Pretend that you are one of the trout regularly stocked in Tempe Town Lake. Plenty of water, ample companionship: avoid the occasional baited hook, and it’s a pretty good life.

One morning, a shadow falls over your idyllic paradise. You’re not that familiar with the sky, being a fish and all, but you do recognize light from dark. And you instinctively know that activity on the other side of the water’s surface is a harbinger of bad things to come. Your fellows scatter to the deep. You move to follow, but before you can make it down to safety, that shadow is upon you.

Now switch roles, putting yourself in the place of that shadow. You, an osprey, have perched on a nearby freeway light since dawn, waiting for some flicker of disturbance in the lake below to betray your breakfast. Predator or prey, both know to watch for shadows: the merest hint of movement is often the only warning there is. In today’s battle, you were quicker to spot the opportunity, and now you’re airborne again, sopping wet, but otherwise victorious. You’re made for this lifestyle: the pads of your feet bristle with barbs, giving you the perfect tools for wrestling down a slimy, writhing snack. You’re a corsair of the waterways, one of the most specialized predators in the raptor world.

You fish. And you’re good at it.

Osprey goes fishing.

You’re on your way back to your perch, not a care in the world, when suddenly, a shadow descends upon you. It grows steadily bigger; you dodge and weave, but it stays right on your tail. You don’t have time to turn and look, but you know what it is. The undignified cackle of your tormentor belies one of the great predators of North America. Aggravated and afraid, you let go of your fish; you plundered it from the waves, but there’s no honor among thieves.

Now switch your perspective to that of the final victor. You terrified the fisherman into letting go, and before that easy meal hits the surface, you snatch it up. You’re a Bald Eagle, and you let that osprey do the hard work for you. It’s not honorable, but then survival isn’t a gentlemen’s duel.

It’s life or death.

Piracy is a fact of life in the animal kingdom. Every single action a predator undertakes expends energy; the more wasteful one is, the more likely it won’t have the reserves needed to score that next meal. And since those meals are the only way to sustain the perfect engine that is a hunter, it’s easy to fall into a lethal spiral of growing lethargy and looming starvation. Thus, they take what they can get, even if it means stealing it from others. Bald Eagles are no more nefarious than any other raptor. They certainly can, and do, fish for themselves; they simply have the benefit of being apex predators. If an osprey had the tools to bully its way to the counter, it would; but it doesn’t, and so it’s back to the lake for another go at it.

Raptors steal from one another the same way that lions and hyenas do. It’s a common theme for all predators, really. Practically every carnivorous animal flies the Jolly Roger, because the alternative is certain death. The only thing more energy efficient than stealing someone else’s kill is eating something that died of its own accord. Vultures aren’t the only ones with a taste for carrion; even the most regal eagle will gladly dive in. Mighty Red-tailed Hawks, among the biggest and most common hawks in North America, stop to eat grasshoppers as readily as they’ll chase down jackrabbits. They’ll also kill owls, and vice versa, in order to eliminate potential competition. No step can be spared in the quest to live.

Bald eagle bullies a raven off of his salmon.

For a bird of prey, protecting a meal is as much an imperative as securing it. Raptors aggressively shield their captured prey in a display known as “mantling,” extending their wings around the carcass like a protective dome. They simultaneously puff themselves up to look as dangerous as possible. Depending upon the bird and upon the meal, they’ll often carry their food to a secluded spot, whether up in a tree or down below a bush. The best case scenario is to avoid being seen in the first place. But if a rival does happen upon them, mantling makes it clear that they won’t give up without a fight.

Whether it’s truly worth battling over depends upon the circumstance. An osprey can more easily grab another fish than tangle with an eagle. But a raptor that’s hungry enough – or desperate enough – might have no choice. In that case, mantling isn’t camouflage, and it’s no mere bluff. It’s a threat:

Pirates, ye be warned.