Guidelines for Placing Swifts in Foster Nests

Translation from www.bristolswifts.co.uk

These guidelines are intended for people who have experience with swift nest boxes and are familiar with swift behavior. Swift fostering should only be carried out by those who feel sufficiently competent to do so. It is also recommended to use only nest boxes with cameras.

Swift fostering is the process of using a nesting pair of swifts to rear chicks or eggs. There are several situations, for example:
● Placing an abandoned egg into a nest with no more than 2 eggs of a similar laying date.
● Placing an abandoned chick into a nest with no more than 2 chicks of a similar age. This may include placing 2 chicks into a nest with 1 chick of a similar age.
● Placing a chick from a brood of 3 chicks if one parent has disappeared.
● Placing a swift chick that has fallen to the ground into a nest with no more than 2 chicks of the same or similar age.

Compared with rehabilitating swifts, rearing them in a foster nest takes less time and money, and it is obvious that swifts themselves are the best parents.

Target nest

First make sure that both parents are visiting the foster nest.
It is better to choose a nest that can be observed, ideally one with a camera in the nest box. If there is no camera, carry out periodic checks over the next few hours after placing the chick.
Successful rearing in a foster nest is also possible without constant observation.
Nests with one chick are preferable, but nests with two chicks are also acceptable.

Relative size of the chicks

The sizes of the chicks should be as close as possible, but they do not have to be identical. Chicks placed into the nest that are smaller or larger than the existing chicks may still be successfully accepted, but the size difference should be small. Visually compare the length of the developing wing and tail feathers.

Absence of one parent

This is usually discovered when only one parent returns to the nest at night. In that case, the second parent may return early the next morning. If it does not appear during the following day, a foster nest should be sought on the second day of absence.
If one parent disappears, the remaining parent is usually capable of raising one chick, and in most cases two as well. This may depend on the weather.
If a parent disappears from a nest with 3 chicks, one or more chicks should be moved for fostering or rehabilitation.
If both parents disappear, all chicks need rehabilitation or rearing in a foster nest.
Fostering should be carried out as soon as possible after the parent disappears.

Small chicks

Sometimes one chick hatches later than its siblings and is much smaller. Such chicks cannot compete, and their chances of survival are lower. They may be helped by placing them in a nest with chicks of a similar size. Alternatively, the larger chicks can be moved if a more suitable size match can be found.

Swift fallen to the ground

The only path to saving a swift that has ended up on the ground, whether an adult or a bird injured in an accident, is recovery under the supervision of a specialist who knows how to do this properly. This requires specific skills. To understand whether a swift can fly, raise it on your palm as high as possible and simply hold it there. Never throw it into the air. If it is ready for flight, it will take off on its own.

Unlike chicks transferred from an active nest, it is almost impossible to tell how long a swift found on the ground has been there. Therefore, the first thing to do is assess its condition: it may be dehydrated or emaciated. It is best if this is done by a qualified specialist or an experienced person.

A swift in good condition should:
- Look at you with clear, lively eyes (provided they should be open at its age) - Have a breastbone (keel) that does not protrude sharply, which is a sign of good nutrition. - Move symmetrically. - Be able to lift its head. - Have a weight appropriate for its size. - Not be dehydrated; this can sometimes show as pallor inside the mouth.

If there is any doubt, and if observation is not possible, the swift should be handed over to an experienced rehabilitator. In the meantime, it is important to maintain the bird's hydration until a foster nest or rehabilitator is found.

Determining a swift's age

A young swift has white edges on the wing feathers, throat, and forehead, which makes it look scaly. An adult swift has a white patch only on the chin.

Sensible fostering proportions

• One chick can be placed into a nest where there is already one chick; this is the best situation.
• Placing one chick with two chicks is also acceptable; swifts often rear 3 chicks.
• Placing two chicks with one chick can also work.
• There are known cases of successful rearing in a foster nest when a fourth chick was added to three chicks. Since swifts rarely have a brood of 4 chicks, this should only be done in an emergency and only in favorable weather.

Weather conditions

Swifts struggle in bad weather, so the decision to leave two chicks with one parent may depend on the forecast. Similarly, placing one chick with two chicks in bad weather should be avoided if there is an option to place one chick with one chick.

When and how best to place a chick

It is preferable to place a chick when the adult birds are not in the nest. After a certain age, the parents are absent most of the time anyway. If the chicks are still small, this may not be the case, and in that situation try placing the chick under the sitting adult. If the adult swift flies out of the box, it is unlikely to abandon the nest at this stage of the cycle.

Observation

A camera in the nest box is the best way to observe, but if there is no camera, check the box a few hours after placing the chick to make sure everything is fine.

"Jumper" chicks

Some swift chicks may persistently jump out of the nest box soon after being placed there. This is not a common enough problem to rule out this approach, but if the foster chick disappears soon after placement and is found below the nest, its only chance of survival is rehabilitation.

Placing eggs

Sometimes adult swifts abandon their eggs. Eggs can survive without incubation for up to 8 hours. If the laying dates are known and there is a potential foster nest where the eggs were laid within 1 day of the abandoned nest, you can try placing 1 egg into a foster nest with 1 or 2 eggs. Check whether the egg is fertile by candling it with a narrow beam of light.
If the laying dates are unknown, do not attempt this.

Rehabilitation

For guidance on dealing with a grounded swift that cannot fly, start here and follow the links. This includes notes on rehydration:
actionforswifts.co.uk/p/grounded-swift.html

Acknowledgements

People who have shared their experience of successful rearing in foster nests include Mark Smyth, Mark Glanville, Louise Bentley, Tanya Hoare, Lynda Huxley, Bernard Genton, and Marcel Jacquat.