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Adam A. Ahlers

Publications and source records attributed to Adam A. Ahlers.

2 recordsLinked to original sources

Landscape composition and proximity to water affect American badger occupancy in shortgrass prairies

Land use change in prairie ecosystems is pervasive. Prairie obligate species may be affected by these changes, though many carnivore-specific examples are unknown. We used 3 years (2018–2020) of camera-trap ( n = 381) data from Kansas, USA, to assess multiscale effects of landscape composition on habitat use by American badgers (badger, Taxidea taxus ). We predicted that site occupancy and colonization would be positively associated with the amount of prairie surrounding sites. We also predicted that site occupancy and colonization would be negatively related to amounts of agriculture and the number of wind towers surrounding sites. Badgers were insensitive to amounts of prairie surrounding sites and likely to occupy and colonize sites surrounded by row-crop agriculture. Badgers were also less likely to occupy sites farther from permanent water. Badgers may be exploiting agricultural areas because of increased prey densities or suitable burrowing substrates. Moreover, our study highlights the importance of water resources to badgers in arid regions.

Kansas

Demographic effects of a megafire on a declining prairie grouse in the mixed-grass prairie

Recent studies have documented benefits of small, prescribed fire and wildfire for grassland-dependent wildlife, such as lesser prairie-chickens ( Tympanuchus pallidicintus ), but wildlife demographic response to the scale and intensity of megafire (wildfire >40,000 ha) in modern, fragmented grasslands remains unknown. Limited available grassland habitat makes it imperative to understand if increasing frequency of megafires could further reduce already declining lesser prairie-chicken populations, or if historical evolutionary interactions with fire make lesser prairie-chickens resilient. To evaluate lesser prairie-chicken demographic response to megafires, we compared lek counts, nest density, and survival rates of adults, nests, and chicks before (2014–2016) and after (2018–2020) a 2017 megafire in the mixed-grass prairie of Kansas, USA (Starbuck fire ~254,000 ha). There was a 67% decline in attending males on leks post-fire and a 57% decline in occupied leks post-fire. Despite population declines as indicated by lek counts, adult female breeding season survival ( Ŝ ) was similar pre- ( Ŝ = 0.65 ± 0.08 [SE]) and post-fire (0.61 ± 0.08), as was chick survival (pre-fire: 0.23 ± 0.07; post-fire: 0.27 ± 0.11). Nest survival appeared lower post-fire (pre-fire: 0.38 ± 0.06; post-fire: 0.20 ± 0.06), but did not differ at the 95% confidence interval. Nest density of marked females declined 73% in areas burned by megafire. Although lesser prairie-chickens persisted in the study area and we documented minimal effects on most demographic rates, reduced lesser prairie-chicken abundance and reproductive output suggests full recovery may take >3 years. Increased propensity for megafire resulting from suppression of smaller fires, compounded by climate change and woody encroachment, may impose a short-term (3–5 year) threat to already declining lesser prairie-chicken populations.

Kansas, Oklahoma