Faecal analysis suggests generalist diets in three species of Western Cape cordylids

Climate has been proposed as an explanation for the present-day distribution of closely-related melanistic and non-melanistic cordylid species in the southwestern Cape of South Africa. However, diet may also contribute towards shaping geographic distributions. We present preliminary data on diet composition based on analyses of faecal pellets of Cordylus cordylus (non-melanistic), C. niger (melanistic) and C. oelofseni (melanistic). Coleoptera were the most common prey ingested both in summer and early spring for all species, followed by Hymenoptera for all species in summer. The overlap in other arthropod taxa ingested was low across species and seasons, suggesting an opportunistic component to their foraging behaviour.We distinguished plant matter in faecal samples of all species in all seasons, reflecting either voluntary or accidental ingestion. The results of this study suggest that the generalist diets of these cordylid species should not constrain their distributions despite the common preference for coleopterans.     

A model explaining patterns of geographic character variation in Cordyius cordylus (Reptilia; Cordylidae) in the south-western Cape,South Africa

A model is proposed for the evolution of three morphotypes of the girdled lizard Cordylus cordylus (Linnaeus) in the south-western Cape. The available data are interpreted as indicating that a vicariant splitting of a warm-adapted ancestral population during the last glacial period occurred. Differential evolution of the two daughter populations in response to different environmental pressures resulted. One of the daughter populations remaining in the coastal lowlands to the west of the Cape Fold Mountains, became cold-adapted, an event which was followed by a rapid range expansion. The other daughter population to the south and east of the Cape Fold Mountains apparently experienced less severe climatic conditions, maintained a larger population size, and for these reasons remained warm-adapted. During the subsequent warmer, interglacial period the now cold-adapted daughter population was again fragmented into two populations. Of these, one is presently found along the south-western coast and the other along the higher peaks of the western section of the Cape Fold Mountains. On the other hand the amelioration of the climate during the interglacial allowed the warm-adapted daughter population to the south and east to expand its range, eventually penetrating into the areas formerly occupied by the cold-adapted populations. Subsequently zones of secondary contact were established. In the area under discussion similar patterns of contraction and expansion can be observed in other closely related species. Our data support the turnover-pulse hypothesis of Vrba (1985)     

Cordylus Minor: A valid species of South african lizard (Reptilia: Cordylidae)

The taxonomic status of Cordylus cordylus minor FitzSimons 1943 is reconsidered. An analysis of variation in external morphological characters shows minor and cordylus to be two non-overlapping sets of organisms. A phylogenetic study shows the minor-cordylus set to be non-monophyletic, leaving no option than to consider minor a separate species.     

Are melanistic populations of the Karoo girdled lizard,Karusasaurus polyzonus,relics or ecotypes? A molecular investigation

It has been proposed that melanism in cordylids evolved in response to a single climatic event and that melanistic populations of Karusasaurus polyzonus are relictual. This study investigates the genetic relationships of melanistic and non-melanistic populations of K. polyzonus along the west coast of South Africa. Thirty-five specimens of K. polyzonus werecollected from three ‘melanistic’ and eight ‘non-melanistic’ sample localities. Partial sequence data were derived for two mitochondrial DNA loci (16S rRNA and nicotinamide adenine dinucleotide dehydrogenase component 2 (ND2)) and analysed using maximum parsimony, maximum likelihood and Bayesian inference. In addition, a haplotype network was constructed using TCS and an analysis of molecular variance (AMOVA) was conducted. The derived topologies were highly congruent and showed that melanistic and non-melanistic populations were interdigitated on all tree topologies and a number of haplotypes were shared between melanistic and non-melanistic specimens. These results suggest that melanistic populations of K. polyzonus are ecotypes, not relics.     

