scientists are increasingly collaborating with the general public. Citizen science methods are readily applicable to freshwater research, monitoring, and education. In addition to providing cost-effective data on spatial and temporal scales that are otherwise unattainable, citizen science provides unique opportunities for engagement with local communities and stakeholders in resource management and decision-making. However, these methods are not infallible. Citizen science projects require deliberate planning in order to collect high data quality and sustain meaningful community partnerships. Citizen science practitioners also have an ethical responsibility to ensure that projects are not putting the safety of participants at stake. We discuss here how citizen science is being applied in freshwater research, emerging challenges in project planning and implementation, as well as how citizen science is shaping public understanding, policy, and management of freshwaters.

WIREs Water↗

USGS2024

Food for fish: Challenges and opportunities for quantifying foodscapes in river networks

Riverine fishes face many challenges including habitat degradation and climate change, which alter the productivity of the riverscapes in which fish live, reproduce, and feed. Understanding the watershed portfolio of foraging and growth opportunities that sustain productive and resilient fish populations is important for prioritizing conservation and restoration. However, the spatiotemporal distribution and availability of fish food are poorly understood relative to other factors such as abiotic habitat quantity and quality (e.g., water temperature). In this paper, we build on the concept of “foodscapes,” and describe three components of food for fish, including abundance, accessibility, and quality. We then discuss methodological advances to help address three key questions: (1) Why is food availability hard to estimate? (2) What are the consequences of uncertainty in food availability estimates? and (3) What approaches are available or emerging for quantifying food available to fish? To address the first question, we characterize data acquisition and analytical challenges; for the second, we demonstrate the importance of evaluating and communicating potential consequences of uncertainty; and for the third, we posit opportunities for future work. Collectively, we highlight the need for greater appreciation of the role food plays in stream fish conservation, especially given its critical influence on responses to warming temperatures.

WIREs Water↗

USGS2012

Raptor community composition in the Texas Southern High Plains lesser prairie-chicken range

Predation can be a factor in preventing prey population growth and sustainability when prey populations are small and fragmented, and when predator density is unrelated to the density of the single prey species. We conducted monthly raptor surveys from February 2007 to May 2009 in adjacent areas of the Texas Southern High Plains (USA) that do and do not support lesser prairie-chickens ( Tympanuchus pallidicinctus ), a candidate for protection under the Endangered Species Act. During the summer period corresponding to prairie-chicken nesting and brood-rearing, Swainson's hawks ( Buteo swainsoni ) were the most abundant raptor. During the lekking and overwintering period, the raptor community was diverse, with northern harriers ( Circus cyaneus ) being the most abundant species. Raptor abundance peaked during the early autumn and was lowest during the spring. Utility poles were a significant predictor of raptor density at survey points and Swainson's hawks and all raptors, pooled, were found in greater densities in non-prairie-chicken habitat dominated by mesquite ( Prosopis glandulosa ). Avian predation risk on prairie-chickens, based on presence and abundance of raptors, appears to be greatest during winter when there is a more abundant and diverse raptor community, and in areas with utility poles.

Wildlife Society Bulletin↗

USGS2025

Informing adaptive management to reduce ungulate aggregations: A case study involving winter feeding of elk

In the United States, wildlife managers are entrusted with preserving culturally and economically important ungulate populations in the face of the ongoing spread of chronic wasting disease (CWD). The U.S. Fish and Wildlife Service established an adaptive management plan to reduce the reliance of elk ( Cervus canadensis ) on supplemental winter feeding on the National Elk Refuge. The end goal of reducing the unnaturally high aggregation of elk during the winter is to mitigate the threat of disease outbreaks and to meet the objectives of sustainable populations of elk on the refuge. In this case study, we evaluated 6 years (2017–2022) of data from GPS-collared elk to determine the efficacy of shortening the length of the annual feeding period on the refuge to reduce elk aggregation. We measured aggregation using proximity rates, based on pairwise interactions over time, in both raw form as an index as well as predicted proximity as a function of other abiotic influences. We created a new R package, wildagg , to help with the process of computing the metrics from our study and to increase reproducibility in the future. Aggregation declined in years with less feeding on the refuge according to raw aggregation metrics when examined in isolation and dependent on the baseline feeding year used for comparison. However, accounting for abiotic factors while modeling proximity rates suggested in some years the decision to shorten the feeding period had less influence on aggregation than predicted. Our results underscore the complexity of measuring management outcomes and the usefulness of multiple approaches to evaluation.

