Aktion Zwerggans e.V. Operation Lesser White-Front Operation Fjällgås
The Lesser White-fronted Goose eggs for our project are collected from breeding farms. At first suitable pairs will be selected to build up a breeding stock. Before a breeding pair can be included in the breeding stock the genetic composition of each individual bird will be tested. According to strict rules of Scandinavian environmental authorities and IUCN (world union for environmental protection) only genetically pure birds should be used for re-introduction. The necessary genetic tests are conducted by most modern genetic methods (analysis of nuclear and mitochondrial DNA) in specialised labs and guarantee that no hybrids of Lesser White-fronted Geese and White-fronted Geese (or other goose species) or birds with an extremely different genetic composition are introduced in the highly threatened remaining breeding population of Fennoscandia. Only birds with an unquestionable genetic composition will be used for breeding and re-introduction The IUCN guidelines for re-introduction recommend that re-introduced birds must be genetically as similar as possible to the original breeding population. As today’s Fennoscandian Lesser White-fronted Goose breeding population has declined dramatically, genetic variety is extremely limited and likely is showing only a small part of the original genetic diversity. According to modern population genetics the critical size for small isolated populations is likely a few hundred individuals. Above this level a population still has the possibility to survive without human help, but below this level such ”bottleneck populations” hardly have a chance to recover again without a strong input of new genetic material.
With a present population size of estimated 100–150 individuals the Fennoscandian sub-population of the Lesser White-fronted Goose is clearly far below the critical level. Although genetic diversity is low, until now regular contacts to the local Russian breeding populations could reduce the negative effects of the small population size. The total Western Palearctic population as well shows a dramatic decrease, which could reduce these contacts and genetic diversity on the short term.
In the scope of this critical situation re-enforcement of the Fennoscandian subpopulation by means of re-introduction with carefully selected birds with a high genetic diversity could be a useful measure.
After the eggs are laid at the end of May / beginning of June, they are taken from the breeding pair and bred artificially in an incubator. Even inside the eggs chicks are able to hear their parents' voices, in this case of their human foster parents. Chicks are imprinted also on the sound of the engines of the microlight aircrafts before hatching in order to make them familiar with. Therefore a tape with the engine sound is played several times a day. By this they get used to it. Shortly before hatching the eggs get transported in mobile incubators to Lapland.
As soon as the chicks have hatched, they recognize their human foster parents. Due to the so-called imprinting, young geese follow their parents (in this case humans) and trust them blindly. This bond is becoming stronger and stronger during the first weeks. When left alone, the chicks get panicked immediately.
From their first day on, the young geese are getting in touch with the microlight aircraft. They see the aircraft, listen to the motor noises (well-known to them from the time before hatching) and soon they are running after the slowly forward moving microlight aircraft.
In the future breeding area the young geese learn from their "goose mum" - the microlight aircraft - how to fly. During flights over the future breeding area, the young geese train their muscles for their long flight to the wintering grounds and learn to know their future breeding habitat. Because young geese regard the grounds where they learn to fly as their future breeding area this process is essential. If everything runs well they will return to this area in the future to breed their own chicks.
In late summer it is time for their flight into Southern grounds. Guided by microlight aircrafts, the young geese fly from Swedish Lapland along the Swedish and Danish coast into Germany and finally arriving at a protected area at the Lower Rhine. This journey is around 3500 up to 4000 km long, depending on the starting place, and demands good condition, stamina and co-ordination both from the young geese and from their human companions. When everything runs smoothly, the mixed groups of humans, microlight aircrafts and geese will arrive at the Bislicher Insel near Xanten at the Lower Rhine about six weeks later.
After their arrival, the contact between the geese and their human foster parents will be reduced step by step. The separation is made easier on them because shortly after their arrival flocks of White-fronted Geese will arrive and the Lesser White-fronts will to join them more and more. Soon they are integrated into the flocks and will fly along with White-fronted Geese to the feeding sites and roosts. In this way the young Lesser Whitefronts learn to know their wintering site and stay here until spring, more or less protected by the big flocks of wintering White-fronted Geese and a hunting ban. Between the beginning and the middle of March, the young Lesser Whitefronts will start heading off towards the Northeast in order to return to their future breeding areas in Lapland - this time however without human company.
After they have found a partner in their second year they will breed for the first time in the age of three years or even later. First breeding successes however are often seen for the first time when geese are four years old. During their first years, the Lesser White-fronted Geese are migrating from their summer grounds into their wintering grounds as non-breeding birds. The migration route is about 3500 up to 4000 km long and usually is taking them about two months (without microlight aircraft company).
© 2001-2007 Aktion Zwerggans e.V.