Sunday 18 December 2011

Egrets great and small

Picking up on the last post, in which I wondered about the reasons why birds might be found dead on a lighthouse, two bloggers have passed on links to interesting stuff:
http://www.bsc-eoc.org/download/Francis-Jones-light-mortality.pdf reports on photopollution around lighthouses and states that :
Songbirds that migrate at night are attracted to these sources of light, especially under overcast or foggy weather conditions. Birds that are not killed outright by collisions with the light sources can succumb to exhaustion brought upon by prolonged fluttering around a light source or to predation upon individuals in weakened states.

A recent article in Birdguides reports on lights on off-shore vessels attracting an astonishing range of birds including water-rails and bitterns, and well as vast numbers of songbirds, often with fatal results.

And a recent book on British bird observatories reports on collisions at, for example, Bardsey. It is interesting to know that some lighthouses have nearby "safe attraction" lights to lure birds away from the danger, and to a safer landing ground.

On a day-trip to Dungeness to get as far away from shopping malls as possible, I was lucky to see a Grey Heron chasing a Great White Egret around the ARC pit, both landing by the viewing screen. I scuttled around to it and sure enough the Great White was fishing close by - lucky!
LinkIts smaller cousin, the Little Egret, may have been impressed by the size of fish being taken by the Great White, and tried to copy it.
You've bitten off more than you can chew, mate.

In the bright sunshine it's clearly that time again.........
..... which must also be the view of the White Cliffs Ravens which have returned for the third year, and were checking out breeding sites.

Also on the cliffs, having started their season very early, were two Carline Thistle plants in new bud and flower.

1 comment:

Flora said...

I see the Dungeness NNR website (http://www.dungeness-nnr.co.uk/attractions.php) says, about the new lighthouse "This lighthouse is unusual as the whole tower has been floodlit; this has been shown to reduce the bird mortality rate." (And it's mentioned on the Trinity House website http://www.trinityhouse.co.uk/lighthouses/lighthouse_list/dungeness.html)