Amazing stuff! Is this just coincidence or learnt!
"... In a fascinating cycle of foraging for both pumas and their prey, decomposing ungulate carcasses deposit elevated levels of nitrogen, carbon and other valuable elements that improve the chemistry and nutrient makeup of soil and plants. These changes may even influence where ungulates, such as elk, congregate and feed, given their preference for nitrogen-rich food. Pumas, because they hunt only select areas that give them an advantage, are creating nutrient-rich hotspots that may continue to improve their future hunting success over time. ...
Pinpointing the locations of GPS-collared pumas in the Greater Yellowstone Ecosystem, scientists identified puma kill sites to collect and analyze 1,007 soil samples from 172 ungulate carcasses and 130 plant samples from 65 sites. Along with increased nutrients in soil and plant samples, researchers found kills were concentrated to a tiny fraction of habitat (4%) favoring pumas' preferred stalk-and-ambush strategy. ...
Unlike other carnivores such as gray wolves that dismember their kills, pumas maintain intact carrion and experience high levels of kleptoparasitism or stealing of their kills. This results in pumas contributing a disproportionate amount of food to other wildlife, with pumas consuming approximately a third of the overall weight of their prey, on average, and the rest supports diverse scavengers, flora and fauna. ..."From the structured abstract:
"Context
Carnivores influence the spatial heterogeneity of biogeochemical processes in ecological communities through predation and the deposition of animal carcasses, and these processes may lead to positive feedback loops that influence large-scale patterns of nutrient cycling.
Objectives
We assessed whether ambush predator foraging impacted soil chemistry and plant forage quality, and then scaled these effects to the landscape to assess whether carnivores contribute to heterogeneity in resource distributions.
Methods
We measured total nitrogen (N) and N stable isotope composition (δ15N) of soils and plants at 172 ungulate carcasses killed by mountain lions in the Yellowstone Ecosystem, USA. We measured kill rates and estimated the probability of a mountain lion foraging in any location to scale their carrion contributions to the landscape.
Results
Carcasses altered total nitrogen N and δ15N of soils and plants, and changes in δ15N suggested that plants absorbed significant N from carcasses. On average, plant δ15N at kill sites increased by 2.3 milles (‰), which is large compared to the 6.3 ‰ range of variation in local plants across xeric and mesic systems. We conservatively estimated that resident mountain lions in our study area annually contributed the carrion mass of a blue whale, or 44.1 kg of carrion and 1.4 kg of N per km2. We also determined that mountain lion foraging was concentrated in just 4% of our study system.
Conclusions
Ambush carnivore foraging may contribute to landscape-scale heterogeneity in nutrient distributions, and set the stage for positive feedback loops between carnivores and prey that drive biogeochemical processes."
Large carnivore foraging contributes to heterogeneity in nutrient cycling (no public access)
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