Robert F. Baldwin

Conservation Planning for Amphibian Species with Complex Habitat Requirements: A Case Study Using Movements and Habitat Selection of the Wood Frog Rana sylvatica

Abstract Conservation of fauna breeding in vernal pools is challenging given their complex life histories. Many species, including the widespread North American Wood Frog (Rana sylvatica), require both aquatic and terrestrial habitat, yet insufficient information exists about movements between these environments, nor fine-scale selection patterns within them. To inform conservation planning, we conducted a radio-telemetry study of seasonal patterns of Wood Frog movements and habitat selection in southern Maine. Forty-three frogs were tracked an average of 25.6 days each, April to November 2003. In early spring, Wood Frogs generally selected damp leaf litter retreats on the margins of breeding pools. Following breeding, frogs selected forested wetlands (9.3% of the landscape) over forested uplands (90.7% of the landscape) in 75.3% of radio locations (N  =  544). Postbreeding movements from breeding pools to nearby, closed-canopy, forested wetlands ranged from 102–340 m (median 169m, N  =  8) and included stopovers in upland forest floors ranging from one to 17 days (median two days, N  =  7). Summer refugia were characterized by shady, moist (nonaquatic), and sphagnum-dominated microhabitats. In urbanizing areas, we recommend a shift from a core-habitat conservation model to a spatially explicit approach that considers pool-breeding amphibian habitat as a network of migration-connected habitat elements (e.g., breeding pools, upland forest, nearby forested wetlands). In our study, this approach reduced the amount of land potentially requiring protection by > 2/3 from that of core habitat models. With the rapid dissemination of GIS technology, spatially explicit planning for pool-breeding amphibians is increasingly feasible.

Bolder Thinking for Conservation

SHOULD CONSERVATION TARGETS, such as the proportion of a region to be placed in protected areas, be socially acceptable from the start? Or should they be based unapologetically on the best available science and expert opinion, then address issues of practicality later? Such questions strike to the philosophical core of conservation. Ambitious targets are often considered radical and value laden, whereas modest targets are ostensibly more objective and reasonable. The personal values of experts are impossible to escape in either case. Conservation professionals of a biocentric bent might indeed err on the side of protecting too much. Anthropocentric bias, however, more commonly affects target setting. The pro-growth norms of global society foster timidity among conservation professionals, steering them toward conformity with the global economic agenda and away from acknowledging what is ultimately needed to sustain life on Earth.

Toward Best Practices for Developing Regional Connectivity Maps

To conserve ecological connectivity (the ability to support animal movement, gene flow, range shifts, and other ecological and evolutionary processes that require large areas), conservation professionals need coarse-grained maps to serve as decision-support tools or vision statements and fine-grained maps to prescribe site-specific interventions. To date, research has focused primarily on fine-grained maps (linkage designs) covering small areas. In contrast, we devised 7 steps to coarsely map dozens to hundreds of linkages over a large area, such as a nation, province, or ecoregion. We provide recommendations on how to perform each step on the basis of our experiences with 6 projects: California Missing Linkages (2001), Arizona Wildlife Linkage Assessment (2006), California Essential Habitat Connectivity (2010), Two Countries, One Forest (northeastern United States and southeastern Canada) (2010), Washington State Connected Landscapes (2010), and the Bhutan Biological Corridor Complex (2010). The 2 most difficult steps are mapping natural landscape blocks (areas whose conservation value derives from the species and ecological processes within them) and determining which pairs of blocks can feasibly be connected in a way that promotes conservation. Decision rules for mapping natural landscape blocks and determining which pairs of blocks to connect must reflect not only technical criteria, but also the values and priorities of stakeholders. We recommend blocks be mapped on the basis of a combination of naturalness, protection status, linear barriers, and habitat quality for selected species. We describe manual and automated procedures to identify currently functioning or restorable linkages. Once pairs of blocks have been identified, linkage polygons can be mapped by least-cost modeling, other approaches from graph theory, or individual-based movement models. The approaches we outline make assumptions explicit, have outputs that can be improved as underlying data are improved, and help implementers focus strictly on ecological connectivity.

