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This paper examines the processes by which "stakeholder" status is constructed, and the importance of sense of place to that construction in collaborative water resource governance processes. Water management often involves collaborative governance, but there can be differences between who has an interest in the outcome, and who is formally invited to participate as a "stakeholder." We examine a case study of a collaborative water governance process in Central Oregon, and found that existing models of stakeholder formation present in scholarly literature did not fully explain the dynamics of stakeholder participation. We propose a two-step "Interest-Participation" model of stakeholder formation: to be considered stakeholders, a group must not only have an interest in the outcome but must actively navigate barriers to participation. We moreover argue that collaborative engagement is an embodiment of sense of place, emphasizing the importance of competing place meanings in resource governance processes. [ABSTRACT FROM AUTHOR]

The Edwards Aquifer is the primary source of water for a region in South-Central Texas that includes San Antonio and irrigated agriculture to the west. The aquifer also contributes to surface water flow in the Guadalupe River through Comal and San Marcos Springs, which are home to endangered aquatic species. In 1956, during the multiyear Texas drought of record, Comal Springs ceased to flow initiating a multi-decadal transboundary water dispute over the aquifer. This dispute pitted urban, agricultural, and environmental interests and surface water right holders against one another. In 1993, a federal district court ruled that the Endangered Species Act required that adequate flows from the springs be ensured for the endangered species. The Texas Legislature responded to the court by establishing the Edwards Aquifer Authority to regulate groundwater withdrawals. In 2007, with a key deadline looming to create a species protection plan, the Texas Legislature intervened again and mandated that the rival regional water interests engage in a stakeholder process to develop the plan. That process, which was called the Edwards Aquifer Recovery Implementation Program, resulted in a diverse group of parties with opposing interests collaborating to develop, approve, fund, and implement the landmark Edwards Aquifer Habitat Conservation Plan, which is in its 10th year of implementation. [ABSTRACT FROM AUTHOR]

Timber harvesting and related management practices associated with industrial timberlands have changed dramatically in the last two decades. Industrial timberlands are now more carefully assessed and mitigated. Recent studies of mass wasting in northern California included a review of historical aerial photographs from the early 1940s through 2016 and field measurements of nearly 3,000 shallow landslides on industrially managed timberlands. Significant improvements have been seen in management practices over time that include but are not limited to reduced harvest unit sizes, increased streamside tree retention, reduced road density, and improved road-building practices. These improvements are a result of a variety of sources such as evolving state regulations, voluntary conservation plans, and increased professional oversight. Subsequently, significant decreases in management-related erosion are being observed across the area included in this study. Observations show that improvements in management practices have positively affected regional mass wasting. In this investigation, significant changes have been noted in both causal mechanisms and landslide erosion rates. The study data shows that before the year 2000, nearly 85 percent of landslide-related erosion was determined to be the result of historical logging, either by harvesting or from roads (generally poor design and/or location). Shallow landslide erosion rates have varied over the duration of time reviewed for this study, peaking in the 1970s. Since 2000, erosion rates across the study area have decreased to 20 m3/km2/yr, which is a 92 percent reduction compared with the historical rate. [ABSTRACT FROM AUTHOR]

Injury and mortality of night flying seabirds due to lights (fallout) affects their long-term viability. However, the cryptic nature of these species hinders direct estimates and projections of fallout. The Kauaʻi Seabird Habitat Conservation Plan (KSHCP) characterizes the current and projected fallout for Newell's shearwaters (Puffinus auricularis newelli), Hawaiian petrels (Pterodroma sandwichensis) and the Hawaiʻi distinct population segment of the band-rumped storm-petrels (Oceanodroma castro) on the island of Kauaʻi across eight permittees. In the KSHCP, each permittee was required to itemize the lighting infrastructure related to their facilities (type, wattage, number of lights, etc.) as well as supply an overall expected seabird fallout number with an estimate of detection probability or ability to find the fallout birds. Light intensity is thought to be correlated to the degree of attraction to a light source. Here we identify seabird fallout using indirect estimates derived from the KSHCP and present a reproducible method to consistently project and calculate fallout between entities that need to reduce seabird mortality due to their light sources. Though the permittees did not provide an estimate of light intensity at their sites, we extrapolated luminous intensity (light brightness) from their itemized light information (i.e., lumens/watt). Using luminous intensity, we then derived the degree of fallout per lumen and its variation across the permittees. As a proof of concept, we then projected the fallout per lumen estimate onto streetlights owned by the Kauaʻi Island Utility Cooperative, as applied over a range of detectability correction factors. Though fallout varies significantly based on the detectability correction factor used, when considering the site differences on Kauaʻi, a previous fallout estimate, and the overlapping characteristics of the projected versus actual luminous intensities, the utilities projected fallout appears applicable. We feel that the methodology can be used as a baseline to infer fallout associated with various entities.

