The population status, habitat use and seasonal diet of African elephant (Loxodonta africana) in Majete Wildlife Reserve, Malawi

Forrer, Frances Ann (2017-03)

Thesis (MScConsEcol)--Stellenbosch University, 2017.

Thesis

ENGLISH ABSTRACT: The African elephant (Loxodonta africana) is classified as a keystone species as it is critical to the integrity of the ecosystems it occupies. It influences a variety of factors in these ecosystems that include, but are not limited to, canopy cover, seed dispersal and various plant and animal species distributions. In addition to being classified as mixed feeders, elephants are water-dependent and the location and availability of water affects the extent and intensity at which elephants make use of vegetation. Confinement through the fencing of many elephant populations, particularly in Southern Africa, has adversely affected the management of this species. Population numbers tend to rapidly increase due to improved protection and supplementation of resources, intensifying the species negative effects on other herbivore species. Majete Wildlife Reserve, located in Malawi, was almost entirely devoid of wildlife but was revived by African Parks in 2003. The reserve was fenced, artificial waterholes were installed and an abundance of wildlife was reintroduced, including 213 elephants. Five years post reintroduction, elephant numbers have dramatically increased and concern has been raised regarding the potential impact of this species on the vegetation and other herbivore species in the reserve. In this study, a review of all relevant literature was reported and two field studies were conducted on the population status, habitat use and diet of elephants in the reserve. The population status of the elephants was assessed with aerial survey data and individual identification techniques. The population has increased to an estimated 389 individuals, of which 366 were positively identified. Results revealed a sex ratio of 1:1 and a population growth rate of 13.8% per annum. Additionally, habitat use of the elephants was investigated using camera trap gridlines throughout the reserve. It was determined that a higher number of elephant frequented habitat near perennial water sources and at lower altitudes. Furthermore, waterhole usage was determined using camera traps placed at artificial water sources in Majete. Results suggested that fewer elephants utilised artificial waterholes during the wet season and that family herds tended to dominate the use of the majority of the artificial waterholes. Lastly, it was determined that the use of artificial waterholes was increasingly homogenous in the dry season. The increasing elephant population resulted in dispersal to less preferred areas, namely that of higher altitude miombo woodland as lower altitude regions were potentially becoming too densely populated. Diet of the elephants was investigated using stable isotope analysis of faecal samples to determine seasonal grass and browse composition. Elephants’ diets displayed a clear seasonal difference in the proportion of C3 browse consumed. In the dry season the diet contained 98% C3 browse but decreased to 59% in the early wet season and to 65% in the late wet season. This indicates that a greater proportion of C4 grass was consumed in the wetter seasons, typical of other elephant populations. The results from this study will contribute towards the compilation of an elephant management plan that will be provided to African Parks, Majete, for further implementation.

AFRIKAANSE OPSOMMING: Die Afrika-olifant (Loxodonta africana) word geklassifiseer as ’n hoeksteenspesie omdat dit van kritiese belang is vir die integriteit van die ekosisteme waarin dit voorkom. Dit beïnvloed ’n verskeidenheid faktore in hierdie ekosisteme, insluitend, maar nie beperk tot, lowerdekking, saadverspreiding en die verspreiding van verskeie plant- en dierspesies. Buiten dat hulle as gemengde vreters geklassifiseer word, is olifante afhanklik van water en die ligging en beskikbaarheid van water beïnvloed die mate en intensiteit waartoe olifante van plantegroei gebruik maak. Die inperking van baie olifantbevolkings deur heinings, veral in Suidelike Afrika, het ’n negatiewe effek op die bestuur van die spesie gehad. Bevolkingsgetalle neig om vinnig toe te neem as gevolg van verhoogde beskerming en die aanvulling van hulpbronne, wat die spesies se negatiewe effekte op ander herbivore versterk. Die Majete Wildreservaat, wat in Malawi geleë is, was feitlik gestroop van alle wild, maar is in 2003 deur African Parks herleef. Die reservaat is omhein, kunsmatige watergate is geïnstalleer en ’n oorvloed wild is hervestig, insluitend 213 olifante. Vyf jaar ná die hervestiging het olifantgetalle dramaties toegeneem en kommer is uitgespreek oor die potensiële impak van hierdie spesie op die plantegroei en ander herbivoorspesies in die reservaat. In hierdie studie word verslag gedoen oor die relevante literatuur, asook van twee veldstudies wat onderneem is om die bevolkingstatus, habitatgebruik en dieet van die olifante in die reservaat te ondersoek. Die bevolkingstatus van die olifante is geassesseer deur gebruik te maak van data afkomstig van lugopnames en individuele identifikasietegnieke. Die bevolking het toegeneem tot ’n geskatte 389 individue, waarvan 366 positief geïdentifiseer is. Die resultate toon ’n geslagsverhouding van 1:1 en ’n bevolkingsgroeikoers van 13.8% per jaar. Daarbenewens is die habitatgebruik van die olifante ondersoek met behulp van kamerastrikke op ruitlyne in verskeie plekke in die reservaat. Daar is bepaal dat ’n groter getal olifante die habitat in die nabyheid van standhoudende waterbronne en op laer hoogtes bo seespieël meer dikwels besoek het. Die gebruik van watergate is verder ondersoek met behulp van kamerastrikke in die nabyheid van die kunsmatige waterbronne in Majete. Die resultate stel voor dat minder olifante die kunsmatige waterbronne tydens die nat seisoen gebruik het en dat familietroppe geneig het om die gebruik van die meerderheid kunsmatige watergate te domineer. Laastens is daar bepaal dat die gebruik van kunsmatige watergate toenemend homogeen was in die droë seisoen. Die groeiende olifantbevolking het gelei tot verspreiding na minder gunstige gebiede, veral na die hoërliggende miombo bosland soos die laer geleë streke potensieel te dig bevolk geraak het. Die olifante se dieet is ondersoek met stabiele isotoop analise van mismonsters om die samestelling van seisoenale gras en takvoer te bepaal. Die olifante se diëte het ’n duidelike seisoenale verskil getoon in die proporsie C3 takvoer wat gevreet is. In die droë seisoen het die dieet 98% C3 takvoer bevat, maar dit het afgeneem tot 59% in die vroeë nat seisoen en tot 65% in die laat nat seisoen. Dit dui daarop dat ’n groter proporsie van C4 gras in die natter seisoene gevreet is, wat tipies is van ander olifantbevolkings. Die resultate van hierdie studie sal bydra tot die samestelling van ’n olifantbestuursplan wat aan African Parks, Majete verskaf sal word vir verdere implementering.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/101294
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