Zoology

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The herpetology of south-east Africa.
(1966) Broadley, Donald George.; Poynton, John Charles.
No abstract available.
Intersex in four South African racial groups in Durban.
(1970) Grace, Hatherley James.; Bain, Peter G.
Chapter I The ontogeny of sex development is introduced and a definition of the intersexual state is given. A resume of intersexes recorded in South Africa is presented together with figures showing the increased demand for cytogenetic services in the country. The motivation for this study is discussed. Chapter II The biological concept of sex is outlined together with notes on the evolution of the dioecious state in animals. Thereafter a brief account of the normal and abnormal intersex states in invertebrates and vertebrates is given. Chapter III Examples of some of the abundant references to ambisexual individuals found in the classical literature, history and mythology are listed and the status of intersexes in modern society is discussed: it does not vary much from the times of ancient Greece and Rome. Chapter IV A summary of the events which led to the establishment of cytogenetics as an independent discipline is given. The discovery of nuclear sex dimorphism is noted and methods of investigation of intersexual patients are described. A detailed description is given of cytogenetic technical. "methods, ; and leads to a diagrammatic explanation of the differential diagnosis of intersexes. This is used as a basis for the classification and accordingly a simplified, unambiguous system is proposed and defended. The sources and numbers of pat~ ients recorded in this thesis are explained. Chapter V The sex chromatin is described in detail? with a description of the methods used for its demonstration and evaluation. A pilot study of normal women of the four races established that there is no inter-racial variation in chromatin frequency. Reasons are given for disregarding nuclear appendages as an accurate indication of 'sex '. Chapter VI Embryological stage s i n the development of the human urogenital tracts are recounted after considering the mechanisms of sex determination. Pathogenesis of intersexuality is considered briefly. Chapter VII Gonadal dysgenesis of the female, including Turner's syndrome and phenotypes of both male and female are presented. The classification, pathology, aetiological and cytogenetic factors are described. Illustrative case reports and extensive discussion of the syndrome are presented. Chapter VIII The Klinefelter syndrome occurs in males with supernumerary X chromosomes; a number of chromatin negative, hypogonadal conditions mimic the syndrome: they are described, with notes on the classification, pathology, aetiology and the cytogenetic features. A series of case reports demonstrate both chromatin positive and negative types. Special reference is made to the dermatoglyphic profiles which were discovered to differentiate the XY males into two groups. Chapter IX Three syndromes, the XXX, XYY and agonadism, were not encountered in this study and are consequently not discussed. Chapter X The adrenogenital syndrome has several distinctive signs which are mimicked by induced virilization; these are described and a number of case reports are presented to illustrate the syndromes. Chapter XI Male intersexes occur in several different forms: the classification of the group is explained and a distinction is made between intersexes and those with simple, or 'pseudo-intersexual', defects. The signs of the different syndromes are detailed, together with data concerning the aetiology and cytogenetics. A series of patients' case histories is used to illustrate the various syndromes. Chapter XII Idiopathic female intersexuality is defined and a short explanation of the classification is given. The signs found in this syndrome are detailed and a single case report, which is of exceptional interest because of severe masculinization and the formation of a phallic urethra, is presented. Chapter XIII Hermaphroditism is defined and the subgroups are explained. The variability of signs is discussed and details of anatomy and histology of the genital tract are given . A single hermaphrodite was encountered during the survey and the case is described. Three other patients, all infants, were suspected of being hermaphroditic but because gonadal biopsy was not undertaken they were discharged from hospital without a diagnosis having been made. Discussion of the aetiological mechanisms is presented and the need for early diagnosis and treatment is emphasized. Chapter XIV Some of the simple genital anomalies and somatic defects which resemble intersex are mentioned and are illustrated by attenuated case reports. Chapter XV The incidence of those intersexual conditions recognizable at birth by anatomical deformity is calculated from a total population of 21,000 live births recorded during the calendar year, 1969. The incidence was very low (1:7000) and does not permit analysis of inter-racial distribution. Prevalence is calculated from the number of new patients seen by the author during 1969 in Durban. Some interesting observations were made but the primary objective, to determine whether or not intersexuality is more prevalent in the Bantu than any other race, could not be answered with certainty because of the small number of patients. Hermaphroditism was shown not to be the most common type of intersex syndrome in the Bantu. Chapter XVI An outline is given of the normal dermatoglyphic features of the finger prints and palms. Some references of the patterns in Turner's and Klinefelter's syndromes are available from the literature and are compared with the profiles of patients from this series. A distinct dimorphism was found in chromatin negative hypogonadal males and was thought to distinguish between those with congenital or acquired pathology. Normal values for South Africans have not been established satisfactorily and the urgent need for this information is stressed. Chapter XVII A general discussion of the highlights of this study of the epidemiology, clinical presentation and cytogenetics of intersexuality is given and a number of conclusions are drawn .
