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A vision for documenting and sharing knowledge in conservation

As editors, we mark the launch of Conservation Science and Practice , a journal of the Society for Conservation Biology (SCB), with the following remarks framing the purpose and aspirations of the journal. Our aim is to share scholarship on and experiences of the practice of conservation. We define conservation practice as the application of conservation principles or theory across conservation issues, from planning and directly managing nature to influencing public policy and private behaviors—at scales from local communities to international governing bodies. We are striving for Conservation Science and Practice to be a forum for sharing lessons learned from research and practice to reciprocally informing and improving both arenas.

Conservation Science and Practice

Will hunters steward wolves? A comment on Treves and Martin

As wolf conservation transitions away from federally sponsored protection and recovery toward sustainable management under state fish and game agencies, researchers and policymakers are interested to know what role hunters will play. Based upon hunters' responses to three recent surveys in Wisconsin and the northern Rockies, Treves and Martin question the assumption that hunters will steward wolves, noting that the majority of hunters that responded were unsupportive of wolf conservation. However, this conclusion largely depends upon what is meant by stewardship and what actions are required for wolves to be conserved. This article discusses the meaning of three concepts either explicitly or implicitly discussed by Treves and Martin—tolerance, acceptance, and stewardship—and offers a conceptual model of wildlife conservation behavior that clarifies the relationship among these concepts.

Society & Natural Resources: An International Jour

The Chesapeake Bay Land Change Model (CBLCM): Simulating future land use scenarios and potential impacts on water quality

The Chesapeake Bay Land Change Model (CBLCM) is an open-source pseudo-cellular automata land change model tailored for loose coupling with watershed models. The CBLCM simulates infill development, residential and commercial development, natural land and agricultural land conversion, and growth served by sewer or septic wastewater treatment. The CBLCM is unique among land change models by simulating multiple types of development and explicitly accounting for infill development and the spatial patterns of development densities. The CBLCM was used to simulate five future land use scenarios, holding population constant, for all counties within and adjacent to the Chesapeake Bay watershed from 2013 to 2055. Results are presented here for the state of Maryland over the period 2013–2025 to illustrate model functionality and validation. The growth management (GM) scenario achieved the least development and potential impacts to natural and agricultural lands while accommodating the same amount of population growth as the other four scenarios. Scenarios focusing exclusively on natural or agricultural land protection shifted development to unprotected areas resulting in unforeseen water quality consequences. Simultaneously achieving more compact development while protecting the most valued natural and agricultural lands requires a combination of GM and land conservation policies and actions.

Maryland

Prioritizing bottomland hardwood forest sites for protection and augmentation

Bottomland hardwood forest has been greatly diminished by conversion to agriculture. Less than 25% of the pre-Columbian bottomland hardwood forests remain in the southeastern United States. Because of the valuable ecological and hydrological functions performed by these forests, their conservation and restoration has been a high priority. Part of these restoration efforts has focused on developing tools that can be used for both assessments at the landscape level and policy implementation at the local level. The distribution of bottomland hardwood forests in the Cache and White River watersheds in eastern Arkansas were examined using existing GIS databases. Criteria were developed to select areas that should be conserved or augmented for wildlife habitat. Over 67% of the study area was classified as agriculture, with bottomland hardwood forest the next largest habitat class. The thickness of a forest fragment was defined as the radius of the largest circle that can be inscribed in a fragment. Thickness was used in three ways. First, individual forest fragments were identified and selected based on ecological function using criteria we established. Second, individual fragments that were too small to support interior species, but large enough that if moderately augmented they could recover that function, were identified and selected. These augmentable fragments were further prioritized by adjacency to habitat that might be suitable for reforestation, namely agriculture. Third, watersheds were prioritized for conservation and augmentation based on the size and distributions of forest fragment thickness and area within each watershed.

Arkansas

Picking up the pieces: Conserving remnant natural areas in the post-industrial landscape of the Calumet Region

The Calumet Region was shaped by geologic forces, succession, and interacting biomes converging on a unique natural landscape. Over the past 4500 years, a strand plain has formed to the north of a geologic area called Toleston Beach. Sequential and differential primary succession of dune and swale communities in this region allowed species from different biomes to interact freely. In the mid-nineteenth century, commerce and settlement drastically changed the area, and natural areas were fragmented, manipulated, and degraded by cultural intrusions and industrialization. Despite the near obliteration of dune and swale habitat, small fragments of natural land escaped destruction. These native fragments maintained some semblance of the landscape that once covered the region. Currently, these native fragments are threatened by the lingering intrusion of historic contamination and the continuing presence of industry and commerce. Restoration and conservation of these remnants will need to be a process of integrating biological diversity goals into the landscape of the industrialized region through planning and design. We outline here the natural history of the region, the philosophical rationale for conservation, and possible approaches for integrating and maintaining these valuable remnant resources and processes.

