Key questions and results
There are three central questions that we looked to address through this study:
1) Feeding habits: Garden bird food seems to be a key ingredient for the survival of UK-wintering Blackcaps. However, we didn't have any data which explored their feeding habits in detail. We found that fat-based foods and sunflower seeds were the two food types that Blackcaps preferred.
2) Male or female? In some species, such as Chaffinch, more females than males migrate to the UK during autumn – males looking to stay as close to their breeding grounds as possible over winter so as to claim the best territories in the spring. We were interested to know if there was a sex bias in the use of gardens by Blackcaps in winter, since this could have pointed towards different migratory patterns of males and females. We found that the majority of participants saw a maximum of one bird in their garden, whether it was male or female.
3) Bolshie bird? Blackcaps have a growing reputation for being grumpy at bird feeders, shooing off other birds that come to feed. But is this reputation justified? We wanted to explore interactions between Blackcaps and other, similar-sized birds at bird feeders. Blue Tits seemed to the birds that were scared off most easily by Blackcaps, and Robin the least likely, but many people saw no aggression at all.
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