Social organisation : the
pack
Wild
dogs have always impressed natural historians with their efficiency as communal
hunters and their highly social behaviour. Wild dogs
communally rear offspring in closely related kin groups known as packs. A pack
is defined in terms of its
potential to reproduce; i.e.; it must include at least one adult male and female.
Occasionally a pack is as small as a single pair, but most are larger, averaging
seven to eight individuals. The pack should be thought of not as a static social
unit but as a group with continuously changing membership. The dogs that originally
form the pack remain constant as long as they survive (secondary emigration
is infrequent), but throughout the year a pack will typically decline in membership
as individuals of various ages who were born into the pack either leave or die.
In the positive direction, every successful year adds a new litter of pups to
the pack.
A
new pack begins when a female or several females from one pack join a male or
several males from another. Usually young females become aware of potential
mates (unknown males) in their area through scent marks left by the males as
if to advertise their presence and availability. These females (usually a couple
of littermate sisters) then leave their natal pack to find the males and attempt
breeding on their own in a new pack. Amazingly, it may take only a day or two
for the males and females to find one another in the vast wilderness ranges
they inhabit. Very soon if not immediately after the formation of a new pack,
the dominant male and female establish themselves in their respective social
positions. The presence of new social partners and potential mates, the incites
the dominants of each sex to actively and aggressively establish or reinforce
their relationships over their siblings-relationships which may have been intact
since early life. These dominant-subordinate relationships are seldom obvious
to an observer prior to the dogs' independence from the natal pack. This is
primarily because wild dog packs are structured on the basis of age class, not
on individual status. However, from the start of a new pack and thereafter,
dominance relationships become reasonably unambiguous and are seldom contested.
Co-operative
care for wild dog pups is one of the most fascinating aspects of the natural
behaviour of wild dogs. In most packs only the dominant male and female breed,
producing a single annual litter. The others forgo their own direct reproduction
and co-operate to care for the young of the dominant pair. Recall that in the
newly formed pack all the females are related to one another and all the males
are related to one another. Therefore, although non-breeders do not have their
own offspring to care for, those that they provision and protect are close relatives
(usually nieces and nephews). From a genetic perspective, each pup successfully
raised increases their own indirect fitness. While
caring for pups at a den, the co-operative nature of wild dogs becomes most
pronounced. The mother of the pups typically remains at the den while the pups
are young. The remainder of the pack will go hunting then return to the den
where several pack members feed the mother of the pups by regurgitating meat.
As the pups get older and start to emerge from the den, they will also beg for
regurgitated meat from the adults. As time passes the hungry mother often leaves
to go hunting with the rest of the pack, sometimes a leaving a self-appointed
'baby-sitter', one of the other adults to remain at the den with the pups. The
responsibility of the baby-sitter is to ensure that the pups remain down the
hole should a predator such as a lion approach. Only after about 14-16 weeks
do the pups begin to accompany the adults when they leave the den.