Abstract

In ecologically pristine ecosystems, top-down effects of apex predators play a fundamental role in shaping trophic cascades and structuring ecosystems, but in human-modified landscapes anthropogenic effects may markedly alter the ecological role of predators. In particular, human-provisioned food subsidies represent a serious concern for the conservation of apex predators, even though little empirical attention has been given to this aspect in assessing conservation outcomes. To assess the extent to which anthropogenic food subsidies affected feeding ecology of a protected wolf (Canis lupus) population in a human-modified landscape, we integrated scat-analysis (n = 1141 from 4 packs; Jan 2005–Mar 2009) and winter field inspections of Global Positioning System telemetry re-locations (n = 595 clusters and 96 single locations from 5 wolves in 5 packs and 3 floaters; 2008–2011) of wolves living in a historical national park of central Italy hosting both wild prey and livestock at high densities. We revealed that livestock dominated the wolf diet (mean biomass = 63.3 ± 14.2% SD), secondarily supplemented by wild prey (36.7 ± 5.3%, mostly wild boar [Sus scrofa], roe deer [Capreolus capreolus], and red deer [Cervus elaphus]). During winter, we revealed a higher propensity of wolves to scavenge (72.5%; n = 91 feeding events) rather than killing prey, and feeding behavior was affected by prey type (i.e., domestic vs wild ungulates) as the large majority of scavenged carrions (75.8%) were livestock carcasses abandoned on the ground and died for reasons different from predation. Feeding behavior was not affected by social affiliation (i.e., pack members vs solitary wolves), indicating that pack members, even if aided by cooperative hunting, were equally likely than solitary wolves to scavenge rather than killing prey; yet, 27.5% of winter feeding events involved predation, exclusively targeted to wild prey. Our findings indicate that large livestock carrion subsidies may strongly depress predatory behavior in wolves, despite the occurrence of an abundant wild prey community, and have relevant ecological, evolutionary and management implications. Reliance on human-provided livestock carrion subsidies likely alters the ecological role of wolves by reducing their top-down cascading effects on the ecosystem, and this has relevant implications for the conservation of wolves and other apex predators in national parks. Accordingly, we call for more strict regulations to govern livestock management and practices and argue that, at least in national parks, conservation goals of apex predators need to explicitly consider their ecological role.

via Anthropogenic food subsidies hinder the ecological role of wolves: Insights for conservation of apex predators in human-modified landscapes – ScienceDirect

Abstract
Vocal communication in social animals plays a crucial role in mate choice, maintaining social structure, and foraging strategy. The Indian grey wolf, among the least studied subspecies, is a social carnivore that lives in groups called packs and has many types of vocal communication. In this study, we characterise harmonic vocalisation types of the Indian wolf using howl survey responses and opportunistic recordings from captive and nine packs (each pack contains 2-9 individuals) of free-ranging Indian wolves. Using principal component analysis, hierarchical clustering, and discriminant function analysis, we found four distinct vocalisations using 270 recorded vocalisations (Average Silhouette width Si = 0.598) which include howls and howl-barks (N = 238), whimper (N = 2), social squeak (N = 28), and whine (N = 2). Although having a smaller body size compared to other wolf subspecies, Indian wolf howls have an average mean fundamental frequency of 422 Hz (±126), which is similar to other wolf subspecies. The whimper showed the highest frequency modulation (37.296±4.601) and the highest mean fundamental frequency (1708±524 Hz) compared to other call types. Less information is available on the third vocalisation type, i.e. ‘Social squeak’ or ‘talking’ (Mean fundamental frequency = 461±83 Hz), which is highly variable (coefficient of frequency variation = 18.778±3.587). Lastly, we identified the whine, which had a mean fundamental frequency of 906Hz (±242) and is similar to the Italian wolf (979±109 Hz). Our study’s characterisation of the Indian wolf’s harmonic vocal repertoire provides a first step in understanding the function and contextual use of vocalisations in this social mammal.

via Characterising the harmonic vocal repertoire of the Indian wolf (Canis lupus pallipes). – Abstract – Europe PMC

“Life and Reality are not things you can have for yourself unless you accord them to all others,” philosopher Alan Watts wrote in the 1950s as he contemplated the interconnected nature of the universe. What we may now see as an elemental truth of existence was then a notion both foreign and frightening to the Western mind. But it was a scientist, not a philosopher, who levered this monumental shift in consciousness: Rachel Carson (May 27, 1907–April 14, 1964), a Copernicus of biology who ejected the human animal from its hubristic place at the center of Earth’s ecological cosmos and recast it as one of myriad organisms, all worthy of wonder, all imbued with life and reality. Her lyrical writing rendered her not a mere translator of the natural world, but an alchemist transmuting the steel of science into the gold of wonder. The message of her iconic Silent Spring (public library) rippled across public policy and the population imagination — it led to the creation of the Environmental Protection Agency, inspired generations of activists, and led Joni Mitchell to write lyrics as beloved as “Hey farmer farmer — / Put away the DDT / Give me spots on my apples, / but leave me the birds and the bees. / Please!”

via The Writing of “Silent Spring”

Isle Royale — One year into its effort to reestablish the wolf population on Isle Royale, the National Park Service and its partners have a problem: The new wolves keep dying and nobody knows why.

Since the park service began its relocation efforts in September 2018, 19 wolves have been transplanted from Minnesota, Ontario, Canada and Michigan’s Upper Peninsula. Three of the wolves have died, the most recent on Sept. 15. Another wolf left the island for mainland Ontario on an ice bridge in January.

via Park service looks to solve mystery deaths of Isle Royale wolves