First letter: This Letter to the Editor, as well as the companion Letter to the Editor (African Zoology 49(1): 2–4, 2014) and Short communication (African Zoology 47(2): 353–357, October 2012) that it implicates/refers to, have been retracted by the Editors-in-Chief and neither the electronic nor the print version of the short communication or the letters should be cited.

Second letter: This Letter to the Editor, as well as the companion Letter to the Editor (African Zoology 49(1): 1–2, 2014) and Short communication (African Zoology 47(2): 353–357, October 2012) that it refers to, have been retracted by the Editors-in-Chief and neither the electronic nor the print version of the short communication or the letters should be cited.

Surf-zone fish communities and their shifts over time are generally poorly understood. The aim of this study was to compare the current surf-zone fish assemblage at King's Beach, South Africa, to a similar study conducted three decades ago, before the collapse of many exploited shore fishes in the region. Beach seine nets (mesh sizes of 10 and 50 mm) were used to target juvenile and adult fishes bimonthly from February to August 2011 over the high tide around sunset. A total of 14 species were recorded in both the 30 m and 100 m seine nets. The catch in these seine nets was dominated by Pomadasys olivaceus and Liza richardsonii, and this was significantly different to three decades ago, when P. olivaceus, Sarpa salpa and Diplodus capensis dominated the catch. Important linefish species belonging to the Sparidae and Sciaenidae families were significantly smaller and less abundant in this study. Two sparids, S. salpa and Lithognathus mormyrus, which made a large contribution to the surf-zone catch three decades ago were absent during this study. Reasons for the significant shifts in the surf-zone fish community, including overexploitation of the linefish and potential habitat modification, are discussed.

Differences in nectar characteristics of bird-pollinated plants were originally attributed to whether the plant was pollinated by non-passerine hummingbirds or passerine nectarivores. Subsequently this has been refuted and it is now hypothesized that these differences reflect whether the plants are pollinated by occasional or specialist nectarivores (feeding niche hypothesis). The volumetric intake, sugar preference and sugar concentration preference of the Cape white-eye (Zosterops virens), a small occasional nectarivore that also feeds on fruit and insects, was determined. This was done over a range of concentrations of both hexose and sucrose sugars using equicaloric solutions in pairwise choice tests. Birds exhibited no significant sugar type preference at any sugar concentration, but showed a preference for the lowest concentration (10%) of both hexose and sucrose solutions when presented with a range of sugar concentrations. The birds were able to meet energy demands on a dilute diet by adjusting volumetric intake and did not lose body mass. A significant preference for the 10% hexose and sucrose solutions may suggest that these occasional birds exert a selective pressure on the plants they pollinate to produce dilute nectar.

The effects of collecting prawns (Callichirus and Upogebia spp.) in Langebaan Lagoon as bait were assessed in 1999–2001 and in 2012–2013. Langebaan Lagoon (part of West Coast National Park and a Marine Protected Area) is divided into three zones. One zone is a sanctuary, a second allows non-extractive visitation, and the third is for general use including bait collecting and fishing. In 1999–2000, the number of people visiting the sandflats to collect bait was highest during summer weekends ( = 48 per day), and was concentrated at two sites: Centre Banks and Klein Oesterwal. Callichirus kraussi was the main species harvested, with an estimated 1 008 178 being removed annually. This represents 0.12% of the sandprawn stock at Centre Banks and Klein Oesterwal, and 0.012% of the estimated total stock. In 2012–2013, total bait-collecting activities had increased 23% compared with 1999–2000, but still constituted a small proportion of the stock. On average, each bait collector removed 86 prawns per outing: 36 more than the legal daily limit. The amount of sediment disturbed annually by bait collecting was estimated as 6189 tonnes. The surface area trampled by bait collectors and associated persons amounted to ∼562 800 m². Thus, although the proportion of C. kraussi harvested constitutes no threat to the stock, associated disturbance has local adverse effects on the ecosystem.