Clarifying the role of fire in the deciduous forests of eastern North America: reply to Matlack

Fire is an important disturbance in ecosystems across the eastern deciduous forests of North America (Brose et al. 2014). Matlack (2013) provided an interpretation of historical and contemporary fire in this region. Although we applaud Matlack for correcting simplistic assumptions that fire was ubiquitous and all plant communities need to burn regularly to maintain biodiversity, we believe his interpretation of the role of fire is erroneous on several counts. Most problematic is his statement “ . . . it seems prudent to limit the use of prescribed burning east of the prairie-woodland transition zone.” Adherence to this overgeneralized advice would inevitably result in losses of native diversity across the eastern deciduous forest.

The World's Most Isolated and Distinct Whale Population? Humpback Whales of the Arabian Sea

A clear understanding of population structure is essential for assessing conservation status and implementing management strategies. A small, non-migratory population of humpback whales in the Arabian Sea is classified as “Endangered” on the IUCN Red List of Threatened Species, an assessment constrained by a lack of data, including limited understanding of its relationship to other populations. We analysed 11 microsatellite markers and mitochondrial DNA sequences extracted from 67 Arabian Sea humpback whale tissue samples and compared them to equivalent datasets from the Southern Hemisphere and North Pacific. Results show that the Arabian Sea population is highly distinct; estimates of gene flow and divergence times suggest a Southern Indian Ocean origin but indicate that it has been isolated for approximately 70,000 years, remarkable for a species that is typically highly migratory. Genetic diversity values are significantly lower than those obtained for Southern Hemisphere populations and signatures of ancient and recent genetic bottlenecks were identified. Our findings suggest this is the worlds most isolated humpback whale population, which, when combined with low population abundance estimates and anthropogenic threats, raises concern for its survival. We recommend an amendment of the status of the population to “Critically Endangered” on the IUCN Red List.

Importance of Riparian Forest Buffers in Conservation of Stream Biodiversity: Responses to Land Uses by Stream-Associated Salamanders across Two Southeastern Temperate Ecoregions

Abstract Stream microhabitats are strongly influenced by adjacent terrestrial land use and other anthropogenic disturbances. Therefore, sensitive stream fauna can be highly imperiled. We investigated relative susceptibility of stream-associated salamanders to riparian land use by studying species-specific responses that influence community assembly. The Piedmont and Blue Ridge ecoregions of the southeastern United States have high aquatic biodiversity, centuries of land use, and increasingly extensive urbanization. We surveyed low-order streams in these regions for salamanders across four riparian land uses (forests, agricultural, residential, and urban) and assessed 15 habitat variables at each sampling site. We found that forested streams were more diverse compared to streams affected by riparian land uses. Our study showed two distinct assemblages of salamanders in response to riparian land use: forest-dependent, large-bodied, long-lived species sensitive to riparian land uses (disturbance avoiders) and cosmopolitan, small-bodied, short-lived species that are relatively resistant to impacts of riparian land uses (disturbance tolerants). These assemblages varied in composition between the ecoregions, with Blue Ridge harboring more land-use–intolerant species. Results indicated that multiple habitat features of the riparian zone (canopy cover, canopy height, leaf litter cover), and stream geomorphology (bank complexity, streambed heterogeneity, sedimentation) are dramatically altered by riparian land uses, and influence the assemblage structure of salamanders. Riparian buffers in both ecoregions are largely unprotected (70% in Blue Ridge, 96% in Piedmont) and are possibly threatened with anthropocentric land uses. Results suggested that conservation of stream salamander communities should be strengthened with protection and restoration of riparian forests, connectivity among riparian forests, and soil-conservation practices.

Water quality of small seasonal wetlands in the Piedmont ecoregion, South Carolina, USA: Effects of land use and hydrological connectivity.

