Registered users receive a variety of benefits including the ability to customize email alerts, create favorite journals list, and save searches.
Please note that a BioOne web account does not automatically grant access to full-text content. An institutional or society member subscription is required to view non-Open Access content.
Contact helpdesk@bioone.org with any questions.
For over a decade, molecular short standardised DNA fragments, termed DNA barcodes, have been developed for species discrimination around the world. As of 2010, the vast majority of barcoding research was biased toward particular taxonomic groups and geographic regions largely because researchers in developed countries were the ones with the resources and capacity to carry out such work. To rectify this, the International Barcode of Life Project was launched with the intent to extend the geographic and taxonomic coverage of the barcode reference library. South Africa committed to this mission in an attempt to catalogue all of its known biodiversity and, possibly, help identify new species. To date, approximately 48 000 South African faunal barcodes are housed in the Barcode of Life Data System (BOLD), which represent only 2.3% of all known South African animal species. Although insects are the best represented in absolute terms, with over 37 000 samples recorded, they are still grossly lacking with just over 1% representation. Much like the global trend, there is a general taxonomic bias, with fish, birds and mammals showing the greatest representation. Moreover, geographic bias is also present, with the Free State province particularly under-represented on BOLD, likely owing to limited human capacity. Although few studies have been published with respect to barcoding, the majority reveal that the cytochrome c oxidase 1 (CO1) gene, used in isolation or in conjunction with other molecular markers, can greatly benefit South African biodiversity research. Several limitations of DNA barcoding are discussed and recommendations specific to South Africa provided.
Globally, amphibians are among the least appreciated vertebrates and are often negatively perceived by the general public. Such attitudes are particularly prevalent in South Africa, where fear, superstitions and myths associated with frogs are pervasive in some cultures. These attitudes could have harmful consequences both for the animals concerned and conservation efforts. This study aimed to investigate attitudes to frogs throughout South Africa across multiple age and ethnic groups. We used a multi-language survey in both hard-copy and online versions. Respondents (n = 2 295) comprised both genders across six age groups and five ethnic groups. A functionalist approach using structural equation modelling was used to assess how liking of frogs and cultural beliefs varied with socio-demographic factors. Attitudes varied significantly between groups, with males more likely to like frogs than females and age and level of education also significantly linked to liking. The influence of cultural beliefs and lack of knowledge also directly influenced negative attitudes towards frogs. More than 60% of respondents expressed an interest in learning more about frogs, indicating an opportunity for improving attitudes through educational outreach. The findings of this study can be used to inform current efforts to protect amphibians in South Africa through social interventions.
Lilian's Lovebird Agapornis lilianae is a non-excavating cavity user of mopane Colophospermum mopane woodlands. We investigated roost characteristics of Lilian's Lovebirds in Liwonde National Park, Malawi. We quantified tree and roost site variables for roost and non-roost trees. Sixty-six roosts were found. Roosts were in large tall mopane trees with a mean diameter at breast height (dbh) of 57.4 ± 1.64 cm, a mean height of 16.5 ± 0.42 m, and with a mean cavity entrance height of 10.0 ± 0.05 m. Non-roost areas had significantly smaller trees (mean dbh = 39.4 ± 1.72 cm). Human disturbance was low in both areas, but browsing of African elephant Loxodonta africana was evident by large areas of stunted mopane woodland recorded in non-roost areas. We recommend that the current Liwonde National Park vegetation map be updated to highlight areas of stunted mopane woodland unsuitable for Lilian's Lovebird roosts. The impact of elephant browsing on large mopane trees should be assessed to understand its impact on the availability of suitable cavities for lovebirds and other tree cavity reliant vertebrate species.
