Sunday, October 17, 2010

Great blue heron wins war of nerves with osprey

Although a Great Blue Heron is a large but delicate-looking bird, it can hold its own against powerful raptors like ospreys

Simply Living
(First appeared in Orlando Sentinel October 17, 2010)

Which is the more dominant bird — the great blue heron or the osprey?

If you had asked me that question last week, my answer would have been "osprey." I would have been wrong. Here's what happened to change my mind.

I was standing outside enjoying the view. The lake was calm. Most of the morning mist had disappeared, and the osprey that spends nights perched 6 feet above the water on the bamboo platform had flown off to do whatever it is ospreys do early in the morning.

In its absence, a great blue heron that had been quietly fishing in the shallows flew up to the platform. The heron, a tall, slender bird with long legs and a sharp beak, was using the perch to do a bit of preening. From my shoreline observation post, I was thinking about how quickly the heron commandeered the platform once the osprey departed. The heron must have been waiting for the fish hawk to fly off so it could take its place.

While those thoughts filtered through my still-sleepy mind, the osprey returned. The first indication of an impending confrontation came with the osprey's high-pitched, piercing whistle.

"Kew-kew-kew," the broad-winged bird cried as it approached the platform in a low, swooping flight. Once I realized what was happening, I expected the heron to retreat. Instead, it stood firm. As the fish hawk dived down, the heron stretched up, its sharp beak pointed defiantly toward the oncoming assault.

The heron's steadfast response surprised me. Ospreys are large, commanding predators. Their strong, 2-foot-long bodies feature a 5-foot-wide wingspan, sharp talons and a curved beak capable of tearing apart flesh with ease. Given its powerful presence, I expected the osprey to triumph. The osprey must have expected the same because it seemed surprised by the heron's defiant response. Just before impact, the osprey made a quick U-turn, flying off before circling about for another go-round.

The osprey's second attempt to reclaim its post seemed mostly for show. Now that it was prepared, the heron appeared even more determined to stay on the perch. With its long neck fully extended, its sharp beak pointed upward and blue-gray feathers ruffled, the great blue heron headed off the osprey's second attack with a vocalization of its own.

"Kraaaak," it croaked. Although not nearly as impressive as the osprey's shrill shriek, the heron's throaty call effectively demonstrated its determination and dominance. In a strangely guttural tone, the long-legged wader seemed to announce: "I'm here now, so go away. You left your perch, and when you did, you relinquished all rights. Fly off now. Be gone."

The osprey did fly away. The heron remained on the platform, where it resumed preening. Apparently, in the world of fish-eating water birds, a loud voice, sharp talons and sturdy body are not enough to guarantee dominance. Even frail-looking, graceful birds can reign supreme if they muster sufficient mettle.

Before observing the two birds in conflict, I would have predicted an osprey victory. Ospreys are fierce-looking, intimidating predators, while herons appear to be non-aggressive and shy. If I had been on the platform and an osprey was dive-bombing me, I would have jumped off in a millisecond. I guess that means I'm easily intimidated. It also means the heron is not.

I have no idea why the great blue heron was so intent on staying put or why the osprey, having left the platform, needed to make some sort of territorial claim. What I do know is that occasionally steadfast determination trumps unmitigated brute strength and that —– at least in the animal kingdom — differences can sometimes be resolved without either party being hurt.

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