Illinois, Indiana, Michigan

Mangrove forest distributions and dynamics (1975–2005) of the tsunami-affected region of Asia

Aim We aimed to estimate the present extent of tsunami-affected mangrove forests and determine the rates and causes of deforestation from 1975 to 2005. Location Our study region covers the tsunami-affected coastal areas of Indonesia, Malaysia, Thailand, Burma (Myanmar), Bangladesh, India and Sri Lanka in Asia. Methods We interpreted time-series Landsat data using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of plus-or-minus half a pixel, an accuracy necessary for change analysis. Each image was normalized for solar irradiance by converting digital number values to the top-of-the atmosphere reflectance. Ground truth data and existing maps and data bases were used to select training samples and also for iterative labelling. We used a post-classification change detection approach. Results were validated with the help of local experts and/or high-resolution commercial satellite data. Results The region lost 12% of its mangrove forests from 1975 to 2005, to a present extent of c . 1,670,000 ha. Rates and causes of deforestation varied both spatially and temporally. Annual deforestation was highest in Burma ( c . 1%) and lowest in Sri Lanka (0.1%). In contrast, mangrove forests in India and Bangladesh remained unchanged or gained a small percentage. Net deforestation peaked at 137,000 ha during 1990–2000, increasing from 97,000 ha during 1975–90, and declining to 14,000 ha during 2000–05. The major causes of deforestation were agricultural expansion (81%), aquaculture (12%) and urban development (2%). Main conclusions We assessed and monitored mangrove forests in the tsunami-affected region of Asia using the historical archive of Landsat data. We also measured the rates of change and determined possible causes. The results of our study can be used to better understand the role of mangrove forests in saving lives and property from natural disasters such as the Indian Ocean tsunami, and to identify possible areas for conservation, restoration and rehabilitation.

Journal of Biogeography

Oil, gas field growth projections: Wishful thinking or reality?

The observed `field growth' for the period from 1992 through 1996 with the US Geological Survey's (USGS) predicted field growth for the same period are compared. Known field recovery of field size is defined as the sum of past cumulative field production and the field's proved reserves. Proved reserves are estimated quantities of hydrocarbons which geologic and engineering data demonstrate with reasonable certainty to recoverable from known fields under existing economic and operating conditions. Proved reserve estimates calculated with this definition are typically conservative. The modeling approach used by the USGS to characterize `field growth phenomena' is statistical rather that geologic in nature.

Oil & Gas Journal

Derivation of solute-transport equations for a turbulent natural-channel flow

The continuity equation of water and the convection-diffusion equation for a solute are derived by use of an orthogonal curvilinear (natural) coordinate system, which follows the meandering and irregular pattern of natural channel geometry. The solute is assumed to be neutrally buoyant, conservative, and passive. The three-, two-, and one-dimensional equations derived herein represent one of the most satisfactory descriptions of solute transport by turbulent flow in a natural channel.

Journal of Research of the U.S. Geological Survey

Effect of passive acoustic sampling methodology on detecting bats after declines from white nose syndrome

Concomitant with the emergence and spread of white-nose syndrome (WNS) and precipitous decline of many bat species in North America, natural resource managers need modified and/or new techniques for bat inventory and monitoring that provide robust occupancy estimates. We used Anabat acoustic detectors to determine the most efficient passive acoustic sampling design for optimizing detection probabilities of multiple bat species in a WNS-impacted environment in New York, USA. Our sampling protocol included: six acoustic stations deployed for the entire duration of monitoring as well as a 4 x 4 grid and five transects of 5-10 acoustic units that were deployed for 6-8 night sample durations surveyed during the summers of 2011-2012. We used Program PRESENCE to determine detection probability and site occupancy estimates. Overall, the grid produced the highest detection probabilities for most species because it contained the most detectors and intercepted the greatest spatial area. However, big brown bats ( Eptesicus fuscus ) and species not impacted by WNS were detected easily regardless of sampling array. Endangered Indiana ( Myotis sodalis ) and little brown ( Myotis lucifugus ) and tri-colored bats ( Perimyotis subflavus ) showed declines in detection probabilities over our study, potentially indicative of continued WNS-associated declines. Identification of species presence through efficient methodologies is vital for future conservation efforts as bat populations decline further due to WNS and other factors.

