Grebes have fine control over their buoyancy. They can sink at will by
squeezing air out of their plumage (by flattening their feathers) as well
as by expelling air from their internal air sacs. According to Birds of the
World, the structure of their contour feathers includes coiled barbules
that may serve to trap water and this may also give them a sleeker, more
hydrodynamic profile, creating less turbulence as they glide through the
water.
These adaptations allow them to float or sink to varying depths with ease.
Unlike ducks, they don’t have to propel themselves at speed to keep from
popping back up to the surface.
On Wed, Aug 6, 2025 at 11:51 AM wagtail1997 via groups.io <orcorba=
<cox.net...> wrote:
> *Group,*
> *Mason Regional Park (Irvine, Orange County, CA) has a high density of
> Pied-billed Grebes right now. At least 3 of the 14 are showing quick
> sinking behavior. I've studied that for the last two weeks and come up
> with videos on the behavior, analysis of the sinking, a summary of possible
> mechanisms, ecology, and more. All that is missing is to actually find a
> scientific paper on the behavior, even after doing some online searches for
> such studies. Anyone have a reference that I can add to my show notes?
> The Grebe's legs and feet have a role in the late stages of the sinking.
> The head behavior is interesting and lags the submersion of the rest of the
> body. I raise more questions than I can answer about the behavior. **https://youtu.be/v95FQgHPxq8 > <https://youtu.be/v95FQgHPxq8>* > Joel Weintraub
> Irvine Ca
>
>
>