The burrow architecture (length, internal dimensions, fractal dimension of tunnel systems, number of nesting chambers and surface mounds) was investigated in the Damaraland mole-rat (Fukomys damarensis). A total of 31 animals were caught from five different colonies and their burrow systems were excavated in their entirety. The mean and SD colony size was 6 ± 3.3, with a range of 2–10 mole-rats. The sex ratio tended to be male biased 1.21:1. Males had a body mass of 80.5 ± 33.8 g, but were not significantly different to those of females, which had a mean body mass of 83.4 ± 24.9 g. The burrow system of the Damaraland mole-rats follows the same general architectural plan as recorded for other species of mole-rat with either one or two more centrally based, deeper, more permanent burrows that often connect to a nest area, which is used for resting and rearing offspring. The burrow systems contained several more superficial secondary tunnels at a shallower depth. The secondary tunnels accounted for up to 80% of the total burrow system. The mean length of the burrow system was 130 m and covered an area of 1 403 m2. The mean number of secondary branches in a burrow system was 10. The mean fractal dimension was 1.15, which implies the mole-rats do not explore their surrounding environment particularly efficiently when compared with that of other mole-rat species, but this may relate to the size of the main food resource, the Eland bean (Elephantorrhiza elephantina), which is randomly distributed and fed on in situ. Our study showed that colony size influences the size and complexity of the burrow system, with larger colonies having a longer burrow system covering a greater area with more secondary tunnels than that of smaller colonies.
Black-backed jackals (Canis mesomelas) are an abundant mesopredator on farmlands (croplands and rangelands) across South Africa. Given their adaptability in a changing anthropogenic landscape, knowledge of spatial movements can provide important ecological information on the species. We captured, collared and monitored five black-backed jackals in the Midlands of KwaZulu-Natal to determine their home range and habitat use in farmlands. The 95% fixed kernel (95% FK) home range sizes were large, showing a marked seasonal variation in movement. One adult male dispersed 150 km over two seasons (winter and spring) and thereafter settled into a home range that it maintained. Transient home ranges of males and juveniles were larger than resident home ranges. The mean resident home ranges (95% FK) across seasons for adult males, adult female and juvenile males were 11.4 ± 4.3 km2, 5.6 ± 0.36 km2 and 2.15 ± 0.45 km2, respectively. The mean transient home ranges (95% FK) of all the seasons for adult and juvenile males were 1 181.93 ± 575.81 km2 and 104.27 ± 35.64 km2, respectively. Adult jackal preferred croplands in spring, summer and autumn but avoided croplands in winter. Variable habitat use and large home ranges in our study confirmed the species' ability to adapt to agricultural areas.
Measuring physiological stress reactions through the quantification of plasma cortisol often involves physical restraint, which acts as a stressor itself. Here, we present the validation of a non-invasive method for assessing adrenocortical activity as an indicator of stress in the bat-eared fox (Otocyon megalotis). By conducting an adrenocorticotropic hormone (ACTH) challenge, we examined the suitability of three enzyme immunoassays (EIAs) detecting 11,17 dioxoandrostanes (11,17-DOA) as well as faecal glucocorticoid metabolites (fGCM) with a 5β-3α-ol-11-one (3α,11oxo-CM), or 11,17,21-trihydroxy-4-ene-20-one structure (cortisol), respectively, for monitoring stress-related physiological responses in male and female bat-eared foxes. Our results suggest that the cortisol EIA seems most suitable for measuring fGCMs in this myrmecophageous mammal. Using the cortisol EIA, we compared fGCM concentrations of three populations of foxes. Only one population experienced a sudden change in social environment and the assay appeared to effectively detect the expected resulting increase in stress hormone levels. Therefore, the identified EIA is effective at detecting intraspecific variation in fGCM levels and hence is a useful tool to evaluate physiological stress responses in this species.