Management of vulnerable amphibian populations requires a better understanding of the habitat factors that will make the greatest difference in their preservation. We set out to develop a predictive model of amphibian abundance based on habitat characteristics that may influence their survival and persistence. Our study system was the Sonoma County California tiger salamander (Ambystoma californiense; SCTS), an amphibian threatened by habitat loss and fragmentation. In 2019, 298 ponds (almost every breeding pond in this federally endangered Distinct Population Segment) were surveyed to determine SCTS larval densities, a proxy for population well-being. We used model selection to identify which factors of pool morphology, the surrounding pool neighborhood, and terrestrial upland habitat best predict variation in larval densities. Our best model showed a significant positive relationship between larval SCTS densities and three variables: pool depth, number of breeding pools within 500 m of a focal pool, and amount of suitable and accessible upland habitat within 1500 m of a pool. To further refine this model, we then examined interactions and non-linearities using a generalized additive model. Based on this refined model, we simulated a variety of management scenarios to identify which management practices would most increase larval densities across the endangered Distinct Population Segment and where on the landscape employing each mitigation action would yield the greatest return. This provides the basis for a county-wide Habitat Conservation Plan for SCTS, and highlights habitat characteristics likely critical to the conservation of other pond-breeding amphibians., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Aidan O'Brien reports financial support was provided by Sonoma County Government. Christopher Searcy reports financial support was provided by Sonoma County Government. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Habitat Conservation Plans (HCPs) commonly facilitate habitat conservation on private land in the United States, yet the effectiveness of individual HCPs is rarely evaluated. Here, we assess the effectiveness of a high-profile HCP created by a lumber company to protect old-growth forests used for breeding by Marbled Murrelets (Brachyramphus marmoratus) on private land. We used 17 years of HCP-monitoring data to compare trends in murrelet occupancy and inland counts between private HCP areas and public reference areas over time. Based on occupancy models applied to audio-visual survey data, average occupancy was higher in public reference areas (0.85; 85% confidence intervals [CI]: 0.79-0.90) than in private HCP areas (0.46; 85% CI: 0.38-0.54). Numerically, trends in occupancy were slightly positive in public areas (= 1.01; 85% CI: 0.94-1.08) and slightly negative in private areas (= 0.97; 85% CI: 0.87-1.06), but CI did not preclude stable occupancy on both ownerships. Based on generalized linear mixed models applied to inland radar survey data, murrelet counts in private HCP areas (least-squares [LS] mean = 8.7; 85% CI: 6.2-12.2) were lower than those in public reference areas (LS mean = 14.8; 85% CI: 10.1-21.7), but CI overlapped. Murrelet counts declined by 12-17% annually on both ownerships over the study period based on the top model, but a closely competing interactive model suggested more rapid declines in public reference (14-20%) than in private HCP (10-15%) areas. Both models indicated that murrelet counts were negatively related to sea surface temperature, suggesting that warm ocean conditions negatively affect murrelet breeding effort. Collectively, these results suggest that while HCP habitat may be lower quality than public reference areas, the HCP has likely not exacerbated ongoing declines of murrelets in the region. This work highlights the importance of including reference areas when evaluating conservation policies. [ABSTRACT FROM AUTHOR]

Most species face multiple anthropogenic disruptions. Few studies have quantified the cumulative influence of multiple threats on species of conservation concern, and far fewer have quantified the potential relative value of multiple conservation interventions in light of these threats. We linked spatial distribution and population viability models to explore conservation interventions under projected climate change, urbanization, and changes in fire regime on a long-lived obligate seeding plant species sensitive to high fire frequencies, a dominant plant functional type in many fire-prone ecosystems, including the biodiversity hotspots of Mediterranean-type ecosystems. First, we investigated the relative risk of population decline for plant populations in landscapes with and without land protection under an existing habitat conservation plan. Second, we modeled the effectiveness of relocating both seedlings and seeds from a large patch with predicted declines in habitat area to 2 unoccupied recipient patches with increasing habitat area under 2 projected climate change scenarios. Finally, we modeled 8 fire return intervals (FRIs) approximating the outcomes of different management strategies that effectively control fire frequency. Invariably, long-lived obligate seeding populations remained viable only when FRIs were maintained at or above a minimum level. Land conservation and seedling relocation efforts lessened the impact of climate change and land-use change on obligate seeding populations to differing degrees depending on the climate change scenario, but neither of these efforts was as generally effective as frequent translocation of seeds. While none of the modeled strategies fully compensated for the effects of land-use and climate change, an integrative approach managing multiple threats may diminish population declines for species in complex landscapes. Conservation plans designed to mitigate the impacts of a single threat are likely to fail if additional threats are ignored.