Sexual dimorphism in two girdled lizard species,Cordylus niger and Cordylus cordylus

The extent of sexual selection in two girdled lizard species was evaluated by measuring sexual dimorphism in those characters normally affected by sexual selection. Neither Cordylus niger, a cool-adapted species, nor C. cordylus, a warm-adapted species, displayed any notable sexual differences in asymptotic body sizes, but both species displayed slight dimorphism in head size measurements. The C. niger sample contained more large males than large females, which may be attributed to a lower growth rate in females. In the cool Saldanha area, females of both species lack generation glands. In the warmer Gansbaai area, these glands are present in females of C. cordylus, but in lower numbers than in males. Sex ratios favouring females, have been recorded for both species. The observed sexual dimorphism in the two species seems to be mainly the result of differential energy allocation by females, and not of sexual selection perse.     

Effect of temperature on growth,survival and reproduction of Bulinus nyassanus (Smith, 1877) (Mollusca: Gastropoda) from Lake Malawi

Bulinus nyassanus, endemic to Lake Malawi, is an intermediate host for Schistosoma haematobium and plays an important role in transmission of this parasite along some shorelines on the Nankumba Peninsula in the southern part of the lake. Density of B. nyassanus in shallow water is usually low from January to April and a major population increase takes place during May to August when water temperatures are relatively low (about 22°C) and supposedly suboptimal for B. nyassanus. This study was designed to compare performance (growth, reproduction, survival, and hatchability of egg-masses) of B. nyassanus at four constant temperatures (22, 25, 28 and 31°C). Survival and reproduction were optimal at 25°C while growth and egg development were faster at the higher temperatures. Findings are discussed in view of the population dynamics of B. nyassanus at Cape Maclear.     

Metabolic rate and body temperature of an African sunbird,Nectarinia Chalybea: daily rhythm and the effect of ambient temperature

The oxygen consumption (VO₂) of the lesser double-collared sunbird, Nectarinia chalybea. was measured at ambient temperatures (Ta) from 7 to 35°C. The diel variation in body temperature (Tb) and wet thermal conductance (C) was also determined. The sunbirds (mean mass 8,36 g ± S.E. 0.21 g) showed a pronounced diel cycle of VO₂, with a mean reduction of 50% at night. Basal metabolic rate was estimated to be 3.23 ml O₂/g.h, which is 88% of the predicted value for a passerine bird of this size. There was a mean reduction in Tb of 3.6°C at night. Both day and night values of Tb decreased with decreasing Ta, as did individual values of C. Winter breeding in the south-west Cape is energetically stressful for lesser double-collared sunbirds, but they have the physiological capacity to reduce their energy expenditure substantially at night.     

Digestion rates of prey eaten by intertidal sea anemones from the south-western Cape,South Africa

Digestion rates were determined for natural prey items offered to each of seven species of sea anemones found at Wooley’s Pool in False Bay and to the single species (Bunodactis reynaudi) recorded at Biouberg on the Atlantic coast of the south-western Cape, South Africa.This was done by examining prey items removed from the coelenterons at regular intervals after feeding and assessing their degree of digestion according to a predetermined scale. There was considerable variation in the gut retention times between different anemone species offered the same prey types, with Actinia equina consistently showing the shortest gut retention times (12 h for amphipods, 15 h for pelecypods and 23 h for isopods). Of the various prey categories tested, amphipods tended to be the most rapidly digested group, while molluscs and echinoderms usually remained in the coelenteron the longest. Mean gut retention times in B. reynaudi, the only species found both in False Bay (17°C) and on the cold west coast (12°C) were markedly longer (72 vs 60 h and 43 vs 30 h for pelecypods and gastropods respectively) at the lower temperature.     

