Swifts diary

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 20182017 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.
chicks by year




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