| Summary: | Thesis (MScConsEcol)--University of Stellenbosch, 2011. === ENGLISH ABSTRACT: Anthropogenic habitat transformation and subsequent fragmentation of natural vegetation is
regarded as one of the largest threats to biodiversity in the world. The Cape Floristic Region
(CFR) in the Western Cape Province of South Africa is classified as a biodiversity hotspot due to
its high plant species diversity and endemism. Increasing growth in agricultural activities in this
region has contributed to fragmentation of pristine natural vegetation. A diverse assemblage of
small mammal species are found in this region, but very little is known with regard to their
ectoparasite diversity. More importantly, no information is available on the effect of
fragmentation on parasite burdens or species assemblages. The aims of the study were first to
record relative density, average body size and body condition of an endemic rodent, Rhabdomys
pumilio, trapped in two habitat types (pristine natural areas and remnant fragments). Secondly,
compare diversity and species composition of ectoparasite species on this rodent in the two
habitat types. In addition, body size measurements of the two most abundant flea species were
recorded and compared for the two habitat types. Lastly, temporal variation in mean abundance
of fleas, mites, ticks and the louse were recorded within a habitat fragment surrounded by
vineyards. Three hundred and ten individuals of the Four-striped mouse, R. pumilio, were
trapped and euthanized at 8 localities (4 remnant habitat fragments and 4 pristine natural areas)
in the CFR. All ectoparasites were removed and identified. A total of 8361 ectoparasites that
consisted of 6 flea, 1 louse, 8 mites and 11 tick species were recorded. Mites and fleas were
found to be more abundant on mice during cool wet months, whereas ticks and the louse were
more abundant during the hot dry months of the year. Rodent host body size was larger and they
were in better body condition in remnant fragments compared to pristine natural localities. A
positive body size relationship was found between the flea, Listropsylla agrippinae, and the host,
with larger fleas recorded on rodents that occur in fragments. Mean abundance and prevalence of
overall ectoparasites combined and separately for ticks, mites, louse and fleas were higher in
fragments compared to natural localities. The study shows that R. pumilio is host to a large
diversity of ectoparasite species in the CFR. Moreover, habitat fragments within agricultural
landscapes can facilitate higher parasite burdens and prevalence in rodent populations. This can
lead to an increase in disease risk given that several of the parasite species are important vectors
of pathogens that can cause disease in domestic, wild animals and humans. === AFRIKAANSE OPSOMMING: Menslike habitat transformasie en die daaropvolgende fragmentasie van natuurlike plantegroei
word beskou as een van die grootste bedreigings vir biodiversiteit in die wêreld. Die Kaap
Floristiese Streek (KFS) in die Wes-Kaap Provinsie van Suid-Afrika word geklassifiseer as 'n
biodiversiteit ‘hotspot’ as gevolg van sy hoë plant spesies diversiteit en endemisme. Toenemende
groei in landbou-aktiwiteite in hierdie streek het ook bygedra tot die fragmentasie van ongerepte
natuurlike plantegroei. 'n Diverse versameling van die klein soogdier spesies word in hierdie
streek aangetref, maar baie min is bekend met betrekking tot hul ektoparasiet diversiteit. Meer
belangrik, geen inligting is beskikbaar oor die effek van fragmentasie op parasietladings of
spesie samestelling nie. Die doel van die studie was eerstens om relatiewe digtheid, gemiddelde
liggaams grootte en kondisie van Rhabdomys pumilio aan te teken vir twee habitat tipes
(ongerepte natuurlike area en oorblyfsel fragment). Tweedens was die diversiteit en
spesiesamestelling van ektoparasiete op R. pumilio vergelyk vir die twee habitat tipes. Daarna
was die liggaams grootte metings van die twee mees volopste vlooi spesies aangeteken en
vergelyk vir die twee habitat tipes. Laastens was die seisonale variasie van die gemiddelde
hoeveelheid vlooie, myte, bosluise en die luis aangeteken binne 'n habitat fragment omring deur
wingerde. Drie honderd en tien individue van die vier-gestreepte muis, R. pumilio, was gevang
op 8 plekke (4 oorblyfsel habitat fragmente en 4 ongerepte natuurlike areas) in die KFS en
daarna was die diere uitgesit. Alle ektoparasiete was verwyder en geïdentifiseer. 'n Totaal van
8361 ektoparasiete wat bestaan het uit 6 vlooie, 1 luis, 8 myte en 11 bosluis spesies was
aangeteken. Myte en vlooie gevind was meer volop op muise tydens die koel nat maande, terwyl
bosluise en die luis meer volop was gedurende die warm droë maande van die jaar. Knaagdier
gasheer liggaam was groter en in 'n beter kondisie in die habitat fragmente in vergelyking met
ongerepte natuurlike areas. 'n Positiewe liggaam grootte verwantskap was tussen die vlooi,
Listropsylla agrippinae, en die gasheer gevind, met groter vlooie aangeteken op knaagdiere wat
voorkom in fragmente. Gemiddelde hoeveelheid en voorkoms van die totale ektoparasiete
gekombineer en afsonderlik vir bosluise, myte, die luis en vlooie was hoër in fragmente in
vergelyking met natuurlike areas. Die studie toon dat R. pumilio gasheer is vir 'n groot
verskeidenheid van ektoparasiet spesies in die KFS. Daarbenewens kan habitat fragmente binne
landbou landskappe hoër parasietladings en voorkoms in knaagdier bevolkings fasiliteer. Dit kan lei tot 'n toename in siekte risiko, gegee dat verskeie van die parasietspesies belangrike vektore is
van patogene wat siektes kan veroorsaak in huishoudelike, wilde diere en die mens.
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