Comparative behaviour and ecology of two sympatric mongoose species (Cynictis penicillata and Galerella pulverulenta)

The activity, movements, home range size, habitat selection, social structure, density, pattern of faeces deposition, anti-predator behaviour, diet, and availability and distribution of the main food sources of two mongoose species [the yellow mongoose Cynictis penicillata and the Cape grey mongoose Gaierelia pulverulenta (= Herpestes pulverulentos) in a coastal area of South Africa are compared, Both species were diurnal. Galerella did not use dens, whereas Cynictis never rested outside a den. Total distance moved, home range size and density did not differ between the two species. Galerella frequented bush, whereas Cynictis frequented open fields. The yellow mongoose was more social than the grey mongoose, but the basic social structure was similar. Faeces of Cynictis were found in large clumps close to the dens, while those of Galerella were more scattered. This parallels the greater constancy of use of the sleeping sites by Cynictis. Rodents (> 90% of Cape grey mongoose diet) were much more abundant in the bush, while availability of insects (main food source for the yellow mongoose) was higher in the open fields. Habitat selection, Ihrough its effects on anti-predator and feeding strategies, might have been the leading factor in the evolution of sociality in herpestids.     

Comparison of Cape Town and Skirrow's <Emphasis Type="Italic">Campylobacter</Emphasis> isolation protocols in humans and broilers in Morogoro,Tanzania

Comparison of Cape Town and Skirrow's protocols used in isolation of Campylobacter in humans and broilers was carried out in a cross-sectional study in Morogoro, Tanzania. A total of 176 and 158 human stool and broiler intestinal samples were collected, respectively. While human stool samples were collected from selected health centers, broiler intestinal samples were obtained from selected farms and chicken markets. Samples were inoculated and cultured in duplicate using two protocols and prevalence of Campylobacter were established. In humans, the prevalence of Campylobacter isolates was significantly higher (P < 0.001) (21.6%) with Cape Town protocol than Skirrow's method (9.1%). Similarly, a higher prevalence (P < 0.05) in broilers was recorded in Cape Town protocol (77.8%) than Skirrow's method (66.5%). There was a moderate (0.53) Kappa test of agreement between Skirrow's and Cape Town protocols for human samples and substantial agreement (0.72) for broiler samples. This demonstrates that Cape Town protocol is superior over the Skirrow's protocol in Campylobacter isolation. Campylobacter jejuni, Campylobacter coli and Campylobacter lari were the Campylobacter spp. isolated. In humans, C. jejuni accounted for 92.1% and 87.5% of all positive samples with Cape Town and Skirrow's protocols, respectively. In broilers, C. jejuni was isolated at 91.1% and 92.5% of all species obtained with Cape Town and Skirrow's protocols, respectively. This shows that C. jejuni is the common species that may be circulating from either broilers to humans or other animals and vice versa. The present study has introduced Cape Town protocol in Tanzania for Campylobacter isolation from human and animal samples, which is expected to improve the isolation of Campylobacter species. Cape Town protocol may also be a good alternative for use in routine isolation of Campylobacter.     

Temperature and mass scaling affect cutaneous and pulmonary respiratory performance in a diving frog

Global climate change is altering patterns of temperature variation, with unpredictable consequences for species and ecosystems. The Metabolic Theory of Ecology (MTE) provides a powerful framework for predicting climate change impacts on ectotherm metabolic performance. MTE postulates that physiological and ecological processes are limited by organism metabolic rates, which scale predictably with body mass and temperature. The purpose of this study was to determine if different metabolic proxies generate different empirical estimates of key MTE model parameters for the aquatic frog Xenopus laevis when allowed to exhibit normal diving behavior. We used a novel methodological approach in combining a flow-through respirometry setup with the open-source Arduino platform to measure mass and temperature effects on 4 different proxies for whole-body metabolism (total O₂ consumption, cutaneous O₂ consumption, pulmonary O₂ consumption, and ventilation frequency), following thermal acclimation to one of 3 temperatures (8°C, 17°C, or 26°C). Different metabolic proxies generated different mass-scaling exponents (b) and activation energy (E_A) estimates, highlighting the importance of metabolic proxy selection when parameterizing MTE-derived models. Animals acclimated to 17°C had higher O₂ consumption across all temperatures, but thermal acclimation did not influence estimates of key MTE parameters E_A and b. Cutaneous respiration generated lower MTE parameters than pulmonary respiration, consistent with temperature and mass constraints on dissolved oxygen availability, SA:V ratios, and diffusion distances across skin. Our results show that the choice of metabolic proxy can have a big impact on empirical estimates for key MTE model parameters.     

