Browsing by Author "Durant, Sarah M."

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    A dead giveaway: foraging vultures and other avian scavengers respond to auditory cues
    (John Wiley & Sons, 2020) Jackson, Craig R.; Maddox, Thomas; Mbise, Franco P.; Stokke, Bård G.; Belant, Jerrold L.; Bevanger, Kjetil; Durant, Sarah M.; Fyumagwa, Robert; Ranke, Peter S.; Røskaft, Eivin; May, Roel; Fossøy, Frode
    Carrion represents an unpredictable and widely distributed primary food source for vultures and other avian scavengers. Avian scavengers in African savanna ecosystems are reported to rely exclusively on visual stimuli to locate carcasses. However, carnivores’ predation of large mammalian herbivores and subsequent competition for access to the carcass can result in considerable noise, often audible over long distances and for prolonged periods. Vultures and other avian scavengers may therefore detect and respond to these auditory cues, as do the mammalian carnivores alongside which vultures have coevolved, but this has not been investigated to date. Working in the Serengeti ecosystem, Tanzania, we used diurnal auditory broadcasts to simulate predation and competitive carnivore feeding interactions. Based on the current understanding of avian scavenger ecology, we hypothesized that avian responses to call‐in stations would be evoked exclusively by visual, rather than auditory, cues. We therefore predicted that (a) the arrival of avian scavengers at call‐in stations should be preceded and facilitated by mammalian carnivores and that (b) the arrival of avian scavengers would be positively correlated with the number of mammalian scavengers present, which would increase detectability. We recorded 482 birds during 122 separate playback events. In 22% of these instances, avian scavengers arrived first, ruling out responses based exclusively on visual observations of mammalian carnivores, thereby contradicting our first prediction. Furthermore, the first avian arrivals at survey sessions were inversely related to the number of hyenas and jackals present, contradicting our second prediction. Since no bait or carcasses were used during the experiments, these responses are indicative of the birds’ ability to detect and respond to audio stimuli. Our findings challenge the current consensus of sensory perception and foraging in these species and provide evidence that avian scavengers have the ability to use sound to locate food resources.
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    Developing fencing policies for dryland ecosystems
    (British Ecological Society, 2015) Durant, Sarah M.; Becker, Matthew S.; Creel, Scott; Bashir, Sultana; Dickman, Amy J.; Beudels-Jamar, Roseline C.; Lichtenfeld, Laly; Hilborn, Ray; Wall, Jake; Wittemyer, George; Badamja, Lkhagvasuren; Blake, Stephen; Boitani, Luigi; Breitenmoser, Christine; Broekhuis, Femke; Christianson, David; Cozzi, Gabriele; Davenport, Tim R. B.; Deutsch, James; Devillers, Pierre; Dollar, Luke; Dolrenry, Stephanie; Douglas-Hamilton, Iain; Dr€oge, Egil; FitzHerbert, Emily; Foley, Charles; Hazzah, Leela; Hopcraft, Grant C.; Ikanda, Dennis; Jacobson, Andrew; Joubert, Dereck; Kelly, Marcella J.; Milanzi, James; Mitchell, Nicholas; M’Soka, Jassiel; Msuha, Maurus; Mweetwa, Thandiwe; Nyahongo, Julius; Rosenblatt, Elias; Schuette, Paul; Sillero-Zubiri, Claudio; Sinclair, Anthony R. E.; Price, Mark R. Stanley; Zimmermann, Alexandra; Pettorelli, Nathalie
    In dry land ecosystems, mobility is essential for both wildlife and people to access unpredictable and spatially heterogeneous resources, particularly in the face of climate change. Fences can prevent connectivity vital for this mobility. There are recent calls for large-scale barrier fencing interventions to address human–wild life conflict and illegal resource extraction. Fencing has costs and benefits to people and wild life. However, the evidence available for facilitating sound decision-making for fencing initiatives is limited, particularly for dry lands. We identify six research areas that are key to informing evaluations of fencing initiatives: economics, edge permeability, reserve design, connectivity, ecosystem services and communities. Policy implications. Implementing this research agenda to evaluate fencing interventions in dry land ecosystems will enable better management and policy decisions. The United Nations Conventions on Migratory Species (CMS) and to Combat Desertification (UNCCD) are appropriate international agreements for moving this agenda forward and leading the development of policies and guidelines on fencing in dry lands.