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“HOW LARGE Predators Manage the Cost of Hunting” is the title of an article in Science, October 3, 2014, the weekly magazine of the American Association for the Advancement of Science.
The fascinating theme in this Science article by John W. Laundré is that different felines, specifically cheetahs and pumas, have different strategies of Cat and Mouse. Yet both strategies display a similar conservation of energy.
The cheetah (Acinonyx jubatus) is renowned as the fastest of land animals. See http://wp.me/p2ETap-1gc, “Cheetahs: Sports Car Felines.” High speed is paramount in the cheetah’s subduing prey.
By contrast, the puma (Puma concolor), also known as the cougar, is a sit-and-wait hunter that ambushes its prey. The puma shares this hunting strategy with the lion and other big cats. See http://wp.me/p2ETap-1BN, “Bears and Cougars Oh My.”
Researchers studied the energy costs of seeking prey versus subduing it. Notes author Laundré, “Intuitively, one would think that the extreme physical exertion of chasing and pouncing on prey would far outweigh the searching process.”
However, to assess these energy costs, researchers have used an innovative piece of equipment, a SMART collar (as in species movement, acceleration and radio tracking). Two detailed articles in Science, October 3, 2014, are cited: “Flexible Energetics of Cheetah Hunting Strategies Provide Resistance Against Kleptoparasitism,” by David M. Scantlebury et al.; and “Instantaneous Energetics of Puma Kills Reveal Advantage of Felid Sneak Attacks,” by Terrie M. Williams et al.
The studies show that, even with their decidedly different hunting strategies, these two species of big cats both expend much more energy in seeking prey than in subduing it.
Although subduing prey is evidently energy-intensive, the time is brief. Regardless of species, carnivores tend to capture their prey quickly or give up. In fact, Williams and colleagues found that pumas adjust their energy investment on prey size, not overly exerting themselves on smaller meals.
Both pumas and cheetahs have evolved ways of reducing this energy demand. The puma does this through its sit-and-wait approach. The cheetah minimizes its time of stalking.
Scantlebury and his associates also discuss “kleptoparasitism,” the theft of another animal’s prey, particularly, by lions or hyenas. If prey abundance is high, the cheetah saves energy by abandoning a kill and seeking another, rather than defending it.
Notes Laundré, “The overall conclusion of the two studies is that evolution has honed the behavior of these two carnivores to maintain the balance of energy needed in finding and subduing a reluctant food source.”
This also raises the issue of human activity disrupting the balance. Human-attributed loss of vegetation makes it more difficult for the sit-and-wait predator to ambush prey. Human-reduced abundance of prey hampers both types of predator strategy by complicating its more energy-consumptive phase.
SMART collars could lead to further research on behavior as a function of time since a meal. Researchers also talk of the “landscape of fear,” wherein prey alter their behavior based on predator efficiency, and also the predators’ perspective, the “landscape of opportunity.”
It’s quite a Cat and Mouse game. ds
© Dennis Simanaitis, SimanaitisSays.com, 2014