Soil carbon dioxide effluxes from different vegetation environments in semi-arid Eastern Cape,South Africa

Though important, CO₂ effluxes from non-agricultural ecosystems are poorly characterised. Given that thicket vegetation is prevalent in Eastern Cape, South Africa, we monitored soil CO₂ effluxes from an intact thicket, degraded thicket (DT) and grassland (G) over 10 months, as affected by temperature, moisture and penetration resistance (PR). High soil moisture (16%) reduced PR (4?kg cm^?2), which raised winter effluxes (1.2 µmol m^?2 s^?1), while low moisture (2%) resulted in hard dry soil (14?kg cm^?2) that suppressed spring effluxes (0.2 µmol m^?2 s^?1). There was good interaction between PR and moisture (r = ?0.53), with seasonal effluxes increasing with increasing moisture (r = 0.9, p = 0.0001) and decreasing PR (r = ?0.66, p = 0.02). Temperature effects were significant under unlimited moisture supply. Thus high summer temperature (40 °C) gave lower effluxes in DT and G (<1 µmol m^?2 s^?1) due to limited moisture (<10%), whereas high autumn temperature (48 °C) and good moisture (16%) accelerated CO₂ emissions (averaging 2 µmol m^?2 s^?1) from all covers. Although semi-arid ecosystems are limited by low moisture and sandy soils, they contribute to CO₂ emissions under high moisture and increasing temperature. Keywords: Eastern Cape, grassland, soil carbon dioxide effluxes, soil organic carbon, thicket     

Influences of fermentation and ripening temperatures on the enzymatic activity and physicochemical and sensory properties of salted egg white sufu

This study developed a novel form of sufu. Salted egg white sufu (SEWS) was produced by fermenting steamed salted egg white with douchi koji and ripening at 25°C, 35°C, or 45°C for 19 days. The results show that the protease activity of the koji reduced pronouncedly during fermentation, whereas the one in the SEWS initially increased but subsequently decreased. The total nitrogen and amino nitrogen contents and degree of protein hydrolysis increased during fermentation and decreased during preripening. SEWS, particularly processed at 35°C, contained more free amino acids, notably glutamic acid and leucine, than steamed salted egg white did. After processing, SEWS had darker colors, particularly when manufactured at higher temperatures, and hardness and springiness decreased. The 35°C and 45°C SEWS had higher sensory acceptability. In conclusion, ripening at 35°C for 19 days is recommended for producing this novel animal protein‐based sufu.     

Distribution of Neoehrlichia mikurensis in Ixodes ricinus ticks along the coast of Norway: The western seaboard is a low‐prevalence region

Neoehrlichia mikurensis is a tick‐borne pathogen widespread among ticks and rodents in Europe and Asia. A previous study on Ixodes ricinus ticks in Norway suggested that N. mikurensis was scarce or absent on the south‐west coast of Norway, but abundant elsewhere. The aim of this study was to further investigate the prevalence and distribution of N. mikurensis along the western seaboard of Norway in comparison with more eastern and northern areas. The second aim of the study was to examine seasonal variation of the bacterium in one specific location in the south‐eastern part of Norway. Questing I. ricinus were collected from 13 locations along the coast of Norway, from Brønnøysund in Nordland County to Spjærøy in Østfold County. In total, 11,113 nymphs in 1,113 pools and 718 individual adult ticks were analysed for N. mikurensis by real‐time PCR. The mean prevalence of N. mikurensis in adult ticks was 7.9% while the estimated pooled prevalence in nymphs was 3.5%. The prevalence ranged from 0% to 25.5%, with the highest prevalence in the southernmost and the northernmost locations. The pathogen was absent, or present only at low prevalence (<5%), at eight locations, all located in the west, from 58.9°N to 64.9°N. The prevalence of N. mikurensis was significantly different between counties (p < .0001). No significant seasonal variation of N. mikurensis prevalence was observed in the period May to October 2015. Our results confirm earlier findings of a low prevalence of N. mikurensis in the western seaboard of Norway.     

