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The recently described amphipod Sunamphitoe roberta lives only on the kelp Ecklonia maxima, where it excavates slit-like burrows along the distal margins of thicker primary fronds. Oval chambers along the bases of these slits may represent feeding areas. As burrowing proceeds, the damage progressively erodes back the frond margins, giving them characteristic attenuated and irregular profiles, and probably impacting secondary frond survival and growth, and hence kelp productivity. A kelp forest in False Bay, South Africa, was surveyed to determine what proportion of kelp was infected as well as which individuals were selected as hosts. Forty kelp heads were also dissected to ascertain numbers of amphipods per host and their size composition, and to document details of burrow structure. Of 305 adult kelps inspected, 117 (38.4%) showed visible amphipod damage. Rate of infestation was not correlated with stipe length but was positively correlated with head circumference and negatively correlated with the proportion of secondary fronds remaining. The 40 kelp heads dissected contained 786 S. roberta specimens. These comprised 154 adults (>8 mm), including 33 ovigerous females, and 632 juveniles (

South Africa has a long history of engagement in citizen science (CS), particularly marine CS. This review examines the contributions made by marine CS, from the 1930s through to the current era, where websites, social media and mobile apps provide a wide range of opportunities. Largescale marine CS projects, such as the Oceanographic Research Institute’s Cooperative Fish Tagging Project, have made enormous contributions to marine scientific research. Individual citizen scientists have also made considerable contributions, particularly in taxonomy and the publication of field guides. Marine CS has also contributed towards the popularisation of science and improved scientific literacy through the active engagement of many citizens. These benefits align well with the visions of policies that currently guide the South African marine research agenda. However, marine CS in the developing world is not without challenges, and practitioners should be cognisant of the time and effort required to initiate and maintain viable CS initiatives. Especially, long-term successful CS projects depend on secure, ongoing funding, institutional support and enthusiastic champions. Participation by almost exclusively the urban and middle-class sectors of society is also of concern. These challenges can be addressed through stakeholder-inclusive planning, development of novel methods that engage with broader sectors of society, and regular critical evaluations of CS projects. Where global projects on the intended taxa/subject of study already exist, it may also be preferable to enter into collaborative data-sharing agreements with these to reduce operational costs and avoid duplication.

The edible beaked clam Eumarcia paupercula (Holten, 1802) is an abundant component of the intertidal infauna in Maputo Bay, Mozambique, and is an important source of food and income for local communities. This study investigates the population structure and estimates the growth rate of E. paupercula on a highly exploited tidal flat. Between November 2012 and April 2014, population structure was tracked by monitoring monthly length and density distributions, and growth rate was estimated using both mark-recapture experiments and length-frequency analysis (LFA). The population structure can be polymodal, bimodal or unimodal, as new cohorts of clams recruit to the population and older ones are fished or die out. The von Bertalanffy growth function Lt = 40.5 [1 – e–1.65(t – 0.03)] revealed that E. paupercula has a fast growth rate, equivalent to a phi-prime index (φ′) of 3.43, and a short lifespan of 1.97 years, similar to those of most other tropical venerid species. This article highlights that temporal population dynamics are strongly influenced by collection and reproductive patterns, and that single environmental parameters do not explain the patterns of growth. Understanding these factors will greatly facilitate development of management measures aimed at ensuring future sustainable exploitation of this species.Keywords: clam fishery, length-frequency, life history, marine invertebrate biology, mark-recapture, size distribution

The Palmiet Estuary is a small, rural estuary in the Western Cape that only closes briefly during dry summers. The system was previously surveyed during 1979 to 1980 and we repeated the survey in April 2015 (mouth closed) and September 2015 (mouth open). Salinity, temperature, pH and oxygen saturation were measured, and invertebrate and fish faunas surveyed. Physico-chemical characteristics have undergone little directional change, apart from an apparent increase in pH, possibly as a result of changes in land use and application of fertilisers and pesticides in the catchment. Invertebrate species richness increased from 31 to 40 species, despite lower sampling effort in 2015. Most changes were among rare species, or were readily explained by changes in mouth condition and water chemistry. We also confirmed a substantial range extension of the tropical crab, Varuna litterata, rediscovered the locally endemic amphipod, Quadrivisio aviceps, and reported several new distribution records. Gastropods had virtually disappeared from the system, whereas the previously unreported bivalve, Brachidontes virgilae, had become abundant. Overall, fish diversity dropped from 19 to 11 species, but this can largely be ascribed to differences in sampling frequency, season and mouth state. Comparisons of samples from like months showed the fish assemblage to have remained fairly stable, despite changes in inflowing water chemistry and infection of fish by the pathogenic water mould, Aphanomyces invadans. Bird abundance and diversity increased substantially. No alien invertebrate or fish species were recorded. Accordingly, in marked contrast to other smaller estuaries in the region, the Palmiet Estuary has remains in relatively good condition.Keywords: acidification, alien species, estuary condition, fish, invertebrates, Palmiet Estuary, species richness, physico-chemical characteristics