The rock lobsters (Palinuridae) of South-East Africa, with particular reference to the life histories of Panulirus Homarus and Palinurus Delagdae.
(1970) Berry, Patrick Fleetwood.; Heydorn, A. E. F.
Abstract available in PDF file.
A review of the old world genera of Lauxaniidae (Diptera)
(1971) Stuckenberg, Brian Roy.; Bush, S. F.; Heeg, Jan.
This paper presents in key form a review of the Old World genera of Lauxaniidae. Thirteen new genera are erected, three genera are placed in synonymy, four subgenera are given generic status, and one genus is transferred from the Heleomyzidae. The development of lauxaniid generic classification is reviewed and a total of 126 recognised genera is obtained. An account is given of the regional distribution of Lauxaniidae; three main faunal aggregates are distinguished, namely the Neotropical, Holarctic and Old World tropical. The validity of certain characters for generic classification is discussed, and the suggestion is made that trigonometopine forms have evolved polyphyletically as adaptations for life in grass and comparable vegetation types. A division of the family into major groups of genera is considered, and a subfamily Homoneurinae is established. The validity of characters used to distinguish Cestrotus and Turriger is examined; a failure to find reliable characters results in the synonymy of the latter genus. Illustrated descriptions are given of the type-species of new genera.
The sea turtles of South East Africa.
(1973) Hughes, George R.; Heydorn, A. E. F.
Abstract available in PDF file.
Aspects of the biology and ecology of the estuarine fishes of the east coast of South Africa.
(1974) Wallace, John Henry.; Heydorn, A. E. F.
No abstract available.
Reproduction and population ecology of the blue wildebeest Connochaetes taurinus taurinus in Zululand.
(1977) Attwell, Charles Anthony Mallory.; Meester, Jurgens Anthonie Jansen.; Hanks, John.
A two-year study was made of the blue wildebeest Connochaetes taurinus taurinus in Zululand, Natal. Aspects investigated included age determination methods, growth and condition, reproductive physiology, habitat interactions, and population dynamics. Findings were related to suggested management of the species.
Ecological and systematic relationships in Natal ranids (Rana Linn. sensu stricto and sensu Strongylopus Tschudi) with notes on a possible competitor, the leptodactylid Heleophryne natalensis Hewitt.
(1977) Channing, Alan Eric.; Van Dijk, D. E.
No abstract available.
Comparative studies on related free-living and pathogenic limax amoebae with particular reference to Naegleria.
(1977) Lastovica, Albert Joseph.; Meester, Jurgens Anthonie Jansen.
