Gannet behaviour (1 Viewer)

Greetings seawatchers

I heard a story from a local fisherman recently which I find quite intriguing. Apparently he was shore fishing near Pwllheli last week when he noticed an adult Gannet dropping seaweed into the water from a height then flying down and picking it off the surface, taking it back up several metres and dropping again... and so on.

The bird continued doing this for some time when the chap decided to get back to concentrating on his fishing.

He's at a loss to explain the behaviour - his main idea being that the bird might be using the weed to disturb the water surface and attract fish.

Although I'm aware of seaweed being a component of the nest I have never seen Gannets carrying any away from the breeding areas. The nearest colony is way down in Pembrokeshire so this does not apply here.

Have any of you ever come across or are aware of similar behaviour and do you have any comments on the meaning of this?

Any feedback would be most welcome.

Best wishes

Andrew

I've heard tweo theories on this.

The one that I consider less likely is the idea that the bird is using the seaweed to break up reflections at the waters surface in order to see into the water.

The other is that the bird may be using the seaweed to calculate distance and angle to prey i.e. trigonometry though the bird must also obviously be taking into account altered perception of visual angle from air to water much as some fish do if this is the case.

As far as I'm aware both suggestions are pure conjecture and I've never found any scientific appraisal to back either of them.

Many thanks for the feedback, it would be interesting to know of other observations and theories...

Good Birding

Andrew