This study compares the composition, species richness and biomass of macrofaunal and algal assemblages on intertidal boulder shores as compared with those on adjacent rock-platforms, at six sites along the southwest coast of South Africa. Of 214 species identified, 175 were recorded on boulder shores and 124 on rock-platform shores; of these, 99 species were common to both habitat types, 92 were exclusive to boulders, and 23 were exclusive to rock-platforms. Significant differences in community structure (F(1,95) = 13.02, p < 0.01) (PERMANOVA test), species richness (F(1,95) = 14.28, p < 0.01), biomass (F(1,95) = 9.45, p < 0.01) and diversity (F(1,95) = 578.83, p < 0.01) (two-way ANOVA) were detected between the two habitat types. Average dissimilarity of community structure between rock-platform and boulder shores was 87.96% (SIMPER analysis). The increased species richness and biomass on boulder shores extended across all tidal levels, but was most marked in the highshore. These results confirm that boulder shores along the southwestern Cape support a distinct biota, richer and very different from that on adjacent rock-platforms, and rich in boulder-dependent species. We propose that boulder shores merit separate management and conservation targets as compared to rock-platforms, though the ecology of boulder shores in the region remains very poorly known and requires further study.Keywords: biodiversity, biomass, community structure, conservation, intertidal zone, rocky shores, species richness

The composition and seasonal variability of a False Bay suprabenthic reef-fish assemblage was investigated monthly at a protected reef site (to a depth of 25 m) for 14 months. In total, 25 484 fish from 28 species (26 demersal) were counted. Sparids dominated the assemblage (50 %of species and 87.3 %of individuals), followed by cheilodactylids (15.4 %of species and 7.5 %of individuals). Pachymetopon blochii (30.6 %), Sarpa salpa (17.7 %), Boopsoidea inornata (16.1 %), Chrysoblephus laticeps (10.4 %) and Spondyliosoma emarginatum (9.2 %) were the five most abundant species, while the ten most abundant species made up over 93 % of censused individuals. Composition was relatively stable year round, irrespective of water temperature variations, with 16 of the 26 reef-fish species censused encountered during more than 10 monthly censuses. Triakus megalopterus and large Chrysoblephus gibbiceps were the only species whose abundance appeared to vary seasonally.Key words: census, fish density.

In 1992 the invasive mussel Mytilus galloprovincialis began establishing beds on the centre sandbanks of Langebaan Lagoon. This global invader had previously been restricted to rocky shores along the South African coastline. In order to investigate the effect of the invasion on naturally-occurring communities, a comparative study between invaded areas and areas clear of invasion was conducted. Communities in these areas differed significantly (ANOSIM, R = 0.685, P < 0.01). The biomass supported in invaded areas (53 262 g/m2), was significantly greater than that in clear areas (1133 g/m2), (Mann-Whitney, U = 225, P < 0.001). Invertebrate densities supported in invaded (6780.1 individuals/m2) and clear areas (835 individuals/m2) were also significantly different, (Mann-Whitney, U = 219, P < 0.001). Of the 66 species recorded, only 33 % occurred in both clear and invaded areas (often in very different densities), 41 % occurred exclusively in invaded areas, and 26 % were restricted to non-invaded areas. These figures indicate a replacement of the naturally-occurring sandbank communities by those more typical of rocky shores. It is thus recommended that the invasive mussel beds be removed to conserve the natural biota of the centre banks, which lie within a national park.Key words: Bivalvia, alien invasive species, community effects.

