The colony of swifts that nests in the Museum has been the subject of a research study since May 1948. It is one of the longest continuous studies of a single bird species in the world, and has contributed much to our knowledge of the swift.
What is happening this year?
This year, the first swifts were spotted around the Museum tower on Monday 6th May. Details of nesting pairs and their chicks will be updated week by week through the summer months.
See the statistics for 2018, 2017 and 2016.
The average numbers of young swifts ringed each year over the last 50 years are:
- 1963–72: 36.7
- 1973–82: 70.4
- 1983–92: 100.0
- 1993–2002: 99.2
- 2003–12: 81.1
Swfit diary 2019
- 6 May 2019
They are back! Today we have the first sighting, with a single swift 'patrolling' the tower this morning. The weather is very warm and sunny.
- 7 May 2019
Two more swifts sighted.
- 11 May 2019
One pair of swifts in box E4A (at the back of the tower), weather mild and sunny with no wind
- 13 May 2019
Fourteen swifts sighted around the tower this morning, weather warm and sunny.
- 15 May 2019
Swifts visible on the swift cam in our nests
- 18 May 2019
13 nests occupied. 7 boxes have birds sitting, 5 boxes contain warm eggs but no birds sitting, one box has an adult and 2 eggs. A total of 10 eggs were counted but the other seven boxes may have contained incubating adults. Weather; calm, dry, mild but cloudy.
- 23 May 2019
An egg is visible from the live stream on the swift cam.
- 1st June 2019
Saturday morning 1st June there were 38 active nests with over 40 eggs visible and at least 7 birds sitting tight, probably on eggs too. There are two nests containing 4 eggs although most nests contain the more normal 3 or 2 eggs.
- 8th June 2019
There was a change in the weather this week as an Atlantic Storm rolled in bringing high winds and rain. Today it was cold and wet, windy with total cloud cover, Swifts react badly to this kind of weather and often start ejecting eggs from the nest.
The weather has already provided caualties with one newly hatched chick and three eggs having been ejected from nests.
In cold wet conditions, both eggs and young are capable of entering a state of torpor where body functions are slowed down in a similar manner to animal winter hibernation. This is an adaptation to the variable summer climate in the northern hemisphere.
We still have 36 active nests and two nest boxes that may be used as roosts or are perhaps occupied by first-time breeders. There are at least 44 eggs visible and add to this add 11 hatchlings. A further 9 nests have up to 3 eggs or young hidden under a sitting adult in each so in theory we could have 82 or more eggs this year of which as usual a few may not hatch.
- 15th June 2019
Summer storms and associated cold, windy weather during the critical last week of May and first week of June is always bad news for the swifts in the Oxford colony. We have lost 6 nest attempts, probably by inexperienced birds, due to the weather so only 33 active nests remain but these all seem to be doing well.
There were at least 28 eggs still to hatch and these all had adults in attendance, in addition there are 42 healthy chicks all of which were also being attended by adults.
A change to warm, sunny conditions would really help to bring these eggs and youngsters on and warm, humid conditions should help to provide plenty of insect food for adults and young.
- 22nd June 2019
This week was warm and sunny which has encouraged the swifts, we now have 33 active nests in which 7 eggs and 53 young were visible: these are under-estimates as 21 adults were sitting and many of these hid the nest contents but all will become clear as the young hatch and grow. Most of the visible young are less than 2 weeks old.
- 29th June 2019
Following a hot and humid week with clear skies and little wind, the swifts have been very successful in hatching with only 3 eggs remaining of which 2 were laid during the past week. We now have at least 68 young and 34 active breeding nests. there are a further 7 boxes containing an adult or pair of birds and these may be young birds prospecting for nest sites for next year.
- 7th July 2019
This week has been hot, calm and humid - perfect for swifts. There are 41 boxes occupied and I can count at least 68 young and 3 eggs in the boxes. One of the boxes (E5B) contained a pair of fighting swifts, I separated and ringed these as the fights can go on for hours and can have serious consequences. There are 23 other adults resting in the boxes too, indicating that the young are not hungry. 23 young and 11 adults have today been ringed. Parties of swifts are screaming around the museum tower and all seems well in the world of swifts.
- 13th July 2019
Today is mild and breezy but dry, swifts are active and 39 nest boxes are occupied. A bird is sitting in box E5B where the fight took place so may try to breed. My count today was of 67 young and at least 3 eggs which were being brooded by late breeding adults. Ringing totals are now 36 young and 15 adults. There were 19 adults in residence and two of these were seen to bring food to their young. One youngster has fledged.
- 20th July 2019
We have adopted an orphan! A young swift chick had been found alone with a dead parent and was handed over to us to try and care for. The chick was placed in nest box S5L, which contained only one other chick of approximately the same size and at the same level of development in the hope it would be ‘adopted’ and fed by the adults. Although very thin when it arrived, it seems to have been successfully adopted with the step-parents observed regularly flying in and out of the nest box. It appears to be sufficiently well-fed to be bright eyed, alert and active, as is its new half-brother/sister and hopefully will go from strength to strength and fledge to add to the numbers of swifts from a successful season winging their way back to Africa this September.