For spiny mice, detailed long-term data on reproductive endocrine function is lacking, as limited blood volumes make frequent collections of individual plasma samples for hormone monitoring impractical. To provide the necessary tools in order to fill this gap, this study examined the suitability of two enzyme immunoassays for monitoring male and female reproductive function in the southern African spiny mouse (Acomys spinosissimus) based on faecal hormone analysis. Fourteen non-pregnant and one pregnant female and 24 male spiny mice were wild-caught and subsequently monitored under controlled conditions. Thirteen of the 14 non-pregnant females revealed elevated faecal progestagen metabolite concentrations with eight individuals showing indications of a luteal phase. Two females showed two post-ovulatory luteal phases with estimated cycle lengths of 16 and 18 days, respectively. The pregnant female had an elevated (231%) mean faecal progestagen metabolite level compared with the overall mean baseline hormone concentration determined for the 14 non-pregnant females. Males exposed to a long photoperiod, simulating summer-related breeding activity, exhibited a 47.8% increase in faecal androgen metabolite levels compared with males exposed to a short photoperiod. Collectively, the data demonstrated that reproductive endocrine function can be monitored in male and female spiny mice by measuring respective faecal hormone metabolites.

Systematists have not often made use of avian vocalizations to assess the taxonomic rank of birds, or to infer their phylogenetic relationships. The likely reasons for this stem from the perceived inability to distinguish genetic and ecological components of variation in vocalizations, the difficulty in detecting homology across taxa, as well as the diverse selection pressures acting on vocal characters which may make such characters particularly prone to convergent evolution. In this study, we scored and analysed DNA and vocal characters of two delineated assemblages of gamebirds, francolins and spurfowls. Our phylogenetic results suggest that short strophes evolved from longer strophes among taxa within the genera Scleroptila and Peliperdix. More generally, our results corroborate the francolin-spurfowl dichotomy, with francolin calls generally being long and tonal, containing a series of discrete elements that have detectable harmonics. In contrast, most spurfowls render short, atonal calls with elements that generally have no harmonics, although they may contain discrete elements. Phylogenetically, Ortygornis sephaena is placed with ‘true’ francolins and its closest relatives are the two phylogenetically enigmatic Asian francolins, the grey francolin, Ortygornis pondicerianus, and swamp francolin, O. gularis.

We present data from gut content analyses of Varanus albigularis (savanna monitor) and V. niloticus (water monitor) in South Africa. Both species are generalist, opportunistic feeders. We did not detect any sex-based differences in the diet of V. albigularis, and there were relatively high levels of dietary overlap between the species, although there were significant differences for certain prey types. These differences match differences in habitat use between the species: the more aquatic V. niloticus consumed aquatic prey, such as amphibians and crabs, more often than did V. albigularis. Varanus albigularis included more terrestrial prey such as diplopods in its diet. Tortoises and millipedes were also prominent in the V. albigularis diet, constituting an important component of dietary intake. Few of our samples from V. albigularis had empty stomachs, suggesting that this species may occupy a lower trophic level than its Australian counterparts. Although there is a large degree of overlap in the diets of the two species, there is a trend for V. albigularis to eat more slow-moving prey. These differences result in the species foraging at different trophic levels.

The African wild silk moth (Gonometa postica) exhibits large inter-annual population size fluctuations in the Kalahari region of southern Africa. Spent cocoons from this species are currently being utilized in a local silk industry. An understanding of the recolonization dynamics of a particular harvested site, and of the population genetic effects of such dispersal, are crucial for designing a scientifically-based harvesting strategy. I link morphological estimates of flying ability to microsatellite genotyping in the determination of dispersal ability of this species. Morphological results suggest that the moth is a poor disperser with high wing loadings and males are better fliers than females. There is a significant effect of isolation-bydistance. Spatial population genetic analyses of microsatellite data further indicate lower and upper bounds on dispersal of 90 m and 50 km. The combined evidence suggests male-biased dispersal over several dozen kilometers with females that do not disperse over large distances. I discuss the potential influences of large population size fluctuations on patterns of genetic diversity and the implications for the inference of dispersal in my study species.

