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Wetlands conserved using water level manipulation, cattle exclusion, naturalization of uplands, and other techniques under the North American Waterfowl Management Plan ("conservation project wetlands") are important for ducks, geese, and swans ("waterfowl"). However, the assumption that conservation actions for waterfowl also benefit other wildlife is rarely quantified. We modeled detection and occupancy of species at sites within 42 conservation project wetlands compared to sites within 52 similar nearby unmanaged wetlands throughout southern Ontario, Canada, and small portions of the adjacent U.S., using citizen science data collected by Bird Studies Canada's Great Lakes Marsh Monitoring Program, including 2 waterfowl and 13 non-waterfowl marsh-breeding bird species (n = 413 sites) and 7 marsh-breeding frog species (n = 191 sites). Occupancy was significantly greater at conservation project sites compared to unmanaged sites in 7 of 15 (47%) bird species and 3 of 7 (43%) frog species, with occupancy being higher by a difference of 0.12-0.38 across species. Notably, occupancy of priority conservation concern or at-risk Black Tern (Chlidonias niger), Common Gallinule (Gallinula galeata), Least Bittern (Ixobrychus exilis), Sora (Porzana carolina), and Western Chorus Frog (Pseudacris triseriata) was significantly higher at conservation project sites compared to unmanaged sites. The results demonstrate the utility of citizen science to inform wetland conservation, and suggest that actions under the North American Waterfowl Management Plan are effective for conserving non-waterfowl species., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The maintenance of biological diversity is frequently enhanced in a heterogenous landscape by some level of disturbance. Thus, when a landscape becomes stabilized and homogenized through the spread of an invasive plant species, there may be consequences for native biodiversity, particularly for those biotas that depend on the pre‐existing, natural disturbance regime of that landscape. At Long Point, Ontario, Canada, a sandspit in Lake Erie, the community of anuran amphibians experienced the co‐incidence of 2 major disturbance events, 1 anthropogenic and 1 natural: an intervention to remove the invasive form of the common reed (Phragmites australis australis) and a spate of extensive dune washouts caused by high water levels and storms. As a result of the unequal distribution of disturbance in the landscape, different areas were affected by only the dune washouts, only the common reed treatment, both disturbances, or neither disturbance. From May to August 2021, we explored how the disturbances affected the resident frog and toad species habitat associations in the 4 different disturbance conditions in the landscape. By means of minnow traps, acoustic surveys, and visual surveys, we determined that the dune washouts had a greater influence on resident anurans than the common reed treatment. Ranid frogs (Ranidae) tended to inhabit non‐washout sites, whereas Fowler's toads (Anaxyrus fowleri) congregated in the newly formed, sand flats and shallow, de‐vegetated pools resulting from the washouts. Neither ranid frogs nor Fowler's toads demonstrated avoidance of the sites affected by the herbicide treatment and mechanical rollover of the common reed. This evidence of species sorting, which enables multiple species to persist in a dynamic and heterogeneous landscape, suggests that wildlife management in aid of threatened species recovery may find success by encouraging natural disturbance regimes in dynamic landscapes. Future management endeavors should consider refraining from complete dune stabilization in these landscapes to allow the natural washouts to occur at a higher frequency, while ensuring the continued effectiveness of the invasive common reed eradication. [ABSTRACT FROM AUTHOR]

