2013 April Nature News – The Longest Year

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Greg-Young-Harris-hawks-learning-to-hunt-cooperatively

Young Harris hawks learning to hunt cooperatively

Many young raptors are lost to a variety of factors, including manmade ones, but the primary reason why the adolescent death toll is so high is because the stakes are so absolute. How does a first-year bird of prey survive to reach his second spring? Why do so few of them make it? And why are those that have made it worthy of even more respect?

Think of spring like the start of a year-long marathon. Spring is the season of life, of natural abundance, and it’s when animals of all shapes and sizes reproduce. That means droves of inexperienced predators and unassuming prey, each scrambling to learn its life lessons before the others. For a prey species like a rabbit, it’s all about discovering how to move, where to move, and how to watch for danger. A young raptor, eyeing that rabbit, has to commit everything he has to the chase: different birds of prey hunt in different fashions, according to their species, but the attack itself is a tremendous expenditure of energy. The rabbit’s dash for safety uses just as much energy as the raptor’s pursuit; the difference, though, is that when it comes time for the rabbit to “hunt,” it has the advantage inasmuch as grass doesn’t run very fast. Raptors learn lessons with every attempt, success or failure, the same as a human child. They develop new tactics that influence how they approach a target, how they give chase, and if they catch it, how they kill it while minimizing damage to themselves. Parents can only teach them so much; the predatory world is one of trial and error, if anything ever was. Every “error,” though, means wasted energy. Too many mistakes mean a hungry belly and not enough energy to rectify it. And that means starvation.

So how do birds of prey learn? Some of it is obviously instinctive, and the fundamentals are usually gleaned through observing their parents. As with most things in life, though, the truly important lessons come only through experience. A red-tailed hawk might catch a snake out in the middle of a field; how easy is that? It’s not running, and as long as that bird can get its foot around the snake’s neck, the reptile has no chance. A success like that bolsters the bird’s hunting repertoire, if only when serpent is on the menu. Conversely, zigging while a cottontail rabbit zags, and ending up with a face full of dirt because of it, only emphasizes the greater flight control needed against animals that depend upon their agility to survive. Though you might not think of it when it comes to wild animals, practice really does make perfect, and raptors do learn from their mistakes. Sometimes those lessons backfire, too, just like they do with human kids. A child might burn himself on the stove and develop a fear of ever boiling anything because the negativity of the experience was so awful. A raptor might have such a bad hunting attempt that it actually becomes discouraged from ever trying it again. Jackrabbits, unlike their smaller cottontailed kin, can’t easily take shelter in a burrow because of their larger size. While a cottontail rabbit will make a run for its (or any) hole to escape an attacking raptor, the jackrabbit will sometimes fight back. Blessed with powerful hind legs, jackrabbits have been known to turn tail to a swooping hawk, only to leap up and mule-kick. For an average 3-pound red-tailed hawk, a solid kick from an 8-pound jackrabbit can be a sobering experience, one that could effectively turn that young bird off of rabbit, or at least jack, for good.

Every meal, earned or lost, is a lesson for our young raptor. Too many lessons of the latter kind can lead to a sort of “hunger panic”: a starving raptor, of any age, will reach a point where it becomes desperate and begins attacking anything¸ including animals so large that it has little chance of actually killing it. It is a tragic state, but another reality of life in the wild. Though manmade changes to the environment certainly take a toll in many forms, the struggle for food is an inevitable constant. Those that learn their lessons quick enough are the ones who make it to spring 2014.

They’re the lucky, determined few, surviving day-to-day challenges that most of us couldn’t even fathom; they’re the ones who will one day pass on their legacy to future young birds, who must inevitably try their own luck in the unforgiving world outside of the nest.

1 Comment

One Response to 2013 April Nature News – The Longest Year

  1. Stephanie Belvedere says:

    While volunteering for many years for the Eagle Watch Project back in New Jersey, I was witness to this behavior of how raptors teach their partners how to hunt successfully. One pair in particular, where a young male mated with an older female. During the courtship the female appeared to be the more successful hunter of the two, but with patience and training she was able to teach her partner good hunting skills and in the end were able to breed up to 3 chicks each season….she taught him well…

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