The Cape gannet, Morus capensis, has long been considered a monomorphic species despite attempts at phenotypically separating the sexes. In a further effort we here recorded morphometric measurements from genetically sexed Cape gannets. Discriminant function analysis was used to classify sexes according to these morphometric measurements. Culmen and gular stripe lengths were selected as the best discriminators, correctly classifying 65% of birds. Male Cape gannets had significantly longer culmens and gular stripes than females. We thereby provide the first evidence suggesting that the Cape gannet demonstrates some level of dimorphism. Nonetheless, morphometric criteria used to separate sexes holds limited value due to overlap in measurements between sexes.

This paper provides a description of the zooplankton and epiphytic diatom communities of permanent and temporary freshwater pans in the Mpumalanga Highveld region of South Africa. Few studies have investigated the biota of pans in this area, which is seriously threatened by mining and agricultural development. Nineteen pan sites within a 20 km radius covering a wide range of water chemistries were sampled once for zooplankton, epiphytic diatoms and water physico-chemical data in 2009. Collected zooplankton and diatom samples were identified to species or genus level. Many of the zooplankton taxa reported in this study were not recorded in similar pan studies in South Africa and southern Africa. The study revealed a difference among the compositions of zooplankton and diatom communities between temporary pans and permanent pans. Zooplankton found exclusively in freshwater temporary pans included cladocerans (Megafenestra aurita and Scapholeberis kingi), calanoids (Mesocyclops major and Thermodiaptomus mixtus), a cyclopoid (Acanthocyclops vernalis) and a rotifer (Platyias quadricornis). Permanent pans were characterized by taxa such as cladocerans (Ceriodaphnia rigaudi and Dunhevedia crassa), a calanoid (Metadiaptomus transvaalensis), cyclopoids (Paracyclops fimbriatus and Eucyclops gibsoni) and rotifers (Brachionus dimidiatus and Brachionus plicatilis). The most commonly occurring diatom taxa in temporary pans included taxa indicative of slightly acidic to circumneutral, dystrophic and nutrient-poor waters such as Nitzschia acidoclinata, Gomphonema gracile and Eunotia bilunaris. Permanent pan assemblages were characterized by taxa typical of saline waters, including Nitzschia frustulum, Amphora veneta and Planothidium engelbrechtii. Species of the genera Pinnularia and Eunotia were almost totally absent from permanent pans.

Despite the unique gonadal organization and reproductive strategies known for elasmobranchs very little is known about the reproductive biology of local species. The stages of spermatogenesis for the lesser guitar fish, Rhinobatus annulatus, has not been described and specifically the mechanism for sperm release from the spermatosyst was until now not known. The elongated paired testes, consisting of dome-shaped lobules, were embedded in an epigonal matrix. The lobules consisted of spherical spermatocyst, containing the spermatogenic cells arranged in concentric layers. In each spermatocyst, germ elements were in the same stage of differentiation. Discharging of sperm was found to be conveyed via a ciliated ductule system. The excurrent duct system consisted of the vasa efferentia, epididymis, vas deferens, seminal vesicle and cloaca. Seasonal reproductive activity was evident when the gonadosomatic index reached a maximum in November and a minimum in May. Ripe running males were observed from January to June. Mating took place between April and June. Sexual maturity was reached at a total body length of 580 mm and at three years of age. Knowledge of size/age at sexual maturity and seasonal reproductive activity in the local elasmobranch, Rhinobatus annulatus may prove critical to ensure effective management and conservation strategies for this species.

Many animals emit alarm calls in response to a potential predator. These calls may transmit information about predator type and response urgency. This study compared the alarm calls of the social buff-streaked chat, Oenanthe bifasciata, to the asocial African stonechat, Saxicola torquata. Spring traps were used to capture birds in the foothills of the Drakensberg Mountains, and pairs and groups were housed separately in outdoor aviaries. Both species were exposed to latex snakes and raptor models presented individually at 1 m, 5 m and 10 m respectively, while alarm calls were recorded. Analyses of the acoustic variables revealed that both call rate and duration decreased when the predator was further away. Larger groups of buff-streaked chats increased their raptor alarm call rate (39 calls in five minutes) and reduced the frequency of their end-pulses (for both predators) by 0.6 kHz. Hence, large groups present a louder, perhaps more formidable mob to discourage attack; softer end-pulses may minimize cues to the callers' location, and higher call rates during high-risk situations reflect the response urgency required to escape aerial predation. African stonechats were quieter, a strategy, perhaps, to reduce detection. Group size may therefore influence the perception of threat, where larger and louder groups become more conspicuous for aerial predation.

