BLACKCAP warblers were the last summer migrants to leave my garden last autumn. The couple had been with me since late March, and probably reared two broods. They nested a foot off the ground in a bramble bed next to the garage.
When they had gone I found the fragile cage of bent dead grass stems suspended by its basket handles in the bramble bines and lined inside with some fallow and roe deer hair. It had been strengthened throughout by spiders’ webs.
The male with his black cap would often bathe in my old frying pan drinking pool but not when his wife with her brown skullcap was present. She ruled the roost. I think this was their second year in the garden at least by the way they behaved. But it could have been their seventh judging by a report in the Sussex Bird Report.
Bird ringers at Cissbury checked one old bird which was in its eighth year, still wearing the ring put there in 2002. Normally a blackcap could expect two or three years at the most.
Now I wonder where are ‘my’ blackcaps now? I ask myself, because in the past few decades blackcap warblers are being seen in Sussex gardens in midwinter.
The SOS reported 38 individuals in 2008. One was at Bognor Regis eating spindle berries in mid December. Another was eating honeysuckle berries on Christmas Day in Bramber.
But these were not stay-at-home it seems. The British Trust for Ornithology has shown with its ringing programme that blackcaps breeding in Sussex move down south for the winter into France and Spain.
Those that spend their winter in our county are from Norway, Sweden, the Baltic etc so are hardier birds anyway. Several live in Southampton gardens and feed on bird tables in the suburbs. They may sing as they move back north in March before our birds return to sing too.
Many warblers have the habit, like wrens, of cock nest building by the male birds. These are shown to the females as prospective des res in the hope that she will regard him as a suitable husband. She will probably choose one and go on to furnish it with softer materials. The BTO say there are 916,000 breeding territories of blackcaps in Britain. The maximum lifespan recorded was ten years, eight months and fifteen days for an individual.
I have always been intrigued by the way that the young leave the nest quite quickly and have sometimes thought they had been taken by a predator. Apparently the nest-stay date is a mere 11-12 days only. Nests I found as a boy always contained four-five eggs but the limit is seven eggs.
Well it won’t be long now before these lively songsters are back with us again in our gardens, something to look forward to indeed.