Journal of Ecology and the Natural Environment

Nitrate fate and transport through current and former depressional wetlands in an agricultural landscape, Choptank Watershed, Maryland, United States

Understanding local groundwater hydrology and geochemistry is critical for evaluating the effectiveness of wetlands at mitigating agricultural impacts on surface waters. The effectiveness of depressional wetlands at mitigating nitrate (NO 3 ) transport from fertilized row crops, through groundwater, to local streams was examined in the watershed of the upper Choptank River, a tributary of Chesapeake Bay on the Atlantic Coastal Plain. Hydrologic, geochemical, and water quality data were collected from January of 2008 through December of 2009 from surface waters and networks of piezometers installed in and around current or former depressional wetlands of three major types along a gradient of anthropogenic alteration: (1) natural wetlands with native vegetation (i.e., forested); (2) prior-converted croplands, which are former wetlands located in cultivated fields; and (3) hydrologically restored wetlands, including one wetland restoration and one shallow water management area. These data were collected to estimate the orientation of groundwater flow paths and likely interactions of groundwater containing NO 3 from agricultural sources with reducing conditions associated with wetlands of different types. Natural wetlands were found to have longer periods of soil saturation and reducing conditions conducive to denitrification compared to the other wetland types studied. Because natural wetlands are typically located in groundwater recharge areas along watershed divides, nitrogen (N) from nearby agriculture was not intercepted. However, these wetlands likely improve water quality in adjacent streams via dilution. Soil and geochemical conditions conducive to denitrification were also present in restored wetlands and prior-converted croplands, and substantial losses of agricultural NO 3 were observed in groundwater flowing through these wetland sediments. However, delivery of NO 3 from agricultural areas through groundwater to these wetlands resulting in opportunities for denitrification were limited, particularly where reducing conditions did not extend throughout the entire thickness of the surficial aquifer allowing NO 3 to pass conservatively beneath a wetland along deeper groundwater flow paths. The complexity of N fate and transport associated with depressional wetlands complicates the understanding of their importance to water quality in adjacent streams. Although depressional wetlands often contribute low NO 3 water to local streams, their effectiveness as landscape sinks, for N from adjacent agriculture varies with natural conditions, such as the thickness of the aquifer and the extent of reducing conditions. Measurement of such natural geologic, hydrologic, and geochemical conditions are therefore fundamental to understanding N mitigation in individual wetlands.

Maryl

Assessing conservation and management actions with ecosystem services better communicates conservation value to the public

Fish and wildlife populations are under unprecedented threats from changes in land use and climate. With increasing threats comes a need for an expanded constituency that can contribute to the public support and financial capital needed for habitat conservation and management. Using an ecosystem services approach can provide a framework for a more holistic accounting of conservation benefits. Our objective here is to provide a greater understanding of the role that taking an ecosystem services approach can have in expanding the public constituency that supports the use of financial capital required to conserve and manage the nation’s natural capital. To demonstrate a methodology and the usefulness of taking an ecosystem services approach when communicating the value of conserving and managing fish and wildlife habitats, we performed an evaluation of U.S. Fish and Wildlife Service-owned Waterfowl Production Areas, National Wildlife Refuges, and easement lands (both wetland and grassland) in Stutsman County, North Dakota. We quantified amphibian habitat, grassland bird habitat, floral resources for pollinators, and carbon storage services under various scenarios of conservation. While we did not include all possible ecosystem services in our model, our case study shows how this process can provide a more complete picture of the collateral benefits of conservation directed primarily toward waterfowl. Using this ecosystem services approach, we documented marked losses in all services modeled if current conservation lands were developed for the production of agricultural crops. By having access to a more complete picture of benefits provided by conservation lands, decision makers can better communicate their value. By garnering greater public support through a more accurate accounting of societal benefits, conservation and management of dwindling natural capital may someday attain the same level of thought and consideration that is put into the conservation and management of the nation’s financial capital.

North Dakota

Distribution and conservation status of coastal sage scrub in southwestern California

A landscape-based characterization of vegetation has been developed for southwestern California using satellite imagery, air photos, existing vegetation maps, and field data. Distribution maps of nine dominant coastal scrub species and 13 species assemblages that were identified by divisive information analysis have been analyzed to quantify spatial patterns of species co-occurrence. Three general distribution patterns are identified that suggest the Diegan, Ventaran and Riversidian Associations identified by other workers. Vegetation data have also been related to land ownership and management to assess the conservation status of upland plant communities. A large proportion of the mapped distribution of species and vegetation types is on private land, and several taxa show less than 4 % of mapped distribution in nature reserves. The analysis highlights the need to extend current conservation planning efforts into the northern part of the region to encompass areas where Salvia leucophylla is a frequent community dominant.