Wyoming↗

USGS2016

Canada goose nest survival at rural wetlands in north-central Iowa

The last comprehensive nest survival study of the breeding giant Canada goose ( Branta canadensis maxima ) population in Iowa, USA, was conducted >30 years ago during a period of population recovery, during which available nesting habitat consisted primarily of artificial nest structures. Currently, Iowa's resident goose population is stable and nests in a variety of habitats. We analyzed the effects of available habitat on nest survival and how nest survival rates compared with those of the expanding goose population studied previously to better understand how to maintain a sustainable Canada goose population in Iowa. We documented Canada goose nest survival at rural wetland sites in north-central Iowa. We monitored 121 nests in 2013 and 149 nests in 2014 at 5 Wildlife Management Areas (WMAs) with various nesting habitats, including islands, muskrat ( Ondatra zibethicus ) houses, and elevated nest structures. We estimated daily nest-survival rate using the nest survival model in Program MARK. Survival was influenced by year, site, stage, presence of a camera, nest age, and an interaction between nest age and stage. Nest success rates for the 28-day incubation period by site and year combination ranged from 0.10 to 0.84. Nest survival was greatest at sites with nest structures (β = 17.34). Nest survival was negatively affected by lowered water levels at Rice Lake WMA (2013 β = −0.77, nest age β = −0.07). Timing of water-level drawdowns for shallow lake restorations may influence nest survival rates.

Iowa↗

USGS2018

Evaluating airsoft electric guns for control of invasive brown treesnakes

Firearms are often used in lethal control of invasive vertebrates, but safety and regulatory aspects limit the circumstances under which they can be used. During August 2016 at the Brown Treesnake Project laboratory on Guam, we evaluated hobby‐grade Airsoft Electric Guns (AEGs)—a lower powered, less‐hazardous, and less‐regulated alternative to firearms—for capture and control of small animals, with specific emphasis on invasive brown treesnakes ( Boiga irregularis ). Tests of AEGs differing in power with ammunition (plastic pellets) masses ranging from 0.20 to 0.39 g, fired at gelatin blocks from distances of 4, 8, and 12 m, showed that heavy ammunition is of overriding importance for maximizing lethality: 0.39‐g pellets penetrated more deeply at 12 m than did 0.20‐g pellets at 4 m. Inspection of tissue damage in brown treesnake carcasses subjected to fire with the 0.39‐g ammunition from the same distances suggested that injuries sustained by a direct hit from 12 m would often be lethal, and snakes would be unlikely to survive multiple hits from automatic fire discharged at approximately 17/s. Limited trials with live snakes helped us to understand behavioral responses in a snake hit by ≥1 pellets, including distance traveled over time. Based on these factors, we assessed the risk that a snake injured by pellet fire might evade subsequent capture by rapid responders in the proximity. We also discuss ethical considerations and regulatory advantages of using AEGs. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Wildlife Society Bulletin↗

USGS2005

Crane reproductive physiology and conservation

Some unique features of crane reproduction, management, and conservation are described. Because cranes are sexually monomorphic, sexing is difficult and must be accomplished using behavior, laparoscopy, cloacal examination, genetic techniques, or fecal steroid analysis. Although husbandry techniques for cranes are similar to those used with other nondomestic birds, a number of basic characteristics, such as extreme aggressiveness, imprinting by the crane chick on man, a delayed molt in the immature crane, delayed sexual maturity, and infertility, pose special problems for the propagator. Artificial insemination is a practical solution to crane infertility. Vigorous captive management and propagation efforts must become increasingly important if several endangered crane species are to survive the continuing decline in wild populations. The ultimate goal is the restoration of suitable habitat and sustainable native populations.

Zoo Biology↗

USGS1995

Sediment resuspension mechanisms in Old Tampa Bay, Florida

The mechanisms that resuspend bottom sediments in Old Tampa Bay, a shallow, microtidal, subtropical estuary in west-central Florida, were determined by analysing data collected during several periods from 1988 to 1990. Hydrodynamic and suspended-solids concentration data were collected at a relatively deep (4 m) site where a permanent platform was built and at a relatively shallow (1·5 m) site where a submersible instrument package was deployed. Bottom sediments were non-cohesive silts and fine sands. The primary sediment resuspension mechanism at both sites was wind waves, which were generated by strong and sustained winds associated with winter storms and tropical storms. At the platform, waves were depth-transitional, and estimated bottom shear stresses were most sensitive to wave period and water depth. Concentrations of suspended solids at this site corresponded well with wave motion, and non-linear wave-current interaction was small. At the shallow-water site, concentrations of suspended solids were elevated during periods of strong north-easterly winds and large bottom orbital velocities. At both sites, wind direction was an important factor in determining the occurrence and magnitude of sediment resuspension. Resuspended sediments settled within several hours as storm intensity diminished. Winds and waves generated by thunderstorms were more transient than those generated by winter storms and tropical storms. Based on the data collected during this study, thunderstorms are less likely to resuspend bottom sediment than winter storms and tropical storms. Maximum tidal currents at the study sites are usually less than 15 cm s −1 and did not increase observed concentrations of suspended solids.