Habitat mitigation frequently leads to planting of new habitat, assuming that it can replace lost natural habitat. Yet this practice has rarely been examined in detail. In the USA habitat mitigation is frequently allowed under the US Endangered Species Act, providing monitoring reports which represent a potentially valuable data source for imperiled species. We used publicly available reports for the US threatened Valley elderberry longhorn beetle (Desmocerus californicus dimorphus) to assess record keeping practices used by US Fish and Wildlife Service (FWS), and the utility of such analyses for improving conservation. A large portion of mitigation reports known to exist were missing from FWS files, indicating problems with data management, and a loss of important information. Transplanted brought mature beetle host plants and beetles to sites, promoting beetle colonization. Conversely, few sites with seedlings were colonized. Results indicate a need for improved data management by FWS and longer term monitoring.

Abstract Amid rapid population growth, the fate of many threatened and endangered (T&E) species in the Southeast is closely tied to conservation actions on private lands. Therefore, it is critical to understand how the public values wildlife and public attitudes toward T&E species and management approaches, such as Habitat Conservation Plans (HCPs) - a voluntary approach for private landowners to comply with the Endangered Species Act (ESA). We conducted a mail survey to examine attitudes toward T&E species and HCPs, as well as wildlife value orientations (WVOs), among the general public in four study locations in the Southeast: Charlotte Co. (FL), Cumberland Co. (TN), the Etowah Watershed (GA), and the Lower Flint River Basin (GA). Overall, respondent attitudes toward T&E species and the ESA were positive. However, respondents did not believe the U.S. Fish and Wildlife Service would make good decisions regarding endangered species management without public input. Species attitudes, WVOs and ESA knowledge were all significant influences on public support for the ESA; and species attitudes, beliefs about involvement of local communities, and support for the ESA significantly influenced perceptions about HCPs. We conclude that HCPs represent an opportunity to capitalize on support for T&E species and rebuild trust in the U.S. Fish and Wildlife Service by engaging the public in endangered species management. Highlights • Threatened and endangered species attitudes influence support for the Endangered Species Act. • Limited trust exists that federal agencies make good decisions absent public input. • Agencies could build trust by engaging the public in endangered species management. [ABSTRACT FROM AUTHOR]

Over half of the endangered species in the United States depend on private lands for habitat. In 1982, Congress amended the Endangered Species Act (ESA) to address the conservation of endangered species on private lands through the introduction of Habitat Conservation Plans (HCPs). HCPs enable landowners to comply with the ESA and can foster creative partnerships between the federal government and local stakeholders. Researchers have investigated the scientifically biological merits of HCPs, but comparatively little attention has been given to social aspects despite an emphasis on stakeholder involvement in HCPs. We explore stakeholder perceptions of HCP development through 19 semi-structured key informant interviews. Findings include the influence of interpersonal themes, shared understanding and capacity on process outcomes, and the importance of the external context in which HCP development occurs. Our research highlights the central role of understanding social dimensions to achieve the desired outcomes from collaborative conservation planning processes. [ABSTRACT FROM AUTHOR]

Abstract Wildlife biologists are undoubtedly familiar with the decades‐long debate over the Endangered Species Act and the conflicts that often arise among people of differing interests when a species is listed as federally threatened or endangered. One example that made local and national headlines in the 1990s was the golden‐cheeked warbler (Setophaga chrysoparia), which breeds exclusively in central Texas, USA, and primarily on private lands. The inclusion of the warbler on the federal endangered species list in 1990 prompted conflict between land developers, environmentalists, ranchers, and the U.S. Fish and Wildlife Service. Miscommunication and mistrust among the groups resulted in purposeful destruction of habitat and delayed or lost opportunities for species' conservation and scientific research. Now, 20 years later, we have taken the opportunity to review some of the events and conflicts surrounding the listing of the warbler such that a new generation of researchers and biologists can understand the progress made and identify where additional work may be needed. The significance of threatened and endangered species conservation varies among people and places; thus, there will be a continual need for agencies and biologists to develop relationships with local communities formed around understanding the values and motivations of all stakeholders, in an effort to limit conflict and create an atmosphere that promotes cooperative approaches to research on, and recovery of, at‐risk species. © 2012 The Wildlife Society.

