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Explore WARC's science publications.

Filter Total Items: 3509

Causal effects verses causal mechanisms: Two traditions with different requirements and contributions towards causal understanding Causal effects verses causal mechanisms: Two traditions with different requirements and contributions towards causal understanding

The scientific aspiration of building causal knowledge has received little explicit discussion in ecology despite its fundamental importance. When methods are described as ‘causal’, emphasis is increasingly placed on statistical techniques for isolating associations so as to quantify causal effects. In contrast, natural scientists have historically approached the pursuit of causal...
Authors
James Grace, Nick Huntington-Klein, E. William Schweiger, Melinda Martinez, Michael Osland, Laura C. Feher, Glenn R. Guntenspergen, Karen M. Thorne

Using DNA barcoding to evaluate freshwater mussel and fish-host relationships in the Flint River (Georgia, USA) Using DNA barcoding to evaluate freshwater mussel and fish-host relationships in the Flint River (Georgia, USA)

Freshwater mussels have a unique life history in which larval mussels (glochidia) act as obligate parasites to fish hosts. Host selectivity may be species specific, and identification of host fish is a critical step in conservation planning for individual mussel species. The Flint River harbors ~23% of the freshwater mussel (order Unionida) diversity in the state of Georgia, USA. Nine...
Authors
Hayley A. Robinson, John P. Wares, Gail M. Cowie, Shayla D. Williams, Ben F Scott, Matthew T. Rowe, Nathan Johnson, Peter D. Hazelton

Object detection-assisted workflow facilitates cryptic snake monitoring Object detection-assisted workflow facilitates cryptic snake monitoring

Camera traps are an important tool used to study rare and cryptic animals, including snakes. Time-lapse photography can be particularly useful for studying snakes that often fail to trigger a camera's infrared motion sensor due to their ectothermic nature. However, the large datasets produced by time-lapse photography require labor-intensive classification, limiting their use in large...
Authors
Storm Miller, Michael Kirkland, Kristen Hart, Robert A. McCleery

Ecological thresholds and transformations due to climate change: The role of abiotic stress Ecological thresholds and transformations due to climate change: The role of abiotic stress

An ecological threshold is the point at which a comparatively small environmental change triggers an abrupt and disproportionately large ecological response. In the face of accelerating climate change, there is concern that abrupt ecosystem transformations will become more widespread as critical ecological thresholds are crossed. There has been ongoing debate, however, regarding the...
Authors
Michael Osland, John B. Bradford, Lauren T. Toth, Matthew J. Germino, James Grace, Judith Z. Drexler, Camille L. Stagg, Eric E. Grossman, Karen M. Thorne, Stephanie Romanach, Davina Passeri, Gregory E. Noe, Jessica R. Lacy, Ken Krauss, Kurt P. Kowalski, Glenn R. Guntenspergen, Neil K. Ganju, Nicholas Enwright, Joel A. Carr, Kristin B. Byrd, Kevin J. Buffington

Insect pollinator crossing of international border barriers along the U.S.-Mexico border Insect pollinator crossing of international border barriers along the U.S.-Mexico border

Infrastructure along the U.S.-Mexico Border may not be equally permeable to all types of insect pollinators with potential implications for pollen and gene flow between plant populations. Pollinators were observed on their approach to two types of border barriers (slatted and cemented) along the U.S.-Mexico Border from March 2023 to January 2024. Near the barrier, four insect behaviors...
Authors
Beth Middleton

Identifying gaps in regulatory prevention measures for nonindigenous aquatic species in the United States Identifying gaps in regulatory prevention measures for nonindigenous aquatic species in the United States

Nonindigenous aquatic species (NAS) present in trade can become costly invaders once introduced and established in a new environment. Preventing NAS introduction is considered the most effective strategy to avoid potential negative ecological, economic, and human health impacts associated with certain species. The United States government enacts regulatory prevention measures carried out...
Authors
Zoey Hendrickson, Charles M. Martin, Wesley Daniel

