# Stall Speed And Seagulls **URL:** \ **Category:** Factual Questions\ **Created:** [April 28, 2023, 1:39pm UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312 "2023-04-28T13:39:07Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![19USMC69](https://avatars.discourse-cdn.com/v4/letter/1/ac91a4/32.png) [@19USMC69](https://boards.straightdope.com/u/19USMC69)\ **Post date:** [April 28, 2023, 1:39pm UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/1 "2023-04-28T13:39:07Z")
To remain in the air fixed wing aircraft need to maintain airspeed above their stall speed. I assume this also applies to birds. If so, anyone know the stall speed of a sea gull who sometimes appear standing still? Obviously they are using the wind, but without it how fast do they need to fly to maintain altitude? ---
**Author:** ![Si\_Amigo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/si_amigo/32/2877_2.png) [@Si\_Amigo](https://boards.straightdope.com/u/Si_Amigo)\ **Post date:** [April 28, 2023, 2:36pm UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/2 "2023-04-28T14:36:09Z")
Birds are not fixed wing, they can adapt themselves so that they can hover like a kite with minimal effort. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 28, 2023, 2:36pm UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/3 "2023-04-28T14:36:46Z")
What do you mean, African or European seagull? ---
**Author:** ![ThisOneGuy](https://avatars.discourse-cdn.com/v4/letter/t/c0e974/32.png) [@ThisOneGuy](https://boards.straightdope.com/u/ThisOneGuy)\ **Post date:** [April 28, 2023, 4:50pm UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/4 "2023-04-28T16:50:02Z")
To give a less jokey reply, we can try to compare to airplanes. Using US measurements because that is what I have in my airplane spreadsheets. Going to [Wikipedia](https://en.wikipedia.org/wiki/California_gull) for the stats use a wingspan of 4.5 ft and weight of 1.5 lbs. Looking at [pictures](https://images.fineartamerica.com/images/artworkimages/mediumlarge/2/straight-below-angle-of-california-seagull-flying-overhead-cavan-images.jpg) estimate the aspect ration of about 10 leading to a wing area of around 2 ft^2. For a lift coefficient I’ll guess 2.5. This would be very high for an airplane but birds can alter their wing shape a great deal. They can’t actually hover without flapping but can fly very slow. Using the standard lift=1/2 \* density \* lift coefficient \* area \* speed^2, solve for speed in mph, weight in lbs, area in ft^2 and standard sea level density you get speed=19.7 \* sqrt(weight/(lift coefficient \* area). With the guesses above that comes out to 11 mph. Just a back of the envelope number, but should be in the ballpark. To fly slower than that they would need to flap to push more air down. You can see birds do that as they come in to land. ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [April 28, 2023, 5:34pm UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/5 "2023-04-28T17:34:45Z")
Birds can hover in a headwind. That meets the minimum stall speed requirements if the wind is strong enough. For a bird, so lightweight and with the ability to reshape its wings for maximum low-airspeed lift, it doesn’t take much air over the wings to make it happen. A steady breeze can be enough. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [April 28, 2023, 6:10pm UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/6 "2023-04-28T18:10:57Z")
I remember some claim that birds can fly as slow as 5-6MPH. However, birds rarely fly straight and level with no wind at slow speeds. Most bird flight involves gaining altitude initially, then using a headwind or thermal for more lift, and using gravity to gain speed in a descent. ETA: Hummingbird flight is obviously a whole different subject. ---
**Author:** ![jjakucyk](https://avatars.discourse-cdn.com/v4/letter/j/3d9bf3/32.png) [@jjakucyk](https://boards.straightdope.com/u/jjakucyk)\ **Post date:** [April 28, 2023, 8:48pm UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/7 "2023-04-28T20:48:23Z")
> [@gnoitall](#): > > Birds can hover in a headwind. And airplanes can take off “accidentally” in strong enough winds, if they’re not properly domesticated. [https://youtu.be/b\_WmjWAGkLI](https://youtu.be/b_WmjWAGkLI) ---
**Author:** ![md-2000](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@md-2000](https://boards.straightdope.com/u/md-2000)\ **Post date:** [April 29, 2023, 2:07am UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/8 "2023-04-29T02:07:20Z")
The flapping of the wings creates airspeed to lift the bird, also. Moving their wings in a rowing motion produces lift on the way up. Also, changing wing shape is like flaps on a plane, changing the stall speeb. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [April 29, 2023, 9:55am UTC](https://boards.straightdope.com/t/stall-speed-and-seagulls/983312/9 "2023-04-29T09:55:32Z")
I doubt that this observation changes anything here, but in strong winds, I have watched seagulls hovering, then moving backwards and having to adjust their wings to move forward. They have a lot of control.