A literature review reveals that reproductive seasonality of less than 1% of South Africa's inshore marine invertebrates has been studied. Approximately 95% of studies have been on large, long-lived, gonochoristic, iteroparous species, and nearly 50% on molluscs. There is only a weak relationship between biogeographic region and timing of reproduction, Nevertheless, a relatively large proportion of west coast species studied breed in winter, whereas south coast species tend to have breeding peaks in spring/summer, although many nearly always have mature gametes and probably reproduce year-round. East coast species are mainly continuous or summer breeders, The factors that control gametogenesis and trigger spawning are largely unresolved, although temperature and food are thought to be important in many species.

One function of aggression in animals is to gain access to mates. Aggression may therefore be favoured by sexual selection, the strength of which can be assessed using repeatability of aggressive behaviour. Here, we tested the hypotheses that male swordtails, Xiphophorus sp., are consistent in the aggressive and mating behaviours exhibited and in the time spent at a close distance to females (female attendance), and that aggressive males gain increased opportunity to attempt copulation compared to their less aggressive conspecifics (sneak frequency). As predicted, aggression between males, and male display and sneak frequency were repeatable. However, male aggression was not significantly correlated with sneak frequency. The function of aggression in this species is not clear-cut and may have an indirect female access function through formation of dominance hierarchies or defence of resources. A surprising finding highlighted by this study was the contradictory results for consistency in female contact, with high repeatability scores indicating consistency in behaviour but the within-subjects component of repeated measures ANOVA showing differences in female contact between trials. The possible reasons for this discrepancy are discussed.

The rock-dwelling cichlids in Lake Malawi comprise the most diverse freshwater fish community in the world, Individuals frequently interact with heterospecifics through feeding territoriality. Underwater observations and experiments were conducted to examine interspecific variation in the frequencies of territorial behaviour and its influence on the feeding habits of heterospecifics. Frequencies of chasing and fleeing associated with interspecific territoriality were remarkably different amongst 10 cichlid species. In addition, individual fish that attacked heterospecifics more frequently were attacked less often by them, suggesting that interspecific interactions amongst cichlid species are asymmetric, The experimental removal of territory owners belonging to the most aggressive species resulted in almost fivefold increase in feeding within territories, suggesting that territorial aggression preserves food resources for the territory holder and influences the feeding habits of other species, including those with some dietary dissimilarities. Additional information regarding asymmetric interspecific interactions would improve understanding about how diverse cichlids within trophic groups manage to coexist.

Lake Tana harbours the only known intact species flock of large cyprinid fishes (15 Labeobarbus spp.). One of the most curious aspects of this species flock is the large number (8) of piscivorous species. Cyprinids are not well designed for piscivory (i.e. small slit-shaped pharyngeal cavity, lack of teeth in the oral jaws, lack of a stomach), which raises the question how well adapted these labeobarbs actually are to function as piscivores? In this study we analyse the kinematics of prey capture (by varied combinations of suction, swimming and jaw protrusion) among Lake Tana's piscivorous labeobarbs. Suction feeding kinematics were similar to values reported for other piscivorous fish species. A detailed analysis of several Labeobarbus species displayed distinct types of techniques (overswimming, velocity/volume suction with jaw protrusion) suited to capture elusive prey in different macro-habitats, Lake Tana's Labeobarbus species evolved a wide range of piscivorous predation techniques, a unique scenario for cyprinid fishes.

The effect of temperature (15 and 25°C) and salinity (15 and 35 practical salinity units) combinations on the growth and longevity of the South African estuarine isopod Exosphaeroma hylocoetes was investigated and data analysed using the logistic growth model. No significant differences (P = 0.43 to 0.54) were obtained for the growth rates of male and female E. hylocoetes under the suite of temperature/salinity combinations. Among the variables considered, temperature was identified as the most important in influencing the growth rates of the isopod. Elevated temperatures promoted faster initial growth in both males and females. Salinity had no significant influence on the growth rates of males and females. Males (25.77 ± 3.40 weeks) lived significantly longer (P < 0.001) than females (21.52 ± 3.00 weeks), allowing males (8.08 ± 0.25 mm mean body length) to attain a significantly larger size than females (6.59 ± 0.25 mm) under experimental conditions. Females, however, attained sexual maturity (at 2.5 mm body length) 2–4 weeks earlier than males (5.5 mm in length). It is suggested that the faster growth rates at the higher temperature/salinity combinations allow the isopod to reach sexual maturity at an earlier stage than those at the lower combinations.

Translocated oysters are well known to act as vectors of marine alien species, but to date this topic has received scant attention in South Africa, despite the fact that oysters have been imported into this region since 1894. Surveys of oyster farms in South Africa revealed four newly-recorded alien species: the black sea urchin, Tetrapygus niger, from Chile; the European flat oyster, Ostrea edulis (thought to be extinct since its intentional introduction in 1946); Montagu's crab, Xantho incisus, from the North Eastern Atlantic seas of Europe, and the brachiopod Discinisca tenuis from Namibia. Oyster imports are the most likely vector of all these species. The biological attributes of each species, the possible threats posed by their introduction, and the needs for additional control measures to limit or prevent further introduction and spread of alien species via oyster culture are discussed.

