SOCIAL COOPERATION
Courtesy of Dr. Bruce Hayward
Hunting
Although the mongoose hunts socially, each mongoose is responsible for capturing its own food (Kingdon, 1977). Generally, the entire pack, except for the babysitter, fan out across the habitat digging and turning over items in their search for food. The mongooses travel slowly and remain within seeing or hearing distance of one another in order to ensure that they cover all areas and can react quickly if a member alerts the group of a predator. Hunting in packs is a diurnal adaptation allowing the mongooses to have safety in numbers, especially since they have to travel long distances to find their small prey (Neal, 1970). When banded mongooses forage in large groups, it is difficult for them to find a sufficient number of small vertebrates within their home range. Therefore, they have adapted a dependence on invertebrates as a food source in order to retain the advantages of traveling in large groups while at the same time having an easy to obtain food source with a high biomass. Foraging in groups also allows the mongooses to find food more efficiently and to sometimes obtain food that a single mongoose would not normally be able to get on its own. For example, banded mongooses utilize co-operative bunching to steal prey away from other predators. In addition to aiding the mongoose in foraging, co-operative bunching also helps detect predators, protects young within the middle of the group, and confuses predators by making it difficult for them to single out a mongoose within a closely knit pack (Rood).
Predator Defense
Packs cooperate to provide each other with predator protection. Having a large social group allows the mongooses to take turns babysitting/escorting young and serving as sentinels looking out for predators near the den site. Banded mongooses utilize the “selfish herd effect” to detect and escape from predators. In this method, the increased number of eyes helps detect predators more easily while bunching together in a large group confuses the predator and makes it difficult for the predator to single out an individual mongoose. Rood gives a personal account of a predator-prey interaction that he observed in the field at Serengeti National Park, Tanzania. When a martial eagle captures a banded mongooses, the rest of the group members chase the eagle moving in a close-knit column until the eagle lands on an acacia tree. Once the banded mongooses make their way to the tree, they make threatening sounds at the base of the tree, run up the tree, and finally jump at the eagle, forcing it to drop the captured mongoose. This rescue behavior in banded mongooses demonstrates one reason why living in social groups can be beneficial to the pack. The rescue behavior can be explained by kin selection since members of banded mongoose groups are usually closely related to one another. This type of cooperative behavior can also be beneficial to the group for future purposes. In one case, the rescued mongoose repaid the pack later on when he took on the majority of the babysitting responsibilities (Rood, 1983). Helping in an attack can also ensure individuals that other members in the pack will help them during times of attack when that individual is the one that is the captive.
Care for Young
Another prominent form of cooperation within banded mongoose packs is the communal raising of young. Almost all adult mongooses participate in raising the entire litter of young in the den. They take turns babysitting and form escort relationships with pups. This cooperation is an energetically efficient way of raising young since only one or two members of a group are needed to baby-sit the entire den full of young each time. Escorts guide and teach pups, which increase their survival success.
Overall, all of these forms of social cooperation raise the survival rate of pack members and increases pack fitness.
| General Description | Habitat and Habitat Utilization | Social System | Social Spacing | Social Relationships | Social Cooperation | Summary | References |
* This web site was completed in partial fulfillment of the requirements for Biology 323, Animal Behavior, at Davidson College in the Spring Semester 2005