Desert Lions

History

Demography

Habitat

Socio-ecology

Behaviour

Dispersal

Dispersal & expansion

Home range expansion
Intensive monitoring of the Hoaruseb lionesses during 2006 produced valuable data on patterns of dispersal and home range expansion. Data collected using a GPS radio-collar and from direct observations (Figure 34) show continuous nightly movements between March and September 2006. Up to April 2006 the lionesses moved only in the Hoaruseb River and in the northern section between the two rivers. During May 2006 they moved to the Hoanib River for the first time and also spent time in the southern and northern sections between the two rivers. In June and July 2006 they returned to the Hoanib River for longer periods, moving quickly between the rivers. On 21 September 2006 the lionesses settled in the Hoanib floodplain and were still there at the end of February 2007 (Figure 35).

Figure 34. Consecutive nocturnal movements of Hoaruseb lionesses between March and September 2006.Click to view enlargement.

April 2006 - 41 days

May 2006 - 37 days

July 2006 - 50 days

September 2006 - 50 days

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Figure 35. A schematic layout of the days, from March 2006 to February 2007, that the Hoaruseb lionesses moved in. and between, the Hoaruseb and Hoanib Rivers. An imaginary line that runs halfway between the two rivers separates the northern and southern sections.
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Habitat expansion
With the rapid growth of the Kunene lion population in the core study area, especially between 2000 and 2004, dispersal of individual lions and the expansion of the range of the population are expected. Intensive monitoring, between 2000 and 2005, of habitat utilisation (Fig. 18) by the core study group of 18 radio-collared lions and their offspring, initiated in 1999, illustrates a striking increase in their range. Reliable estimates of the size of this lion population were calculated, independently of the habitat data, at the end of each year. An analysis of these data show that there is a significant relationship between the number of lions and the size of the habitat they occupy (Fig. 19). Range size can be expressed as a linear function of lion numbers. This finding has important relevance to conservation strategies and when developing human-lion conflict management plans. ** If you have Flash Player watch the animated simulation at the end of this section **

Fig. 18. A schematic layout of the range occupied by Kunene lions, between 2000 and 2005.

2000

2001

2003

2004

2005

Fig. 19. The relationship between lion numbers and the size of the range (km2) they occupied from 2000 - 2005.

 

Dispersal
Dispersal of individual lions, and small groups, is an important mechanism in the ecology and self-regulation of the Kunene lion population. Following a sharp population growth between 2000 and 2004, several individual lions, and some small groups, dispersed from their natal prides in 2004 and 2005, presumably in search for new habitats (Table A7). Radio-collared lions were monitored and 12 incidents of dispersal were recorded. During five events, lions moved deep into unknown territory (N = 176 km, range 92-343) to established new home ranges.

Table A7. Dispersal by 12 lions during 2004 and 2005 in the Kunene Region.

 

Simulated animation of the increase & expansion of the Kunene lions between 1999 and 2006

Last data analysis & update - March 2007