Journal of Vegetation Science

Point- and nonpoint-source trace elements in a wild and scenic river of northern New Mexico.

Variations in water quality of the upper Rio Grande and Red River are presented. A downstream increase in concentrations of various constituents, at times approaching or exceeding water quality standards, occurred due to leaching of natural ore bodies and permitted discharges from molybdenum mill tailings ponds. Nonpoint sources are a major cause of elevated trace element concentrations.-from Author

Journal of Soil and Water Conservation

Conservation of northwestern and southwestern pond turtles: Threats, population size estimates, and population viability analysis

Accurate status assessments of long-lived, widely distributed taxa depend on the availability of long-term monitoring data from multiple populations. However, monitoring populations across large temporal and spatial scales is often beyond the scope of any one researcher or research group. Consequently, wildlife managers may be tasked with utilizing limited information from different sources to detect range-wide evidence of population declines and their causes. When assessments need to be made under such constraints, the research and management communities must determine how to extrapolate from variable population data to species-level inferences. Here, using three different approaches, we integrate and analyze data from the peer-reviewed literature and government agency reports to inform conservation for northwestern pond turtles (NPT) Actinemys marmorata and southwestern pond turtles (SPT) Actinemys pallida . Both NPT and SPT are long-lived freshwater turtles distributed along the west coast of the United States and Mexico. Conservation concerns exist for both species; however, SPT may face more severe threats and are thought to exist at lower densities throughout their range than NPT. For each species, we ranked the impacts of 13 potential threats, estimated population sizes, and modeled population viability with and without long-term droughts. Our results suggest that predation of hatchlings by invasive predators, such as American bullfrogs Lithobates catesbeianus and Largemouth Bass Micropterus salmoides, is a high-ranking threat for NPT and SPT. Southwestern pond turtles may also face more severe impacts associated with natural disasters (droughts, wildfires, and floods) than do NPT. Population size estimates from trapping surveys indicate that SPT have smaller population sizes on average than do NPT ( P = 0.0003), suggesting they may be at greater risk of local extirpation. Population viability analysis models revealed that long-term droughts are a key environmental parameter; as the frequency of severe droughts increases with climate change, the likelihood of population recovery decreases, especially when census sizes are low. Given current population trends and vulnerability to natural disasters throughout their range, we suggest that conservation and recovery actions first focus on SPT to prevent further population declines.

Journal of Fish and Wildlife Management

Population genetics of Gunnison sage-grouse: Implications for management

The newly described Gunnison sage-grouse ( Centrocercus minimus ) is a species of concern for management because of marked declines in distribution and abundance due to the loss and fragmentation of sagebrush habitat. This has caused remaining populations to be unusually small and isolated. We utilized mitochondrial DNA sequence data and data from 8 nuclear microsatellites to assess the extent of population subdivision among Gunnison sage-grouse populations in southwestern Colorado and southeastern Utah, USA. We found a high degree of population structure and low amounts of gene flow among all pairs of populations except the geographically adjacent Gunnison and Curecanti populations. Population structure for Gunnison sage-grouse was significantly higher than has been reported for greater sage-grouse ( C. urophasianus ). Further, we documented low levels of genetic diversity in some populations (particularly Dove Creek/Monticello and Piñon Mesa with an average of only 3.00 and 2.13 alleles per locus respectively) indicating that translocations from larger, more genetically diverse populations may be warranted. Bayesian analysis identified 3 potential migrants (involving San Miguel, Dove Creek/Monticello, Crawford, and Curecanti). Further, this analysis showed that 4 individuals from Cerro/Cimarron were more closely related to birds from San Miguel than to its geographically closer neighbors Gunnison and Curecanti. This suggests the Cerro/Cimarron area may act as a stepping stone for gene flow between San Miguel and Gunnison and that habitat restoration and protection in areas between these 2 basins should be a priority in an attempt to facilitate natural movement among these populations. Conservation plans should include monitoring and maintaining genetic diversity, preventing future habitat loss and fragmentation, enhancing existing habitat, and restoring converted sagebrush communities.

