- Carrying
Capacity- Data Quality and Interpretation
-
Namibia: Caprivi
The Namibian data indicate a resident population in the Caprivi
of the order of 1,000 - 3,000 animals (Table 3).
|
Season
|
Type of survey |
| |
Early Dry (Apr - June) |
|
Late Dry (Jul - Sep) |
Actual Sightings
* Standard Sample Survey
** Total Count
*** Unknown
|
| |
Early Wet (Oct-Dec) |
|
Late Wet (Jan-Mar) |
| Year |
Tsumkwe and Nyae Nyae |
Mahango |
Buffalo Area |
West Caprivi |
East Caprivi |
Mamili |
Mudumu |
Total |
Notes |
| 1977 |
1 |
|
|
|
|
|
|
|
|
| 1978 |
2 |
|
|
|
8 |
|
|
8 |
EC: East of Kabe only |
| 1979 |
2 |
|
|
|
0 |
|
|
0 |
|
| 1980 |
0 |
|
|
|
1,071* |
|
|
1,071 |
|
| |
|
|
|
236*** |
0*** |
621*** |
857 |
In: Rodwell et al (1995) |
| 1981 |
|
|
|
19 |
|
|
|
19 |
|
| 1982 |
|
|
|
|
549** |
|
170 |
719 |
|
| |
|
|
|
150*** |
217***
|
367 |
In: Rodwell et al (1995) |
| 1983 |
|
0 |
|
|
80** |
|
0 |
80 |
|
| 1984 |
40 |
|
|
|
185** |
8** |
0 |
193 |
|
| 1985 |
|
3 |
200*** |
175 |
45** |
228** |
0 |
651 |
In: Rodwell et al (1995) |
| |
|
|
93 |
|
|
|
93 |
WC: Doppies area only |
| 1986 |
|
2 |
|
70 |
74 |
132 |
|
278 |
WC: Doppies area only |
| 1987 |
|
11** |
220 |
250 |
252** |
|
|
733 |
|
| |
|
250*** |
|
|
|
|
250 |
In: Rodwell et al (1995) |
| 1988 |
|
120 |
|
0 |
237 |
|
|
357 |
|
| 7** |
|
|
|
24 |
515 |
|
539 |
EC: St Michel only |
| 1989 |
|
207 |
0 |
7 |
140** |
634** |
|
988 |
|
| 1990 |
0** |
15 |
307 |
|
|
766 |
0 |
1088 |
|
| 1991 |
|
4 |
|
|
|
|
|
4 |
|
| 1992 |
64*
|
64 |
|
| 1993 |
|
4** |
380** |
656** |
|
625** |
0 |
1665 |
|
| 1994 |
|
|
401** |
950** |
|
1173** |
2** |
2526 |
In: Rodwell et al (1995) |
| |
288** |
|
1351 |
|
|
2* |
1641 |
|
| |
|
0* |
|
0* |
3018* |
3018 |
ULG (1994) |
| 1995 |
0* |
2* |
|
|
|
2523* |
2 |
2527 |
|
| 1996 |
|
|
|
|
|
|
|
0 |
|
| 1997 |
|
|
|
|
|
|
|
0 |
|
| 1998 |
0* |
|
33* |
422*
|
103* |
0* |
558* |
|
| 33* |
98* |
|
|
0* |
104* |
324* |
526* |
Craig (1998) |
| 1999 |
|
|
|
|
|
|
|
0 |
|
| 2000 |
0* |
500* |
|
|
|
|
|
500 |
|
| Table 3: Survey results |
Back
to top
Potential carrying capacities for buffalo in the Caprivi
| BUFFALO RANGE |
Area km2 |
Ceiling Density N/sq.km |
Final Buffalo Population |
Rounded Numbers |
Cumulative Population |
Years to reach this level |
| 1. "Core areas" |
5,250 |
2.0 |
10,500 |
10,000 |
10,000 |
25 |
| 2. "Medium Range" |
3,982 |
1.2 |
4,778 |
5,000 |
15,000 |
33 |
| 3. "Maximum Range" |
8,285 |
0.6 |
4,971 |
5,000 |
20,000 |
39 |
The relationship between carrying
capacities and rainfall predicts that under a range of
rainfall from 500-700mm as experienced in the Caprivi (Mendelsohn
and Roberts 1997, p6), buffalo densities at carrying
capacity will lie between 1-2 animals/km2.
The key factors
which will determine buffalo numbers and distribution in the
Caprivi fall largely outside the range of management activities
undertaken within State Protected Areas and depend more on
land use planning and veterinary control measures. Veterinary
control measures impact on buffalo numbers and distribution
and should form the major topic for discussion in bilateral
talks with Botswana on buffalo management.
The exact designation and final boundaries of State Protected
Conservation Areas in the Caprivi (Mendelsohn and Roberts
1997, p7; PW 1998) need to be resolved. Resolution of these
issues will set the base line against which many other land
use and conservation plans can be developed.
back to top
Data Quality and Interpretation
Nothing in the data suggests any marked influx of animals
from Botswana at particular times of the year and this is
unlikely to be demonstrated until a survey is carried out
at the peak of the wet season and a modified
survey technique is devised to overcome the present
difficulty of buffalo
surveys to support more accurate and precise buffalo
population estimates is.
The data is based on the information in DSS (2002a) but has
been updated with additional information from Rodwell (et
al 1995), ULG (1994) and Craig (1998). The following observations
apply to the data:
- The mix of survey techniques (sample surveys, total counts
and actual sightings) preclude comparisons across the full
data set.
- No confidence intervals are given for the sample surveys
in DSS (2002a)and it should be tacitly understood that they
are high (typically + 40-90% of the estimate).
- Despite the apparent plethora of data, there are few complete
surveys of the entire Caprivi in any single year.
- The variation in the strata used within the Caprivi from
survey to survey further reduces the value of comparisons.
Thus caution needs to be exercised in pronouncing apparent
upward or downward trends in populations.
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