The patient volume of the Swift Rescue Center (formerly called the "swift station") rose steadily in the early years and levelled off between 500 and 700 swifts per season from 2003 to 2009. In 2010 the 700 mark was passed for the first time. Since then the centre has also been occupied all year round – there is no longer any "end of season" and no "winter break". In 2012 and again in 2013 the 800 mark was clearly exceeded. Since then the figures have settled between 700 and 800 patients a year. This is due to the fact that many severely damaged patients – above all those with plumage damage – require months of intensive treatment at the Swift Rescue Center. When the centre is full and there is "no bed free", no further swifts can be admitted.
The fluctuations from 2003 onwards are due partly to environmental factors that affect the (breeding) behaviour of Common Swifts. In particularly hot years, for example, more young birds jump out of their nest to escape death from heat. Accordingly, more young birds in need of help are found and brought to the centre. The same applies to cold and wet years, although in those years it is severely emaciated birds that are found. In both cases – extreme heat and prolonged rain – the number of insects also drops. Adult as well as juvenile swifts become emaciated. Since 2017 it has been common knowledge that insects are becoming ever scarcer even in good weather. This is due to the use of poisons in agriculture and in allotment gardens just as much as to a largely monocultural agriculture that also seals over farm tracks and tolerates no field margins. Swifts, like other birds, suffer from this too.
In addition, the centre has had to impose temporary admission freezes since 2007, simply because the limits of its capacity were being blown apart. The following graphs show the daily occupancy of the Swift Rescue Center in the years 2018–2021. Although the rearing of uninjured nestlings was partly transferred to competent, carefully selected foster carers in order to cushion peak loads, 2012, for instance, again saw a peak occupancy of more than 250 swifts. The figures for 2013 reflect the fact that the summer of that year was cold and wet. As a result, swifts were often unable to set off immediately after fledging, while new swifts kept arriving at the same time. In 2014, too, peak figures of more than 240 in-house patients were reached. Despite the generous space available, these numbers still demand something closer to complete self-sacrifice than merely a strong commitment from the staff – not least because, with the uncomplicated young birds being "diverted" to foster carers, the patients who remain are the more complicated cases. Adult birds, for example, are always admitted if at all possible, because their treatment as a rule requires special knowledge and skills. Young Common Swifts with plumage damage of the kind that can become apparent once the birds have fledged have to stay with the foster carers until the centre has enough capacity to take them in. Swifts with plumage damage held by private individuals are, where possible, passed on to selected foster carers or admitted directly to the centre.
The tables also show that in recent years each new season has begun with more and more patients still in care. This is due to the fact that the moult of juvenile swift patients only takes place in their second year of life, and that adult Common Swifts only finish their moult in April/May; but there are also swifts that have to wait a very long time before they can be taken in. Such a long stay in human hands can only be justified by the fact that Common Swifts are in principle capable of living for a long time and do not lose their ability to fend for themselves in the wild.
Overview in table form: development of patient numbers 1994–2021
Year | Adults released | Adults died | Adults still in care | Young birds released | Young birds died | Young birds still in care | Total |
|---|---|---|---|---|---|---|---|
1994 | 0 | 1 |
| 6 | 7 |
| 14 |
1995 | 2 | 2 |
| 33 | 17 |
| 54 |
1996 | 9 | 5 |
| 38 | 5 |
| 57 |
1997 | 3 | 8 |
| 71 | 19 |
| 101 |
1998 | 11 | 13 |
| 117 | 22 |
| 163 |
1999 | 27 | 34 |
| 146 | 27 |
| 234 |
2000 | 39 | 31 |
| 251 | 31 |
| 352 |
2001 | 41 | 33 |
| 244 | 44 |
| 362 |
2002 | 56 | 42 |
| 187 | 47 |
| 332 |
2003 | 64 | 69 |
| 317 | 72 |
| 522 |
2004 | 69 | 63 |
| 413 | 71 |
| 616 |
2005 | 66 | 64 |
| 308 | 64 |
| 502 |
2006 | 65 | 57 |
| 439 | 81 |
| 642 |
2007 | 65 | 64 |
| 360 | 87 |
| 576 |
2008 | 58 | 64 |
| 321 | 80 |
| 523 |
2009 | 88 | 79 |
| 420 | 110 |
| 697 |
2010 | 81 | 75 |
| 427 | 138 |
| 721 |
2011 | 75 | 107 |
| 418 | 140 |
| 741 |
2012 | 114 | 128 |
| 437 | 168 |
| 847 |
2013 | 129 | 110 |
| 497 | 120 | 3 | 859 |
2014 | 91 | 109 | 10 | 341 | 107 | 34 | 692 |
2015 | 83 | 70 | 14 | 350 | 136 | 47 | 700 |
2016 | 102 | 90 | 16 | 371 | 97 | 20 | 696 |
2017 | 105 | 101 | 23 | 324 | 140 | 85 | 778 |
2018 | 123 | 134 | 6 | 314 | 155 | 40 | 772 |
2019 | 103 | 113 | 11 | 244 | 143 | 92 | 706 |
2020 | 148 | 145 | 9 | 275 | 171 | 69 | 817 |
2021 | 139 | 136 | 18 | 238 | 114 | 47 | 692 |
The birds brought in come from all over Germany and from other European countries, with a concentration in the Rhine-Main region. In 2021, for example, Common Swifts, Alpine Swifts and Pallid Swifts arrived from Poland, Austria, Romania, Belgium, Italy, France, Spain and Switzerland.
Just under a third of all patients are referred by other institutions, mainly foster carers, animal shelters and vets/veterinary clinics. In most cases, however, the finders turned to the Swift Rescue Center directly.
In 2021 the length of stay of our swift patients that were successfully released averaged 31.4 days (arithmetic mean), with a median of 23 days. The large differences between the arithmetic mean and the median are caused by the long-term patients, who skew the mean upwards. The figure below shows the overall values for all Common Swifts. Looking more closely at adults and juveniles separately reveals that most of the adult swifts released were able to leave the centre after only a short time (14 days), whereas juvenile swifts were cared for for an average of 26 days before release. These figures naturally reflect the rearing period. It is also striking that for adult swifts the decision to euthanise is taken after a median of just 2 days in the centre, while for juvenile swifts it is 14 days. The reason for this is that adult swifts are frequently brought in with extremely severe injuries, so that in many cases there is no chance of saving them. With juvenile swifts, by contrast, the reasons lie elsewhere, for instance in the delayed appearance of damage caused by incorrect feeding at the finder's home. Injuries play a smaller role here, yet in individual juvenile patients the first attempts at flight in the training room do show that they suffered injuries when they fell from the nest which can only now be recognised. The wide discrepancy between the arithmetic mean and the median makes it clear, however, that the decision to euthanise is thoroughly reconsidered and carefully weighed up in every single case. Individual patients with an uncertain prognosis are observed and treated over longer periods, which skews the arithmetic mean upwards.