Both breeding pairs of Swifts were successful in raising their chicks. But events at the end of the season proved to be interesting so I shall now discuss this in more detail. On the 5 th August, as the light faded, the older of the two nestlings in the front of house box, which was fitted with a camera, spent a lot of time peering out of the nest entrance Fig.
Then, at 9. The second nestling remained in the box being fed by its parents until the 8 th August when it also fledged at dusk. It had a number of abortive visits to the nest entrance where it tilted forward into the hole but then scrambled back, breathing heavily, and then did some wing exercises. But at 9. Our nestlings fledged at dusk whereas Lack and Bromhall both reported that most nestlings in Oxford fledged early in the morning.
Once the nestlings had fledged their parents continued to occupy the box, regularly returning each night. Lack commented that the parents normally remained after their broods have left.
The number of days they stayed was affected by the weather over the summer. Thus, after wet summers, they would stay for an average of between days but one pair stayed for 26 days. However, in fine summers the average was days after their brood fledged. He suggested that they stayed so that they could feed and rest and put on fat to act as a reserve on their long journey south. This fits in with the fact that Swifts leave later after bad summers when food would have been less plentiful both for them and the nestlings they were feeding.
Bromhall also drew attention to the fact that in Oxford the quality of the food available to them decreased at the end of the season. So, meals sampled in July and early August contained very few beetles Coleoptera whereas in one sample obtained at the end of August, out of insects, were beetles. However, in Scotland, particularly in Argyll!
Could it be that, although they are normally found close to the ground, they may possibly be carried up in air currents to the height at which Swifts collect their food and provide more nutritious food later in the season?
It was noticeable in Kilmichael Glassary that when their chicks fledged both of the parents in the box with the camera looked a bit out of condition. Their feathers lacked the sleekness of earlier in the year. But it was worrying that one bird also looked particularly slow in its movements around the box. When in the box there was a lot of mutual preening and wing exercises.
By Krista Charles Swifts time their long-distance flights to catch the best wind Davide D'Amico Small birds like swifts and swallows that migrate long distances have been predicted to travel up to kilometres per day, but new evidence shows that one species of swift can cover far more ground than that.
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They are also loyal to nest sites which they return to for up to 15 years. Swifts produce one brood of two or three eggs each spring, which they lay two or three days apart. This ensures successful fledging of at least one chick as it spreads out the demand for food and allows for insect fluctuations.
Record first swift seen. Swift arrival is usually more predictable than winter departure Photo: North East Wildlife. Swifts are a suitable species as they are found in urban and rural settings and can be easily recognised. We have a lot of records, dating back to , so it is important to collect current first sightings for comparison. Swifts used to be far more common. Their conservation status in the UK has moved from 'Green' to 'Amber' in the last 10 years due to population decline and a reduction in the areas they are found to both breed and over winter in.
A lack of insects their food source , a lack of nesting sites and climate change have all been cited as reasons for swift population numbers and distribution has reduced.
In terms of phenology - the timing of natural events - spring and were both considered to be very early years. This is what we found, across the vast majority of natural events, by collating and analysing your spring records for these years. The phenology events recorded so far in are showing to be, on the whole, a little later, and certainly when compared to these recent early years.
Our live map, which shows records as they come in for each natural event, is a really useful tool for comparing the timing of the same event between years.
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