Behavioral development in calves

An elephant calf is considered "precocious" in that it can stand up within minutes or a couple of hours at most after birth (by contrast, an "altricial"

offspring is completely helpless at birth). Further, it soon begins walking and following its mother and other elephants in the group. But, this is about the best it can manage in the first few days. The coordination of its limbs is imperfect; it usually stumbles and falls down frequently and needs the support of its mother's trunk and front legs to walk. Its vision is poor, and it finds its mother by smell, touch, and sound. The orientation of suckling is confused. The calf searches for its mother's breasts randomly between her front and her hind legs. During the first week, it has little control over its trunk movements, usually wiggling it about rapidly and even tripping over it.

Much of this changes by the second week of life. The calf's gait is steadier, it can follow or even run short distances with its mother, and trunk maneuverability improves. Vijayakumaran Nair observed Asian elephant calves pick up grass with the trunk tip and objects with the flap of the trunk and the aid of its forelegs by the ninth day, while Cynthia Moss recorded African calves grasping sticks with the tip or the curve of the trunk even earlier. Calves at Amboseli even curiously walked up to a vehicle, inspecting, touching, and even butting it before wandering back to the group. By the end of the first month, the use of the trunk by the calf for manipulating objects improves substantially. It can pick up, hold, and keep in its mouth objects such as grass, leaves, and twigs (fig. 4.1). It cannot, however, suck water into the trunk and drinks directly through the mouth. The calf is essentially still completely dependent on its mother and follows her very closely.

Complete nutritional dependence on the mother continues until the end of the third month. By this time, the trunk maneuverability has improved dramatically. During the fourth month, the calf can pull out grass, herbs, and leaves more easily and, more important, begin consuming them. Around the same time, it begins to use the trunk to suck in water and even transfer some of it into the mouth. It also collects soil and grass with the trunk and throws them on the body. Coordination among lips, trunk, and leg improves; the calf can drop a stick from its lips onto the trunk, step on one end of the stick, and break it. During 3-6 months of age, however, calves continue to suckle at practically the same rate as previously, in addition to some feeding on vegetation, indicating that they need both sources of nutrition for their growth. Nair terms this as an "exploratory period with intense practising" (1989, p. 49).

Independence in feeding quickly picks up between 6 months and a year. By 9 months, the Amboseli calves spent 40% of their time in feeding, with only a small decrease in suckling duration. This is also the period when various actions involving the trunk, feet, and mouth are perfected. The Bandipur calves, for instance, picked up the skill of grasping a bamboo culm, bending it, and standing on it to prevent it from springing back before using its trunk for feeding on the leaves by the seventh month. Later, they even began exhibiting adultlike behavior, such as chasing cattle with spread ears, raised tail, and vocalization. By its first birthday, the elephant calf has developed all the basic skills for independent feeding, drinking, and grooming, although it will con-

Figure 4.1

An African elephant calf trying to grasp a clump of dry grass. A 1-week-old calf can grasp twigs and grass with the tip or curve of the trunk to a limited extent; by the age of 1 month, it can deftly manipulate such objects.

Figure 4.1

An African elephant calf trying to grasp a clump of dry grass. A 1-week-old calf can grasp twigs and grass with the tip or curve of the trunk to a limited extent; by the age of 1 month, it can deftly manipulate such objects.

tinue to depend on its mother for nutrition and defense against predators for at least another year.

Using statistical cluster analysis, Nair looked in detail at the ontogeny of various behavioral elements during the first year in the Bandipur calves. During the first 3 months, the preparatory steps for feeding formed a significant cluster, while those associated with actual consumption of plants were not yet significant. During the 6-9-month period, the two significant clusters were of elements involved in preparation of vegetation and actual consumption of food. By 1 year, of course, the full sequences of feeding, drinking, and grooming are well developed. The ontogeny of behavior relating to feeding is particularly fascinating in elephants. The ability to clean mud from plants by rubbing against the legs, belly, or cheeks or by washing in water and the coordinated use of the forefeet and trunk in uprooting and consuming plants are actions that require considerable skill and discrimination.

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