Journal of Wildlife Management

Consolidation drainage and climate change may reduce Piping Plover habitat in the Great Plains

Many waterbird species utilize a diversity of aquatic habitats; however, with increasing anthropogenic needs to manage water regimes there is global concern over impacts to waterbird populations. The federally threatened Piping Plover (Charadrius melodus; hereafter plovers) is a shorebird that breeds in three habitat types in the Prairie Pothole Region of North Dakota, South Dakota, and Canada: riverine sandbars; reservoir shorelines; and prairie wetlands. Water surface areas of these habitats fluctuate in response to wet-dry periods; decreasing water surface areas expose shorelines that plovers utilize for nesting. Climate varies across the region so when other habitats are unavailable for plover nesting because of flooding, prairie wetlands may periodically provide habitat. Over the last century, many of the wetlands used by plovers in the Prairie Pothole Region have been modified to receive water from consolidation drainage (drainage of smaller wetlands into another wetland), which could eliminate shoreline nesting habitat. We evaluated whether consolidation drainage and fuller wetlands have decreased plover presence in 32 wetlands historically used by plovers. We found that wetlands with more consolidation drainage in their catchment and wetlands that were fuller had a lower probability of plover presence. These results suggest that plovers could have historically used prairie wetlands during the breeding season but consolidation drainage and/or climate change have reduced available shoreline habitat for plovers through increased water levels. Prairie wetlands, outside of some alkali wetlands in the western portion of the region, are less studied as habitat for plovers when compared to river and reservoir shorelines. Our study suggests that these wetlands may have played a larger role in plover ecology than previously thought. Wetland restoration and conservation, through the restoration of natural hydrology, may be required to ensure that adequate habitat exists among the three habitat types in the face of existing or changing climate and to ensure long-term conservation.

North Dakota

Sequoia and Sequoiadendron: Two paleoendemic megatrees with markedly different adaptive responses to recent high-severity fires

Premise Coast redwood ( Sequoia sempervirens ) and giant sequoia ( Sequoiadendron giganteum ) are two iconic paleoendemic species with limited distributions, well known for their spectacular size. Recently, they have been exposed to high-severity crown fires, with starkly contrasting responses. Methods We used all available published literature and field observations to understand the responses to fire in an evolutionary context. Results Coast redwoods, found in California's coastal rainforests, were highly resilient to high-severity fires, with most trees surviving due to their ability to resprout from the base and trunk, though seedling regeneration was largely lacking. In contrast, giant sequoias, native to the Sierra Nevada, do not resprout, leading to significant tree mortality after very high-severity fires; they released seeds only in patches where some trees survived moderately high-severity fires. Conclusions These high-severity fires were novel events for giant sequoias, but not for coast redwoods. Fire suppression has disrupted the natural fire regime in the giant sequoia ecosystem by preventing frequent lightning-caused surface fires, resulting in high-severity fires that killed a substantial number of these giants. In coast redwood forests, infrequent but high-severity crown fires were the norm before burning by Native Americans. Frequent, low-severity burning by Native Americans over the past few hundred years was localized and 20 th -century fire suppression has returned the natural fire regime to these forests. The recent crown fires do not represent a threat to redwood conservation; however, other management goals may require emulating Native American burning practices and in some cases may be best termed cultural restoration.

American Journal of Botany

Bayesian adaptive survey protocols for resource management

Transparency in resource management decisions requires a proper accounting of uncertainty at multiple stages of the decision‐making process. As information becomes available, periodic review and updating of resource management protocols reduces uncertainty and improves management decisions. One of the most basic steps to mitigating anthropogenic effects on populations is determining if a population of a species occurs in an area that will be affected by human activity. Species are rarely detected with certainty, however, and falsely declaring a species absent can cause improper conservation decisions or even extirpation of populations. We propose a method to design survey protocols for imperfectly detected species that accounts for multiple sources of uncertainty in the detection process, is capable of quantitatively incorporating expert opinion into the decision‐making process, allows periodic updates to the protocol, and permits resource managers to weigh the severity of consequences if the species is falsely declared absent. We developed our method using the giant gartersnake ( Thamnophis gigas ), a threatened species precinctive to the Central Valley of California, as a case study. Survey date was negatively related to the probability of detecting the giant gartersnake, and water temperature was positively related to the probability of detecting the giant gartersnake at a sampled location. Reporting sampling effort, timing and duration of surveys, and water temperatures would allow resource managers to evaluate the probability that the giant gartersnake occurs at sampled sites where it is not detected. This information would also allow periodic updates and quantitative evaluation of changes to the giant gartersnake survey protocol. Because it naturally allows multiple sources of information and is predicated upon the idea of updating information, Bayesian analysis is well‐suited to solving the problem of developing efficient sampling protocols for species of conservation concern.

California