My opinion is based on fifty years of observing birds. In my experience, it is much easier for a waterbird to take off from the water than from land for the reasons I have explained.
Grebes and loons are unable to stand erect on land and must take off from water. Likewise diving ducks generally require an extensive stretch of water to take flight.
To add to this: the reason that grebes & loons can’t take off from land is that their legs are much further back on their bodies than those of ducks. This makes for swimming and diving that is much more efficient, but walking that is awkward at best. Often loons walking on land will end up with their chests in contact with the ground as they push themselves along with their legs. Not exactly optimal take-off conditions.
This gets back to Chronos’s point about whether the swan species could survive if it couldn’t take off from land. The case of the loon implies that it’s not as far-fetched as it might seem: at some point in the loon’s evolutionary history, some proto-loon discovered that advantages of diving & swimming really well were greater than the disadvantages of not being able to take off from land.
To expand a little, I’m comparing fairly calm conditions when the water is flat. Under such conditions a water take off should be easier than even from the flattest land. If it’s blowing a gale, then waves could interfere and a land take off could be easier. But strong wind will make a take off easier in general, since the bird will experience lift if it opens its wings even when it is standing still.
In fact, four of the 20 or so species of grebes are flightless (or were, since two of them are now extinct due to human influence). They all live (or lived) on large isolated lakes where they evidently found flight unnecessary.
Can they take off from treadmills?
That series of shots is indeed convincing . As I mused in a previous post , I just wonder if all species of swan are able to take off from dry land, or whether it is a skill reserved for the privileged few.
Not being an ornithologist I have no idea what species the swans in the Queen’s Park in Edinburgh belong to (the swan I helped rescue had flown from there) but i would bet a substantial amount that nobody has ever seen any these “royal” swans ever take off from dry land. Which of course doesn’t prove that they couldn’t, if they had to …
In Holyrood Park, they are mute swans.
I wonder how well some birds could take off from wet land, like mud. If their can’t act like paddles and they can’t get a sure grip then maybe some are trouble. I’m sure with a decent wind any bird that fly can take off from any terrain though.
I would assume it’s all a question of body weight … seagulls can take off from a standing start , like a Harrier jump jet. I would imagine that at the other extreme, an albatross would need an aquatic runway the length of a football pitch.
Albatrosses pretty much need strong winds to take off wherever they are.
This thread has made me realise how abysmally ignorant I am of the behavior of sea-birds, and has got me wondering about several aspects of their behavior.
For example, do albatrosses ever actually touch down in water from choice ? Or do they prefer to land on cliff tops, from whence a take-off would presumably be much easier ?
I have also gotten to thinking about gannets …when they dive and impale their prey, what is the take -off procedure …is it a rapid vertical emergence, like a ballistic missile from a submarine, or do they rise to the surface and then do the whole runway thing ?
Albatrosses made me wonder about this.
They certainly touch down in water voluntarily on the ocean. It’s likely they’ll catch some wind in a short time. Plenty of them live on atolls with nothing of height to jump from but plenty of runway space and frequent winds. I don’t what other habitats they might occupy.
I’m not sure on swans, but Grebes have great difficulty in taking off from dry land.
Grebes are a small bird similar to a duck, but they are not ducks nor related to ducks.
If you look at their feet you will see why right off, they can not walk, at least not very well at best, their legs are also way way back on the body makign them nose heavy in walking, but work great for swimming/diving.
I do know that not all birds have the lift to hop n go, some do indeed need to build up ground speed to get lift, ducks for example need speed to lift.
Some birds like the little Grebe can not move on land fast enough to lift, just lack the feet for it.
Swan Sanctuary says they can take off from dry land but need about 30 yards of runway.
I do believe that this is the same link to which I referred in my OP.
Thanks nonetheless …
If a bird can’t take off from dry land, then I expect that it would be extremely careful about picking its landing spot in the first place.
I’m not trying to ruffle your feathers or anything, but are you finally convinced that swans can take off from land? Colibri is a biologist and a recognized expert on birds. Please don’t tell me that you’re still harboring the idea that swans are unable to take off from land.
See post#25.
AFAICS, there are several different species of swan, and it certainly appears that some of them do in fact land on, and are able to take off from, solid terrain.
The swans which are found in the UK, which I am informed above by Baron Greenback are mute swans, I am still in doubt about.
There’s also Bewick’s and Whooper swans, but they are winter visitors only. The resident swan population is mute swans.
And all of the sheep in this field are white on this side, at least.
That’s a pretty long [del]treadmill[/del] runway. Easy to see how people could mistakenly believe swans couldn’t take off from dry land if they were grounded in some confined space unable to get up in the air without a good wind assist.
