Redescription of the hagfishes (Myxinidae: Eptatretus) from southern Africa

The hagfishes of the genus Eptatretus (Myxinidae) from southern Africa are known from three poorly studied species: Eptatretus hexatrema, a common species from Namibia and South Africa; Eptatretus profundus, known only from the holotype collected off Cape Point (South Africa); and Eptatretus octatrema, known from two syntypes from the Agulhas Bank (South Africa). Taxonomic, morphological and distributional information about these three species are reviewed and updated based on the examination of additional specimens collected in South African waters. Eptatretus hexatrema differs from all congeners by having six pairs (rarely seven) of gill apertures arranged in a straight line, 3/2 multicusp pattern of teeth, total cusps 44–49, trunk pores 53–60, total pores 93–107, preventral length 45.1–57.4% TL, tail length 11.6–14.3% TL, tail depth 5.7–8.1% TL, and two bilaterally symmetrical nasal-sinus papillae. Eptatretus octatrema differs from all congeners by having usually eight (some specimens with seven) pairs of gill apertures arranged in a straight line, 3/2 multicusp pattern of teeth, 42–46 total cusps, 22–26 prebranchial pores, 63–68 trunk pores, 104–117 total pores, and two bilaterally symmetrical nasal-sinus papillae. Eptatretus profundus differs from all congeners by having five pairs of gill apertures arranged in a straight line, 3/2 multicusp pattern of teeth, total cusps 42–46, prebranchial pores 12–15, branchial pores 4–5, trunk pores 48–52, tail pores 15–17, total pores 81–86, and body depth at PCD 7.0–9.7% TL. An identification key for the hagfishes from southern Africa is provided and the conservation status of E. octatrema, a species considered to be Critically Endangered, is discussed in light of the new findings.     

4. BIRD PROTECTION POLICIES AND LAWS

Walter, C. B., Cooper, J. &; Suter, W. 1987. Diet of Swift Tern chicks in the Saldanha Bay region, South Africa. Ostrich 58:49-53.

The diet of the Swift Tern Sterna bergii was investigated over a ten-year period off the west coast of South Africa by collecting regurgitations from chicks during ringing operations. A total of 1311 prey items of 25 identifiable species (20 of which were fish) was collected. Fish formed 86% of all the prey items. Other prey species included cephalopods, crustaceans and insects. 60% by number of prey taken consisted of pelagic shoaling fish, of which Cape Anchovy Engraulis japonicus occurred most frequently and was the most abundant prey species in seven of the nine years in which samples were collected. Weekly collections in 1984 confirmed that pelagic shoaling fish, in particular Cape Anchovy, were the most abundant prey taken during the chick-rearing period. Prey size varied from 7 to 138 mm in length and from 0,l to 30,0 g in mass.     

A new species of Schoutedenichia Jadin & Vercammen-Grandjean, 1954 from Madagascar and a re-description of S. dutoiti (Radford, 1948) from South Africa (Acariformes: Trombiculidae)

A new chigger mite species, Schoutedenichia microcebi n. sp. is described from the grey mouse lemur Microcebus murinus (J.F. Miller) from Madagascar. The new species is closely related to S. dutoiti (Radford, 1948), a species described from a single specimen collected on a rodent in South Africa. Examination of the holotype and new material on S. dutoiti from South Africa enabled us to re-describe this species and provide new data on its hosts and geographical distribution.

     

In situ observations on benthic siphonophores (Physonectae: Rhodaliidae) and descriptions of three new species from Indonesia and South Africa

Three new species of siphonophores (Rhodaliidae), a little known, uniquely benthic, family of Physonectae (Hydrozoa, Cnidaria), are described from specimens observed and collected at depths between 120 and 360 m off Indonesia and South Africa by the submersible JAGO. Special reference is made to in situ observations and video close‐ups that revealed detailed information on locomotory, fishing and feeding behaviour.     

Refuges and risks: Evaluating the benefits of an expanded MPA network for mobile apex predators

Aim

Concurrently, assessing the effectiveness of marine protected areas and evaluating the degree of risk from humans to key species provide valuable information that can be integrated into conservation management planning. Tiger sharks (Galeocerdo cuvier) are a wide‐ranging ecologically important species subject to various threats. The aim of this study was to identify “hotspots” of tiger shark habitat use in relation to protected areas and potential risks from fishing.

Location

Southwest Indian Ocean, east coast of South Africa and Mozambique.