Florida↗

USGS1999

Fishes in mangrove prop-root habitats of northeastern Florida Bay: Distinct assemblages across an estuarine gradient

Seasonal changes in freshwater inflow and other environmental conditions may induce changes in density and species composition of mangrove fishes along estuarine gradients. Fishes within mangrove habitats in a subtropical estuary were sampled monthly from May 1989 to May 1990, using block nets with rotenone and visual censuses. At 18 stations, temperature ranged from 22 to 34°C, depth from 10 to 104cm and underwater visibility from 1 to 13m. Salinity ranged from 0 to 60 upstream, and 35 to 54 mid- and downstream. A total of 573191 individuals (76 species) was observed or collected, with an average density of 6·5 fish m −2 . Engraulidae, Atherinidae, Poeciliidae and Cyprinodontidae numerically dominated the assemblage. Distinct assemblages occurred up-, mid- and downstream and maintained coherent groups in these gradient positions over the seasons. Residents totalled 94·5% of the individuals, estuarine transients comprised 5·1% and occasional marine visitors were less than 0·4%. Densities of resident fishes peaked in winter as temperatures and water levels fell, uncorrelated with changes in salinity. These observations suggest that mangrove habitats may sustain diverse and abundant fish communities dominated by euryhaline residents. Although estuarine transients were consistently rare in upstream sub-basins, downstream were found numerous sub-adults of species occurring as adults on nearby reefs (Lutjanidae, Haemulidae). Thus, reef-associated estuarine transients may be abundant in mangrove habitats having near-marine salinities. Contrary to expectations, mangrove habitats in northeastern Florida bay did not function as a nursery as defined under the nursery-ground paradigm: young-of-the-year juveniles of estuarine transient species did not seek low salinity sub-basins. However, northeastern Florida Bay may not be representative of most mangrove estuaries as the area: (1) is without lunar tides and related circulation; (2) has low and variable amounts of submersed vegetation; and (3) experiences severe hypersaline conditions.

Estuarine, Coastal and Shelf Science↗

USGS1999

Volcanogenic Sulfur on Earth and Io: Composition and Spectroscopy

The causes of Io's variegated surface, especially the roles of sulfur, and the geochemical history of sulfur compounds on Io are not well understood. Suspecting that minor impurities in sulfur might be important, we have investigated the major and trace element chemistry and spectroscopic reflectance of natural sulfur from a variety of terrestrial volcanic-hydrothermal environments. Evidence suggests that Io may be substantially coated with impure sulfur. On Earth, a few tenths of a percent to a few percent of chalcophile trace elements (e.g., As and Se) comonly occur in sulfur and appear to stabilize material of yellow, brown, orange, and red hues, which may persist even at low temperatures. Percentage levels of chalcophile impurities are reasonably expected to occur on Io in vapor sublimate deposits and flows derived from such deposits. Such impurities join a host of other mechanisms that might explain Io's reds and yellows. Two-tenths to two percent opaque crystalline impurities, particularly pyrite (FeS2), commonly produces green, gray, and black volcanic sulfur on Earth and might explain areas of Io having deposits of these colors. Pyrite produces a broad absorption near 1 ??m that gradually diminishes out to 1.6 ??m - similar but not identical to the spectrum of Io seen in Galileo NIMS data. Percentage amounts of carbonaceous impurities and tens of percent SiO2 (as silicates) also strongly affect the spectral properties of Earth's sulfur. Io's broad absorption between 0.52 and 0.64 ??m remains unexplained by these data but could be due to sodium sulfides, as suggested previously by others, or to As, Se, or other impurities. These impurities and others, such as P and Cl (which could exist on Io's surface in amounts over 1% that of sulfur), greatly alter the molecular structure of molten and solid sulfur. Minor impurities could impact Io's geology, such as the morphology of sulfur lava flows and the ability of sulfur to sustain high relief. We have not found any natural sulfur containing significant Na beyond that attributable to silicate inclusions. In sum, the unique physical-chemical properties of S-rich systems and the strong affinity of certain elements for S may have broad implications for the appearance, spectroscopic interpretation, and geologic processes of Io. Identification of impurities in sulfur may be helpful in tracing the geochemical evolution of surface deposits on Io. Perhaps foretelling of new areas of investigation, Cl has recently been reported in the Io torus (M. Kueppers and N. M. Schneider 1999, Eos Trans.80, 5207), suggesting the presence on Io of either salts, such as halite, or sulfur chlorides. Further evidence of minor iogenic impurities should be sought in Io's neutral cloud and plasma torus as well as in further scrutiny of Io's reflectance spectra. ?? 1999 Academic Press.