They're off, a warm week with recent rain and light winds has prompted another 5 young swifts to fledge bringing the total to 6 birds. My count today was of at least 65 young, there are 36 active nests of which at least 5 contain eggs or tiny young which are not visible due to the adults sitting. Ringing totals are now 69 young and 19 adults with another 4 chicks still too young to ring and a potential 5 or more just hatched in the past week, if the weather remains warm we should easily exceed the total of 72 chicks fledged last year.
27th July 2019
A heatwave this week has been good for the swifts, 36 have now fledged and a further 34 are ready to go within the next few days. There are also 9 very young birds that have yet to grow feathers and at least 4 eggs being incubated. The adopted orphan is still doing well and is almost ready to fledge.
A total of 69 young have been ringed thus far, so the total of hatched chicks is 78 this year with potentially 4 more to hatch taking us to 82 chicks, the highest total for many years and indicating that with care it is possible to grow a colony in size.
Today 24 nests remain active but only 6 adults were present and these were with the youngest birds, whether these young survive to fledge will depend on the weather but if the pattern of warm late summers into September continues as it has for the past few years, then there is every hope that they will make it.
- 3rd August 2019
There are now only 17 chicks remaining, 10 nests and half of these look to be ready for flight. This year 63 chicks have fledged and left for Africa, 9 remain in nests, unringed, so if all survive the total will be 83 chicks fledged. This is starting to approach the pre-2010 totals so it does look as if the colony is recovering.
The good summers have undoubtably helped, clutch sizes have been good and the number of breeding pairs is slowly increasing, 41 pairs attempted to breed this year although not all were successful. It appears that most birds only hatched 2 of the 3 eggs although all but 1 of the hatched chicks survived.
The adopted chick was accepted and did well, both it and its nestmate were ringed and both fledged successfully. This is not the first time we have added a chick to a nest and the added chick has rarely failed to be adopted.
- 8th August 2019
Our Keeper made an extra visit this week as it appeared that one of the swift chicks had been abandoned by its parents. The Keeper moved the chick to a new box with 2 other chicks of approximately the same age. He reports that the chick was in good health and a healthy weight. We are now monitoring the situation to check whether the new chick will be accepted by its new 'parents'.
- 11th August 2019
We still have 6 nests active with 13 chicks remaining. Another chick fledged this week bringing the total of fledged chicks to 67. When all have fledged we will have had 85 chicks, the highest total since 2008.
Four chicks were ringed today, this leaves 4 more to be ringed next week. Adults ringed/identified last year was a total of 20 birds and this years total is the same but there have been 41 nesting attempts so the colony is growing steadily.
The rehomed chick and its nestmates are doing well and the adults are visiting at regular intervals. A spell of warm humid weather would help them and the other remaining chicks to grow large enough to set out for Africa.
- 17th August 2019
Two more swifts fledged this week bringing the fledged total to 69. A further 11 birds remain in 5 active nests and adults are still coming and going with food. The chick that was rehoused on the 8th August is doing well, the adult is feeding it and it is now the same size as its nestmates, they should be ready to leave this week. Growth rate of some chicks has slowed a little due to the cold, wet spell but with warmer, humid weather forcast these young will soon be back up to speed and ready to leave for Africa.
- 23rd August 2019
Today there are only four nests still remaining. The nine chicks are fat and healthy with fully grown feathers. An adult came with food to the box containing three chicks. The forecast is for hot weather over the next week so other birds may well fledge.
- 1st September 2019
Only two nests remain active and just three chicks remain; one of these was doing 'press-ups' in the box so getting ready to leave. This is the chick that was rehoused earlier in the season, as confirmed from its ring number.
- 7th September 2019
Another chick fledged this week so only one nest remains occupied with two large youngsters, we expect them to fledge during the coming week.
- 14 September 2019
They've all gone! The final two swifts left during the past week so 80 chicks were ringed and fledged this year - the best result since 2008. In addition 20 adults were examined and either recorded or ringed.
Much of the credit for this must be given to a warm but humid summer that provided abundant insect food for the swifts, long may this continue. In total 41 nesting attempts were made but only 36 were successful.
Every year we have failed attempts by inexperienced birds but we also have our successes. This year there were ten nests with three chicks, 23 nests with two chicks and four nests with just one chick; we assume these latter to be inexperienced birds. One of the nests with 3 chicks included the orphan that was brought to the museum. It thrived in its new home, was ringed and fledged. The other chick that was taken from its own nest and transferred to a nest with similar aged chicks following concerns from a swift group, was also ringed and following rapid recovery of condition also fledged with its nest mates.
So in conclusion 2019 was a very successful year.