Over two hundred and forty strains of limax amoeba including eight potentially pathogenic strains of Naegleria and Acanthamoeba were isolated from a variety of habitats in South Africa. The amoeboid and flagellate stages of all Naegleria strains examined by light microscopy were found to be similar in morphology. Differences were noted in the excystment of Naegleria fowleri, Naegleria gruberi and other limax amoebae. Time-lapse microcinematography has been utilised to study cytokinesis and motility in the amoeboid and flagellate stages of Naegleria fowleri and Naegleria gruberi. A new phenomenon was observed in Naegleria where amoebae attempted cytokinesis after brief exposure to a temperature of 9°C. The amoeboid and flagellate stages of virulent and avirulent Naegleria were found to be similar in surface topology when examined under the scanning electron microscope. Differences were noted in the excystment patterns of various limax amoebae. No structure suggestive of a surface active lysosome was found in any of the cells examined. A comparative transmission electron microscope study of virulent and avirulent Naegleria and other limax amoebae has revealed striking similarities as well as sharply defined ultrastructural differences. Partioles suggestive of a virus were detected in several of the pathogenic Naegleria. Surface-active lysosomes were not found in any of the amoebae examined. Distinct feeding preferences were evident in Naegleria fowleri and Naegleria gruberi when they were tested on a variety of gram-negative and gram-positive bacteria. Differences were noted on the growth of these amoebae at various temperatures. Cell fractions of Pseudomonas aeruginosa affected excystment, encystment, cell division and the amoeba-to-flagellate transformation in Naegleria. Differences were observed in the transformation kinetics of Naegleria fowleri and Naegleria gruberi at 25ºC and 43º C. A variety of inhibitors affected motility and transformation in Naegleria. For the first time, La[3+]ion, a competitive inhibitor of Ca[2+]ion, was shown to inhibit amoeboid motion, transformation and flagellar beating in Naegleria. Electron microscope observation suggested that La[3+]ion acts on the plasmalemma. Material from two suspected cases of primary amoebic meningoencephalitis was examined and cultured but no limax amoebae were isolated. New criteria for the classification of virulent and avirulent Naeglerid. have been advanced.
The Squamata (Reptilia) of the Orange Free State, South Africa.
(1977) De Waal, Schalk Willem Petrus.; Meester, Jurgens Anthonie Jansen.
This study deals with the three orders of Squamata (Sauria, Amphisbaenia, Serpentes) of the Orange Free State, South Africa. Following an intensive systematic survey 4 492 specimens have been examined comprising 77 different species and subspecies of which 25% represent new records for the study area. Variation in taxonomically important characters as well as informa- tion on colour, size, habitat, breeding, predators and diet are discussed. Certain taxonomic changes have been made. Distribution maps have been compiled on the basis of eighth-degree-units. Distributional patterns have been analyzed to establish areas of relative homogeneity separated by transitional zones. A causal analysis of the main distribution patterns of the O.F.S. Squamata indicated that rainfall is the major environmental factor influencing distribution. A comparative analysis of the squamate areas has been done with regard to various biogeographic phenomena.
Aspects of the biology of the red bishop Euplectes orix and other Euplectes species.
(1977) Craig, Adrian John Fergus Knott.; Maclean, Gordon Lindsay.
The breeding biology and the annual cycle of the Red Bishop Euplectes orix was studied over a two year period in Natal. Some comparative data were also gathered for the related species the Red-shouldered Widow E. axillaris and the Red-collared Widow E. ardens, and additional data from a ringer in Rhodesia have been analysed. The breeding season of these polygynous ploceids coincides with the summer rainy season, and the amount of breeding activity in the Red Bishop appeared to be correlated with the amount of rain during the previous year. Breeding success at the colony studied was low; predation was the major cause of nest failure. In all three species the entire population, including the juveniles, undergoes a complete moult at the end of the breeding season. There is some evidence that the birds may make local movements during the winter dry season. These species are sexually dimorphic, the males being larger than the females. The population sex ratio was Significantly biased in favour of males in the Red Bishop and the Red-shouldered Widow but not in the Red-collared Widow. However, about half the male birds are subadults which do not breed, so that there is an excess of females in the breeding population. Adult males undergo a partial moult at the start of the breeding season and acquire a distinctive nuptial plumage. This is shed again at the post-nuptial moult, and in eclipse plumage they resemble the females. There is a similar pattern of weight change in all three species, with peaks early in the breeding season and again during the moult. The lowest annual weights are recorded during the dry season. The mortality rate of the Red Bishop is not high for a small passerine. The findings of this study are compared with the available information on other members of the genus, and discussed in relation to the evolution of polygyny in the Euplectes species.