The Damaraland mole-rat (Fukomys damarensis) is a social, subterranean rodent that occurs in the red Kalahari sands. This species exhibits extreme reproductive skew with a single breeding female whereas reproduction in subordinate group members is completely blocked. Rainfall, as it greatly facilitates burrowing, provides the opportunity for individuals to disperse from their natal colony and hence, to overcome reproductive suppression. However, because rainfall is scarce, optimal conditions for burrow system construction are restricted to very short periods of the year. In order to observe the construction of a new burrow system of dispersing individuals, I released a small group (two females, one male) following heavy rains, and monitored their burrowing activity in the form of mound production during the following weeks. Recapture revealed that a new male had joined the group. Over a period of one month the four individuals extruded 127 mole hills and constructed a tunnel system with a total length of approximately 100 metres. Mound production ceased after 30 days due to the lack of subsequent rain. The study provides an example of dispersal in Damaraland mole-rats and gives new insights into the method of burrow system construction of this species. It further highlights the high costs associated with dispersal.

Guinea fowl is a common game bird in Africa and there have been efforts to domesticate it for use as a source of human food. An important obstacle in successful domestication of guinea fowl is their low fertility rate. We studied the effects of semi-confinement on the fertility rates of helmeted guinea fowl by comparing egg fertility, hatch rate and keet survival rates in a wild (WL) and a semi-confined (SC) group. We undertook the study in Eastern Kenya for a period of 16 months that represented three breeding cycles. There was no significant difference (P > 0.05) in egg fertility rates between egg laying cycles in the SC group. However, the egg fertility rate of the WL group was significantly higher (P < 0.05) than that of the SC group. There were no significant differences in the hatch rate of eggs (P > 0.05) or the keet survival rates between the WL and SC groups. These results clearly show that low egg fertility rate is a key limiting factor in the reproductive success of helmeted guinea fowl kept in semi-confined spaces

Meriones shawi is an ubiquitous and endemic rodent in northern African. This species is considered as an economically important pest because it often damages crops. Moreover, the gerbillines are known to function as reservoirs for a variety of serious human epidemic diseases. Ten polymorphic microsatellite loci were identified using 454 GS-FLX Titanium pyrosequencing and a multiplex PCR assay was developed. The utility of these markers was evaluated in 30 individuals from three different Moroccan populations. Number of alleles per locus ranged from 2 to 7, with observed and expected heterozygosities ranging from 0.033 to 0.967 and from 0.033 to 0.729, respectively. Departures from Hardy-Weinberg equilibrium were observed at two loci. These markers will be useful resources for future population genetics studies for this rodent and pest-borne disease management.

Wahlberg's epauletted fruit bat, Epomophorus wahlbergi, feeds on a range of fruit, nectar, pollen and flowers. Frugivores may have difficulties in maintaining their protein requirements since fruit are generally high in sugar content but low in protein content. Some studies have found that fruit bats obtain most of their food protein when feeding on a variety of fruits. We investigated if E. wahlbergi prefers additional protein to sugar-only nectar solutions. They were offered equicaloric 15% glucose solutions with varying protein concentrations (2.58, 5.68, 7.23 g soy protein/kg H₂O) and a solution with no protein. This was repeated using 15% sucrose instead of glucose solutions. Epomophorus wahlbergi's volumetric intake of the respective glucose and sucrose solutions varied among individual bats, with total volumetric intake being highest for solutions with no protein. This suggests they have low protein dietary requirements, which may be a response to the low-protein fruit available in the wild. Alternatively they may supplement their diet by actively preying on insects, but this needs to be investigated.