Patterns of egg deposition and rates of egg development were examined for two endemic South African scyliorhinid shark species: Poroderma pantherinum, the leopard catshark, and Haploblepharus pictus, the dark shy shark. P. pantherinum laid their eggs at an average depth of 18.95 m (min: 7.4 m; max: : 26.8 m) preferentially attaching their eggs singly onto sea fans Leptogorgia palma, Eunicella papillosa and Eunicella tricoronata. H. pictus laid their eggs at an average depth 3m(min: 1m; max: 30.7 m) and attached their eggs, predominantly in pairs, to the seaweed Bifurcariopis capensis. The average temperature at which eggs were found were similar (15°C) and eggs were laid year-round. Embryo development was observed in the laboratory under constant controlled environmental conditions of 14 and 17°C. Embryo length–age relationships were linear for both species and there were significant differences in growth rate at the two temperatures. For P. pantherinum average growth rate was 0.37 mm/day at 14°C and 0.79 mm/day at 17°C. The average incubation period was 266 days at 14°C and 125 days at 17°C. Embryos thus grew two times faster and development time was 53% shorter when the temperature was raised by only 3°C. For H. pictus, the average growth rate was 0.49 mm/day at 14°C and 0.78 mm/day at 17°C. The incubation period was 242 days at 14°C and 190 days at 17°C. The embryos thus grew 1.6 times faster and incubation time was 21.5% shorter when temperature was raised by only 3°C.Key words: elasmobranchs, reproduction, egg laying, egg development, South Africa.

A sea anemone new to the South African fauna is reported from Table Bay Harbour and is identified as Metridium senile. The population was probably introduced from Europe and although well established, appears to be restricted to the harbour area.

In the first quantitative survey of intertidal fish from the South African west coast 62 intertidal rock pools were sampled at two sites, using the ichthyocide rotenone. A total of 2 022 fish representing 14 species belonging to only two families — the Clinidae (88–98% by number) and the Gobiesocidae (12–2%) — were caught. Clinus superciliosus, C. heterodon and the gobiesocid Chorisochismus dentex were the most abundant species in terms of both numbers and biomass. Vertical zonation of individual species on the shore indicated little separation of the habitat between species, although some species exhibited size-specific partitioning of the shore. Relationships between fish distribution and abundance and rock pool characteristics were elucidated by means of stepwise multiple regression, both at the whole community and individual species levels. The abundances of individual species were best predicted by pool size, although some species also showed an association with weed cover. For the community as a whole, the number of species present, the total number of fish and the total biomass in any pool were all dependent on pool size, height above LWS and amount of available cover. Relative to other South African sites the west coast has a low diversity of intertidal fish, combined with a high degree of dominance and a low level of habitat separation.

Book Review 1Book Title: Mammals of Malawi An annotated check list and atlasBook Authors: W.F.H. Ansell & R.J. DowsettThe Trendine Press, Zennor, St Ives, Cornwall, 1988. 170 pages text plus 53 pages of maps.Book Review 2Book Title: Frugivores and seed dispersalBook Authors: Alejandro Estrada & Theodore H. Fleming (Editors)Dr W. Junk Publishers, Dordrecht 1986. 392 pp.Book Review 3Book Title: Seasonal Adaptations of Insects (1986)Book Authors: Maurice J. Tauber, Catherine A. Tauber & Sinzo MasakiOxford University Press. 411 pages.Book Review 4Book Title: Biology of CopepodsBook Authors: Edited by G.A. Boxshall & H.K. SchminkeDevelopments in Hydrobiology 47. Kluwer Academic Publishers, 1988.Book Review 5Book Title: Stimulus-Secretion Coupling in Neuroendocrine SystemsBook Authors: Edited by D. Ganten, D. Pfaff & B. PickeringCurrent Topics in Neuroendocrinology Vol. 9. Springer-Verlag, 1988. 256 pp.Book Review 6Book Title: How Brain-like is the Spinal Cord?Book Author: Uwe WindhorstSpringer-Verlag, Berlin, 1988. 334 pp.Book Review 7Book Title: Complex Interactions in Lake CommunitiesBook Author: Edited by S.R. CarpenterSpringer-Verlag, New York 1988. 283 pp.Book Review 8Book Title: Cell movement and cell behaviourBook Author: J.M. LackieAllen & Unwin, London. 316 pp.Book Review 9Book Title: The Amphibians and Reptiles of BotswanaBook Author: Ronald D. AuerbachMokwepa Consultants (privately printed) 1987. (Obtainable from the Botswana Book Centre, P.O. Box 91, Gaborone, Botswana) 295 pages, 19 colour plates with 132 pictures, numerous figures and maps.