The larval fish assemblage was investigated in the permanently open Nxaxo-Ngqusi Estuary Complex, situated in the subtropical—warm temperate biogeographic boundary zone of South Africa. Larval and early juvenile fishes were collected in summer and winter of 2007 and 2008 using a mixed method approach by boat-based plankton tows in mid-channel waters and seine net hauls along the margins. In total, 20 455 fishes were collected representing 21 families and 40 taxa, of which 13 900 fishes were from mid-channel sites (15 families and 21 taxa). Seine net hauls along the estuary margins produced 6550 fishes representing 18 families and 33 taxa. Gobiidae was the dominant fish family in the mid-channel waters followed by the Clupeidae whereas the opposite was found in marginal waters. Estuary-resident larvae were the dominant group in the estuary complex. The catches typically reflected a more warm-temperate community, although subtropical-associated species were present. Fish density in mid-channel waters was higher in the Ngqusi arm than that of the Nxaxo arm, whereas along the marginal waters, CPUE was higher in the latter. Fish densities in mid-channel waters and CPUE along the margins were typically higher in summer.

Photo-identification surveys over three years along 390 km of coastline north of Cape Town, revealed that Heaviside's dolphin distribution was consistent between years and higher in areas more exposed to swells and with greater long-term availability of small hake Merluccius capensis (their principal prey). Dusky dolphin sighting rates varied considerably between years, but were generally higher in areas with lower hake availability and sandier shores (mostly straighter coastline). Large groups of 50–200 dusky dolphins were only seen in St Helena Bay the site of a wind-driven upwelling zone. Heaviside's dolphins were found in shallower, cooler water than dusky dolphins and were more likely to be seen during brighter phases of the moon (when nocturnal light conditions may influence the vertical migration patterns of prey) and in areas of high hake abundance, Near-shore fishing activity was higher in the northern half of the study area and clustered around harbours. Set netting occurred only at Yzerfontein and St Helena Bay, but due to changes in the industry is currently thought to be a low threat to the population. Interactions between Heaviside's and dusky dolphins were usually neutral and sympatry appears to be mediated by differences in overall range and the type and size of prey species taken.

Two species of echiurans (Echiura), Anelassorhynchus semoni (Fischer, 1896) and A. mucosus (Ikeda, 1904), were collected from the intertidal rocky shores at Perriers Rock on the Kwazulu-Natal north coast, This is the first known record of these species from South African waters, Anelassorhynchus semoni was originally described from two specimens from Indonesia. It was later recorded from the Maldive Islands and from the coast of West Africa in the North-East Atlantic in the vicinity of Senegal. The original description of A. mucosus is based on three specimens from Moroiso, Misaki Marine Station, Japan. It was later recorded from Korea. The discovery of these two species of echiurans from the east coast of South Africa considerably extends their geographical ranges. Both species are briefly redescribed and some of the taxonomic characters are reviewed. Key words: new records, echiurans, Anelassorhynchus semoni, A. mucosus, South Africa.

Reptiles have an amazing diversity of life-history attributes ranging from the shortest- to longest-lived of vertebrate species. Estimating survival in wild populations is of key importance when understanding population dynamics and life-history evolution. However, data are lacking for a large and charismatic group of lizards, the chameleons. We conducted a Robust Design (RD) capture—mark—recapture (CMR) experiment on the Cape dwarf chameleon, Bradypodion pumilum, at two nested sites within the Cape Town Metropolitan Area, South Africa, in order to estimate survival and movement of adults in and around an isolated 3.5 ha patch of suitable habitat. Over a nine-week period, 97 individuals were identified in 379 captures from five primary capture sessions with three secondary events each. Analysis of CMR data provided evidence that smaller chameleons have a substantially lower survival per 10-day period than larger chameleons. RD analysis showed that males were more prone to temporary emigration than females, while open multi-strata analysis revealed that smaller chameleons more readily moved between the sites than larger chameleons. Our findings offer first important insights into chameleon survival and life-history dynamics, which suggest a more vagile subadult population and the possibility of male biased dispersal. Our results have implications for managing the conservation of threatened chameleon populations in highly fragmented urban habitats.