Methods

Satellite tags were fitted to 26 tiger sharks. A subset of 19 sharks with an average period at liberty of 197 (SD = 110) days were analysed using hotspot analysis to identify areas of core habitat use. The spatial and temporal overlap of significant hotspots with current and planned marine protected areas as well as risks from fishing and culling was then calculated.

Results

There was a 5.97% spatial overlap between tiger shark hotspots and marine protected areas, which would increase significantly (p < .05) to 24.36% with the expansion of planned protected areas in South Africa and could be as high as 41.43% if Mozambique similarly expanded neighbouring protected area boundaries. Tiger sharks remained largely coastal, but only showed a spatial overlap of 5.12% with shark culling nets in South Africa. Only three sharks undertook open ocean migrations during which they were more likely to interact with longline fisheries in the region.

Main conclusions

This study demonstrates how spatial information can be used to assess the overlap between marine protected areas and the core habitats of top marine predators and highlights how congruent transnational conservation management can improve the effectiveness of protected areas. Core habitat use of marine apex predators may also be indicative of productive habitats, and therefore, predators such as tiger sharks could act as surrogate species for identifying key habitats to prioritize for conservation planning.

     

SOME NOTES ON BIRDS OF SOUTHERN RHODESIA

Cyrus, Digby P. 1986. Seasonal and spatial distribution of Redheaded Quelea (Quelea erythrops) in South Africa. Ostrich. 57: 162–169.

There are 48 records of Redheaded Quelea Quelea erythrops occurring in South Africa. Most are for the summer and early autumn months from October to April and all are restricted to the low lying eastern coastal areas. The pattern of occurrence in South Africa is similar to that in adjoining countries to the north; the species does not however occur as regularly in the south. Breeding or attempted breeding has been recorded on six occasions. This shows the typical pattern of occurrence of a species at the southern limit of its distribution.

There is some evidence to suggest that its occurrence may be associated with “wet” years when rainfall is above average. The Redheaded Quelea may be considered as a rare and irruptive summer vagrant to South Africa, which only breeds when conditions are suitable.     

Phylogenetic placement and population structure of Indo‐Pacific bottlenose dolphins (Tursiops aduncus) off Zanzibar,Tanzania, based on mtDNA sequences

Phylogenetic placement of bottlenose dolphins from Zanzibar, East Africa and putative population differentiation between animals found off southern and northern Zanzibar were examined using variation in mtDNA control region sequences. Samples (n= 45) from animals bycaught in fishing gear and skin biopsies collected during boat surveys were compared to published sequences (n= 173) of Indo‐Pacific bottlenose dolphin, Tursiops aduncus, from southeast Australian waters, Chinese/Indonesian waters, and South African waters (which recently was proposed as a new species) and to published sequences of common bottlenose dolphin, Tursiops truncatus. Bayesian and maximum parsimony analyses indicated a close relationship between Zanzibar and South African haplotypes, which are differentiated from both Chinese/Indonesian and Australian T. aduncus haplotypes. Our results suggest that the dolphins found off Zanzibar should be classified as T. aduncus alongside the South African animals. Further, analyses of genetic differentiation showed significant separation between the T. aduncus found off northern and southern Zanzibar despite the relatively short distance (approximately 80 km) between these areas. Much less differentiation was found between southern Zanzibar and South Africa, suggesting a more recent common evolutionary history for these populations than for the northern and southern Zanzibar populations.     

Structure and Dynamics of the Shark Assemblage off Recife,Northeastern Brazil

Understanding the ecological factors that regulate elasmobranch abundance in nearshore waters is essential to effectively manage coastal ecosystems and promote conservation. However, little is known about elasmobranch populations in the western South Atlantic Ocean. An 8-year, standardized longline and drumline survey conducted in nearshore waters off Recife, northeastern Brazil, allowed us to describe the shark assemblage and to monitor abundance dynamics using zero-inflated generalized additive models. This region is mostly used by several carcharhinids and one ginglymostomid, but sphyrnids are also present. Blacknose sharks, Carcharhinus acronotus, were mostly mature individuals and declined in abundance throughout the survey, contrasting with nurse sharks, Ginglymostoma cirratum, which proliferated possibly due to this species being prohibited from all harvest since 2004 in this region. Tiger sharks, Galeocerdo cuvier, were mostly juveniles smaller than 200 cm and seem to use nearshore waters off Recife between January and September. No long-term trend in tiger shark abundance was discernible. Spatial distribution was similar in true coastal species (i.e. blacknose and nurse sharks) whereas tiger sharks were most abundant at the middle continental shelf. The sea surface temperature, tidal amplitude, wind direction, water turbidity, and pluviosity were all selected to predict shark abundance off Recife. Interspecific variability in abundance dynamics across spatiotemporal and environmental gradients suggest that the ecological processes regulating shark abundance are generally independent between species, which could add complexity to multi-species fisheries management frameworks. Yet, further research is warranted to ascertain trends at population levels in the South Atlantic Ocean.     