On December 28, 2011, the Edwards Aquifer Authority’s Board of Directors approved the recommendations of the Edwards Aquifer Recovery Implementation Program with respect to a historic Habitat Conservation Plan. The Habitat Conservation Plan could resolve decades of acrimonious rancor and litigation over the use of the Edwards Aquifer. It provides the protection required by the federal Endangered Species Act for 8 listed species stemming from the use of the Edwards Aquifer and associated Comal and San Marcos springs while recognizing the region’s ever-growing need for water. The plan was developed by a diverse group of stakeholders through a consensus-based process and submitted to the U.S. Fish and Wildlife Service on January 5, 2012, in support of the Edwards Aquifer Recovery Implementation Program’s application for an Incidental Take Permit. The U.S. Fish and Wildlife Service noticed the availability of the Draft Environmental Impact Statement for public comment and conducted 7 public meetings to receive public comment. The public comment period closed on October 18, 2012. On February 15, 2013, the U. S. Fish and Wildlife Service issued its Record of Decision approving the issuance of the Incidental Take Permit and the Habitat Conservation Plan. This paper discusses the history of the dispute over the use of the aquifer, previous attempts to resolve the dispute, the strategic plan for protecting the aquifer, and the decision-making process used to develop the plan. Citation: Gulley RL, Cantwell JB. 2013. The Edwards Aquifer Water Wars: The Final Chapter? Texas Water Journal. 4(1):1-21. Available from: https://doi.org/10.21423/twj.v4i1.6423.

The past quarter century has witnessed a 'quieter revolution' in land-use management in the United States, from top-down regulation and adversarial environmentalism to multistakeholder collaboration and voluntary market-based mechanisms designed to forge a compromise between nature protection, property rights, and local livelihoods. The latter approach has become hegemonic, and yet this dramatic shift has received little attention from political ecologists. In this paper I argue that two contradictory lessons on the topic can be drawn from political ecology. On the one hand, proponents of the 'quieter revolution' invoke themes and normative stances shared by political ecologists, celebrating self-management by place-based communities drawing on local knowledge, in opposition to control by central governments and powerful environmental groups wielding 'big science'. On the other hand, the 'quieter revolution' exemplifies the neoliberalization of nature, which political ecologists have critiqued as providing a 'stamp of environmental approval' for capitalist expansion, often at the expense of the nature values it claims to defend. Thus, the 'quieter revolution' exposes tensions in the application of the Third-World-based political ecology orientation to a First World setting. I explore these tensions through a case study of voluntary and collaborative approaches (specifically, transfer of development rights and habitat conservation planning) in exurban Collier County in southwest Florida. I argue that in this context, it is more useful to focus on the neoliberalization of nature than on the valorization of local knowledge and control, because the discourse of local knowledge and livelihoods aligns with the (anti-environmental) interests of locally powerful actors. These power relations-and the limits of deeply embedded assumptions that undergird the political ecology literature-are revealed most effectively through ethnographic examination of the micropolitics of particular cases. [ABSTRACT FROM AUTHOR]

Abstract: Safe fish passage through hydroprojects is of paramount importance in the Pacific Northwest of the United States where anadromous runs of salmon smolts pass through as many as nine dams on the Columbia River on their way to the ocean. Minimum survival standards through the dams or hydroprojects (i.e., reservoir and dam) have been established by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion or by Habitat Conservation Plans (HCPs) in order to protect salmon stocks. These federal requirements have prompted the need to conduct scientifically and statistically rigorous and precise smolt survival studies at federally and publicly operated hydroprojects throughout the Snake-Columbia River Basin. Successful studies have been the cooperative results of regulators, hydro managers, fish biologists, engineers, and biometricians working together to conduct these high value investigations. Rock Island Dam, Washington, is used as a case study where a total of 17 release-recapture studies were conducted over a nine-year period on three salmonid species to assess compliance with HCP survival standards. [Copyright &y& Elsevier]