The mammals of the Transvaal.
(1978) Rautenbach, Ignatius Lourens.; Meester, Jurgens Anthonie Jansen.
The primary object of this study is to provide a checklist of the mammals occurring within the Transvaal. A general biological account of each species forms the bulk of this treatise, - discussing, in order of sequence, firstly the taxonomic status of each species as based on a study of available museum specimens. Thereafter the distribution of each species is discussed, and illustrated with a map of known distribution. Remarks are presented on the various environmental factors that may influence individual species ranges. Habitat preferences, habits, and food preferences are then discussed. Available data on breeding seasonality, as based on the monthly ratio of reproductively active and inactive females, are given. External measurements and masses of males and females are tabulated. Records of occurrence based on the number of museum specimens from each locality, and the institution where these specimens are housed, are finally listed for each species. The text is supplemented by a gazetteer, giving the latitudinal and longitudinal coordinates of all the collecting localities. This study is based on some 12 000 museum specimens, the greatest majority housed in the Transvaal Museum collections. During the field work phase of this project, 57 localities were sampled. This yielded the majority of the specimens and the greater part of the data on which this book is based. Information gained from a study of earlier collected material supplements these data files. Additional information such as sight records, field observations, and the published accounts of other scientists, have also been incorporated into the central data files and have been discussed in relation to my own findings. The results of selected studies comprise the discussion. The basic behavioural trends and mean mass of all the carnivore species of the Transvaal are employed to speculate on how interspecific competition is avoided. The distribution of all southern African mammals is employed to statistically evaluate the validity of the biotic zones previously empirically recognized for this subcontinent. The distribution patterns of Transvaal mammals are statistically analysed to subdivide the biotic zones overlying the Transvaal into community types of zoogeographical significance. Other zoogeographical phenomena are discussed in relation to regional species diversity. Reprints of papers arising from this study, and particularly the discussion, are bound in as appendices to this report.
Systematics and bionomics of the scorpions of South West Africa (Arachnida, Scorpionida)
(1978) Lamoral, Bruno H.; Heeg, Jan.; Meester, Jurgens Anthonie Jansen.
All the taxa of scorpions previously described from South West Africa are revised and a monographic account presented with phylogenetic and biogeographic discussions and conclusions derived in terms of current concepts in systematic zoology which include cladistics and historical biogeography. South West Africa is treated as a subregion of the Afrotropical region and the limits of this subregion coincide broadly with the political borders. All the characters used are defined and illustrated. Many characters previously unstudied for the fauna are investigated. These include comparative studies of trichobothria distributions and detailed structures of the hemispermatophore. Disc electrophoresis of the haemolymph of a few species was carried out and the results discussed. Ecological factors are extensively described and discussed. The nature of the substratum, taken in its broadest possible definition, was found to be the most important single factor determining species distribution. 70 subgeneric taxa were revised, 45 of which are retained as valid, while 11 new species are described bringing the number of known species to 56. These are distributed among seven genera as follows: Buthotus, two species; Karasbergia, one species; Parabuthus, 14 species; Urop1ectes, 10 species; Hadogenes, three species; Lisposoma, two species; Opisthophthalmus, 24 species. Determination keys are provided for all levels of taxa occurring in South West Africa.
An outline of the ecology and behaviour of the red lechwe (Kobus leche leche Gray, 1850)
(1979) Williamson, Douglas Templin.; Meester, Jurgens Anthonie Jansen.
In a number of publications serious concern has been expressed about 'the status of lechwe in the Kwando/Linyanti/Chobe system. Concern has also been expressed about the effects of possible water extraction from the Okavango Delta on the habitat of lechwe in the delta. This study was motivated by this concern and was undertaken to provide information that would facilitate the conservation and management of lechwe in Botswana. Continuous field work on the western edge of the Linyanti Swamp began in January 1975 and ended in May 1977. Follow-up visits were made in February/March and September/October 1979. Data were collected on the following: variation in water l6vels, physiognomic and floristic characteristics of lechwe habitat, age determination, food habits, habitat use, distribution,condition growth, reproduction, non-social behaviour, social behaviour and organjsation and population status. From data collected it was concluded that, although there was no indication of a drastic population decline, the prevailing high water levels in the system were causing a downward trend in the population by pushing the animals into poorer quality habitat. The decline in the quality of the habitat available to the population was reflected by high juvenile mortality and reduced fecundity of young females. On the basis of the findings of this study a strategy for the conservation and management of lechwe in the Linyanti Swamp is proposed.