Icarus↗

USGS2000

Meter-Scale Characteristics of Martian Channels and Valleys

Mars Global Surveyor images, with resolutions as high as 1.5 m pixel, enable characterization of martian channels and valleys at resolutions one to two orders of magnitude better than was previously possible. A major surprise is the near-absence of valleys a few hundred meters wide and narrower. The almost complete absence of fine-scale valleys could be due to lack of precipitation, destruction of small valleys by erosion, or dominance of infiltration over surface runoff. V-shaped valleys with a central channel, such as Nanedi Vallis, provide compelling evidence for sustained or episodic flow of water across the surface. Larger valleys appear to have formed not by headward erosion as a consequence of groundwater sapping but by erosion from water sources upstream of the observed sections. The freshest appearing valleys have triangular cross sections, with talus from opposing walls meeting at the center of the valley. The relations suggest that the width of the valleys is controlled by the depth of incision and the angle of repose of the walls. The flat floors of less fresh-appearing valleys result primarily from later eolian fill. Several discontinuous valleys and lines of craters suggest massive subsurface solution or erosion. The climatic implications of the new images will remain obscure until the cause for the scarcity of fine-scale dissection is better understood. ?? 2000 Academic Press.

Icarus↗

USGS2000

Channel incision and patterns of cottonwood stress and mortality along the Mojave River, California

In 1995, mapping and classification of riparian vegetation along the Mojave River in southern California revealed an 8-km reach in which riparian cottonwoods ( Populus fremontii Wats.) were stressed or dying. We tested a set of predictions based on the inference that cottonwood decline was an indirect result of lowered water-table levels following flood-related channel incision. Comparisons of topographic cross-sections from 1963 and 1997, indicated a net change in channel elevation between −0·71 and −3·6 m within zones of cottonwood stress and mortality. Ages of young cottonwood and willow stems adjacent to the present channel and radial stem growth of surviving cottonwoods were consistent with the inference that channel incision, associated with sustained flooding in January and February of 1993, lowered channel elevations throughout the affected reach. Well records and soil redoximorphic features indicate that channel incision caused net water-table declines ⩾1·5 m on portions of the adjacent flood plain where cottonwood stand mortality ranged between 58 and 93%. In areas where water-table declines were estimated to be <1·0 m, stand mortality was 7–13%.

Journal of Arid Environments↗

USGS1998

Evaluating landscape health: Integrating societal goals and biophysical process

Evaluating landscape change requires the integration of the social and natural sciences. The social sciences contribute to articulating societal values that govern landscape change, while the natural sciences contribute to understanding the biophysical processes that are influenced by human activity and result in ecological change. Building upon Aldo Leopold's criteria for landscape health, the roles of societal values and biophysical processes in shaping the landscape are explored. A framework is developed for indicators of landscape health and integrity. Indicators of integrity are useful in measuring biological condition relative to the condition in landscapes largely unaffected by human activity, while indicators of health are useful in evaluating changes in highly modified landscapes. Integrating societal goals and biophysical processes requires identification of ecological services to be sustained within a given landscape. It also requires the proper choice of temporal and spatial scales. Societal values are based upon inter-generational concerns at regional scales (e.g. soil and ground water quality). Assessing the health and integrity of the environment at the landscape scale over a period of decades best integrates societal values with underlying biophysical processes. These principles are illustrated in two contrasting case studies: (1) the South Platte River study demonstrates the role of complex biophysical processes acting at a distance; and (2) the Kissimmee River study illustrates the critical importance of social, cultural and economic concerns in the design of remedial action plans. In both studies, however, interactions between the social and the biophysical governed the landscape outcomes. The legacy of evolution and the legacy of culture requires integration for the purpose of effectively coping with environmental change.

Journal of Environmental Management↗