Statistics for 2012
This year the first swifts were spotted around the Museum tower on 28th April. Details of nesting pairs and their chicks will be updated week by week through the summer months.
See below for the week by week diary.
- 28th April 2012
Nestboxes empty - first swifts seen around tower. - 3rd May 2012
All boxes checked - all empty. - 11th May 2012
All boxes checked, fresh droppings in two boxes, many swifts seen around the tower in the evening, some entering boxes briefly for inspection. - 18th May 2012
Only one adult sitting in, and no nests yet, but much activity around the tower. - 27th May 2012
22 nests started, at least four eggs in three nests, 14 adults in nine boxes sitting in, three may be incubating. - 30th May 2012
26 nests started. A thunder storm accompanied by torrential rain meant that 17 boxes had adults in them (26 adults in all). As Swifts sometimes sit on an empty nest and appear to be incubating, or they may be incubating an unknown number of eggs, we cannot be certain how many eggs have been laid so far. Of the 26 adults in the boxes, six appeared to be incubating. However, there are at least 15 eggs in at least 10 nests. Cameras were set up on four nests – three with eggs and one that has not yet laid.
The swifts are showing their usual preference for the top of the tower with 11/16 (69%) boxes occupied there (these were also the first to be occupied), 9/24 (37.5%) on the second floor, 4/24(17%) on the third, none on the fourth and 1/67 (1.5%) at foot level.
- 8th June 2012
26 nests still active. Adults present in 17, of which 13 are incubating. - 15th June 2012
There are still nests in 26 nestboxes, but only 14 have, or might have, eggs (11 nests have 17 eggs, but adults apparently incubating in another three boxes prevented observation of nest content). Three nestboxes have lost eggs since last week. This is one of the worst totals for many years, and largely reflects the poor weather, which keeps adults off the nest for prolonged periods while as they hunt for food. - 18th June 2012
First chicks noted today – three in nest E1a with camera 3, so visible online. Eggshells still in nest. - 20th June 2012
Five broods have hatched. There are now 11 chicks in five nests, and all seems well with them. Eggs are present in another six nests. - 22nd June 2012
One chick in the first brood has died. As the parents are present and it is too young to have starved, we do not know why. - 25th June 2012
Another chick from the first brood taken into care as it wasn’t thriving. - 27th June 2012
There are now nine nests with eggs and/or incubating adults, and five nests with young. There are nine young. - 29th June 2012
Nine young looking good. Camera on nest N5A shows two chicks growing well. - 4th July 2012
One chick has hatched in another nest, giving ten chicks in six nests. All looks fine with these and they are growing well. Eggs are being incubated in a further seven nests and there are still three unhatched eggs in nests where chicks have hatched. There are empty nests in a further 18 nestboxes. A pleasant surprise was that a E7A, which had contained an empty nest for weeks now had an adult incubating two eggs. - 6th July 2012
Ten chicks growing well in six nests and there are 14 eggs in 12 nests although adults only nine of these are clearly being incubated. - 11th July 2012
The ten earlier young continue to thrive and will be large enough to ring soon. Two further eggs hatched in one box (W6B), but one chick died within days. This may be a failure of the parents to brood the young chicks. One new nest has added an egg since last week, but another has lost one so overall there are 12 eggs of which seven are being incubated. - 13th July 2012
The ten large chicks are doing well. Both small chicks in W6B have now died. There are still five nests with eggs (approximately 10 eggs total), three of which are being incubated. - 18th July 2012
Ten chicks doing well and big enough for ringing. There are still a few nests with eggs being incubated. - 20th July 2012
Eight chicks ringed; the other two have already fledged. - 25th July 2012
The eight ringed chicks are all doing well and still in their boxes. Three new chicks have hatched and one nest still has two eggs being incubated. - 3rd August 2012
Of the eight chicks ringed, seven have now fledged, and the eighth should leave shortly. Two other chicks have also fledged (which weren’t accessible for ringing), and there are three remaining chicks in two nests that are not yet old enough to ring – you can see one of these broods on the camera. The two eggs that were still being incubated have sadly been abandoned as the parents know that it is getting too late in the season to fledge young if they continue. - 16th August 2012
The remaining three chicks (in two nests) have now been ringed. - 31st August 2012
All remaining chicks have fledged. This means that only 14 chicks fledged this year, the poorest total for decades. The reason was clearly the weather, with the wettest June on record, which resulted in many birds abandoning their breeding attempts. In all, nests were started in 32 boxes this year, and completed in 28, although some birds then failed to lay, others deserted at the egg stage, and yet some even after chicks had hatched. Although this is disappointing, we need to remember that swifts are long-lived birds, and as such can ‘afford’ to skip breeding in some years in order to improve their own chances of surviving to the following year.
The average numbers of young swifts ringed each year over the last 40 years are:
- 1963-1972 36.7
- 1973-1982 70.4
- 1983-1992 100.0
- 1993-2002 99.2
