Aspekte rakende die ruimtelike ekologie van die rooijakkals (Canis mesomelas) as probleemdier in die Suid-Vrystaat - Deacon, Francois (University of the Free State, 2010)
According to the Red Meat Producers’ Organisation, damage-causing predators annually catch small stock to a value of approximately R1,1 billion in South Africa. On most of the small stock farms in the Southern Free State, black-backed jackals, Canis mesomelas, are shot on sight and actively hunted to provide a safe environment for domesticated animals. The veld and habitats previously occupied by natural prey for these carnivores are now used for commercial farming practices. Carnivores are conserved in established formal protection and conservation areas within the ecosystem to lessen their contact with small stock. In South Africa the black-backed jackal successfully adapts to this farming environment with visible adaptation patterns. These behavioural patterns are influenced by the circumstances of the animal and variables within its environment. In the study area these fixed patterns of the black-backed jackal presumably annually repeat itself. This study researched these behavioural patterns of the jackal. For the first time, geographic information systems (GIS) are used in the research of the black-backed jackal. Since 2006, black-backed jackal regional data (of all jackals killed during hunting operations) was collected in a high depredation area in the Southern Free State. Data points collected from 1927 to 2009 were accordingly entered on electronic charts in ArcView. The total number of data points were obtained from 433 black-backed jackals killed, with the localities of 344 charted. The data is grouped into four sets: the first set, collected over 26 years, 1927 to 1953, consisted of 15 black-backed jackals; the second set, collected over 5 years, 1993 to 1997, consisted of 124 black-backed jackals; the third set, collected from 1999 to 2008, 10 years, consisted of 210 black-backed jackals; and the fourth set, from 2006 to 2009, four years, had a total of 84 black-backed jackals. Therefore, the number of black-backed jackals killed significantly increased, from 15 killed the first 26 years, to 418 over the last 16 years, within the same specific area. The increase in numbers of black-backed jackals removed from the area is used as indication of the increase in damage over the years in the study area. The average mass of 68 males, killed between 1993 and 1997, was 7.15kg and 63 females, 6.72kg. According to the 35 farmers in this specific area of the Southern Free State, the jackal problem is at present more under control than 30 years ago, which also applies to some other parts of the Southern Free State and South Africa. The reason for this can be ascribed to a better understanding of the animals and planning of hunting expeditions. In the late 1980’s, the average loss per farmer was ± 200 sheep per annum. At present, about 40 sheep on average are lost per farmer. The aim of this study is to further alleviate the damage-causing problem in the study area by making accurate predictions and planning to decrease losses. In the study area, peak losses are noted annually from August to October and March to May. The black-backed jackals mainly follow certain fixed movement patterns in the study area and breeding pairs seemingly react to the same stimuli from their direct environment. The same dens are repeatedly used and there is a clear relationship between the location of the dens and human activities. When a breeding pair is removed from an area, a new breeding pair will soon establish there. The processing of historic data leads to predictions on where the black-backed jackals will establish, where they will breed and where they will probably cause damage. It also predicts where they can probably be caught. This study shows a strong correlation between the physical nature of the environment and the black-backed jackals.

