An assessment to determine habitat selection by large mammals was carried out in South Luangwa National Park, eastern Zambia. We divided Habitat types into five groups based on physiognomic classification as: savannah wood-land, back swamp, Combretum thicket, Mopane woodland, and Terminalia-Erythrophleum. Road count method was used to sight animals across the four identified habitat types. Results showed that puku, impala, elephant, and zebra were highly selective of habitat types. Puku occurred mainly in back swamp habitat (86.6%) followed by water buck (75.0%), elephant (72.3%) and zebra (65.7%). Impala were more abundant in Terminalia-Erythrophleum woodland (69.50%) while buffalo was mainly sighted in Mopane-woodland (45.07%). Other species were more cosmopolitan. It was suggested that foraging behaviour, season and security with respect to predation were the factors singularly or collectively that influenced the observed pattern of habitat selection by large mammals.
A suitable habitat is an important environmental factor affecting the distribution and abundance of wild animals. Choice of a proper habitat determines whether an animal population will survive and grow or not. It is one of the most basic behaviourally mediated processes in an animal’s life and critical for a species long-term survival because it guarantees access to food, water, and cover which are the most important welfare factors [
The study was conducted in South Luangwa National Park (SLNP) which is located between 30.50˚E-32.50˚E and 12.15˚S-14.00˚S in the North-East of Zambia within the Luangwa Valley (
Park. The general elevation ranges from 580 m above sea level at the river bed to
760 m above sea level at the foot of the escarpment. The exact location of the study site was in the Mfuwe area along the Musilashi and Katete streams including the Mbangula and Mfuwe lagoons and areas near Chichele hot spring (
The climate of the area is characterized by three distinct seasons; hot, wet and dry seasons from November to April; cool dry season from May to August and hot dry season from September to early November [
Soils of the South Luangwa National Park have been described in detail by several authors as being varied and are a result of valley formations characterized by the colluvial soil type on the Muchinga escarpment while the reddish-brown terscillitic soil predominates the dissected hilly area [
The general vegetation of the National Park has been well described [
The common plant species on the valley floor include; Diospyros mespiliformis Hochst, Trichilia emetica Vahl, Salix suberrata Wild, Faidherbia (Acacia) albida Delile, Oncoba spinosa Forsk, Kigelia africana (Lam) Benth, Combretum im-
berbe Wawra and Xeroderrisstuhlmanni Taub. The three species Colophosphermum mopane Kirk ex Benth is dominant in the dry shallow sandy and clay soils. Grass species include Echinochloa colona (Linn) Link, Setaria sphacelata (Schumach.) Stapf and Hubbard, Brachiaria brizantha Stapht and Digitaria sp. The vegetation on the escarpment and the hills is dominated by Miombo (Gene- ra; Brachystegia, Julbernardia and Isoberlinia) woodland with common species being Brachystegiaallenii Burtt Davy and Hutch, B. spiciformis Benth, Burkea africana Hook, Julbernardia globiflora (Benth) Troupin [
Habitats were classified according to vegetation physiognomic characteristics as earlier described [
1) Savannah woodland-this habitat occurred on the soils ranging from deep alluvial soils to shallow red soils and the predominat plant species included Faid- herbia (Acacia) albida, Kigelia pinnata, Trichilia emetica, Combretum ghasalense, Securinega virosa, Xeroderris stuhlmannii and Diospyros mespiliformis. Grass species were mostly Hyparrhenia rufa (Nees) Stapf, Andropogon sp. Linn. and Cymbopogon excavates (Hochst) Stapt.
2) Back swamp-this habitat type is subjected to seasonal flooding during high flood peaks and is mainly associated with lagoons, swales and levees of the main river channel. Soils are deep alluvial types which support plant species characterized by Echnochloa colona, E. Pyramidalis (Lam), Setaria sphacelata, Phragmi- tes mauritianus Kunth., and the main tree species include Combretumimberbe, Faidherbia (Acacia) albida, Onchoba spinosa, Salix subserrata, and phyllanthus reticulates Poir).
