Studying Large Carnivores with GPS Technology: Lion Research Project
From the annual report submitted to the Government of Botswana by The Botswana Predator Conservation Program (Dr. J. W. “Tico” McNutt, Director)
Permission to conduct research on lions was granted to BPCP in June 2007. During the second half of the year we identified three different prides inhabiting the core study area that comprises the southern part of Moremi Game Reserve and the adjacent Wildlife Management Areas (WMA). In October 2007, five adults in three different prides were fitted with GPS radio collars (fig. 1). Pride composition is well known for two prides and partially known for the third pride by the end of 2007. The Santawani pride (fig. 1, red and orange dots) consists of 7 adult females, 2 adult males 2 juveniles and 3 recently born cubs. The Gomoti pride (fig. 1, dark blue and light blue dots) consists of 4 adult females, 1 adult male, 3 juveniles and 4 cubs about six to nine months old. The Mogogelo pride (green dots) has 5 adult females, 2 adult males, 2 sub-adults and 7 cubs about six months old.
At this early stage in our lion population monitoring, the data currently in hand are not sufficient to provide reliable estimates of territory sizes and population density. This is due only to the short (three-month) period during which we have collected movement data and observed this subpopulation. Nevertheless, some noteworthy movements are apparent from the dataset to date
- The veterinary “buffalo” fence (in fig. 2) appears to represent an important boundary to the lions in the area, despite the fact we have observed it readily crossed by all carnivore species. Evidence from the recent ranging of the residents on the WMA side of the fence indicates they perceive the veterinary fence to be an important boundary. This either relates to learned risks associated with ranging on the livestock side of the fence, or the possibility that resident lions on the other side of the fence use it as a territory boundary that is observed by lions on both sides.
- Lions’ movement patterns seem to be highly influenced by the movements of conspecifics:
- The female of the Mogogelo pride (fig. 2, green dots), together with another female and their 4 young cubs, seem to be confined within a 20 km. area, squeezed between the wide ranging of the Gomoti male to the west and north (fig. 2, dark blue dots) and the Santawani pride females to the east (fig. 2, orange dots). With the arrival of the rainy season at year’s end, the Santawani pride began moving east (fig. 2, orange arrows) perhaps releasing pressure on their western boundary.
- Two weeks after professional hunters shot his coalition partner (possible brother), the “red” male (formerly the Santawani pride male) was pushed south (fig. 2, red arrow) by a new coalition of two males. Three weeks later he was found dead not more than 30m from the veterinary fence. The cause of death remains unknown following our investigation, but either poisoning or illegal shooting was considered likely.
Figure 2: GPS locations for 5 lions fitted with GPS radio collars in October 2007. A male and a female are collared in the Gomoti pride (dark blue respectively light blue dots). A female is collared in the Mogogelo pride (green dots). A female is collared in the Santawani pride (orange dots). A male from the Santawani pride (red dots) was found dead along the buffalo fence 3 weeks after being collared.