Friday 22 January 2021

Multi-directional Brent

Another mildish night, perhaps the last for a while, plenty of weak sunshine, but the west wind was surprisingly cold.

Heysham skeer. "Low water" 12:20 (MD)
I'm not keen on neap tides, they occur when the gravitational pull of the sun is at right angles to the pull of the moon, reducing the net gravity on the tides, so they don't come up the shore very far, and they don't go out very far either. Although this can be a frustration to the likes of me, it is much more serious for shore birds that rely on the tide going out far enough to expose their preferred feeding grounds.
I've never seen the Brent feeding at Walney, but it would seem that the access to their normal feeding area is at least restricted on these tides, as this is when the highest numbers come to this side to feed.

I went down onto the skeer at 10:15, this was 4.5 hours after high water, but the inner skeer was still largely covered by water.
Pale-bellied Brent goose at least 34 - the first to arrive were a flock of 4 from the west at 10:20, they landed on the sea in an area that would later become the pool along the drain that feeds the skeer corner. Then 5 minutes later another flock of 5 arrived from the south and landed in the same location. These included the two Canadian colour ringed birds 

At 10:40 a flock of 25 arrived from the north, these landed on the sea to the west, then quickly swam round to join the others in the now formed pool.
This channel they are swimming along is the line of the drain from the pool to the corner. The blue pipe is one of the marker posts that defines the track that dinghy launching tractors follow, almost the same as the drain.

This is a shot of some of the birds feeding in the pool, the early arrivals had to feed while floating.
this includes the Canadian ringed birds, lower centre and left,
 although it's not possible to read them on this shot.
I'm not suggesting that the direction the birds arrived from is the direction they started out from, it either represents different flight lines across the bay, or they have different areas to feed before this area becomes available.
A quick look at 14:30, 2 hours after low water, and there were at still least 32 on the water/mud near the corner, I don't yet know if anyone checked them later out from the play area.

Blackcap 1 male briefly in my garden at lunchtime, I don't get one every winter, but when I do they normally hang around. So hopefully I'll be seeing it again (last winter's bird didn't leave till 18th March).

The feedback I receive about this post is rarely about birds, I'm sure that most of you know much more about birds than I do. But it tends to be comments about things that I see on the shore, it has made me realise that things that I take for granted, would be "news" for anyone who rarely visits the shore, and so it was today.
This is Spume, and really no more remarkable than a pile of autumn leaves after a storm, but it gives me the opportunity to dispel some misunderstandings about it. 
Spume is a purely natural process, it does not suggest any man made contaminants, indeed it is an indicator of a healthy and thriving marine environment.
It was formed by yesterday morning's storm. As the waves break across the Bay, they break up zooplankton and algae into protein chains, which then act as a surfactant, and, just like the surfactants in soap, bubbles are formed. These normally burst quite quickly, but some can last for days. Today's more gentle west wind has blown all the remaining bubbles ashore to form this spume line, which stretched all the way from Half Moon Bay to the skeer. This is just the last 50 m of it.