I’m Learnin’ to Fly

Osprey practicing flightI’m always on the lookout for wildlife, even when I’m driving 100 km/h down a highway. My sister used to always get annoyed at my penchant for pointing out hawks circling overhead or braking suddenly to check out some mergansers along the lakeshore.

Well, the other day, my wandering eyes paid off. I spotted frantic flapping atop a hydro pole and had to pull over. It was definitely worth the stop, as I found myself watching a couple of juvenile Ospreys testing out their wings under the watchful eyes of their parents.

Over and over again they flapped furiously, gaining loft, but holding onto the branches of the nest like a ballerina would a barre. It was truly an amazing moment to witness.

Birds aren’t born knowing how do fly, just like humans aren’t born knowing how to walk. First off, it takes time to develop the enormous pectoral muscles needed to create and sustain the thrust required to get them off the ground and keep them in the air. Although most species lighten the load with hollow long bones and lungs that extend into air sacs throughout much of the body, the muscles responsible for flapping their wings make up 25-35% of a bird’s mass. These take time to develop; how much varies from species to species.  In Osprey, it’s nearly two months.

During that time, they practice, flapping and fluttering awkwardly and sometimes falling altogether. In some species, parents encourage the process by landing farther and farther from the nest with each food delivery, forcing their offspring to come out of their safe haven.

That fragile period in a bird’s life known as fledging is a bit of a behavioural tug-of-war between the demands of the young and the desires of the parents. It’s really not all that unlike human parents trying to get their grown up children to move out. Young birds don’t really want to leave the nest. I mean, why would you? You’re relatively safe, cozy and mom and dad bring you food several times a day. Sure, it gets a little cramped being crammed in there with your siblings and your room isn’t always the cleanest, but you don’t have to go out and work for your food. What’s not to love about that?

The thing is, parent birds need a break by the time young are ready to fledge. They can lose a significant amount of their body mass as a result of the energetic demands of feeding and protecting their offspring. Some species still have time in a season to raise a second brood, potentially doubling their genetic payoff. So, they want to get the kids off and into the world as soon as possible. Scientists have been studying this clash of wills for a long time now, measuring the costs and benefits on both sides of this ‘parent-offspring’ conflict.

When that conflict is resolved depends a lot of the species. Small songbirds usually only spend a couple weeks in the nest and then another couple of weeks following mom and dad around, figuring out how to feed themselves, but still begging for a handout whenever they can. For raptors, the period is much longer; osprey can take up to 17 weeks to become independent. It takes time to learn the art of hunting your own prey.

Young raptors learn by watching and again, through practice. I’m sure that for each generation of raptor there are mice and fish out there who’ve had a few years shaved off their lives from the terror of a near miss by a rookie owl or osprey careening towards them.

Still, they eventually get it right. They have to; at some point, mom and dad decide that they’ve invested enough into this generation and cut the chord. Because, regardless of the species we all must stand on our own two feet.

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14 thoughts on “I’m Learnin’ to Fly

  1. What a wonderful photo and explanation. We have an osprey nest near here and boy the noise those fledglings make ! “Mom bring it HERE. Please. Please. PLEEEEEEEEEEEZE!”

    • Thanks, Sybil. That was my first osprey nest. You’re lucky to have them. Juvenile birds can definitely be demanding. I used to study saw-whet owls and you could hear the young screeching for food in the darkness. It’s always a neat thing.

  2. Hi Heather, Just bounced over here from Cindy Kilpatrick’s blog and am I ever glad I did! There’s a large population of Osprey in the area here around Rice Lake and, I have no idea why, but for some reason I feel bound together with these gallant little raptors… They have captured my heart completely. Thanks for your blog piece on our young winged “bandits”, D.
    P.S. Many thanks also to the volunteers who install and maintain the Osprey nesting stands.

    • Hi Deb! Thanks for stopping by. I love Cindy’s blog, so many awesome pictures. Sounds like you have a pretty awesome place to live. Where’s Rice Lake? I’m glad to hear you have a network of people working to maintain these amazing birds.

      • Hi Heather, Rice Lake glistens amidst the rolling hills of the Oak Ridges Moraine: between Hwy 28/Bewdley on the west, Peterborough County on the north, Northumberland County to the south and Roseneath/Hastings/… on the east… all in south-eastern Ontario and yes, it IS awesome! : )

      • After reading a bit more (you mentioned a lake north of Gan), I’ve realised that you’re not that far east of here. Howdy neighbour (speaking of having a great place to live!)

  3. Wonderful story to go with a beautiful photo! We are also fortunate to have an Osprey nest nearby (on a telephone pole platform like in your photo). We know the same ones return each year because one has a jess strap attached to its leg (unfortunately). At some point, I guess the young Ospreys literally outgrow the nest…not much room in there!

    • Thanks very much! Of all the raptors in North America, ospreys seem to be the ones most attracted to telephone and hydro poles for nesting. Despite the danger of electrocution, they are a most stable platform than trees. You’re right, like most raptors, the young literally outgrow the nest. Out my way, we’ve had an eagle’s nest fall apart three times now from the stress of too much weight.

      Interesting that your osprey had jesses at some point. I don’t think I’ve ever come across one that’s been used in falconry. Glad to hear it’s doing well and successfully breeding.

  4. I came by here just after you posted and I thought I had left a comment…must have been distracted. I thought I had told you about a nest my hubby & I used to watch at a small nearby lake. They had nested in a dead but still standing tree on a sort of narrow isthmus that almost bisects the lake. We could canoe to almost right under the tree and it was a thrill to see the gangly young when they got large enough for us to see over the lip of the nest. Unfortunately, the tree finally did what trees do and one spring it was laying in the lake with the nest invisible below the water. I don’t know where the couple went the following year; I hope they found another, even more secluded location.

    I love your comparison of the young birds holding onto the nest “like a ballerina would a barre”, and the narrative description of the process of cutting the chords. I suspect birds aren’t as ambivalent about it as most of us humans are.

    Beautiful art as always, Heather and an altogether wonderful post.

    • Hi Cindy! Thanks for sharing your osprey story. It’s amazing what you can sneak up to in a canoe. Too bad it fell over. We had a few eagles’ nests go down this year. Unfortunately, they had young in them. I’m hoping they’ll renest next year.

      I’m glad you enjoyed the post. Watching those birds learning to fly was such a treat, I just had to write about.

      I hope all is well.

  5. Oh so sorry! I was reading both you and Kait at the same time and, you’re right, crossed signals (and wrong direction; )

  6. Astonishingly beautiful image, Heather! The colours, the movement. I’ve just been staring at it for about a minute! Then I went on the wonderful words, charting the lift in a bird’s life and am grateful yet again for such clear and evocative prose detailing the natural world. And to show just how small the world is, I used to go to Rice Lake in the summers with my parents!

    • Hi Julian. I’m glad you liked the image. I had been wishing for a longer lens as I’d been watching them. My 300 was stretched to its limit and I just wanted to get closer.

      It is a small world. I’ve never been to Rice Lake, at least not Rice Lake, Ontario. Something tells me one of our 110,000 lakes in Manitoba has that name too. There are so many beautiful waterways to visit and not nearly enough time.

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