A synthesis of freshwater forested wetland soil organic carbon storage A synthesis of freshwater forested wetland soil organic carbon storage

Freshwater forested wetlands account for ~76% (918 M ha) of the total global wetland extent. However, freshwater forested wetlands are difficult to distinguish from upland forest due to canopy coverage, the abundance of wetland-nonwetland mosaics, seasonal hydropatterns, and fewer readily observable connections to large surface water bodies relative to marshes and other emergent habitats
Authors
Yadav Sapkota, Jacob F. Berkowitz, Camille Stagg, Ryan R. Busby

Linking environmental variability to long-term demographic change of an endangered species using integrated population models Linking environmental variability to long-term demographic change of an endangered species using integrated population models

Understanding how species populations change with environmental conditions is important for implementing effective habitat management and conservation strategies. Challenges to evaluating population-level responses to environmental conditions arise when data are sparse or not spatiotemporally aligned, especially for at-risk species with small, declining numbers.We synthesized 30 years...
Authors
Marisa Takada Martinez, Laura D’Acunto, Stephanie Romanach

Piping Plover home ranges do not appear to be impacted by restoration of barrier islands and headlands Piping Plover home ranges do not appear to be impacted by restoration of barrier islands and headlands

Restoration of barrier island and headland habitats can alter existing and create new habitats, which may impact wildlife occupying these areas such as the threatened Piping Plover (Charadrius melodus). We used resight data from banded birds to develop minimum convex polygon (MCP) and kernel density estimates (KDE) of individual Piping Plover home ranges to investigate whether changes in...
Authors
Theodore J. Zenzal, Amanda Nicole Anderson, Delaina LeBlanc, Robert C. Dobbs, Brock Geary, Hardin Waddle

A survey of mammal and fish genetic diversity across the global protected area network A survey of mammal and fish genetic diversity across the global protected area network

Global conservation targets aim to expand protected areas and maintain species’ genetic diversity. Whether protected areas capture genetic diversity is unclear. We examined this question using a global sample of nuclear population-level microsatellite data comprising genotypes from 2513 sites, 134,183 individuals, and 176 mammal and marine fish species. The genetic diversity and...
Authors
Chloe Schmidt, Eleana Karachaliou, Amy G. Vandergast, Eric D. Crandall, Jeff T. Falgout, Margaret Hunter, Francine Kershaw, Deborah M. Leigh, David O'Brien, Ivan Paz-Vinas, Gernot Segelbacher, Colin J. Garroway

Effectiveness of stewardship and management strategies to conserve coastal bird populations in the northern Gulf of Mexico: A literature review Effectiveness of stewardship and management strategies to conserve coastal bird populations in the northern Gulf of Mexico: A literature review

Shorebirds, seabirds, and wading birds (hereafter coastal birds) have experienced considerable losses over the last century and require proactive conservation management to stabilize or grow populations. Habitat loss and/or degradation and human disturbance are among the most urgent threats faced by coastal bird populations. Identifying effective conservation management techniques to...
Authors
Jennifer L. Fuller, Nicole L. Michel, Evan M. Adams, Abigail J. Darrah, Auriel Fournier, Jacquelyn K. Grace, Lianne Koczur, Bethany A.C. Kraft, Terri J. Maness, Sarah P. Saunders, Caz M. Taylor, Kiara L. Valentine, Theodore J. Zenzal

Flow cytometric detection of waterborne bacteria metabolic response to anthropogenic chemical inputs to aquatic ecosystems Flow cytometric detection of waterborne bacteria metabolic response to anthropogenic chemical inputs to aquatic ecosystems

Typical investigations into the biological consequences of suspected xenobiotics or nutrients introduced in watersheds include analytical chemistry screens of environmental samples—such as periphyton responses or studies of fish condition—which are all costly in terms of equipment, reagents, time, and human resources. An alternative is to assess pollutant effects on waterborne bacteria...
Authors
Jill Jenkins, Scott Mize, Darren Johnson, Bonnie L. Brown
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