Aspects of the ecology of feral cats on Dassen Island,South Africa

Numbers of feral cats on Dassen Island (33°25'S/18°06'E) increased from 20–25 in May 1979 to 37–50 in June 1980. Kittens were born in eight months of the year with birth peaks in October-November and in January. Mean litter size was 2,7 and 80% of kittens born between August 1979 and January 1980 survived until June 1980. Kittens died from starvation and disease. In June 1980 51–56% of the cats were <1 year old. The number of cats is recovering rapidly from heavy culling. Depredation by cats is a potential threat to sea-bird colonies. The diet and feeding behaviour of the cats were studied in order to assess the importance of this threat. An ‘average’ cat's annual diet, assessed from scats, included: 134 European rabbits (Oryctolagus cuniculus), 37 jackass penguins (Spheniscus demersus), 25 Cape cormorants \Phalacrocorax capensis), 31 other birds and 24 house mice (Mus musculus). Each cat killed 105 rabbits and 13 birds each year, the balance of its diet being made up by carrion. Adverse effects of the presence of cats, compared to other factors, were not yet so serious as to necessitate artificial control of cat numbers.     

Zur Problematik der Klimaempfindlichkeit bei Haustieren*

In a group of 6 young German Black and White bulls it was investigated whether the jollowing criteria of the ejaculate volume density total number of sperms per trial day mass motion (total) forward motion local motion proportion of morphologically alterated sperms pH value pH alteration in 5 hours can be influenced individually by thermal loading. The loadings were performed in a climatic stall over 9 days at + 30’C during daytime and + 25° C at night, and at + 35°C and + 30° C respectively. Before and after the loading periods there were normal control periods at+15°C during daytime and+12°C at night. An analysis of variance was done regarding the stress periods, the individual animals and the interactions animals to periods. Regarding the alterations by the thermal loading periods the first (weaker) one at + 30°/+ 25°C hardly proved any effect on the variables mentioned. But the second (stronger) period at + 35°/+ 30° C alterated nearly all the variables at a high degree and partially in such a manner that the starting values of the control period could not in all cases be normalized again up to 10 weaks after the loading period. Considering the intensity and duration of the reactions of the individuals there were distinct differences. Especially 2 animals in the test population were reacting outstandingly, one in a positive manner, the other particularly negatively. 12¹/₂ weeks after the loading periods, at the end of the observations the latter was still unable to regain normal values. The question whether this was a permanent defect unfortunately could not be pursued. The reaction of the other 4 animals was intermediary to the two extremes. On the basis of these and previous results it is supposed that there is a variation in the thermosensibility also within the German Black and White cattle, a factor which might be accessible as a criterion of selection.     

Movement behaviour of largemouth bass Micropterus salmoides in a South African impoundment

The objectives of this study were to describe movements and area use patterns of largemouth bass Micropterus salmoides in relation to abiotic factors (water temperature, river inflow and water level). The study was conducted in the Kubusi arm of Wriggleswade Dam, Eastern Cape, South Africa where nine largemouth bass (310–385?mm FL) were surgically implanted with individually coded acoustic transmitters and monitored for nine months (May 2010 to January 2011) using an array of five moored acoustic data-logging receivers. The daily position occupied by largemouth bass was significantly affected by water temperature (P<0.001) and river inflow (P<0.001), whereas water level had no effect. Largemouth bass spent little or no time in the shallow river inlet areas when water temperature was <12.5 °C, but as water temperature increased, their utilisation of shallow areas increased significantly. The results from this study demonstrate the importance of environmental factors, particularly water temperature, on the movement of largemouth bass.     

