Nest Boxes for Common Swifts
Common Swifts are cavity breeders. They are present in Germany approximately from late April to August, in individual cases until September. Their nesting sites are legally protected year-round. Common Swifts are synanthropes, meaning they nest in human settlements, often unnoticed. "Naturally" they breed in building niches, which means their natural breeding sites are mainly on tall, old buildings and industrial facilities, as new buildings and those that have been energy-renovated have too few natural openings. They breed in dark cavities in roof eaves, under or behind gutters, in wall holes, under window sills, in leaky roller shutter boxes (with and without roller shutter operation), but also behind facades or roof cladding, for example on flat roofs. Their entrance holes can be very small; they are not always visible from below. They are often only recognized when you observe arrivals and entries in the evening hours. Natural breeding opportunities are dwindling more and more: renovation measures, roof re-covering, so-called pigeon deterrent paste, pigeon spikes and lack of legal knowledge as well as lack of problem awareness make it increasingly difficult for building breeders like Common Swifts to find a nesting site, lay eggs and hatch and raise their young. Common Swifts grow old – the fact that they are no longer there in summer is only noticed when the swifts die and no young have grown up.
Common Swifts are birds that feel comfortable in groups. They would like to fly in flocks and breed in colonies. It is no problem for them and rather an advantage if several nesting sites can be found in spatial proximity. In general: Common Swifts can only be settled where swifts are already flying. After all, they must be able to discover a breeding site.
They prefer dark cavity entrances (no Common Swift, no matter how small, can resist a "cavity"), prefer nest locations with dark cavities and need the possibility of a direct approach. Common Swifts only approach where there are entry possibilities from below or from the front.
Common Swifts approach the nesting site entrance directly from below; there should be an entry height of at least 5 meters.
If you want to newly install nest boxes, you should consider the following.
Basically: To avoid or minimize facade contamination, the entrance holes should be at the front and not under the nest box. The Common Swifts should have at least 5 m distance downward to be able to fly in. Common Swifts should be observable in your residential area. The ideal nesting site is in the east, northeast or north, so that sun exposure in summer is not too high and temperatures in the box remain tolerable. There are many different models available commercially that are tailored to the different possibilities on the house. You can also build a box yourself or specifically create a nesting site in new or renovated buildings.
Artificial nesting sites should not be too small!
Keep in mind that Common Swifts have a wingspan of about 40 cm. They can raise 1 to 3 chicks. Young Common Swifts look out of the nest box and at the world below them. They also do "sit-ups": They press themselves up with the help of their wings and thus train their chest muscles. This means they need a certain amount of space. The fact that Common Swifts today also breed in very small nesting opportunities is also related to the fact that we are taking more and more space from them. Small nesting sites store more heat; young Common Swifts then probably jump out earlier in great heat. So choose spacious nesting aids.
Common Swifts breed in the back part of the cavity corner, so in boxes in the diagonally opposite corner. They prefer simple nests; a nesting hollow of about 1 cm deep and 10 cm in diameter helps to get started. They hardly bring any nesting material into the breeding site, but glue the small nest with materials collected in the air. Please do not place artificial wooden nests in the nest boxes.
Make sure that sparrows and starlings (also specially protected bird species and building breeders) cannot pre-occupy the boxes; they build different nests with different materials and Common Swifts can get caught on the nest materials brought in and strangle themselves. A starling guard is useful here. If you can reach the nesting sites, it makes sense to close the nesting sites in autumn after the birds have departed and only open them again at the end of April. We recommend installing the nesting aids so that they can be reached by you.
It makes sense to open and check the nest boxes after the Common Swifts have departed. Remove all material that is not used by Common Swifts for nest building and fills up the box. Above all, remove plastic, strings, eggs, dead birds. However, no poisons against parasites should be used to clean the nest box. A natural nest of a Common Swift is spartan. They collect exclusively material that is carried to them in the air and glue it with saliva to small, hard nests that are used every year.
This is what natural nests of Common Swifts look like:
Corvids are increasingly specializing in Common Swifts arriving and departing. Make sure that corvids such as magpies cannot land directly on the Common Swift box, for example by using a sloped roof.
Previous recommendations that Common Swift nest aids do not need to be cleaned cannot be maintained. Every year we care for strangled Common Swifts; every year there are reports of nest boxes that are so clogged that Common Swifts can only lay their eggs in the area of the entrance hole; every year there are reports of birds found dead in Common Swift nest boxes from which they could no longer free themselves due to the material brought in. The nesting site shortage for building breeders is great – they now compete for every place, including unsuitable ones.
Together with a woodworking shop, we have developed a nest box for Common Swifts; details can be found here: Nest boxes from JVA Heimsheim
Building instructions can be found on the internet.
Additional nest boxes can also be obtained from Woodworking Shop Sassen.
But: Never simply install ventilation tiles, never simply create an opening for flying in without attaching a nest box behind it! You are thereby turning the space behind this opening into a death trap into which Common Swifts can enter but cannot find their way out.
For new buildings, renovations and energy improvements, with timely planning, you can also specifically replace nesting sites so that they are only visible from outside through the entrance hole. There are special boxes that can be attached under the insulation, but it is also possible, for example, to use special hollow blocks.
If you already have Common Swifts on your building and now want to have the roof re-covered, or carry out a facade renovation or plan an energy improvement, you must consider the following:
Common Swift nesting sites are legally protected year-round. This means that even if you have the work done between September and April (when the Common Swifts are not in Europe), you need a permit (in Hesse: from the Lower Nature Conservation Authority). During the breeding season, such a measure is prohibited anyway. A Common Swift brood is legally protected. Common Swift nesting sites may not be foamed with construction foam, closed with wire baskets, obstructed by scaffolding or destroyed by other measures. In summer, what counts is not an abstract date but the actual presence of Common Swifts. Not all Common Swifts are finished raising their young by the end of July or mid-August!
If you want or need to create replacement quarters, the following should be considered: Common Swifts are extremely site-faithful and very conservative. They use a breeding site for a lifetime and can only adapt with difficulty if it is lost. Breeding pairs fly to exactly their entrance every year. A box that is three meters away will in doubt neither be seen nor noticed by them. Unfortunately, this also means that in doubt they notice too late that the traditional entrance is closed and injure themselves when approaching. Common Swifts fly very fast, even when approaching the nesting site. The approach injuries are correspondingly severe.
An entry option at the place where the entrance was before is ideal. Otherwise, prefer corners and niches that Common Swifts like to accept: Under the roof overhang; at the transition from gutters to rainwater drainage, ...
When choosing the nest box, please orient yourself to the local conditions. Otherwise, what was said above applies.