Development of social interactions

Apart from contact with its mother for nutrition or otherwise, an elephant calf has the opportunity to interact with several other family members. The rich repertoire and extended period of such interactions help mold the variety of behavioral traits seen in elephants. These interactions could be through suckling, contact by trunk and body, play, aggression, or even merely proximity ("nearest neighbor").

The caretaking of infants by individuals other than the mother is termed allomothering (this does not necessarily imply suckling, for which the specific term allosuckling is used). Phyllis Lee observed at Amboseli that calves are overwhelmingly dependent on their mothers for suckling. In spite of many anecdotal accounts of calves being nursed by their "aunts," instances of allosuckling were less than 4% of all observations at Amboseli. Three-fourths of these few instances of allosuckling were from nulliparous females, while most attempts to suckle from lactating females were terminated quickly. Allosuckling thus seems to be a behavior associated with comforting a calf rather than providing nutrition. The captive Asian elephant calves observed by Vijayakumaran Nair at Bandipur, however, seemed to allosuckle more regularly from females that had weaned their own calves.

Young calves are obviously in proximity to their mothers (fig. 4.4). Amboseli elephants aged 0-8 years remained within 5 m (as measured from scan observations) of their mothers for about 80% of the time. This distance between calves and mothers increased gradually with age, especially in the case of male calves. Distance between calves and nonmother neighbors did not, however, change appreciably. Interestingly, young elephants had at least one neighbor, in addition to the mother, when moving in a group, and these neighbors tended to be closer to the immature elephant than the mother. Female elephants, especially juveniles, were more likely to be neighbors of young calves than expected by chance. This pattern could also partly be an outcome of the association of such females with their mothers, to which calves were attached. When the mother was greater than 5 m away, a calf was more likely to have an age-mate, with the exception of juvenile males, as the nearest neighbor.

When a calf is in distress, as when it has strayed several meters away from the mother/group or got stuck in mud or a hole, it lets out a loud bellow or a deep rumble. Both mothers and allomothers in the group respond quickly by rushing to the calf's side to help it. Vijayakumaran Nair recorded that calves would make distress calls when they strayed more than 5 m away from the mother. Phyllis Lee observed that calves of younger females seemed to make distress calls more frequently.

Figure 4.4

An Asian elephant calf well protected by its mother and an "aunt" within the elephant group at Mudumalai, India.

Figure 4.4

An Asian elephant calf well protected by its mother and an "aunt" within the elephant group at Mudumalai, India.

The direct contacts of young elephants with others include friendly interactions, such as touching the other's body with the trunk, comforting behavior such as rubbing the body against the other, investigating food by putting the trunk into the other's mouth, or interactions relating to play. The Amboseli calves interacted (suckling excluded) with mothers to a slightly lesser extent (2.3 contacts/hour) than they did with all other individuals combined (2.5 contacts/hour), although with any particular age-sex class this was lower (fig. 4.5). As they aged, the male calves interacted at a lower rate with their mothers, but female calves continued their contacts at the same rate.

Interactions of calves can be categorized as those they initiate or receive. Of interactions initiated by calves toward their mothers, the majority were those relating to rubbing or seeking comfort. Those received from the mother were equally likely to be rubbing/comfort or greeting/touching. By contrast, a higher proportion of calf interactions initiated toward and received from others related to greeting. Calves of all ages interacted more frequently than expected by chance with their peers and less than expected with adult females. Interest-

Figure 4.5

The mean hourly rate of interactions of calf with each age-sex class of partners among the young elephants (males and females) observed at Amboseli, Kenya. (From Lee 1987. Reprinted from Animal Behaviour with the permission of Elsevier Science.)

Figure 4.5

The mean hourly rate of interactions of calf with each age-sex class of partners among the young elephants (males and females) observed at Amboseli, Kenya. (From Lee 1987. Reprinted from Animal Behaviour with the permission of Elsevier Science.)

ingly, calves of younger mothers were more likely to receive friendly contacts from others than were calves of middle-aged mothers or matriarchs.

