What’s with those spindly legs and weird knees?
Those aren’t weird looking knees on those thin sticks of a leg, they are ankles and the sea gull is standing on its toes. This form of locomotion is called digitigrade and is also used by cats, dogs and many mammals. Humans are plantigrade (we walk on our whole foot) and horses are unguligrade (walk on their hoofs – analogous to a keratinous nail or claw).
Illustration of plantigrade, digitigrade, and unguligrade. In red the basipod, in violet the metapodia, in yellow the phalanges [toes], in brown the keratin nails. Illustration by Antoine ADAM, see source. [The digitigrade in this illustration is more like a wolf than a gull)
The modified/fused bones in a bird leg and pelvic girdle. Illustration by Darekk2, see source.
Sea gulls have three forward toes and one pointing back (the hallux which is equivalent to our big toe) but it is reduced in size and difficult to see. Their lobation and webbing is called palmate. Some examples of local birds with the four types of webbing: Palmate (gulls), Totipalmate (cormorants), Semipalmated (herons, some plovers and sandpipers), Lobate (black oystercatcher).
Webbing and lobation in a bird’s right foot. Illustration by Darekk2, see source
Gulls are an all around great bird. They are awesome flyers and nimble, quick runners, unlike the waddling Canada goose. And if you ever hear a person described as having “chicken legs”, you know they got it wrong.
Facility work
- cleaned solar panels
- cleaned outside windows on the Keeper’s House
Vessels
- Ecotourism: 12
- Private: 0
Weather
Fresh breeze all day, WNW in the morning backing to WSW by early evening. Skies overcast to cloudy. Daytime temperatures: low 11, high 13.