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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. Disturbance can have profound effects on biota. Using minnow traps, acoustic, and visual surveys, we demonstrate evidence of habitat‐partitioning between the federally endangered Fowler's toad and other frog taxa, in accordance with the natural disturbance regime, not anthropogenic disturbance, affecting the landscape. We advocate that management should prioritize the maintenance of the natural disturbance regime to best conserve all anuran species in the area.

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.

Waterfowl management is more effective when based on detailed information on population connectivity between breeding, wintering, and stopover sites. For the American black duck (Anas rubripes), a species of conservation concern, estimates for the fall age ratio at harvest differed depending on whether harvest data were derived from Canada or the United States, suggesting regional differences. Within Canada, hunters in Atlantic Canada were more likely to harvest black ducks from nearby breeding locations compared to hunters in southern Ontario and Quebec, Canada, who were more likely to harvest individuals from the Boreal Softwood and Taiga Shield of eastern Canada. Black ducks harvested in the United States are thought to originate predominantly from northern portions of the breeding range, leading to the flyover hypothesis, which postulates that black ducks produced in the Boreal Softwood and Taiga Shield region are less susceptible to harvest by hunters in Atlantic Canada and northeastern United States. To test the flyover hypothesis, we examined regional and temporal differences in the origins of harvested black ducks using feathers from wings (n= 664) submitted by hunters to the species composition and parts collection surveys across 3 hunting seasons (2017–2018, 2018–2019, 2019–2020). We used a likelihood‐based assignment method that relied on feather stable‐hydrogen isotopes (δ2H) and stable‐carbon isotopes (δ13C) to determine the natal or molt origin of individuals harvested within eastern Canada and the United States. We also used a spatial clustering technique to group harvested individuals by area of origin without a prioriknowledge of such regions. Adult female black ducks originated farther south compared to males and juveniles. All sexes and ages of black ducks harvested in Atlantic Canada showed predominantly southern origins, while those harvested in the United States and other Canadian provinces primarily originated farther north within the boreal, supporting the flyover hypothesis. By contrast, we found no relationship between timing of harvest or peaks of migration and individual origin. After combining band returns and stable isotopes, we inferred 2 distinct stocks: the Mississippi flyway stock and the Atlantic flyway stock. We recommend that regional demographic parameters, particularly for Atlantic Canada, be directly measured to promote more effective conservation of black ducks and optimize harvest opportunities in the United States and Canada. The flyover hypothesis proposes that American black ducks harvested in Atlantic Canada originate from nearby breeding locations, in the south, while those harvested in the USA and elsewhere in Canada are thought to originate from farther north in the boreal. We examined regional differences in the origins of harvested ducks using stable isotopes within feathers and found that ducks harvested in Atlantic Canada showed predominantly southern origins, while those harvested elsewhere primarily originated farther north.

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.

We tested the equal preference ecological trap hypothesis for breeding yellow-bellied sapsuckers (Sphyrapicus varius) along a time-since-harvest gradient (1–5?yr, 16–20?yr, 21–25?yr, and >60?yr) in selection system-logged hardwood forests in Algonquin Provincial Park, Ontario. Yellow-bellied sapsuckers preferred 1–5 year and >60-year-old cuts equally and more than 16–20 year and 21–25-year-old cuts. More-abundant arthropod food and/or higher-quality sap resources may have attracted yellow-bellied sapsuckers to 1–5 year and >60-year-old cuts. Only 52% of pairs raised fledglings in 1- to 5-year-old cuts during years when nest predation by American black bears (Ursus americanus) was common, the incidence of which was negatively related to increased availability of American beech (Fagus grandifolia) nuts from the previous autumn. By contrast, 88% of pairs raised fledglings in all years in >60-year-old cuts. One- to 5-year-old cuts were demographic sinks that represent equal-preference ecological traps in years when nest predation by bears was common, whereas >60-year-old cuts were always demographic sources. High-quality habitat cues for nesting yellow-bellied sapsuckers appear to be retained for 1–5 years after selection system logging but fail to deliver safe nest sites. Cavities excavated in heart-rot-infected nest trees are least likely to be depredated because cavity walls are typically harder and deter entry by depredating bears. Retaining more potential nest trees per ha at harvest (especially American beech with heart-rot) may increase the proportion of sapsucker nests that are excavated in bear-resistant trees, thereby reducing nest predation and increasing fecundity. © 2012 The Wildlife Society.