
Soon the new Fox generation the light of day. While the pups are still largely inactive during the first two weeks of life, they start to become much more lively at the age of three weeks. At the age of one month they appear then before the building. In this time also the first arguments between the siblings begin. Even if these seem playful to us, they have a serious background: The pups prepare themselves for their later life and fight out their position in the family circle. Within a short time a firm hierarchy has formed among them. Physical strength, but also character play a role in this process. Puppies, which are at the bottom of the ranking, often have a very hard time, because they are exposed to the constant attacks of their siblings. These can be so violent that larger wounds are created. By own studies at litter buildings I suspect that a part of the puppies even dies from it. Because the still barely developed immune system has little to oppose the germs penetrating into the wounds – infections have easy game. From the 100 wolled young foxes about 20 do not survive the -first four weeks of life.
In the course of time the pups move further and further away from the burrow. Their short forays take them up to 100 meters away from the burrow by the end of May. In a study by Stiebling (2000), collar transmitters that grow with the animal were used to study the development of young foxes. During these examinations it was shown that the foraging area of the pups has already increased to about 45 hectares in June. At the age of half a year they use about 100 hectares. At this point, only 65 of our 100 puppies are still alive.
Fertile foxes
Reineke is a true reproductive artist: in the same year of life the pups participate in the ranza. After 52 days, the females whelp four to six pups.
The adolescents have almost reached the size of adult foxes in September and the time of migration begins for them. The contact rates among the siblings now decrease significantly, but the hierarchies remain in place. Often the "whipping boys" of the first life weeks are even now at the end of the ranking order. In behavioral-biological investigations it could be determined in this connection that they profit clearly more rarely from fur care with intra-species contacts than further above association members. It is not uncommon for them to still be exposed to aggression from other pack members at this time, which in turn leads to an increased willingness to migrate.
Forced to be nomadic

The better the circumstances, the smaller the foraging territories. Under optimal conditions even fox packs are possible.
How the migration behavior is controlled in the association has recently been investigated in larger fox associations. Those can consist of up to ten adult pieces and the pups. Such fox packs are typical for urban habitats, but can also occur in the countryside. In urban areas, about 20 percent of males and 50 percent of females do not leave their birthplace (Harris& Baker 2009), but join their parents. This has the advantage that they can remain in familiar areas. However, one remains with it also under parental control. As a rule, subordinate foxes are only allowed to use parts of their parents’ territory.
In some of these fox packs, several females reproduce, in some cases even in the same den. Nevertheless, even under such circumstances, a strict hierarchy prevails, which in turn significantly influences the migration behavior. According to a recent British study, which pups migrate from these communal territories is decisively influenced by the dominant female of the pack (Whiteside et a. 2011).
Strict mother regiment
It ensures that their male offspring have to leave the pack, whereas their own female offspring continue to be tolerated. With the pups of the subordinate females the conditions are exactly the other way round. Thus the dominant doe avoids very effectively inbreeding within the pack and increases the chance that one of her daughters (and thus a very closely related animal) will inherit the territory. Also in this point fox females obviously show sense for family.
On the move This is how far foxes run: these factors are crucial
How far foxes migrate depends mainly on two factors: their mortality and the territory size. If the former is high, this usually leads to low emigration distances. And the larger the foraging area, the greater the migration distance.
Males migrate distances equivalent to four to six times the diameter of an average territory (Macdonnald 1990). Thus, urban foxes typically have rather small home ranges (less than 50 hectares). Accordingly, their migration distances are on average only three kilometers. In sparse cleared landscapes with 1.000 hectare territories, they migrate 30 kilometers and more for it. This phenomenon is particularly evident in foxes living at the boundary between two habitat types with different capacities. While those pups that migrate to the more food-rich area tend to cover short distances, those that migrate to the food-poor part tend to walk long distances.
Approximately two thirds of the Rotrocke do not leave its birth place further than five kilometers. Males show the greater willingness to run. Not only do they migrate further, but they also leave earlier. But also females can overcome considerable distances. Such a one could be documented on the basis of a transmitter-monitored piece. This she-fox moved away from the parental territory in December. She undertook a total of 120 kilometers long migration within five days. She ultimately found her territory twelve kilometers from her birthplace (Fiederer 2018). Incidentally, the largest fox migration ever documented was undertaken by a male, which moved -incredible 478 kilometers (Gosselink et al. 2010).
Open country foxes with rough manners
In open-land foxes, contact between siblings breaks down completely in winter (Stiebling 2000). Reaching sexual maturity has now made them competitors. At the end of winter, the last remaining young foxes are told by their parents that they are no longer wanted. Basically, the lower the food availability of a habitat, the greater the pressure that adult foxes exert on their offspring. If there is a lot of grub, the offspring are tolerated longer. In contrast to the city, therefore, in the open country almost all growing foxes have to leave the parental territories.
How the migration process takes place varies greatly from fox to fox. A portion of the pups suddenly set off for faraway places without ever returning home. Another part makes some excursions in different directions before migration. Probably they check the environment for free territories and return thereby however first again and again. Some migratory foxes literally commute between territories before one day they do not return to their home territory. Migration processes take a little more than a month on average. However, very different times can be observed depending on the type. The range is from two to 114 days (Gosselink et al. 2010).
In the spring following birth, an average of 35 of our 100 initial foxes remain. About a quarter of them do not have a home range at this point and continue to wander. The dynamics of this process is illustrated by the fact that after the death of a territorial fox, it takes only about two weeks for the vacated territory to be reoccupied by another fox
Foxes rarely become older than two years

A large proportion of young foxes do not survive the first year of life.
The life of these so-called floaters without a territory is extremely difficult, because foxes live strictly territorially. Even if one is accepted among neighbors and recognizes the boundaries, one is ruthless towards intruding foreign foxes. It is estimated that seven percent of all foxes die as a result of attacks by conspecifics. Hunting, road traffic and diseases are factors that lead to further losses. Only eight animals in our fictitious initial generation live to see their third birthday. Even if the mortality rate of adult foxes decreases significantly, only two foxes out of 100 pups will live to five years of age in the end. Statistically, none of our puppies reach this age. The renowned predator researcher Prof. Michael Stubbe once calculated that under 1.000 foxes only four reach the age of ten years.