DMC #19: Melodious Migrant
This is the 19th cache of a 20-cache circuit, consisting of 16 new + 4 existing caches adopted from Santos L Helper, which takes you anticlockwise through lovely mixed countryside from near Denton village across to near Middleton hamlet and back.
See DMC #1: Intro & Start for background info on the series, a map (also found in this cache's Gallery) and parking waypoints.
The cache, a screw-topped camo-taped plastic tube, is hidden by a wall meeting the trail heading back towards the start.
As I was making my way towards the eventual cache location I could hear this familiar and unmistakable bird song ringing from tree canopy on the edge of the adjacent woodland (listen here).
The willow warbler (Phylloscopus trochilus) is a very common, widespread, slim and delicate (most common UK) summer visitor (arriving late March-April leaving September) which likes to sing and shake its feathers while it forages for insects. It is strongly migratory, with almost all of the population wintering in Sub-Saharan Africa.
Its scientific name is from Ancient Greek. The genus name Phylloscopus is from phullon (leaf) and skopos (seeker) and the species name trochilus is from trokhilos (wren). Before the English name was standardised to willow warbler by William Yarrell in 1843, it was sometimes called 'willow wren'.
It is unusual as it moults all feathers twice a year - once at its breeding grounds and once at its wintering 
grounds - the reason for this is unclear.
It is a bird of young, open woodlands with trees and ground cover for nesting, especially birch, alder, and willow habitats and often near water. It also inhabits scrub, parks and gardens. It is active during the day, feeding on a variety of small insects and spiders, as well as fruits and berries in the autumn.
Like most Old World warblers (Sylviidae), this insectivorous small passerine is one of the first warblers to return in the spring - though several weeks later than the very similar, closely-related chiffchaff from which it differs by its song and darker legs. Chiffchaffs make a ‘chiff-chaff’ sound while willow warblers have a lovely warble that descends in scale. Its call is quick, happy ‘hewiit’, two syllables, rising in pitch (listen here).
Some 2.4 million UK breeding pairs build distinctive, dome-shaped nests with a hole in the side, in vegetation close to the ground. The 3-9 tiny smooth, glossy white eggs are speckled with reddish-brown eggs are laid in these oven-like nests – 3 eggs weigh the same as 1p coin! The female incubates the eggs by herself for 13 days, but after the young hatch they are fed by both parents, fledging in 13-16 days. There are 1-2 clutches per April-May breeding season. Average life span is 2 years.
See videos here and here.