• Premise of the study: Despite numerous recommendations for various aspects of the design and monitoring of habitat conservation plans, there remains a need to synthesize existing guidelines into a comprehensive scheme and apply it to real-world conservation programs. • Methods: We review tools for systematic conservation planning and elements for designing and implementing ecological monitoring in an adaptive management context. We apply principles of monitoring design to the San Diego Multiple Species Conservation Program (MSCP) in California, USA--one of the first multispecies habitat conservation plans, located in a landscape where high biodiversity and urban development converge. • Key results: Tools for spatial conservation planning are aimed to conserve biodiversity, often in the context of a limited budget. In practice, these methods may not accommodate legislative mandates, budgetary uncertainties, and the range of implementation mechanisms available across consortia of stakeholders. Once a reserve is implemented, the question becomes whether it is effective at conserving biodiversity, and if not, what actions are required to make it effective. In monitoring plan development, status and threats should be used to prioritize species and communities that require management action to ensure their persistence. Conceptual models documenting the state of knowledge of the system should highlight the main drivers affecting status and trends of species or communities. Monitoring strategies require scientifically justified decisions based on sampling, response, and data design. • Conclusions: Because the framework illustrated here tackles multiple species, communities, and threats at the urban-wildland interlace, it will have utility for ecosystem managers struggling to design monitoring programs. [ABSTRACT FROM AUTHOR]

This paper uses videotaping and discourse analysis to study participants' dialogue and conduct during preparation of the Coachella Valley habitat conservation plan in southern California. The research uses social worlds analysis to reveal that the plan's technical advisors did not find facts through the collective discovery of scientific truths with unitary meanings, but instead constructed facts by aligning professional visions of space, time, and agency. The validity of the resulting plan relied on its ability to be a 'boundary object', meaning different things to different groups, while simultaneously laying claim to universality and objectivity. However, its subsequent failure to satisfy an unexpected scientific peer review demonstrates the importance of anticipating downstream reception and use when developing such documents. This case study shows that planners can be epistemic mediators, creating and stabilizing technical knowledge claims that project authority by showing a responsive face to many audiences. [ABSTRACT FROM AUTHOR]

Two groups of biologists were responsible for an unprecedented delay in completing a endangered species habitat conservation plan in the Coachella Valley of southern California. While antagonism grew as each group relentlessly promoted their perspective on whether to add a few areas to the habitat preserve, their inability to resolve their differences was not simply a matter of mistrust or poor facilitation. I analyze how these biologists practiced science in a way that supported specific institutional and ecological relationships that in turn provided a setting in which each group’s biological expertise was meaningful, credible, and useful. This tight coupling between scientific practice and society meant that something was more important to these scientists than finishing the plan. For both factions of biologists, ensuring the survival of native species in the valley rested on their ability to catalyze institutional relationships that were compatible with their scientific practice. Understanding this co-production of science and the social order is a first step toward effectively incorporating different experts in negotiation and implementation of technically complex collaborative agreements. [ABSTRACT FROM AUTHOR]

Long-term monitoring programs must use informative yet cost-effective methods. Occupancy estimates that incorporate detection probabilities are used with increasing frequency to describe species status and make management recommendations. Estimating changes in the occupancy of points over time in response to management actions or environmental changes may be especially useful for management of the Palm Springs round-tailed ground squirrel (Spermophilus tereticaudus chlorus), a subspecies covered under the Coachella Valley Multiple Species Habitat Conservation Plan and Natural Community Conservation Plan. In 2002 and 2003, we estimated occupancy and detection probability of ground squirrels across lands modeled as ground squirrel habitat by the Scientific Advisory Committee for the Habitat Conservation Plan and tested a priori hypotheses about how occupancy varied among vegetation and substrate types. In the 2003 study, we asked whether these associations were affected by winter rains after the 2002 drought year. Occupancy in 2003 was estimated at 0.99 (S^E = 0.01) in Western honey mesquite (Prosopis glandulosa) on dunes and hummocks, and occupancy of the remaining modeled habitat was best described by distance to mesquite, with the occupancy probability decreasing with increasing distance from mesquite on dunes or hummocks. The best-supported model in 2002 described the distribution of ground squirrels as a function of only vegetation and substrate type. However, the best-supported models in 2003 suggested that distance to mesquite was a component of the occupancy of non-mesquite vegetation. Mesquite seems to provide high-quality habitat that can support ground squirrels at high occupancy probabilities that may breed successfully every year. In contrast, other vegetation types provide low-quality habitat that can only support ground squirrels at low occupancy probabilities that may only breed occasionally. Mesquite could be an essential refugium during drought years, and the 4 best-supported models in 2003 suggest that restoration of mesquite beginning near currently occupied mesquite patches could be critical for maintaining ground squirrel populations on the preserves. [ABSTRACT FROM AUTHOR]