Gut content analysis shows the hottentot to be an omnivore, consuming a wide variety of algae and invertebrate prey. Amphipod crustaceans and rtiodophytes are the dominant food items, although hydroids, echinoderms and molluscs are also eaten in smaller quantities. Geographic variation in the diet was negligible, although seasonal trends were marked. A progressive change in diet occurs with fish size, larger individuals consuming progressively more algae. The hottentot diet differs from those of a number of co-occuring sparids in being far more generalized. Hottentot feed throughout the diel cycle, although feeding activity is markedly higher during the rising tide. The feeding cycle is further modified by a tendency to select particular food items at night. Available mathematical feeding rate simulation models for continuously feeding fish were improved to incorporate an asymptotic consumption rate. The resultant model was used to calculate daily consumption rates for hottentot, giving a value of 2,5% body weight per day. This is compared with values calculated using earlier models, and with published feeding rate values for other species.

No Abstract.

At 18 ·C the eggs of the kelp-fly, Fucellia capensis, hatch in 24 - 32 h and the larval and pupal stages last 10- 12 and 9-14 days respectively_ The growth curve is discontinuous, with declining relative growth rates in successive larval instars_ Food consumption is relatively independent of size, at 0,25 mg dry kelp mg -1 wet larva day -1_ Respiration rate is related to larval mass by the equation: Respiration rate µl O2 h -1) = 2,75 (wet mass larva)0.66. In terms of energy an individual larva consumes 245,5 J over its lifespan, grows to the equivalent of 43,9 J and respires 51,6 J, indicating an assimilation efficiency of 30% and a gross growth efficiency of 17%. Kelp-fly larvae are probably less significant consumers of drift kelp than amphipods or isopods, but they promote the decay of wrack beds and are favoured as food by sea-shore birds.

The fauna and flora of the canopy of a kelp bed off Oudekraal, on the Cape Peninsula, Is surveyed. Four species of epiphytic algae occur In the kelp canopy, three restricted to Ecklonia maxima and the fourth to Laminaria pallida. Epiphyte biomass is equivalent to 4-9% of host standing crop amongst E. maxima, but less than 1% in stands of L. pallida. Wherever E. maxima is common, epiphyte standing crop considerably exceeds that of benthic understorey algae. The canopy fauna comprises at least 27 species and is composed largely of small Crustacea, molluscs and polychaetes. Since these organisms are mainly associated with the epiphytic algae they are most abundant amongst E. maxima in the shallower regions of the kelp bed. In such areas the biomass of the canopy fauna may exceed that of the relatively impoverished benthos, but further offshore the canopy fauna is insignificant in relation to a rich benthic community. Indications are that canopy organisms are an important source of food for the fish of the kelp bed system.

Confusion between terms and ambiguities among definitions have long plagued the field of invasion biology. One result is disruption in flow of information from researchers to policy-makers and managers who rely on science to inform regulatory frameworks and management actions. We reviewed the South African marine biology literature to quantify the current usage of terminology describing marine invasions and found a variety of terms in use, few of which are defined when used. In response, we propose standard terminology that aligns with international practice. We then interpreted the Blackburn unified framework for biological invasions within the marine context and used this as a transparent way to apply the standardised terms to an updated list of marine alien species for the country. This resulted in the recognition of 36 alien and 53 invasive species within South Africa. Most notably, follow-up research is required to confirm the status of at least 11 listed species, the majority of which have been recorded only once, or not in the past 25 years. It is hoped that by standardising terminology, marine science in South Africa will better support authorities charged with managing the threat posed by marine alien species.Keywords: definitions, invasive species, state of knowledge

Mead, A., Carlton, J.T., Griffiths, C.L., Rius, M. (2011): Introduced and cryptogenic marine and estuarine species of South Africa. Journal of Natural History 45 (39-40): 2463-2524, DOI: 10.1080/00222933.2011.595836, URL: http://dx.doi.org/10.1080/00222933.2011.595836