Saturday, 25 August 2018

keystone brambles support sparrowhawk

Four wonderful days and nights in Dorset watching the satellite tagging of nightjars on Cranford heath. Late nights for an early bird but giving us the chance to see shooting stars that were part of the Perseid meteor shower, noctule bat. During the day we saw dartford warbler and sand lizard. Also, a night of mothing to take my mind off the student fridge that glowered every time I opened it..

Juvenile sparrowhawk
Then home and back to bird ringing in the garden. 
It's been a quiet time of late and this continued despite our early start. 
Our usual 'go to' mist net set beside the feeders unusually provided few birds. It was more encouraging in the area of the garden reclaimed from overcrowded commercial conifers that has now grown high with walls of fruiting brambles beneath silver birch, rowan, field maple and cherry saplings.

This area has become a special place for birds whose presence is frequently concealed by the dense blackberry bushes that now dominate the understory.

Brambles provide year round protection for birds, give thorny defences to nests and this year an abundance of juicy berries as well as being host to many species of invertebrates.

Our bird ringing shows that this jungle provides a home at different times of the year to: 
goldcrest, willow warbler, blackcap and chiffchaff; 
blackbird, robin, song and mistle thrush; 
blue, great, coal and long-tailed tit; 
dunnock; 
bullfinch and chaffinch. 

Great spotted woodpecker, buzzard, jay, woodcock, magpie and treecreeper are there but have avoided the mist nets so far.

A juvenile sparrowhawk showed how important the bramble is as a keystone plant in the food chain. It was hunting the small birds but was caught itself before being ringed and released.

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