Friday, 29 July 2016

Bittern

Hello all,
As I promised, here is a post on one of the "Wetland Bird Icon" poll winners-the Bittern.

The Bittern is a member of the Herons and Allies family and have a scientific name of Botaurus stellaris, which references their bull-like appearance and sounds in the first part. Bitterns are on the RSPB's Amber List, and they are of conservation concern. However, it is not all doom and gloom; the overall population of Bitterns in the UK is on the rise.  Here is a distribution map...
Bitterns are a thick-set bird and often look fairly bulky, when you're lucky enough to get a glimpse of one! The Eurasian (or Great) Bittern is the largest member of the Bittern family, measuring in at 69-81 cm in length, 100-130 cm wingspan and weighing 0.87-1.94 kg! The crown and nape are black but the sides of the head and neck are more often a uniform tawny-buff, with black, irregular barring.  Bitterns have a yellowish supercilium and a brownish-black moustachial stripe. The sides of the neck are a rusty-brown and faint barring can just be made out. The chin and throat are buff, with rusty-brown stripes. Meanwhile, the breast and belly are yellowish-buff, with broad stripes of brown at the side and more narrow stripes in the centre. The tail is rusty-buff with black streaks in the centre and black mottling near the edge. The wings are pale rusty-brown, also with irregular barring, streaked and mottled with black. The powerful bill is greenish-yellow with a darker tip to the upper mandible. The eye has a yellow iris and is surrounded by a ring of greenish or bluish bare skin. The legs and feet are a faint, pale green, with some yellow on the feet. Juveniles have similar plumage to adults but are somewhat paler. The feathers on the necks of Bitterns carry the ability to be erected, giving a rather odd silhouette.
Feeding on fish, small mammals and birds, amphibians and insects, the Bittern has a cosmopolitan diet yet requires a special habitat: reed beds. Often, a Bittern is heard and not seen, much like a Cetti's Warbler, really (or Victorian Children as Kate Humble puts it in "Watching Waterbirds")! They live a secretive life, and are best looked for in Winter, when the reeds are thinner and the birds are forced out onto ice to look for food, or in Spring, when males are booming and feeding flights take place. Flushing is a controversial way  of trying to see a bird (don't do it in rare habitat...) but if disturbed, a Bittern often points its bill directly upwards and freezes in that position, causing its cryptic plumage to blend into the surrounding reeds, in an action known as bitterning. While in this position, the shield of long feathers on the throat and breast droop downwards and hide the neck, so that the outline is obscured.

Males are polygamous, sometimes mating with  five females. The nest consists of an untidy platform  30 cm (12 in) across of reeds. The eggs average 52 by 38 mm  and are not glossy but coloured olive-brown, with some darker speckling at the wider end. Four to six eggs are laid in late March and April and incubated by the female for about twenty-six days. After hatching, the chicks spend about two weeks in the nest before leaving to swim amongst the reeds. The female rears them without help from the male, regurgitating food into the nest from her crop, the young seizing her bill and pulling it down. They become fully fledged at about eight weeks.



My experiences of the Bittern
I have only seen a Bittern at one site on one day in my life, and that was at Ham Wall in May. However, by the end of the day, I had begun to ignore the booming, I had got so used to it, but only saw Bitterns about four times, once when they were being chased by Marsh Harriers! WHAT A SIGHT! Absolutely FANTASTIC birds!








Natural England
It is a shame to end on such a miserable note, but it must be shared and the news must be put out there. So-called "Natural" England has announced, in a joint licence with DEFRA, that ten Buzzards are to be culled in certain regions. THIS IS MADNESS. What, pray may I ask, is natural about murdering a native species for the benefit of an invasive and introduced species? Hold on...it isn't even for the benefit of another species! It is, in actual fact, benefiting the gun-wielding madmen who get kicks out of hunting and call it sport as a cover-up! Furthermore, why is the hunting community, a small group of people, being put higher than the birding community, or, in fact, those with common sense! Friends in high places, methinks...
This is yet another ridiculous decision that makes the environmental knowledge of Natural England look laughable. Twitter has exploded with the outrage of those of us who don't support pointless and unfair slaughter, and I'm sure that Natural England will reply with an ambiguous statement that mentions how hard it is working with it partners to make this project sustainable and good for all! Another environmentaly incompetent decision blocks the way to sensible, environmental reforms.

George




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