Imagine the problem faced by osprey parents when it comes time to boot the chicks from the nest. Winter is coming; chicks must learn to fend for themselves; soon they must migrate thousands of kilometres on their own. Time is short—they must leave the nest. (These chicks will return as adults in a couple of years when they are ready to breed.)
Left to their own devices, osprey chicks would hang around and live off their parents for a few months longer, which is what they do do in tropical climes. Local parents cannot afford to let that happen: children must be persuaded to leave home.
Starvation is the main tactic. Enticement is another.
As the time for fledging approaches, parents decrease the number of fish being brought to the nest. Indeed, the chicks even begin to lose weight.
Parents now taunt their hungry chicks with a couple of tactics: They bring inedible things to the nest; They catch a fish and then repeatedly display it by flying past the nest and even dropping it nearby—but do not deliver it to the nest.
The increasingly desperate chicks respond by exercising their wings in the nest, and eventually by heading out on their own.
A parent returns to the nest carrying only a stick. At this time of year, I have also seen them merely deliver leaves. This famished chick looks up as if to say: “What the heck? Bring me something I can eat.”
Besides starving their chicks, parents taunt them by flying past the nest with a fish that is never delivered. Here, an adult flies towards the nest with a fish, but did not share it.
The taunting tactic of displaying a fish during a flyby enabled me to get my best ever shot of an osprey packing a fish. A male kokanee was used for this tease.
The increasingly desperate chicks respond by exercising their wings in the nest. “We will show those stingy parents of ours; We will head out and get our own food.”
“Just before we separate, let’s pose for a farewell family portrait.” Ah, the memories.