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Species around the world are facing an unprecedented threat of extinction from a variety of stressors. Habitat loss has been identified as the single greatest threat to species at risk, coupled with pollution, over-exploitation, disease, invasive species and climate change. 1 Nearly one quarter of the world's mammals, one-third of the world's amphibian species and one in eight birds are considered globally threatened or extinct. 2 In Ontario, 215 species or species populations are listed under the Endangered Species Act, 2007 (ESA) as endangered, threatened, special concern or extirpated, and the province has many more imperiled species that have not had the benefit of being assessed and listed under the Act. 3 This dramatic decline in biodiversity not only threatens the functioning of the ecosystems that we depend on for our air, water and food, but it also reduces the resilience of these ecosystems to environmental change. Protecting at-risk species is not just a matter of conserving biodiversity, it is also about preserving the important personal connections that Ontarians have to our natural heritage, including the snapping turtles, monarch butterflies, bald eagles and woodland caribou that are part of our collective ecological community. The challenges we face in protecting and recovering species at risk are not insurmountable, but immediate, effective and sustained action is required.

Agricultural expansion and intensification are some of the leading drivers of biodiversity loss globally. Effective conservation and management strategies for threatened species in agroecosystems require information on how these species are affected by (1) the amount and configuration of natural habitats, and (2) the type and extent of agricultural land covers. The Eastern Whippoor-will (Caprimulgus vociferous) and Common Nighthawk (Chordeiles minor) are two nocturnal aerial insectivores in decline in North America, and have breeding ranges that include agriculturally dominated landscapes. We first assessed mean breeding occupancy of both species in eastern Ontario, Canada in 2016 using acoustic recording units at 127 sites. We then assessed the effects of landscape composition (forest, agriculture, wetlands, and urban covers), forest configuration (mean patch size, number of patches, distance to nearest patch), and agriculture type (perennial forages versus cropland) on Eastern Whip-poor-will occupancy. Eastern Whip-poorwill and Common Nighthawk occupancy in the study area averaged 0.244 and 0.064, respectively. We were unable to examine the relationships between landscape composition/configuration and Common Nighthawk occupancy because of small sample sizes. Nonetheless, Eastern Whip-poor-will occupancy was positively correlated with the amount of wetland cover and forest patch size, was weakly negatively correlated with urban land cover, and was unrelated to the type of agriculture. Our results highlight how the conservation of the Eastern Whip-poor-will in agricultural landscapes of eastern Canada would benefit from both wetland protection and the presence of larger forest patches, which can be accomplished through both forest protection and by allowing forest regeneration on abandoned lands.Les effets de la composition et de la configuration du paysage sur la présence de l'Engoulevent boispourri (Caprimulgus vociferous) et de l'Engoulevent d'Amérique (Chordeiles minor) dans un agroécosystème RÉSUMÉ. L'expansion et l'intensification de l'agriculture sont parmi les causes principales de perte de biodiversité à l'échelle mondiale. Pour que les stratégies de conservation et de gestion des espèces menacées vivant dans les agroécosystèmes soient efficaces, il est important de savoir comment ces espèces sont affectées par (1) la superficie et la configuration des milieux naturels, et (2) le type et l'étendue des terres agricoles. L'Engoulevent bois-pourri (Caprimulgus vociferous) et l'Engoulevent d'Amérique (Chordeiles minor) sont deux insectivores aériens nocturnes en diminution en Amérique du Nord, et leur aire de nidification comprend des paysages dominés par l'agriculture. Premièrement, nous avons déterminé la présence de ces deux espèces au moment de la nidification dans l'est de l'Ontario, Canada, à l'aide d'enregistreurs automatiques à 127 sites en 2016. Nous avons ensuite évalué les effets de la composition du paysage (couvert forestier, agricole, de milieux humides ou urbain), de la configuration forestièr...