The population dynamics of impala (Aepyceros melampus Lichtenstein) in Mkuzi Game Reserve.
(1979) Vincent, John.; Meester, Jurgens Anthonie Jansen.; Jarman, Peter.
The need to understand the dynamics of the impala population in Mkuzi Game Reserve arose during the early 1960's when it became clear that various factors were contributing to an overpopulation of the species in the reserve. Population management was recognized as being necessary and was carried out, but it was based on inadequate information. This study set out to establish a rational basis for future management. The social organization and behaviour of impala in Mkuzi were analysed and placed in perspective relative to the population dynamics. Two methods of counting the animals were used and a relationship obtained between the respective results. The distribution of impala within the reserve, both on a gross population basis and with respect to the various sex and age categories, was determined from sampling. In order to establish the age structure of the population, samples obtained from the control programme were used, and these were aged on the basis of molar wear. At the same time the proportions of young animals and the population sex ratios were obtained by field sampling. Using these data, life tables were constructed, from . which it was possible to interpret the behaviour of the population at the time of the study. However, caution should be exercised in extrapolating these results literally to the same population under different conditions. The study only provides guidelines for regular monitoring to be carried out. At the same time a more detailed study of the vegetation dynamics of Mkuzi Game Reserve is a priority so that the relationship between the animal and plant elements of the reserve can be properly analysed.
The incidence of helminths in pigs, sheep, cattle, impala and blesbok in the Transvaal.
(1980) Horak, Ivan Gerard.
The seasonal fluctuations in the worm burdens of pigs, sheep, cattle, impala and blesbok exposed to infestation on improved or natural pastures in the Transvaal were determined. The prevalence of infestation in pigs slaughtered at the Pretoria Municipal Abattoir and in impala near Pafuri and blesbok at Badplaas was also established. Sheep, goats and cattle were successfully artificially infested with a number of nematodes of impala origin and sheep with those of blesbok origin. The various methods used to determine the seasonal incidence of helminth parasites are discussed and the wastage of valuable material criticised when complete recoveries of both internal and external parasites are not attempted at each necropsy. Host specificity and the distribution of parasites according to climate and the zoogeographical distribution of their hosts are discussed and the epizootiology of the major nematode genera parasitizing sheep, cattle, impala and blesbok in the Transvaal is determined. The phenomenon of arrested development in nematodes is compared with that of diapause in insects and measures to control helminth parasites 1n domestic stock and antelope in the Transvaal are suggested.
Aspects of the biology and population dynamics of freshwater mussels in Lake Kariba and Lake McIlwaine.
(1980) Kenmuir, Dale Harold Stafford.; Heeg, Jan.