3) Combretum thicket-this habitat occurs on dry red soils, and comprises plant species such as Combretum obovatum F. Hoffin, C. elaeagnoides Klotzsch, Dichrostachys africana Brenaand Brummit, D, cinerea L) WeighandArn, Diospyros senensis Klotzsch, Markhamia sp. Seem.exBaillon, Schrebera tricholada Wehv, Cassia abbreviata Oliverand Capparis tomentosa La, which is mainly associated with termite mounds.
4) Mopane woodland this is the major habitat type on the river valley floor, supported by valley sandy soils on high ground and by clay soils in lower areas. The main plant species are Colophospermum mopane, Ximenia, americana L., Combretum obovatum, Euphorbia sp., Balanites aegytiaca, Commiphora sp., and Capparis tomentosa.
5) Terminalia Erythrophleum this habitat is limited in occurrence and is ma- inly confined to sandy soils. Characteristic plant species include Terminalia sericea, Erythrophleum africanum Markhamia occuminata, Cassia abbreviata, and common grasses are, Andropogon sp., and Hyparrehenia sp.
We estimated the distribution of large mammal species by using the Road Strip Census Method earlier described [
Habitat selection was evaluated based on the following; 1) habitat preference which was defined as density of a species in habitat by total density of species [
Results showed that puku had very high presence in back swamp habitat (86.6%) followed by water buck (75.0%), elephant (72.3%) and zebra (65.7%) on the same habitat (
Mopane woodlands (11.70%), while buffalo were mostly encountered in Mopane- woodland (45.07%) (
Densities of species in each of the habitats are given in
The most preferred habitat type was the back-swamp with puku recording the highest (76.33%), followed by water buck 75.02%, elephant 72.15% and zebra 65.66% (
Species | Combretum thicket | Woodland savanna | Back swamp | Mopane Woodland | Terminalia-Erythrophleum |
---|---|---|---|---|---|
Buffalo | 8.90 | 0.00 | 0.00 | 12.40 | 6.90 |
Elephant | 1.90 | 10.80 | 64.50 | 4.50 | 7.70 |
Impala | 54.8 | 2.70 | 27.40 | 0.90 | 315.10 |
Puku | 0.39 | 32.00 | 276.40 | 53.30 | 0.00 |
Water buck | 0.39 | 1.50 | 32.40 | 8.90 | 0.00 |
Zebra | 8.90 | 0.00 | 43.60 | 10.40 | 3.50 |
Species | Habitat type | ||||
---|---|---|---|---|---|
Combretum thicket | Woodland savanna | Back swamp | Mopane Woodland | Terminalia-Erythrophleum | |
Buffalo | 29.58 | 00.00 | 00.00 | 45.07 | 25.35 |
Elephant | 02.16 | 12.12 | 72.30 | 04.76 | 08.66 |
Impala | 12.10 | 00.60 | 06.00 | 11.70 | 69.50 |
Puku | 00.12 | 10.00 | 86.60 | 03.26 | 00.00 |
Water buck | 00.89 | 03.57 | 75.00 | 20.54 | 00.00 |
Zebra | 13.40 | 00.00 | 65.70 | 15.70 | 05.23 |
Species | Combretum Thicket | Woodland Savanna | Back Swamp | Mopane Woodland | Terminalia-Erythrophleum |
---|---|---|---|---|---|
Buffalo | 31.56 | 00.00 | 00.00 | 43.42 | 24.47 |
Elephant | 02.12 | 12.08 | 72.15 | 05.03 | 08.61 |
Impala | 13.67 | 00.67 | 06.83 | 00.22 | 78.60 |
Puku | 00.11 | 08.84 | 76.33 | 14.72 | 00.00 |
Water buck | 00.90 | 03.47 | 75.02 | 20.60 | 00.00 |
Zebra | 13.40 | 00.00 | 65.66 | 15.66 | 05.25 |
with 6.0% and 0.6% respectively. Buffalo did not show preference for woodland- savanna and back-swamp habitats, but Mopane-woodland 45.07% followed by Combretum-thicket 29.58% and Terminalia-Erythrophleum 25.35% (
Species distributions, habitat preference and affinity for each habitat were tested using Chi-Square (χ2) [
Species | Combretum thicket | Woodland savanna | Back swamp | Mopane Woodland | Terminalia-Erythrophleum |
---|---|---|---|---|---|
Buffalo | 0.86 | 0.00 | 00.00 | 1.26 | 0.72 |
Elephant | 0.52 | 2.90 | 16.60 | 1.14 | 2.08 |