Debate regarding the biological effect of electromagnetic radiation has been recently raised. The effects of this radiation on locomotor activity are not well known. Hence, in this study, we used Drosophila melanogaster as a model organism to investigate the possible effects of short-term exposure to ringing or talking cellphone modes on locomotor activity. Interestingly, an hour exposure to the cellphone ringing mode did not significantly affect the fly movement speed in the negative geotaxis assay. However, the flies exposed to sending or sending—receiving ringing modes showed disturbed movement paths compared with control flies. To verify these results, third-instar larvae were tested using a crawling assay. The larvae exposed to emissions of 1 h sending-rings tended to crawl in short, random and scattered paths, whereas control larvae crawled parallel to the wall of the petri dish. On the other hand, exposure to the cellphone talking mode induced significant reduction in the movement speed of adult Drosophila. The speed of flies exposed to sending mode showed a negative regression with the time of exposure. The flies exposed to receiving-talk mode were significantly slower than the controls at all tested time intervals. Furthermore, the flies exposed to 1 or 2 h sending-talks exhibited irritated zigzag locomotor paths and hyperactivity. The results suggest that prolonged exposure to signalling cellphone electromagnetic radiation may exert locomotor disorders as evident by significant alterations in the neuro-behavioural events related to locomotor equilibrium of D. melanogaster.
The practice of catch-and-release fishing has been widely promoted by angling fraternities as a fisheries management tool. The aim of this investigation was to determine the physiological response of Orange-Vaal smallmouth yellowfish, Labeobarbus aeneus, to catch-and-release angling in the Vaal River, South Africa. Fish were collected using standard fly-fishing techniques, anaesthetised in clove oil and blood was drawn from the caudal vein; thereafter the fish were weighed, measured, revived and released. Blood plasma was analysed for concentrations of glucose, cortisol and lactate to determine the effects of angling duration, fish size and water temperature. Larger fish were angled for a longer duration compared with smaller fish. Levels of glucose were affected by water temperature (influenced by time of year). Plasma glucose concentrations decreased with greater angling duration. Few individuals (n = 12) showed increased plasma cortisol concentrations. In extended-capture fish (angled for >1 min), lactate concentrations increased significantly above values for rapid-capture fish (angled for >30 s). These data suggest that catch-and-release causes physiological stress to fish, but nonetheless this practice can be a valuable fisheries management tool to ensure the sustainability of fish populations. Other factors beyond the ‘angling’ time are likely to contribute to physiological disruptions in homeostasis and therefore handling and air exposure of angled fish should be included in future catch-and—release angling studies. In addition, the longer-term impact of angling on fish health should also be determined.
DNA barcoding has been proposed as a method for species identification. However, this method has been criticised for its over-reliance on a single mitochondrial gene. In this study, four mitochondrial gene regions and one nuclear gene region were used to investigate their different abilities to identify tissue associated with museum specimens of Aethomys chrysophilus, Aethomys ineptus and Micaelamys namaquensis. Aethomys chrysophilus and the more recently elevated A. ineptus are indistinguishable on morphological grounds; however, their ranges are largely parapatric with only one syntopic locality currently known. All of the mitochondrial gene regions were able to separate M. namaquensis from A. chrysophilus and A. ineptus, but they varied in their abilities to resolve differences between A. chrysophilus and A. ineptus. The sequence results identified a specimen from KwaZulu-Natal that was misclassified and should have been identified as A. ineptus. Seven specimens that had not been reclassified following the elevation of A. ineptus to species level were identified as A. ineptus. Individuals of A. chrysophilus from Malawi could not be classified as either A. chrysophilus or A. ineptus, and may be a hybrid or a new, distinct species. This study indicates that DNA barcoding may be used to separate M. namaquensis from A. chrysophilus and A. ineptus, and although it was not able to separate A. chrysophilus and A. ineptus, it did indicate specimens from Malawi may be a new cryptic species.
This article is only available to subscribers. It is not available for individual sale.
Access to the requested content is limited to institutions that have
purchased or subscribe to this BioOne eBook Collection. You are receiving
this notice because your organization may not have this eBook access.*
*Shibboleth/Open Athens users-please
sign in
to access your institution's subscriptions.
Additional information about institution subscriptions can be foundhere