Species often exhibit regionally specific habitat associations, so habitat association models developed in one region might not be accurate or even appropriate for other regions. Three programs to survey wetland‐breeding birds covering (respectively) Great Lakes coastal wetlands, inland Great Lakes wetlands, and the Prairie Pothole Region offer an opportunity to test whether regionally specific models of habitat use by wetland‐obligate breeding birds are transferrable across regions. We first developed independent, regional population density models for four species of wetland‐obligate birds: Pied‐billed Grebe (Podilymbus podiceps), Virginia Rail (Rallus limicola), Sora (Porzana carolina), and American Bittern (Botaurus lentiginosus). We then used adjusted pseudo‐R2 values to compare the amount of variation explained by each model when applied to data collected in each of the three regions. Although certain habitat characteristics, such as emergent vegetation and wetland area, were consistently important across regions, models for each species differed by region—both in variables selected for inclusion and often in the directionality of relationships for common variables—indicating that habitat associations for these species are regionally specific. When we applied a model developed in one region to data collected in another region, we found that explanatory power was reduced in most (71%) models. Therefore, we suggest that ecological analyses should emphasize regionally specific habitat association models whenever possible. Nonetheless, models created from inland Great Lakes wetland data had higher median explanatory power when applied to other regions, and the amount of explanatory power lost by other transferred models was relatively small. Thus, while regionally specific habitat association models are preferable, in the absence of reliable regional data, habitat association models developed in one region may be applied to another region, but the results need to be cautiously interpreted. Additionally, we found that median explanatory power was higher when local‐scale habitat characteristics were included in the models, indicating that regionally specific models should ideally be based on a combination of local‐ and landscape‐scale habitat characteristics. Conservation practitioners can leverage such regionally specific models and associated monitoring data to help prioritize areas for management activities that contribute to regional conservation efforts. [ABSTRACT FROM AUTHOR]

Water-level regulation can have significant impacts on coastal wetland ecosystems. In this study we sought to update marsh-bird-based ecological performance indicators (PIs) that support adaptive management of long-term outflow regulation for Lake Ontario. Previous PIs established in the mid-2000 s were based on single species and monitoring them required data not currently being collected at broad scales. We therefore focused on developing and validating community-level PIs using data from an ongoing, long-term, basin-wide monitoring program, the Coastal Wetland Monitoring Program (CWMP). After identifying species with documented responses to variation in water levels in the literature, we considered a suite of potential PIs by first examining correlations with both annual mean water levels and measures of interannual water-level fluctuations. We then used a mixed-modelling framework to determine which highly correlated PIs exhibited statistically significant relationships with water-level variables. Having established significant effects of water levels on the candidate PIs, we performed a power-sensitivity analysis to determine the degree of change in each PI that can be detected based on current CWMP sampling. From these analyses, we propose six potential marsh-bird based PIs: sum total abundance of sensitive marsh-obligate species, richness of sensitive marsh-obligate species, and abundance of each of red-winged blackbird (Agelaius phoeniceus), marsh wren (Cistothorus palustris), common gallinule (Gallinula galeata), and least bittern (Ixobrychus exilis). Of these, the community-based PIs of sum total abundance and richness of sensitive species appear most suitable for assessing the marsh-bird community response to outflow regulation on Lake Ontario. [ABSTRACT FROM AUTHOR]

Active water management of wetlands promotes seed and tuber production to feed migrating waterfowl, but few assessments exist to determine how management actions influence wetland structure, vegetation and bird response throughout the year. We identified effects of full water drawdown, partial water drawdown and passive wetlands (no active dewatering during the growing season) on plant communities and bird abundance in wetlands of the Montezuma Wetlands Complex, New York, May–October 2016–2018 and February–April 2017–2019. We detected few differences in the plant community during June, but during September we detected greater vegetative forage quality index for waterfowl, annual plant cover and seed density in full and partial drawdowns than passive wetlands. Bird abundance was greater in June–July in passive wetlands and greater in September–October in full drawdowns. During spring migration, duck densities were greater in full and partial drawdowns. Our results indicate that wetland managers should use a mix of full drawdowns and passive wetlands to provide habitat for the greatest diversity and number of birds throughout the year. [ABSTRACT FROM AUTHOR]