A systematic classification of Namib Desert darkling beetles (Coleoptera: Tenebrionidae) based on morphological characters is complicated as strong selection pressures exerted by desert conditions have led to a suite of convergent morphological characteristics. Here we present a first and preliminary insight into the relationships within the tribes Zophosini, Eurychorini and Adesmiini using molecular methods. We analysed partial sequences of the mitochondrial genes cytochrome oxidase II and cytochrome b of 16 individuals comprising 12 species. Minimum Evolution, Maximum Parsimony, Maximum Likelihood and Bayesian inference were applied for analysing sequence data. The genus Pimelia was used as outgroup and for calibrating divergence time estimates. Overall, results supported phylogenies constructed on morphological characters. The proposed monophyly of the artificially defined tribe Zophosini did receive sufficient support, Speciation events in Namibian darkling beetles likely occurred during periods of aridification about 35 Mya, 16 Mya and 5–10 Mya. Those periods could be related to geological events and climate change due to the glaciation of Antarctica and the development of the Benguela current.

The diet of three populations of semaphore geckos (Pristurus) from Socotra archipelago is analysed based on 82 faecal pellets. Pristurus samhaensis from the small islands of Samha (n = 18) and Darsa (n = 24) and P. sokotranus from the main island of Socotra (n = 40) were compared, Like other Pristurus species, P. samhaensis on Samha and P. sokotranus on Socotra were highly myrmecophagous (76,7% and 38.6% ants, respectively), However, ants were absent from the diet of P. samhaensis on Darsa. In contrast to the rich native ant fauna of the other islands, only one ant species was reported for Darsa, Pheidole teneriffana, likely a recently introduced species. Pristurus samhaensis seems to have overcome this scarcity in ant prey by consuming substitute prey, namely Coleoptera and Heteroptera, which are secondary for the other two populations studied. The two P. samhaensis populations inhabiting the small islands displayed less diverse diets compared to that of P. sokotranus from the main island where vegetation structure was more complex. Prey items of P. samhaensis from Darsa were also smaller than those of P. sokotranus from Socotra, those of P. samhaensis from Samha being intermediate. It remains unclear how ancient these differences are, but they are probably too recent to have promoted special morphological and ecological adaptations in these geckos.

The intraspecific variation of mitochondrial cytochrome b sequence was analysed for two widely distributed Tunisian anuran species, Discoglossus pictus and Pelophylax saharicus. We observed low genetic variation within both species (D. p. auritus 0.6% uncorrected genetic distances, P. saharicus 0.2%) and the absence of genetic structure within both species in the studied region. There is no correspondence between previously described morphotypes of P. saharicus in Tunisia and our genetic data. Our results show a lack of phylogeographic structure in both species despite their fragmented distribution across Tunisia.

During a survey of seals in September and October 2009 at Gough Island, South Atlantic Ocean, we recorded goose barnacles (Lepas australis) attached to the pelage of two of the 12 elephant seals (Mirounga leonina) inspected and one of the seven vagrant Antarctic fur seals (Arctocephalus gazella) which were found amongst the resident Subantarctic fur seals (A. tropicalis). We also recorded a goose barnacle attached to a Northern rockhopper penguin (Eudyptes chrysocome moseleyi).

We tested the hypothesis that growth zones in the astericus otoliths of smallmouth yellowfish (Labeobarbus aeneus) and Orange River mudfish (Labeo capensis) were deposited annually, Two methods, fluorochrome marking and edge analysis of otoliths were used. For fluorochrome marking, specimens of both species were injected with 60 mg/kg fish mass Oxytetracycline hydrochloride (OTC) and released into large earthen ponds under ambient conditions adjacent to Lake Gariep. Twenty-three L. aeneus and one L. capensis were recaptured 10–14 months later. Edge analysis was based on the optical interpretation of L. aeneus (n = 342) and L. capensis (n = 512) otolith margins collected between November 2006 and May 2008 from Lake Gariep. The frequency distribution of opaque margins over time was fitted using a binomial periodic regression. The estimated cycle length was not significantly different from a hypothesized 12 months for both species. The number of growth zones distal to the OTC mark was consistent with findings from the edge analysis, providing evidence that growth zones in astericus otoliths of both species can be interpreted as annuli.

Otolith microstructure analysis was used to validate microincrement deposition rate and to determine daily growth rates of young-of-the-year (YOY) Baringo tilapia, Oreochromis niloticus baringoensis. Micro-increment formation was validated as daily by correlating the number of circuli on otoliths with the known age of cultured fish. For wild young-of-the-year fish collected from Lake Baringo, Kenya, in August and October 2007 length was positively correlated with the age of fish (total length (mm) = 0.1187 age (/day) 1.1344 (r² = 0.97); standard length (mm) = 0.0964 age (/day) 0.7082 (r² = 0.97)) and growth rate was subsequently estimated at 0.12 cm/day.

An immature Subantarctic fur seal was sighted on Unguja Island, Zanzibar, Tanzania, in 2008. This is the most northerly record of a vagrant of this species. The nearest breeding colony is on the Prince Edward Islands, 4500 km distant, While it is likely that this is the natal site of the vagrant due to its proximity and population size, the actual location of origin is unknown. This is the second fur seal sighted in this area. A fur seal of unknown species was sighted on Pemba Island, 30 km north of the Unguja Island, in 2002. While the species of the latter animal could not be determined, it is likely also a Subantarctic fur seal.