Following preliminary observations in 1975 the Lake Kariba Fisheries Research Institute implemented a research program in March 1976 to investigate various aspects of the biology and population dynamics of the mussel crop of Lake Kariba, with a view to greater understanding of their status in the lake, and establishing a basis for management, if required. Aspects investigated were densities, distribution, species composition, predation by fish, reproduction, age and growth, gross biochemical composition and crude production rates. The mussel community comprised four species, a small pill clam, Corbicula africana, and three mussels, Caelatura mossarnbicensis, Aspatharia wahlbergi and Mutela dubia. Only the latter three were studied. Mussel beds occupied all the gently shelving cleared and uncleared areas, and the bulk of the populations occurred from 3 m - 9 m depth, but extending to 11 m. Predation by fish was found to be extremely low. The reproduction study showed two species bred all year C. mossambicensis and M. dubia, whereas A. wahlbergi bred seasonally during the rainy season. The two year-round breeders were repetitive spawners, capable of breeding several times a year. Indications are that A. wahlbergi is essentially a fluviatile species, with a life cycle adapted to taking advantage of riverine conditions. Sex ratios in all three species were approximately 1 : 1 , with females predominating slightly. Fecundity in one species, C. mossambicensis, was investigated. The complete parasitic cycle of M. dubia was elucidated and found to be similar to that of M. bourguignati, as described by Fryer (1961). Host species were noted amongst the cichlid and mormyrid families, and the conclusion drawn that the species is not host specific. various aspects of the life-cycles of the other two species were noted, but complete life-cycles were not successfully elucidated. population composition according to age showed the most common species, c. mossambicensis, to be comprised mainly of 2 - 5 year-old individuals, indicating a young and vigorous population. Juvenile pre-adult mussels were very scarce. In the population of A. wahlbergi, older mussels formed a greater proportion of the biomass than in the population of c. mossambicensis, and young were also scarce. M. dubia were not recorded in sufficiently large numbers to estimate age composition accurately. The production rate (whole wet mass) of the most common species, c. mossambicensis, was calculated to be 2,45 kg ha¯¹ day¯¹ in the sanyati East cleared area (30,5 km²), while the overall production rate of all three species was calculated to be 3,34 kg ha¯¹ day¯¹. Calorific values of all three species were obtained, while gross body composition in terms of water, fat, protein, ash and amino acid composition were determined. The ash component of A. wahlbergi was analysed. The Lake Kariba results were supplemented by a follow-up study of the composition of the mussel population of a eutrophic, highveld dam, Lake McIlwaine, in 1978/1979. This much smaller lake was populated by only two mussel species, M. dubia and C. mossambicensis, although A. wahlbergi and Unio caffer were recorded in the riverine upper reaches. Observations on seasonal breeding of the two lake species were made. A detailed study on the draw down zone of a gently shelving beach showed that at the time the extreme shallows had been dominated by C. mossambicensis, whereas from a depth of approximately 1,6 m M. dubia dominated very significantly. Fulling lake level was found to trigger off migratory responses, thus placing a proportion of individuals in deeper water and improving chances of survival. The mussel composition of Lake Kariba and Lake McIlwaine was considered in conjunction with preliminary observations of mussel distribution a nd composition in other water bodies, and some inferences drawn regarding the ecological factors which appear to influence the composition and diversity of the mussel fauna in rivers and lakes.
Social ecology of Otomys irroratus, Rhabdomys pumilio and Praomys natalensis.
(1982) Willan, Kenneth Brian Ronald.; Hickman, G.; Meester, Jurgens Anthonie Jansen.
This work sets out to describe the socio-ecological niches of otonya irroratus, Rhabdomys pumilio and Praomys natalensis in the Natal midlands. This objective necessitated a broad-based approach in which aspects of the ecological niches, and the social behaviour and social organization of the three species were investigated in field (habitat and trapping) and laboratory (experimental and observational) studies, during the period January 1976-May 1978. To test the assumption that the commonly sympatric O. irroratus, R. pumilio and P. natalensis are primarily adapted to habitats which differ mainly in respect of water availability, an attempt was made to define their positions on a mesic/xeric continuum. The results suggest that in terms of the parameters measured (responses to water and cover availability, and to food and water deprivation), O. irroratus is more nearly mesically adapted than is R. pumilio, with P. natalensis positioned between the two extremes. However, in the case of P. natalensis it is apparently of overriding importance that this species is adapted to disturbed habitats. The mesic habitats preferred by O. irroratus are often of limited size, but resource availability within these areas is apparently high and stable. Extensive areas of suitable habitat