Regional conservation plans are increasingly used to plan for and protect biodiversity at large spatial scales however the means of quantitatively evaluating their effectiveness are rarely specified. Multiple-species approaches, particular those which employ site-occupancy estimation, have been proposed as robust and efficient alternatives for assessing the status of wildlife populations over large spatial scales, but implemented examples are few. I used bats as a model to evaluate design considerations for the use of occupancy estimation to assess population status and habitat associations for eight species of bats covered under a regional conservation plan. Bats were one of the groups expected to benefit from a system of reserves for species associated with late-successional/old-growth (LSOG) habitat designated under the Northwest Forest Plan (NWFP). This study produced the first estimates for probabilities of occupancy and detection for bats at a regional scale. Overall probabilities of occupancy ranged from 0.586 to 0.783 and probabilities of detection ranged from 0.239 to 0.532 among the eight species modeled. Although point estimates of occupancy suggested association with NWFP habitat categories for some species, estimate precision was low. Models that assumed constant occupancy with respect to reserve- and LSOG-status were supported for most species. I used model-averaged estimates of occupancy and detection for each species to estimate survey effort necessary to meet precision targets. Occupancy estimation was best suited to species with the highest detection probabilities. Species that are rare or difficult to detect will require enhancement in survey methods or more intensive survey effort to produce meaningful estimates. Optimizing monitoring efforts to address multiple species requires tradeoffs among survey methods, levels of effort, and acceptable levels of precision. [Copyright &y& Elsevier]

Habitat Conservation Plans are a widely used strategy to balance development and preservation of species of concern and have been used in southern California, USA, to protect the coastal California gnatcatcher (Polioptila californica). Few data exist on gnatcatcher abundance and distribution, and existing data have problems with issues of closure (i.e., sampling occurs in a short enough time period such that abundance or distribution are not changing), detectability, and proper attention to probability-based sampling schemes. Thus, a habitat model has been relied upon in reserve design. California gnatcatchers are the flagship and umbrella species of many plans and we provide the first estimates that incorporate probabilistic sampling and test predictions from the habitat model. Probability of occurrence was 26% (SÊ =0.06); however, occupancy varied by modeled habitat quality with slopes ,40%, warm, and wet sagebrush habitat having higher occupancy probabilities. Interpreting abundance and occupancy probabilities by vegetation type was complicated by error detected in Geographic Information System vegetation metadata files. The slope (1.08, SÊ =0.66), temperature (0.79, SÊ =0.70), and precipitation (-2.62, SÊ; =1.21) variables associated with habitat models were stronger influences on occupancy than was patch size (0.48, SÊ =0.66). Previous models weight patch size equal to slope and climate. Our work demonstrates that probabilistic sampling can be carried out on a large scale and the results provide better information for managers to make decisions about their reserves. [ABSTRACT FROM AUTHOR]

Conservation efforts often use habitat models as surrogates for empirical data on the distribution or population size of target species as well as to predict the efficacy of proposed conservation and management actions. Such a model was used to evaluate preserves for the Palm Springs ground squirrel (Spermophilus tereticaudus chlorus) under a proposed Habitat Conservation Plan in the Sonoran Desert of southern California. The habitat model was developed from expert opinion and data from nonprobability-based sample surveys for ground squirrels. We evaluated the model and tested the underlying assumptions about the ground squirrel's habitat affinities, estimated the occupancy rates and detection probabilities of ground squirrels in modeled habitat, quantified the total area of the proposed preserves occupied by ground squirrels, and tested a priori hypotheses about how occupancy differed among vegetation and substrate types. Occupancy rate varied with vegetation and substrate types and, by repeatedly visiting survey points, we found that detection probability was -0.22 (SÊ = 0.05). We found ground squirrels were more likely to occupy mesquite (Prosopis glandulosa variety torreyana) on dunes/hummocks (0.99 ± 0.01) than creosote (Larrea tridentata) on dunes/hummocks (0.33 ± 0.09) or other vegetation/substrate types (⩽0.08). Our results suggest that this and comparable habitat models should be refined to incorporate detection probabilities and variation in ground squirrel affinity for different vegetation and substrates. In contrast to the existing habitat model, our data suggested that ground squirrel occupancy rate differed by vegetation/substrate types. We suggest that conservation efforts focus on protecting and enhancing the mesquite hummock/dune system that has largely disappeared over the last 50 years due to agricultural and urban development and a lowering of water tables. [ABSTRACT FROM AUTHOR]