Species diversity and distribution of lepidopteran stem borers in South Africa and Mozambique

Country‐wide surveys of lepidopteran stem borers in wild host plants were undertaken between 2006 and 2009 in South Africa and 2005 and 2010 in Mozambique. A total of 4438 larvae were collected from 65 wild host plants in South Africa and 1920 larvae from 30 wild host plants in Mozambique. In South Africa and Mozambique, 50 and 39 stem borer species were recovered, respectively, with four new species and two new genera among noctuids. Less than 5% of the total number of species collected are considered to be economically important in Africa. These species were Busseola fusca (Fuller) (Noctuidae), Chilo partellus (Swinhoe) (Crambidae) and Sesamia calamistis Hampson (Noctuidae). Data from this study and others in East Africa on the very low abundance of stem borers in wild host plants question the putative role of wild host plants as reservoir for stem borer pests. One new host plant family (Prioniaceae), as well as 24 and 13 wild hosts from South Africa and Mozambique respectively, was added to the list of known hosts in Africa.     

Ecological redundancy between coral reef sharks and predatory teleosts

Reef sharks may be ecologically redundant, such that other mesopredatory fishes compensate for their functions when they decline in number, preventing trophic cascades. Oral jaw gape, hereafter referred to as gape, determines maximum prey size in many piscivores and therefore affects the size structure of prey assemblages. Here, we examine whether gape and maximum prey size differ between five species of reef shark and 21 species of teleost (n?=?754) using data collected from 38 reefs in the Indo-Pacific. Sharks displayed relatively small gape dimensions compared to most teleost species and, at smaller sizes, the giant trevally Caranx ignobilis and other teleosts may be able to consume larger prey than similar-sized sharks. However, ecological redundancy between reef sharks and teleosts appears to decline at larger sizes, such that the grey reef shark Carcharhinus amblyrhynchos, for example, may be capable of consuming larger prey than any other reef predator at its largest sizes, regardless of prey body shape. Moreover, sharks may be able to consume proportionally larger prey as they grow, in contrast to reef teleosts, which may largely be limited by their gapes to ever-smaller prey as a proportion of their body size. Our results also suggest that reef sharks may be unable to swallow whole prey that are >?36% of their length, consistent with gut-content studies. Conservation of reef ecological function may therefore depend not only on the protection of sharks but also particular size classes and key components of the mesopredatory guild.

     

Southern African skate biodiversity and distribution

The skates (Family Rajidae) have 12 genera and possibly 28 species off southern Africa (southern Angola, Namibia, South Africa and Mozambique). The geographic and bathymetric distribution and the taxonomic composition of the southern African skate fauna are analysed and the distribution mapped. The southern African skate fauna is best known off the temperate west coast of South Africa from the intertidal to approximately 1,200 meters, but poorly known below 1,200 m and sketchily known in warm-temperate and tropical parts of the area. Southern African skates of the temperate continental shelves above 100 m are not diverse and regularly include one species of the genus Dipturus, one species of Leucoraja, two species of Raja (including R. straeleni, the most abundant skate in southern African waters) and the giant skate Rostroraja alba. All of these skates are ‘shelf overlap’ species that range onto the outer shelves and uppermost slopes, and none are confined to inshore environments. Skate diversity increases on the outer shelves and upper slopes. At least half of the skate species are endemic to the southern African region; other species also occur off East or West Africa, a few extend to European waters, and records of one species, Amblyraja taaf, appear to be of strays from nearby sub-Antarctic seas. The genus Bathyraja and softnose skate group (Arhynchobatinae) are surprisingly limited (a single species) in deep-water off southern Africa (unlike other regions including the Antarctic), and almost all of southern African skates are members of the Rajinae. Amongst rajines, the tribes Amblyrajini (Amblyraja, two species, Leucoraja, two species, and Rajella, five species) Rajini (Dipturus, six species, Okamejei, one species, Raja, two species, and Rostroraja, one species), and Anacanthobatini (Anacanthobatis, two species, and Cruriraja, three species) predominate, while Gurgesiellini has a species of Neoraja and possibly two of Malacoraja.     