are available to R. pumilio, but availability of resources is seasonally variable. The disturbed habitats preferred by P. natalensis arise unpredictably in nature and, depending on the rate of ecological succession, may be short-lived; hence availability of resources to this species is highly unpredictable. Social behaviour was studied by means of dyadic encounters in the laboratory. Communication in O. irroratus, R. pumilio and P. natalensis appears to be dominated by auditory, visual and olfactory signals respectively, although O. irroratus also has well developed visual signals in its communicatory repertoire. These differences are explained mainly in terms of patterns of diel activity and habitat preferences: R. pumilio is adapted to bright light, and its visual signals are subtle; O. irroratus is adapted to dim light, and its visual signals involve gross changes in posture, while the use of loud, low frequency vocalizations would allow conspecifics to know their precise location in relation to one another in dense vegetation; P. natalensis is nocturnal, and hence appears to emphasize olfactory (and possibly ultrasonic) communication, which would permit transfer of information in the dark. O. irroratus is overtly highly aggressive, but agonism is ritualized; ritualization of aggression has probably evolved to allow high densities of this species to exploit limited areas of prime habitat. R. pumilio is less overtly aggressive than O. irroratus, but aggression tends to be unritualized; direct aggression probably acts as a spacing mechanism, and is possible in view of the large areas of habitat available to this species. Agonism is poorly developed and ritualized in P. natalensis, permitting high sociability and group formation in this species, and maximum exploitation of locally abundant resources. Social organization was studied in the field (trapping studies) and by means of dyadic encounters in the laboratory. The social system of O. irroratus appears to include temporal territoriality, which would permit animals to live in close spatial association (in small areas of habitat) while seldom actually meeting. Hierarchical ranking occurs in male O. irroratus and R. pumilio, with competition in both most likely being for mating opportunities. Breeding females of these two species are intrasexually territorial, in the case of Q. irroratus thereby providing dispersing young with adequate space for establishment of a home-range in prime habitat, and in R. pumilio protecting the young against conspecific female aggression until dispersal. R. pumilio tends to aggregate in mesic refuge habitats in winter, which apparently reflects the seasonality of resource availability to this species in drier environments. P. natalensis is colonial, an adaptation facilitating maximum exploitation of temporarily abundant resources in transitory disturbed habitats. In response to intense courtship by the male, female R. pumilio appear to undergo reflex ovulation; this strategy would maximize the chances of fertilization occurring during occasional meetings between males and females. Courtship intensity is low in P. natalensis, and presumably because the colonial social system of this species ensures frequent association between potential mates, females appear to ovulate spontaneously. Sexual activity was not observed in O. irroratus. The life-history tactics of the three species are such that o. irroratus and P. natalensis respectively appear to be K- and r-selected, with R. pumilio falling between these two extremes on an r-K continuum.
Aspects of the biology of the caracal (Felis caracal Schreber, 1776) in the Cape Province, South Africa.
(1982) Stuart, Christopher Trevor.; Hickman, G.
Felis caracal, despite heavy hunting pressure, is common and widespread throughout the Cape Province. Caracal are considered to be the principal wild predator of domestic livestock (goats and sheep) by most farmers and hunt clubs. Scat and stomach content analysis, as well as observations, indicate that F. caracal prey primarily on small to medium-sized mammals. The feeding habits of caracal-in different areas varied, according to abundance and occurrence of prey species. Captive animals required an average of 586g of meat each day. Killing techniques varied for different sized prey items. Physical and behavioural ontogeny are described for captive born animals. A technique for determining age of F. caracal was developed from study of known-age captive caracal. Examination of females killed in the wild, captive births, and births which were back-dated indicated that although young were born throughout the year, there was a definite birth peak between October and February with the lowest point being in May/June. Caracal were distinctly sexually dimorphic in size. Six F. caracal (four females and two males) were trapped, fitted with radio-transmitters, and released at the capture sites. Animals were cumulatively tracked for a total of 164 weeks. The mean range was 24,16km². A young adult male covered approximately 138km before settling in a 48km² area. Recommendations are presented for reducing losses of domestic stock by the caracal, based on the principal of removing the problem individual rather than blanket control.
A study of the blackshouldered kite Elanus caeruleus.
(1982) Mendelsohn, John Martin.; Maclean, Gordon Lindsay.
No abstract available.

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