Groundwater management in the Edwards Aquifer in Texas is in the process of moving away from a traditional right of capture economic regime toward a more environmentally sensitive scheme designed to preserve endangered species habitats. This study explores economic and environmental implications of proposed groundwater management and water development strategies under a proposed regional Habitat Conservation Plan. Results show that enhancing the habitat by augmenting water flow costs $109-1427 per acre-foot and that regional water development would be accelerated by the more extreme possibilities under the Habitat Conservation Plan. The findings also indicate that a water market would improve regional welfare and lower water development but worsen environmental attributes. [ABSTRACT FROM AUTHOR]

Extensive acreage loss of coastal sage scrub (CSS), isolation of surviving stands, and the federal listing of several animal species with obligate relationships to this plant community, particularly the threatened California gnatcatcher (Polioptila californica), have led to attempts to create CSS to mitigate habitat lost to urban development and other causes. Many of these creations lie within habitat conservation plan (HCP) sites, and they could play a more prominent role by being repositories for plants taken from a single site having site-specific genetics. Among others, one technique that increases initial resemblance to natural stands uses digitized, to-scale photography, which has been ground-truthed to verify vascular plant associations, which appear as mosaics on a landscape. A combination of placing patches of salvaged, mature canopy plants within larger matrices of imprinted or container plant plots appears to significantly enhance immediate use by CSS obligate bird species, accelerate “spread” or expansion of CSS, and can also introduce many epiphytic taxa that otherwise would be slow or unable to occupy developing CSS creations. Reptile, amphibian, butterfly, and rodent diversity in a salvaged canopy restoration case study at the University of California, Irvine, showed CSS species foraging and inhabiting transplanted canopy patches. Using restoration techniques to expand existing CSS stands has more promise than creating isolated patches, and the creation of canopies resembling CSS mid-fire cycle stands is now common. Gnatcatchers and other birds use restorations for foraging and occasional nesting, and in some cases created stands along “biological corridors” appear to be useful to bird movement. Patches of transplanted sage scrub shrubs along habitat edges appear to break up linear edge effects. There are no data on which long-term survival, succession, or postfire behavior can be predicted for CSS restoration sites, and postfire community changes are not part of either mitigation or restoration planning at present. Long-term planning including burning is needed so that a fire-adapted habitat will develop. Restoration is important in retaining genetic resources, for ameliorating edge effects, as habitat extenders in buffer zones around HCP sites, and by providing areas into which natural stands can expand. [ABSTRACT FROM AUTHOR]

The City of Austin, Texas, is one of the fastest growing metropolitan areas in the United States. It is also in one of the most biologically diverse terrestrial ecosystems in the world: the Balcones Canyonlands. Five cave invertebrates and two species of birds that inhabit the area are listed as threatened or endangered, two species of plants are candidates for listing, several others are considered rare and of concern, and a species of the salamander has also been proposed for listing. A habitat conservation plan, of 'national significance⋯' according to Secretary of Interior Bruce Babbit (Haurwitz 1996), has been under development for the last several years to conserve those endangered species through a 2400-ha system of preserves and to allow development to continue in more than 162,000 ha of surrounding area. The preserve system, comprising several units ranging in size from less than a hundred to several thousand hectares, would be bordered in many instances by developed areas. Development and maintenance of the infrastructure necessary for new and existing development, both commercial and residential, could have negated the biological value of the preserves (e.g., power-line corridors, water-treatment pipelines and facilities). The challenge of bringing this plan to fruition illustrates the complex biological, technical, and sociological context within which habitat conservation planning may occur. Resolving resource use conflicts of this nature have several commonalities that overarch these contexts. If recognized and addressed, one may move easily and foster positive results. These commonalities can be expressed as principles such as: relying on scientists to recognize, but not solve problems; acting before a scientific consensus is achieved; including human motivation and responses as part of the system to be studied and managed; and confronting uncertainty. [ABSTRACT FROM AUTHOR]