Impala | 0.92 | 0.05 | 00.46 | 0.90 | 5.33 |
Puku | 0.03 | 2.17 | 18.22 | 0.70 | 0.00 |
Water buck | 1.00 | 0.19 | 04.12 | 1.10 | 0.00 |
Zebra | 0.93 | 0.00 | 04.56 | 1.07 | 0.35 |
Species | χ2 values based on proportions | χ2 values based on habitat preference | χ2 values based on Affinity Index |
---|---|---|---|
Buffalo | 37.44 | 74.03 | 1.03 |
Elephant | 173.81 | 172.79 | 39.10* |
Impala | 35.13 | 220.82 | 12.11 |
Puku | 240.86 | 206.04 | 54.54* |
Water buck | 183.01 | 203.28 | 7.31 |
Zebra | 118.42 | 138.51 | 8.33 |
Significant at α = 0.05 with df = 4 Significant at α = 0.01 with df = 4 χ2 0.05, 4 = 9.4877 χ2 0.01 = 13.086.
Habitat selection is viewed as a hierarchical process involving innate and learned behaviourin which an individual decides what habitat it prefers [
Previous studies have shown that waterbuck generally a riparian species usua- lly occurs in woodland along streams, rivers or dambos [
Similarly, reasons are not clear for the lack of selection of woodland-savanna habitat by zebra as the species occurs in plains and dambos and in light woodland or mixed savanna [
Impala is largely a browser and an occasional grazer, therefore, it would be expected to have high selection for wooded vegetation where there was adequate browsing material. As Tables 1-3 show, suitable habitats for the species were mainly Terminalia-Erythrophleum, Combretum-thicket and Mopane woodland during the wet season as given in the percent habitat preference and Affinity Index values. The lack of selection for woodland savanna and back swamp suggests that this would be due to the species’ browsing habits and a possible indication of poor vegetation structure of the two habitats to provide a suitable and within reach browse for the species. Recent studies on distribution and habitat selection of the species [
Although there was no significant statistical difference when the Affinity Index values were used in the manner in which buffalo selected its habitats, the species’ presence in Mopane woodlands, Combretum-thicket and Terminalia- Erythrophleum was indicative of the relative preference for these habitats. As for, buffalo it is known that they are generally gregarious and show very active day movements covering wide distances [
Both elephant and puku were the only species that showed a statistical significance when affinity values were tested using Chi Square Test for their affinity for the back-swamp habitat. Our views on this matter might be conjectural but probable. Puku is generally described as a wetland species usually inhabiting dambos, marshy areas and flood plains [
Elephants are bulky feeders and results show that they occurred in every habi- tat. However, the high values for habitat preference for back-swamp and woodland-savanna and equally high values of Affinity Index for the same habitats would signify the predominance of grazing habits by the species during this time of the year. Earlier investigations [
Studies on habitat selection tend to point on several aspects that might require serious consideration in wildlife and protected area conservation. Critics have maintained that while there are variations and limitations in research methologies in data collection and data analysis involving habitat selection, studies have tended to oversimplify the habitat selection theory. This concern has been raised in some discussions [
Chabwela, H., Chomba, C., Kaweche, G. and Mwenya, A. (2017) Habitat Selection by Large Mammals in South Luangwa National Park, Zambia. Open Journal of Ecology, 7, 179-192. https://doi.org/10.4236/oje.2017.73013