Die Rooivleis Produsente Organisasie (RPO) bereken dat skade-veroorsakende diere jaarliks kleinvee ter waarde van nagenoeg R1.1 miljard in Suid-Afrika vang. Op die meeste kleinveeplase in die Suid-Vrystaat word rooijakkals Canis mesomelas tans in die algemeen op sig geskiet en aktief gejag om ‘n veiliger plek vir gedomestikeerde diere te verseker. Veld en habitatte wat voorheen slegs beset is deur natuurlike prooi vir hierdie roofdiere word nou benodig vir kommersiële boerderypraktyke. Formele beskermings- en bewaringsareas is gestig binne die ekosisteem waar roofdiere bewaar kan word en kontak met kleinvee kan verminder. In Suider-Afrika kon die rooijakkals egter ook suksesvol aanpas in die boerderyomgewing en aanpassings-patrone is sigbaar. Hierdie gedragspatrone word beïnvloed deur die omstandighede van die dier en veranderlikes binne sy omgewing. Daar word gereken dat die vasgestelde patrone van rooijakkalse in die studie-area hulself herhaal van jaar tot jaar. Hierdie studie bestudeer van hierdie gedragspatrone van die rooijakkals. Dit is waarskynlik uniek in die opsig dat geografiese inligting stelsels (GIS) hier vir die eerste keer ingespan word in die navorsing van rooijakkalse. Sedert 2006 is rooijakkals lokaliteitsdata (waar alle jakkalse gedood is tydens jagoperasies) versamel in ‘n hoë predasiegebied in die Suid-Vrystaat. Datapunte is hiervolgens aangeteken op elektroniese kaarte in ArcView. Datapunte vanuit die gebied is akkuraat aangeteken vanaf 1927 en bygewerk tot 2009. Die totale hoeveelheid datapunte is afkomstig van 433 rooijakkalse gedood, waarvan 344 lokaliteite op kaarte aangebring kon word. Vier stelle data kan onderskei word: die eerste stel, versamel oor die 26 jaar 1927 tot 1953, bestaan uit 15 rooijakkalse; die tweede stel, versamel oor die 5 jaar 1993 tot 1997 (inligting ontbreek vir 1998), bestaan uit 124 rooijakkalse; die derde stel, versamel van 1999 tot 2008 (tien jaar), bestaan uit 210 rooijakkalse; en die vierde stel, van 2006 tot 2009 (vier jaar), het ‘n totaal van 84 rooijakkalse. Die oorvleueling van 2008 en 2009 is as gevolg van twee stelle aantekeninge deur twee veskillende jagters in dieselfde gebied. Die aantal rooijakkalse gedood het dus aansienlik toegeneem: van 15 gedood oor die eerste 26 jaar, tot 418 oor die laaste 16 jaar; alles binne dieselfde spesifieke gebied, en waarskynlik met dieselfde akkuraatheid aangeteken (M. le Roux, pers. komm.). Die toename in rooijakkalse wat uit die omgewing verwyder is, word as indikasie gebruik dat skade ook oor jare in die studiegebied vermeerder het. Die gemiddelde massas van 68 reuns en 63 tewe gedood vir die tydperk 1993 tot 1997 was 7.15kg en 6.72kg onderskeidelik. Volgens die 35 boere in hierdie spesifieke deel van die Suid-Vrystaat is die jakkalsprobleem hier tans meer onder beheer as 30 jaar gelede, asook in sommige ander dele in die Suid-Vrystaat en Suid-Afrika. Die rede hiervoor word toegskryf aan ‘n beter begrip en beplanning van jagtogte. In die laat 1980’s was die gemiddelde skade per boer +/- 200 skaap per jaar. Die huidige verlies is ongeveer 40 skaap per jaar (gemiddeld per boer). Hierdie studie poog om die skade-veroorsakende probleem in die studie-area verder te verbeter deur akkurate voorspellings en beplannings te maak ten einde verliese te verminder. In die studie-area word piek verliese jaarliks aangeteken vanaf Augustus tot Oktober en Maart tot Mei. Die rooijakkals beweeg hoofsaaklik volgens bepaalde vaste patrone in die studie-area en broeipare reageer klaarblyklik op dieselfde stimuli van hul direkte omgewing. Dieselfde broeiplekke word herhaaldelik gebruik en daar is ‘n duidelike verwantskap tussen die ligging van die broeiplekke en menslike aktiwiteite. Wanneer ’n broeipaar verwyder word uit ’n gebied, neem dit nie baie lank voordat ’n nuwe broeipaar daar vestig nie. Die verwerking van historiese data het gelei tot voorspellings oor waar rooijakkalse gaan bly, waar gebroei gaan word en waar en wanneer hulle bes moontlik skade gaan aanrig. Dit voorspel ook waar hulle moontlik uitgevang kan word. Hierdie studie toon ‘n sterk verband tussen die fisiese aard van die omgewing en die rooijakkals aan.
Dissertation (M.Sc. (Geography))--University of the Free State, 2010
Keywords: Black-backed jackal -- Ecology -- South Africa -- Free State; Black-backed jackal -- Behavior -- South Africa -- Free State; Black-backed jackal -- Control -- South Africa -- Free State; Black-backed jackal -- Habitat -- South Africa -- Free State