Small, shallow, seasonal wetlands with short hydroperiod (2-4 months) play an important role in the entrapment of organic matter and nutrients and, due to their wide distribution, in determining the water quality of watersheds. In order to explain the temporal, spatial and compositional variation of water quality of seasonal wetlands, we collected water quality data from forty seasonal wetlands in the lower Blue Ridge and upper Piedmont ecoregions of South Carolina, USA during the wet season of February to April 2011. Results indicated that the surficial hydrological connectivity and surrounding land-use were two key factors controlling variation in dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) in these seasonal wetlands. In the sites without obvious land use changes (average developed area <0.1%), the DOC (p < 0.001, t-test) and TDN (p < 0.05, t-test) of isolated wetlands were significantly higher than that of connected wetlands. However, this phenomenon can be reversed as a result of land use changes. The connected wetlands in more urbanized areas (average developed area = 12.3%) showed higher concentrations of dissolved organic matter (DOM) (DOC: 11.76 ± 6.09 mg L(-1), TDN: 0.74 ± 0.22 mg L(-1), mean ± standard error) compared to those in isolated wetlands (DOC: 7.20 ± 0.62 mg L(-1), TDN: 0.20 ± 0.08 mg L(-1)). The optical parameters derived from UV and fluorescence also confirmed significant portions of protein-like fractions likely originating from land use changes such as wastewater treatment and livestock pastures. The average of C/N molar ratios of all the wetlands decreased from 77.82 ± 6.72 (mean ± standard error) in February to 15.14 ± 1.58 in April, indicating that the decomposition of organic matter increased with the temperature. Results of this study demonstrate that the water quality of small, seasonal wetlands has a direct and close association with the surrounding environment.

Introduction: Creating a Context for Landscape-Scale Conservation Planning

Over the last 130 years, conservation practitioners have increasingly enlarged their view of the important spatial scales on which to base the development and implementation of conservation plans. For example, even though national parks have been an essential tool in the global conservation toolbox since the late 1800s, it is now well understood that critical conservation goals can only be achieved if parks are viewed as being connected to each other ecologically and embedded within a larger landscape that includes a diverse mixture of ownerships, histories, and uses. The tools for planning at these greater spatial scales, from both the natural and social sciences, are only slowly being developed, tested, and refined. This book represents a step in that process, bringing together lessons on a variety of perspectives – including history, economics, wildlife biology, computer modeling, and climate change science – on how to achieve landscape-scale conservation planning. Although the authors represented in this book primarily describe their work on conservation planning in Eastern North America, these chapters serve as case studies on how conservation planning can be successfully approached in landscapes anywhere in the world.

Connectivity Restoration in Large Landscapes: Modeling Landscape Condition and Ecological Flows

©2012 by the Board of Regents of the University of Wisconsin System. Connectivity Restoration in Large Landscapes: Modeling Landscape Condition and Ecological Flows Robert F. Baldwin (school of Forest, agricultural and Environmental sciences, clemson University, baldwi6@clemson .edu), sarah E. Reed (north america Program, Wildlife conservation society, sarah.Reed@colostate.edu), Brad H. McRae (The nature conservancy, seattle, Wa, bmcrae@ tnc.org), David M. Theobald (Department of Fish, Wildlife, and conservation Biology, colorado state University, David.Theobald@colostate.edu), and Ronald W. sutherland (Wildlands network, ron@wildlandsnetwork.org)

gflow: software for modelling circuit theory‐based connectivity at any scale

Summary Increasing habitat connectivity is important for mitigating the effects of climate change, landscape fragmentation and habitat loss for biodiversity conservation. However, modelling connectivity at the relevant scales over which these threats occur has been limited by computational requirements. Here, we introduce the open-source software gflow, which massively parallelizes the computation of circuit theory-based connectivity. The software is developed for high-performance computing, but scales to consumer-grade desktop computers running modern Linux or Mac OS X operating systems. We report high computational efficiency representing a 173× speedup over existing software using high-performance computing and a 8·4× speedup using a desktop computer while drastically reducing memory requirements. gflow allows large-extent and high-resolution connectivity problems to be calculated over many iterations and at multiple scales. We envision gflow being immediately useful for large-landscape efforts, including climate-driven animal range shifts, multitaxa connectivity, and for the many developing use-cases of circuit theory-based connectivity.