ABSTRACT
In group living animals, affiliative social interactions maintain cohesion between individuals. Involvement in these interactions is likely to differ between individuals, depending on their sex, age and life history stages. Here we investigated different social network measures to describe greeting interactions within two prides of captive-origin African lions (Panthera leo). We aimed to determine if the introduction of cubs to these prides altered the strength of greeting networks among female lions. We also tested if the strength of greeting interactions changed between the age classes as younger lions matured. We found that interactions amongst female lions decreased from the period before cubs were born (least square means [95% CIs] 15.3 [7.67-22.93]) compared to after their integration into a pride (5.63 [-1.99-13.26] χ21 = 210.03, p < 0.001). In contrast, greeting network strength increased as offspring matured, with adults directing more interactions towards younger lions from 30 months of age (12.89 [1.96-23.82]) compared to when offspring were cubs (-0.69 [-11.63--10.24] χ210 = 156.03, p < 0.001). We suggest that social interactions between age classes may mediate recruitment and dispersal in lion prides.
Subject(s)
Interpersonal Relations , Lions/physiology , Social Networking , Aging/psychology , Animals , Female , Group Processes , Male , Models, Psychological , Sex CharacteristicsABSTRACT
The wild population of the African lion Panthera leo continues to decline, requiring alternate conservation programs to be considered. One such program is ex situ reintroduction. Prior to release, long-term monitoring and assessment of behavior is required to determine whether prides and coalitions behave naturally and are sufficiently adapted to a wild environment. Social network analysis (SNA) can be used to provide insight into how the pride as a whole and individuals within it, function. Our study was conducted upon 2 captive-origin prides who are part of an ex situ reintroduction program, and 1 wild pride of African lion. Social interactions were collected at all occurrence for each pride and categorized into greet, social grooming, play, and aggression. Betweenness centrality showed that offspring in each pride were central to the play network, whereas degree indicated that adults received (indegree) the greatest number of overall social interactions, and the adult males of each pride were least likely to initiate (outdegree) any interactions. Through the assessment of individual centrality and degree values, a social keystone adult female was identified for each pride. Social network results indicated that the 2 captive-origin prides had formed cohesive social units and possessed relationships and behaviors comparable with the wild pride for the studied behaviors. This study provided the first SNA comparison between captive-bred origin and a wild pride of lions, providing valuable information on individual and pride sociality, critical for determining the success of prides within an ex situ reintroduction program.
ABSTRACT
Animal conservation practices include the grouping of captive related and unrelated individuals to form a social structure which is characteristic of that species in the wild. In response to the rapid decline of wild African lion (Panthera leo) populations, an array of conservational strategies have been adopted. Ex situ reintroduction of the African lion requires the construction of socially cohesive pride structures prior to wild release. This pilot study adopted a social network theory approach to quantitatively assess a captive pride's social structure and the relationships between individuals within them. Group composition (who is present in a group) and social interaction data (social licking, greeting, play) was observed and recorded to assess social cohesion within a released semi-wild pride. UCINET and SOCPROG software was utilised to represent and analyse these social networks. Results indicate that the pride is socially cohesive, does not exhibit random associations, and the role of socially influential keystone individuals is important for maintaining social bondedness within a lion pride. These results are potentially informative for the structure of lion prides, in captivity and in the wild, and could have implications for captive and wild-founder reintroductions.
