Although the difference was less marked for the maximum group sizes, the median group size for the mountainous areas was higher than for the other habitats (Fig.2.4). The forest areas had the greatest spread in tenus of the average and maximum group sizes recorded (Fig. 2.4). Based on habitat area, there were more sightings than expected in the mountainous areas and open tree savanna. In both cases, more sightings than expected were recorded in the mountainous areas and open tree savanna.
Therefore, females raised in mixed groups are more often seen in the more open habitats of montane areas and open tree savanna, where they are present in larger groups. Analysis of the data for adults showed a significant difference between the mean and maximum group size recorded in the four habitats (Table 2.7). When the test was conducted using the habitat area, there were more views than expected in the mountainous areas and open tree savanna (Fig. 2.5).
Note: Critical significance levels were adjusted as data were used in multiple tests (Schork& Remington2000). Adjusted critical P values are:aP=0.007;bP=0.006:CP=0.004;d. Observations were also greater than expected in open tree savanna for all variables except males reared in mixed groups. There were always more sightings than expected in montane areas and open tree savanna (except for males raised in mixed groups).
A surface map showing the distribution of maximum sizes of all-male groups (B) was overlaid with a habitat map (A) to determine the spatial distribution of all-male groups across the KNP (C). For ease of interpretation, only two measures of group size combining habitat and group size (C) were used for the map. In forests in the central KNP, there were more coalitions of males than males, while there were more males in forests in the north and south (C).
This pattern was similar in the open tree savanna and mountainous areas, while there was little difference between the distribution of coalition sizes in the thickets in any area of KNP (C).
HIIIThickets with solitary males
A surface map showing the distribution of observations of exclusively adult males and adult males in mixed groups (B) was overlaid with a habitat map (A) to determine the spatial distribution of observations of adult males in mixed groups compared to observations of exclusively adult males. groups according to KNP (C). For ease of interpretation, only two measures of male observations combining habitat and male observations (C) were used for the map. In all four habitat types, there were several cells in which exclusively adult animals were observed.
Forest areas with only adult males Forest areas with both male group types Mountainous with only adult males Mountainous with both male group types. The surface map showing the distribution of maximum group sizes of adult females in mixed groups (B) was superimposed on the habitat map (A) to determine the spatial distribution of adult females in mixed groups through the KNP (C). In the entire KNP and in all habitat types, there were more groups of females than single females (C).
J 1 till 2-4
I found that group sizes of females in mixed and all-female groups did not differ significantly between habitat types, although there were more observations in the open tree savannah. There was little difference between the overall group sizes recorded in the four habitats, with all four habitats having an average group size of around four. My second test of the RDH was based on the abundance of individual prey species and the influence of each species on the size of the lion group.
I dichotomized for individual lion variables, as these were not independent of total group size. There were nQ significant differences between group sizes of adult males in the mixed groups recorded in the categories of prey biomass Qf or prey biomass tQtal or total biomass less buffalo (Tables 3.4 & 3.5 and Figs 3.2 and 3.3, respectively) . There were positive correlations between wild bee abundance and mean and maximum group size of male Qf reared in mixed groups, but these relationships were not significant (Table 3.6).
Subadult group size was also not correlated with the abundance of any of the seven prey species. Juvenile group size was also not correlated with abundance of any of the seven prey species. The surface map of total lion group size (A) was compared to the impala abundance surface map (B).
The negative correlation between the proportion of available giraffes and the average group size of adult males in mixed group sizes was not significant (Table 3.9). The negative correlation between the available share of kudu and the average group size of adult males in mixed groups was also not significant (Table 3.9). Total group size was not correlated with the availability of any of the seyen prey species.
The group size of all lion variables was largest when killing larger prey species. The areal map of average group size of adult males only (A) was contrasted with the proportions of buffalo (B) and giraffe (D) in the total prey base. The average group size of exclusively adult males (A) was negatively correlated with the proportion of impala (B) and wildebeest (D) in the total prey base.
IiiiiiiIiii~i Figure 3.13. The roebuck proportion abundance map (B) was subtracted from the roebuck proportion kill map (A) to determine areas of higher than expected kill (C). There were very few areas where kills exceeded abundance, probably because impalas are abundant throughout KNP.
3 .0 ,10 III
III 3-4
I have used seven to eight years of data to increase my confidence in the results obtained. In this study, as found in previous studies, wildebeest was important for adult female group dynamics, while impala and buffaio were important for adult males (Rudnai 1974;. However, in terms of functional group, rainfall variability was only important in the wet season and in combined with buffalo abundance, with larger groups occurring in areas of medium variability regardless of buffalo abundance.
In the dry season, there were more groups of females than solitary roosts in more variable environments. Litter size may be influenced by the size of other females in the group, which will then affect overall litter size (Packer & Pusey 1995). Although mechanisms based on single factors used to explain group dynamics are useful in determining which of these factors are important for group dynamics, they often cannot explain all the variance in the data.
For example, ideal free distribution (lFD) assumes that competitors are equal and are free to settle in the optimal area to obtain optimal fitness benefits (Fretwell & Lucas. 1970). Therefore, some groups can settle in the resource-rich areas, while others have no choice but to settle in the resource-poor areas. This is an unrealistic assumption relative to my data, as prey animals move on a temporal basis and may visit the same sites on a daily/weekly/monthly/seasonal basis, resulting in the predators (lions) revisiting the same areas.
Working with KNP data has allowed me to examine the effects of habitat, rainfall and resource patterns and processes on lion group dynamics over a large area and over an eight-year period. While several factors were found to have significant effects on group dynamics in log-linear analyses, their influence on lion group dynamics varied on a spatial scale across KNP. This indicates that although these factors may promote group dynamics in certain areas, their effect may be less pronounced in others due to the interaction effects of multiple environmental elements.
Although lion group dynamics are largely influenced by social interactions, there are environmental patterns and processes that influence the distribution of groups through space and time. Prey abundance, rainfall variability and habitat structure influence lion group dynamics.
CHAPTER SIX
Creation o/index map
The index map provides a reference system that can be used to relate maps with the same dimensions. The maximum female number was determined for each three-month period by superimposing the two maximum female images to produce a map of the total maximum number of females in each cell. In the first step, the absolute maximum number of adult females was calculated for each year of the period.
Since the map of the number of males was divided by the map of the number of females, the maps of females for each period had to be reclassified so that background cells were given a value of −1 (step 2). In the fourth step, the maps of the maximum number of adult males generated in the third step were divided by the corresponding maps of the maximum number of female adults generated in the second step. These maps were reclassified to create the final partition map in step seven (step five).
Where only females were observed, the resulting cell in the final map would have a zero value and where only males were recorded, the cell would reflect a negative number (value divided by -I). The following example shows me the structure of the macro used, this macro refers to data for the period October-December. In the first step, the mJps of maximum pup group size were overlaid with the corresponding reclassified maps of maximum adult:female numbers, as generated in the second step of the adult sex ratio macro (Appendix l.4A). In the second step, the ratio maps of each year \Vere requalified for the final division.
The reclassified maps were :lded (step three) just like the ratio maps (step four), the final product of each step was overlaid to create the final average cub to female ratio map. The databases were opened in the database workshop which resulted in a documentation file being created for each database. The maps of each variable for each period \Vere created and these maps were added and.
The following is an example of the macro age of exclusively adult males, calculated for the three-month period from July to September.