Populations of marsh‐breeding birds have declined throughout the southern Laurentian Great Lakes basin. To advance conservation of these species, we used occupancy modeling, a regional prioritization scheme, and data from Birds Canada's Great Lakes Marsh Monitoring Program (2016–2018) to describe species‐habitat relationships and identify priority habitat areas for 7 obligate marsh‐breeding bird species in southern Ontario, Canada: American bittern (Botaurus lentiginosus), common gallinule (Gallinula galeata), least bittern (Ixobrychus exilis), marsh wren (Cistothorus palustris), pied‐billed grebe (Podilymbus podiceps), sora (Porzana carolina), and Virginia rail (Rallus limicola). Given these species respond to land cover at widely varying spatial scales, we initially identified the most informative scale (buffer = 100 m, 200 m, 400 m, 800 m, 1,600 m, 3,200 m, or 6,400 m) for marsh, urban, agricultural, and forest cover to increase model performance. We also considered climate variables, whether sample sites were along a Great Lakes coastline or inland, and covariates influencing detection. Occupancy was best explained by land cover at a wide range of spatial scales depending on the species. All species except Virginia rail responded positively to marsh cover; American bittern and Virginia rail responded negatively to urban cover; least bittern, pied‐billed grebe, and Virginia rail responded negatively and sora responded positively to agricultural cover; and American bittern, common gallinule, marsh wren, and pied‐billed grebe responded negatively and Virginia rail responded positively to forest cover. Only American bittern responded negatively to mean May–June temperature; only pied‐billed grebe responded positively to start of growing season; and only Virginia rail had higher occupancy at inland marshes compared to coastal. We combined predictions from the best model for each of 5 species with reasonably good model fit (we excluded sora and Virginia rail) to identify priority habitat areas for marsh‐breeding birds. Expansion of wetland conservation work from existing priority areas based on waterfowl to also include these new additional priority areas based on marsh‐breeding birds will be an important step towards conservation of all birds, and will help slow or maybe even reverse declining population trends. Some restoration activities outside but adjacent to priority areas will also be important for rebuilding marshes for these species across this intensively farmed and developed region. © 2020 The Wildlife Society. We used occupancy modeling, a regional prioritization scheme, and data from Birds Canada's Great Lakes Marsh Monitoring Program to describe species‐habitat relationships and identify priority habitat areas for obligate marsh‐breeding bird species in southern Ontario, Canada. Expansion of wetland conservation work from existing priority areas based on waterfowl to also include these new additional priority areas based on marsh‐breeding birds will be an important step towards conservation of all birds in this intensively farmed and developed region. [ABSTRACT FROM AUTHOR]

• A simple biotic indicator framework for assessing the ecological condition of points or sites. • Weights for species/taxa are based on sensitivity to an explicit environmental gradient. • Example illustrated for birds of coastal wetlands in North America's Great Lakes. • The Index of Biotic Condition (IBC) framework is applicable to other taxa and ecosystems. To survive in an area, plant and animal species must confront many interacting environmental stressors at different spatial and temporal scales. Consequently, assemblages of resident species, which have successfully negotiated these stressors, are widely recognized as indicators of environmental quality. Many biotic variables have been employed as indicator metrics, but the simplest is presence/absence of sensitive species in a standardized field sample. We describe a multi-species ecological indicator, the Index of Biotic Condition (IBC), which overcomes key concerns with using indicator species or species assemblages to assess environmental quality. Developing an IBC requires substantial ecological knowledge and preliminary data to identify an appropriate set of species or species groups for the area and habitat(s) of interest and to quantify the sensitivity of these species to an explicit environmental reference gradient. Based on objective biotic response (BR) functions describing the relationship between species occurrences and the environmental gradient, we outline a method for deriving species weights (factors that determine the relative contributions of species / species groups), subsequently used to calculate the simple multispecies index. The IBC is more rigorous than structurally similar metrics like the Floristic Quality Index (FQI) and average Coefficient of Conservatism ( C ¯ ) and, at least for some applications, is more parsimonious than comprehensive metrics like the Index of Biotic Integrity (IBI) and our previously described Index of Ecological Condition (IEC). We apply information from standardized basin-wide bird surveys conducted between 2011 and 2022 (particularly a subset of data from 2011 to 2015) to develop an IBC for comparing and interpreting the environmental quality of 794 wetlands in the coastal zone of North America's Laurentian Great Lakes. Implicit in this formulation is the existence of a high-quality reference assemblage that includes 14 obligate or facultative bird species/species groups characteristic of these wetlands. The index ranges from 0 (worst condition) to 10 (best condition) and is correlated with species richness (r = 0.87), although the IBC provides additional information reflecting the taxon-specific environmental sensitivities. The distribution of IBC values for 4,359 point samples in Great Lakes coastal wetlands between 2011 and 2022 is strongly skewed right, with a median value of 2.31. Only 28 wetland points (<1%) yielded an IBC value of 8.0 or greater, suggesting that relatively complete coastal wetland bird assemblages rarely occur at specific points in today's Great Lakes coastal wetlands, consistent with the region's well-documented historical reduction in biological diversity. [ABSTRACT FROM AUTHOR]