Play is a common behavior among immature elephants (fig. 4.6). Young elephants play by pushing with their heads, wrestling with trunks, mounting or rolling on another (including in water), and chasing. In general, the Ambo-seli elephants tended to play most frequently with age mates. Calves played the most during the first year of life; the bouts of play and time spent in play declined with age (table 4.1). There were gender differences in play behavior. The decline in playing time with age was more pronounced among female calves. By 3 years of age, the males spent about twice as much time in play as the females. Older males also tended to play more with peers of the same sex and also with those less familiar as with peers from other families or social groups. Females were more conservative in that they generally preferred peers more familiar to them, such as within the family or bond group. They were also more likely to direct play toward younger elephants (<2 years old) as compared to males who played with peers of similar age.

All interactions among young elephants and with their elders were not necessarily friendly. Certain behaviors, such as poking with tusks, shoving another away, slapping with the trunk, and chasing or threatening with head and ears shaking were definitely aggressive in intent. The rate of aggressive interactions was very low among young calves, but increased with age, especially in

Figure 4.6

Three African elephant calves indulge in play at Bumi Hills, Zimbabwe.

Figure 4.6

Three African elephant calves indulge in play at Bumi Hills, Zimbabwe.

Table 4.1

Play bouts (as % of all play) among young African elephants of the same sex with all elephants or with strangers, and play bouts (%) of juveniles (>2 years old) directed toward calves (<2 years old).

Same-Sex Play Play with Same-Sex Play with Strangers Calves (<2 years) Total Play

Table 4.1

Play bouts (as % of all play) among young African elephants of the same sex with all elephants or with strangers, and play bouts (%) of juveniles (>2 years old) directed toward calves (<2 years old).

Same-Sex Play Play with Same-Sex Play with Strangers Calves (<2 years) Total Play

Age (years)

with All (%)

(%)

(%)

Bouts Recorded

M

F

M

F

M

F

M

F

0-1

25.5

29.2

3.3

6.2

_

_

153

162

1-2

31.3

33.4

7.B

6.1

_

_

64

66

2-3

3B.6

41.3

6.B

2.2

22.7

45.7

44

46

3-4

45.2

37.2

16.1

3.7

11.3

3B.9

62

54

4-5

67.4

41.7

34.9

16.7

9.3

20.9

43

24

5+

B3.3

41.7

49.4

25.0

2.1

16.7

4B

12

Source: From Lee (1986), reproduced with permission of National Geographic Research and

Lee (1987), reprinted from Animal Behaviour with the permission of Elsevier Science. M and F refer to male and female calves, respectively, while sample sizes (total play bouts) are also given.

Source: From Lee (1986), reproduced with permission of National Geographic Research and

Lee (1987), reprinted from Animal Behaviour with the permission of Elsevier Science. M and F refer to male and female calves, respectively, while sample sizes (total play bouts) are also given.

the case of females. The calves themselves hardly initiated any aggression. Adult elephants, especially males associating temporarily with a group, were the most frequent initiators of aggression toward the young elephants. Significantly, mothers showed more aggression toward their daughters than toward sons. The mere fact that daughters were more likely to be present closer to the mother may explain this observation.

Early behavioral development among elephants thus reflects the needs of the sexes for their eventual role within the social organization of adult society. While mothers may initially invest more in sons because of their greater metabolic needs, the sons become independent from their mothers faster than the daughters, as seen from their increasing distance and fewer interactions. This presumably prepares the young males for dispersal from the family at puberty, several years later. At the same time, young males prefer peers of the same sex for play and are more willing to interact with strangers. These behaviors again would allow them to gain experience for interaction as adults with other males, perhaps in many cases the same age-mates or strangers. Young female elephants, on the other hand, have a more consistent relationship with their mothers. This is to be expected in a species with strong kinship. The proximity of young females to their mothers and the greater likelihood that such females would also play the role of allomothers by assisting calves may have several benefits. Daughters may eventually acquire the social status of their mothers and information about resources that may be crucial in both the short and the long term (when adverse environmental conditions may force elephants to seek resources outside their normal range). This proximity increases competitive interactions between daughters and their mothers, but any costs incurred could be outweighed by long-term benefits.

Was this article helpful?

0 0

Post a comment