For cat owners, it’s not hard to imagine that the deadliest hunter on Earth has four paws and whiskers. Especially if your moggy likes to bring you ‘gifts’. Certainly, a little birdy is likely to agree: The Mammal Society have estimated that the UK’s 9 million pet cats could bring home 92 million dead animals per year, 27 million of them birds.
Scale that killing potential up to tiger or leopard size and you’d have the world’s most successful predator – or would you?
Big cats are undoubtedly finely-honed hunters. They are apex predators with fearsome claws and powerful jaws. Tigers are strong swimmers and leopards are excellent climbers, so they can cover a variety of landscapes during a hunt.
To remain undetected they hunt under cover of darkness
Yet in Kruger National Park, South Africa, six out of seven leopard hunts end in disappointment. Tigers hit their target even less often. George Schaller’s studies of Bengal tigers estimated that as few as one in 20 hunts actually results in a kill.
These estimates were made from observations and obviously vary significantly depending on how much prey is available and the experience of the predator. Their sneaky nature also makes hunting behaviour notoriously difficult to study.
Even with their renowned camouflage, it can be difficult for these big cats to hide so they rely on the element of surprise to catch their prey. They are stealthy hunters, stalking and ambushing their targets and using the landscape for concealment. To remain undetected they hunt under cover of darkness but can fall foul of the full moon.
Out on the plains, cheetahs obviously have an advantage in the chase since they are capable of running at 58mph (93km/h). But even they only catch their prey half the time.
Looking at the royalty of roaring cats, it seems teamwork can help. Lionesses hunting in a group or pair can be twice as successful as a lone animal but still succeed less than 30% of the time.
They only hunt once or twice a day and whatever they catch is shared
Hunting as a group pays off better for wild canines. African wild dogs for example increase their success rate to 67% in a pack of 20 dogs. They can target animals twice their size and sometimes even bigger.
Similarly, grey wolves can take down enormous American bison weighing up to 900kg. They achieve this through efficient cooperation, running a relay race that eventually exhausts their prey so they can strike.
However, all that running takes it out of the dogs. They only hunt once or twice a day and whatever they catch is shared.
For a really impressive daily death tally, you have to set your sights on a much smaller animal – the army ant.
This hunter also gets by with a little help from its friends. A single colony of army ants can capture up to 30,000 prey items in just one day. But the numbers are key: a colony can number half a million ants.
It’s the dragonfly brain that holds the secret to this remarkable success rate
The insect world is home to reportedly the most successful hunter on Earth. In 2012 researchers at Harvard University, Massachusetts, US, found that dragonflies caught up to 95% of the prey they chased.
This deadly record is down to an array of adaptations including complex eyes specialised to detect black spots against the sky. Their wings are also powered by individual muscles that work together for amazing acceleration and agility.
For neuroscientist Anthony Leonardo, it’s the dragonfly brain that holds the secret to this remarkable success rate.
“The brain uses a highly optimised hunting strategy that allows the dragonfly to predict where the prey is going and the appropriate muscle commands to intercept it,” he explains.
“Dragonflies are opportunistic and will consume any flying prey roughly the size of their head or smaller – bees, moths, flies. Mostly they eat small insects like mosquitoes [and] midges - but larger species will even catch other dragonflies.”
The whales consume as much as 4 tonnes of food a day
“In my lab, where we feed them exclusively fruit flies – more difficult to capture than common outdoor prey – they catch about 80%... This is still quite impressive as the fruit flies are moving quite fast, about 1 metre per second.”
In Leonardo’s lab at the Howard Hughes Medical Institute, Maryland, US, researchers have taken on a tremendously fiddly task to study the insects in flight. They have fitted tiny backpacks to dragonflies.
“We are using the telemetry backpacks to record from both steering neurons and wing motor neurons while the dragonfly catches prey,” says Leonardo.
“The purpose of these studies is to understand how brain cells work together to model the world and make predictions… about prey movement and desired steering commands.”
There is one more contender for the title of most successful hunter. But to many of us, it does not seem to be a real hunter at all.
Blue whales are the largest mammals ever known and can reach up to 34m (111ft), almost as long as a jumbo jet.
Taking down a massive target certainly looks dramatic
To maintain their impressively massive figures, the whales consume as much as 4 tonnes of food a day. Their preferred diet is small crustaceans known as krill. To hit its calorific target, a single blue whale eats 40 million krill per day.
If you think opening wide to slurp down some seafood doesn’t exactly count as hunting you underestimate the marine mammals. The energy it takes to open their huge jaws means they will only do so in the presence of a significant swarm of krill. In the summer months blue whales search the ocean for scattered riches that will see them through the bleak winter.
So choosing the world’s deadliest hunter all depends on your interpretation of deadly. Taking down a massive target certainly looks dramatic. Picking off prey with a superb success rate can’t fail to impress. From our perspective consuming millions of lifeforms in a single gulp is another level of lethal, but to a whale it’s just dinner.
For all of these wild hunters it’s survival that motivates their predatory behaviour. Domestic cats are fed and cared for, so it’s only residual instinct that drives their killer urges. Of course, humans judging cats for taking innocent lives does sound a bit like the pot calling the kitten black.