A review of the Namaqua gecko,Pachydactylus namaquensis (Reptilia: Gekkonidae) from southern Africa,with the description of two new species

An analysis of morphological and allozyme variation in the Namaqua gecko, Pachydactylus namaquensis from southern Africa is presented. Three separately evolving lineages, well defined by morphology and allozyme variation, are identified. The isolated southern population, occurring on the southern escarpment and Cape Fold Mountains surrounding the western Little Karoo, is named P. kladamderma sp. nov., and is characterized by a slit-like ear opening, low number of granules bordering the mental (3-6) and mental and adjacent infralabials (513), the frequent (79%) occurence of the supralabial entering the nostril, and its drab brown base colouration. A northern population, occurring in southern Namibia and the Richtersveld is named P. haackei sp. nov., and is characterized by its more rounded or squared ear opening; high number of granules bordering the mental and adjacent infralabials (11-19), the general exclusion of the supralabial from the nostril (only 3.7% entry), and brighter, lighter colouration. It is further differentiated from P. kladaroderma on the basis of fixed differences at 11 allozyme loci. Both new species differ from P. namaquensis, which is mainly restricted to Little Namaqua- land, but is sympatric with P. haackei in the Lower Orange River region, by their more heterogenous dorsal scalation, smaller cloacal spurs, lack of spine-like tubercles on the lateral surfaces of the tail, and more fragile skin. The type locality of P. namaquensis is restricted to ‘the vicinity of Springbok, Little Namaqualand, Northern Cape Province, South Africa’.     

Movement patterns of Lichia amia (Teleostei: Carangidae): results from a long-term cooperative tagging project in South Africa

Understanding fish movement patterns and migrations is important for fisheries management as well as the identification and conservation of critical habitats. Data collected by the Oceanographic Research Institute's Cooperative Fish Tagging Project (ORI-CFTP) were used to describe the large-scale movement patterns of Lichia amia along the South African coastline. A total of 10 762 L. amia were tagged between 1984 and 2012, of which 744 (7%) were recaptured. Most tagging effort, mainly on juvenile and subadult individuals, took place along the south-eastern (i.e. Eastern Cape) and south-western (i.e. Western Cape) regions of the country during summer. Conversely, more L. amia were tagged and recaptured (mostly adults) during winter and spring (July to November) along the north-east coast (i.e. KwaZulu-Natal). Movements (dispersal distance in kilometres) by juveniles were restricted and largely confined to estuaries within the south-eastern and south-western regions of the country. There was a significant effect of fish size on distance moved (ANOVA: p<0.001), with evidence of a distinct seasonal (winter) longshore migration by adults to KwaZulu-Natal. The consequences of juvenile residency in estuarine habitats and high recapture rate of adults during a directed, seasonal spawning migration are discussed in light of improving current fisheries management.     

Climatic and edaphic conditions at eragrostis lehmanniana nees sites in Arizona,USA and the cape province,RSA and potential seeding sites in Southern Africa

Climatic and edaphic conditions at Eragrostis lehmanniana Nees sites in southeastern Arizona, USA were compared with those in the Cape Province, RSA to determine a range of conditions under which the species might be expected to establish and persist in southern Africa. Mean annual precipitation amounts and temperature extremes were highly variable where Lehmann lovegrass predominates, but in most summers precipitation accumulations ranged from 150–220 mm and temperature extremes ranged from 20–35°C in 30–40 days. Soils at Lehmann lovegrass sites in the Cape Province were more coarse textured and nutrient concentrations were usually less than at sites in southeastern Arizona; but trends in particle‐size distributions and measured chemical concentrations were generally equivalent. Climatic and edaphic conditions in central Botswana and northeastern Namibia generally range between those in southeastern Arizona and the Cape Province, RSA and we expect that seeded Lehmann lovegrass stands in these areas would enhance semi‐desert grassland productivity.