Two Willies

I met up with Andy soon after six am. Here at Oakenclough we’d suffered three aborted ringing sessions in previous days. But now a gentle southerly easterly of 5 mph, a break in the clouds with a promise of sunny skies suggested things might improve. Perhaps a spot of Solar Energy might finally erupt in the bleak shadows of the Pennines hills? 

I was hoping to celebrate my birthday of the day before with a few “good” birds, or failing that, a jumbo catch of both warblers and finches, or perhaps a Tree Pipit or two? A search of the Internet on Friday revealed that a good number of warblers, chats and redpolls arrived in coastal locations 12 miles away on both Thursday and Friday as prevailing winds moved to more favourable directions. 

This morning we saw or heard zero pipits or redpolls with just a few Siskins overhead. There was no sign of martins or swallows on the move in what appeared to be ideal conditions for their diurnal migration. It was a very poor catch of just 8 birds - 3 Blackcap, 2 Robin, 2 Willow Warbler and 1 Pied Wagtail. 

Major compensation came in the form of our first Willow Warblers of the year and a “first for the site” in the shape of a fine Pied Wagtail. At first glance the wagtail appeared to be an adult male but closer inspection revealed the presence of some of worn, greyer feathers from its first year plumage, so indicating a second year rather than an adult. 

 Pied Wagtail

Pied Wagtail

The two Willow Warblers caught were both males. We counted seven or eight in song scattered over the entire area but noted that there was no “chasing around”, a sure sign that there are few if any females here yet. Willow Warblers are one of the species where in most years there is a clear time-lag between the spring arrival of males followed a week or more by the females. 

Willow Warbler 

The Willow Warbler is a very numerous species that inhabits extensive parts of northern Europe from the UK in the west to Asia in the east. Willow Warblers breed in Northern Europe and winter in sub-Saharan Africa. 

Over two million pairs of Willow Warblers breed here in the UK and Ireland. That’s three times as many as Swallows, and the same as the next two commonest migrants Chiffchaff and Blackcap combined. Although Willow Warblers are widespread their population, especially in southern Britain, has undergone a moderate decline over the past 25 years making them an Amber List species. 

We caught three female Blackcaps but none of the two or three males in song nearby. 

Male Blackcaps use their black crown feathers in their display to attract a female; the plumage of the latter is much more subdued than the silvery appearance of the male. 

Blackcap 

Studies of the Blackcap in recent decades have proved that substantial numbers of central European birds have taken to wintering in gardens in Great Britain, and, to a lesser extent, Ireland. Previously the Blackcap was just a summer visitor to Britain and Ireland.  

Although the British climate is sub-optimal, compensatory factors include the ready availability of food, (particularly from bird tables), a shorter migration distance, and the avoidance of the Alps and the Sahara Desert in order to return to Africa. 

These wintering birds come from Germany, and isotope analysis of feathers shows that German birds wintering in Britain tend to mate only among themselves and do not usually interbreed with those wintering in the Mediterranean or western Africa. This is because the British migrants arrive back on the breeding grounds earlier than Blackcaps wintering around the Mediterranean, and form pairs before the southern birds arrive.

Linking today to Anni's Birding in Texas.