Blackcaps and Other Birds Visiting Mahonia Flowers

The reports of blackcaps visiting Mahonia flowers caught my curiosity! Although birds visit flowers in many parts of the world for nectar, and also pollinate flowers by their visits, this habit is unexpected in Britain. I dimly recollected reports of blue tits visiting flowers for nectar and on looking up the texts found Susan Fitspatrick's (1994) report of blue tits attacking flowering currant Ribes sanguineum flowers and stealing nectar.She later also reported blue tits visiting Mahonia (1994) Perhaps most interesting was Quentin Kay's (1985) report of blue tits systematically searching pussy willow catkins (Salix caprea and Salix cinerea) and taking nectar. He counted the birds' visits and also analysed the nectar and concluded that it could be a useful source of spring energy and that blue tits were more efficient than bumble bees in the number of florets per catkin visited and the amount of nectar collected. He also concluded that the blue tits and willow interaction was probably the only significant example of pollination by birds in Britain.

To obtain further information Brett Westwood (as Producer at the BBC Radio Natural History Programmes in Bristol), and I were able to include a short description of blackcaps and blue tits taking nectar and possibly pollen in the Radio 4 Spring Watch series in April 1999. This brought in many calls from people who had seen both blackcaps and blue tits visiting Mahonia flowers. Later still, in May 1999, Marianne Wade wrote to me to say she had read in The Daily Telegraph Nature Notes, a book by Robert Burton (1998) in which he said that he had heard from a reader of blackcaps visiting Mahonia flowers and apparently taking stamens. Subsequent publicity in the newspaper brought in over 36 letters on the subject. I have not yet contacted Robert Burton.

I hope more research can be undertaken into blackcaps and Mahonia flowers. How valuable is Mahonia as an energy source to blackcaps? Do they pollinate the flowers? Terry Knight has suggested that the blackcaps going to his Mahonia may be damaging the flowers (they may taken stamens accidentally or on purpose) and reducing the berry crop. Interestingly blackcaps and other Sylvia warblers have been recorded visiting flowers in the Mediterranean winter quarters for nectar, and newly arrived migrants have been found in Britain with their the facial feathers caked with citrus pollen (Ash et al 1961)

I should be very interested to hear of any records of blackcaps visiting flowers and especially of blackcaps and other birds visiting Mahonia. If you have an opportunity next winter to watch very closely and see what the birds actually do to the flowers that would also be of great interest. Also if you have records of blackcaps from last winter which you have not sent in we should still be very pleased to receive them.

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