We must all have seen a cormorant (Phalacrocorax carbo) doing this but why do they do it? Conventional wisdom says it is to dry their wings which obviously get saturated after they have been diving. This may well, of course, be very true but it raises the question that why do cormorants need to do it when other diving birds do not? You never see duck or grebes, for example, drying their wings after a fishing expedition. The answer could well be that the cormorant has much bigger wings and. as it spends more time flying than a duck or a grebe, then drying them out is more important.
I have, however, heard a theory that this posture aids their digestion.
Whilst bladder wrack is the best known of the wrack seaweeds the one most often seen is actually the channelled wrack (Pelvetia canaliculata). Growing freely near the high water line it is adapted to withstand long periods of exposure to the air without drying out. The weed that is out of the water the longest is usually blacker than the paler colour of that which is covered for longer. It does not have bladders for flotation as it rarely needs to float. It may appear to have bladders at the ends of its fronds but the swellings are not full of air, they contain a jelly substance and are the fruiting body of the seaweed. Channelled wrack grows in large masses and can be seen on sea walls, quays and piers as well as the upper reaches of rocky shorelines but each plant only grows to about 18 inches long due to the amount of time it is our of water. It is common around British shores and Dorset is no exception to that. In Scotland it has been used as cattle fodder but I was surprised to r…
The centre of the web is a funnel in which the spider waits. Around the entrance are lots of single strands, a bit like trip wires, that stop insects from an easy escape and gradually bring them nearer to the central funnel from where Agelena can strike!
I have heard people refer to these as Funnel Web Spiders which, of course they are not. Funnel Web Spiders are renowned for being very poisonous where as this spider is quite harmless (to humans).
The are extremely nervous creatures and quickly retreat in to their funnels which makes photographing them very difficult.