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If you look at ducks taking off, they take off at a pretty flat angle, building up speed before they finally get some altitude. This takes a lot of distance, it seems, for them to get high in the air.

But this lead to a question. Are there water birds that, sitting on the water, take off at a more vertical angle without the long run-up?

The best I can think of are flamingos, who cheat by having their feet on the ground, in the shallow waters. Some birds will dive into the water, grab a fish, then fly out at a high angle, but that's a bit different from sitting on the water then taking off.

Many birds are able to perform a vertical or near-vertical takeoff, on dry ground. Can any birds do this while sitting on the water?

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    $\begingroup$ I think this question is receiving inappropriate close votes. There is nothing opinion-based about this question. $\endgroup$ – theforestecologist Jan 17 '18 at 6:05
  • $\begingroup$ Too bad you stipulate "sitting on the water"; that limits it to aquatic birds. A kingfisher can come up out of the water almost vertically. $\endgroup$ – anongoodnurse Jan 18 '18 at 23:44
  • $\begingroup$ @anongoodnurse Thanks for your downvote, it's becoming a tradition. $\endgroup$ – user24284 Jan 18 '18 at 23:45
  • $\begingroup$ Oh, the pitfalls of commenting! It's not a tradition; that's a pretty arrogant assumption. I downvote you occassionally, and only when you give a bad answer, like the one you deleted yesterday (?) or the day before. $\endgroup$ – anongoodnurse Jan 18 '18 at 23:47
  • $\begingroup$ It was not even close of being a bad answer, the same way this one is not. The problem with that question, once again, is that the OP was not clear enough, and it was ambiguous. Anyway, I deleted it because of a comment OP left. And thanks for the "arrogant". $\endgroup$ – user24284 Jan 18 '18 at 23:51
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Yes. A duck can be observed taking off near-vertically from the water's surface in this video. Watch the first duck to take off (from about 0:08). Immediately after take-off, the duck has a very low horizontal speed, and works to gain speed by a combination of flapping and vertically beating its tail. The full process is as follows:

Beat 1: The duck gives a sudden start. Both wings are beaten once on the water's surface to take advantage of the extra resistance the water provides, compared to air. The duck presumably also pushes down on the water with its feet below the surface in order to gain extra lift, but this is not visible.

Beat 2: By the start of the second downbeat, the duck's body is clear of the water, but the feet are obscured by spray.

Beat 3: The whole duck is clear of the water, and is gaining some horizontal speed. This wingbeat is accompanied by a clear vertical flap of the tail.

Beats 4 onwards: The duck continues to accelerate horizontally, remaining clear of the water.

Because the duck comes near-vertically off the water's surface, and remains airborne thereafter, I'd define the take-off as vertical, and the subsequent flight as transitioning into a duck's normal near-horizontal flight. Similar take-offs by terns can be seen in this video (but starting from a dive under the water's surface, see from about 1:02).

More generally, many waterbirds can take-off vertically from the water's surface, without requiring a run-up. All that is generally necessary is to face into the wind, and spread their wings. If the sea-surface is basically stationary, but there is wind, then any difference in speed between the air and the water can be exploited to generate lift.

If there is no effective wind (i.e., the water and the air are moving at the same speed), then the birds have to generate the lift for take-off by expending energy. Some species can do this, but it gets harder with increasing body-mass and wing-loading. I have personally observed a juvenile frigatebird (a species that generally weighs around 1 kg, but with very low wing-loading) lifting off vertically from the water's surface on a windless day. Note that frigatebirds would not normally land on the water (their feathers are not waterproof), and trying out a water landing seems to have been a play behaviour on the part of the juvenile.

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  • $\begingroup$ Love that you actually address water birds. I would upvote you, but your video doesn't support your statement about it. Maybe some literature or a different video? The question is, 'Can any birds achieve a vertical or near-vertical takeof while sitting on the water?' There are birs that can leave the water at a vertical/near vertical direction: kingfishers and penguins, for example. But they aren't starting by sitting on the water. $\endgroup$ – anongoodnurse Jan 19 '18 at 17:30
  • $\begingroup$ @anongoodnurse the OP has asked the question in two forms - the one you highlight, and the softer "Are there water birds that, sitting on the water, take off at a more vertical angle without the long run-up?". The video unambiguously answers the 'soft' version, and if the lift-off is defined as the act of getting into the air, given sustained flight after that (as in my definition), I believe it also answers the 'hard' version that you have highlighted. $\endgroup$ – bshane Jan 19 '18 at 21:54
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The answer to your question ("are there water birds that take off at a more vertical angle?") is probably this: no.

The explanation is quite simple: on land, the hindlimbs provide the main force for the vertical take-off while the wings (forelimbs), obviously necessary for continuing the movement generated by the hindlimbs, are not the primary take-off accelerator.

According to Earls (2000), that studied the take-off in some species:

The hindlimbs of S. vulgaris and C. coturnix produce the primary acceleration of take-off. The wings act either after the hindlimbs have finished producing force (S. vulgaris) or during the hindlimb action (C. coturnix), but in both species provide only 10–15 % of the total take-off velocity. (emphases mine)

Also, regarding extrapolating the conclusion to other species (idem):

Comparison with one other avian species in which take-off kinematics have been recorded (Columba livia) suggests that this could be a common pattern for living birds.

Now the problem becomes clear: sitting on the water, an aquatic bird cannot use its hindlimbs to provide the acceleration for the take-off. It has to use only its wings.

Then, we can suppose that using the wings for providing 100% of the acceleration in a vertical take-off is:

  1. Energetically expensive, or
  2. Physically impossible for the bird*.

*When I say physically impossible I'm not implying that this is "impossible according to the laws of physics"... I'm just saying that the bird doesn't have the necessary strength.


Source: Earls, Kathleen, KINEMATICS AND MECHANICS OF GROUND TAKE-OFF IN THE STARLING STURNIS VULGARIS AND THE QUAIL COTURNIX COTURNIX. The Journal of Experimental Biology 203, 725–739 (2000)

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  • $\begingroup$ Basing an answer on "this could be a common pattern for living birds" is iffy. $\endgroup$ – anongoodnurse Jan 18 '18 at 23:45
  • $\begingroup$ I'm just quoting the paper. $\endgroup$ – user24284 Jan 18 '18 at 23:49
  • $\begingroup$ What comment did I delete? $\endgroup$ – user24284 Jan 18 '18 at 23:52
  • $\begingroup$ It's still there! And I said that because you downvoted my other answer, which was not a bad answer, and now this one in the following day... that's why I wrote "tradition". $\endgroup$ – user24284 Jan 18 '18 at 23:55
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    $\begingroup$ I don't believe this is a bad answer. It is a bit assumptive, but highlights some useful facts to make a plausible hypothesis. $\endgroup$ – Johnny Jan 20 '18 at 13:41

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