WILDLIFE
What’s happening in the blue tit nest box?
by Jane Adams Both sexes look similar, but the male blue tit is considerably brighter, especially in the blue on the head. It is thought that as they get older, they get brighter plumage with each subsequent moult. No other British tit has blue in its plumage. The breeding season varies with location and season, but generally starts in the third week of April. Though blue tits will lay repeat clutches if their first is lost, they rarely try and rear two broods.
Blue tits are on a surprisingly precarious tightrope each spring. Nature writer Jane Adams shares the task ahead of ‘her’ Bonnie and Clyde In March, as I battled with 6ft bamboo canes in weighs in at a whopping one gram. By the time she the overgrown veg patch, two blue tits scolded me finished, she’d laid more than her own body weight from a nearby beech tree. in eggs. Now, she has her bare plucked chest It happens every year: they’ve chosen a nest box (called a brood patch) resting against the eggs to nailed to the side of the potting shed and as incubate them. Any day “the parents will they flit back and forth, they think I’m a bit too now they’ll hatch. close for comfort. If the weather’s good, find more than I’ve named them Bonnie and Clyde and they 15,000 caterpillars both parents will find the look glamorous in their yellow and blue caterpillars needed to feathered coats. They’re living life on the edge in the three weeks appease the appetites of it takes the - their eggs must hatch at the same time as the their hungry chicks. It’s caterpillars they catch to feed their chicks. It’s chicks to fledge” thought that blue tits need all down to timing. to find 100 caterpillars a In April Bonnie built the nest. Starting with a day to feed each chick, and as the youngsters can platform of moss and leaves and finishing by take three weeks to fledge, that’s more than 15,000 wiggling her body to form a nest cup where she caterpillars. placed tiny soft feathers. This month she’s laid an No wonder scientists are worried by the effect egg each day until she has a clutch of ten. Each climate change will have on our native birds’ long-term survival. With spring starting earlier, temperatures rising and rain increasing, will (or can) our birds adapt? For now, I’m keeping an eye on this intrepid pair and hoping they don’t come to a sticky end like their namesakes. The clutch size is highly variable, but usually ranges from 7-13 eggs. Clutches as large as 19 eggs, all laid by the same female, have been recorded.
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Extra Fact File: If you see bees buzzing in and out of your nest boxes, don’t panic. It’s a privilege. They’re likely to be tree bumblebees, and they often nest in bird nest boxes. Treat them with the same respect you would nesting birds. Relish having them in your garden pollinating your plants. Their lifecycle is quick, and they’ll be gone within a couple of months.