New monogeneans from the bathydemersal southern African endemic catshark,Holohalaelurus regani (Gilchrist, 1922)

The catshark genus Holohalaelurus Fowler is currently represented by five species distributed off the southern and eastern parts of the African coast. Very few parasitological records exist for any of these five species, representing a significant knowledge gap. We report the first monogenean species from the bathydemersal species Holohalaelurus regani (Gilchrist): a new species of Microbothriidae Price, 1936, Leptomicrobothrium holohalaelure n. sp. from the dorsal skin surface, and a new species of Hexabothriidae Price, 1942 representing a new genus, Scyliorhinocotyle narvaezae n. gen., n. sp., from the gill lamellae. Both monogenean records represent the first for any member of the catshark genus Holohalaelurus. Previously we focused on the identification of monogenean taxa of emerging veterinary importance for public aquaria. We now begin a focused effort to document a generally unexplored monogenean biodiversity from diverse marine habitats off South Africa.

     

NEW ARRENURUS SPECIES (ACARI,HYDRACHNELLAE, ARRENURIDAE) FROM SOUTHERN AFRICA

SUMMARY

Five new Arrenurus spp, from Southern Africa are described: A. amoenus sp. nov. from Natal, A. agnewi sp. nov., A. curtipalpus sp. nov., A. pedatus sp. nov. and A. cavatus sp. nov. from Botswana. The species from Natal came from an older collection belonging to the National Institute for Water Research. The species from Botswana were collected recently by Dr J.D. Agnew¹

The water mite fauna of South Africa is only partly known. Therefore it is important that collectors should know that alcohol and formalin are not suitable fixatives. Fixing and storing is most successful in the following mixture: 5 parts glycerin, 2 parts glacial acetic acid and 3 parts water.     

Geographical and temporal variation in the diet of Bank Cormorants Phalacrocorax neglectus in South Africa

The Bank Cormorant Phalacrocorax neglectus is endemic to the Benguela upwelling ecosystem off southwest Africa and is classified as Endangered owing to a recent large reduction in its number. It is thought that food scarcity, including a decreased abundance of West Coast rock lobster Jasus lalandii, has been a major driver of the decrease, yet its diet in South Africa is poorly known. We collected 941 pellets regurgitated by Bank Cormorants, at 18 South African breeding colonies during 1975–1985, and 1 523 pellets at 17 colonies during 1995–2002. The species composition of the diet (% numbers) was significantly different between the two periods, with widespread decreases in proportions of rock lobster in the west and of octopus and cuttlefish Sepia spp. at most localities. These taxa were replaced in the diet by fish, including Gobiidae and Clinidae. The pelagic goby Sufflogobius bibarbatus, an important prey of Bank Cormorants in Namibia, was absent from pellets collected in 1975–1985 but common at northern localities from 1995–2002. Composition of the diet by frequency of occurrence was only determined for 1995–2002, when rock lobster was present in 67% of all samples collected, cuttlefish in 39%, and Clinidae in 32%. Data for 1975–1985 and 1995–2002 showed that carapace lengths of rock lobsters eaten by Bank Cormorants averaged 56 mm (range 22–82 mm) and 50 mm (range 22–75 mm), respectively, which compares to the minimum legal size of 75 mm for fisheries in South Africa. This energy- rich prey item was an important constituent of the diet in the winter breeding period.     

Cladistic analysis of the morphological characters of Pseudocharopinus Kabata, 1964 and keys to the species of Pseudocharopinus and Charopinus Krøyer, 1863 based on the morphology of adult females

Kabata separated species of Pseudocharopinus Kabata, 1964 and Charopinus Krøyer, 1863 in 1964 based mainly on four characteristics. Currently Pseudocharopinus has 11 species while Charopinus consists of three species considered valid. Pseudocharopinus malleus (Rudolphi in Nordmann, 1832) and Charopinus dubius T. Scott, 1900 were collected and studied from hosts off South Africa. Additional to previous reports from South African waters, P. malleus is reported from Torpedo sinuspersici Olfers and T. fuscomaculata Peters while C. dubius is reported from Leucoraja wallacei (Hulley) and Rajella dissimilis (Hulley), all new host records. In an attempt to estimate the evolutionary relationships among Pseudocharopinus spp. a cladistic analysis was performed by means of parsimony using described and illustrated features of the adult females. Due to the mostly unresolved 50% majority rule tree, a key for the identification of the adult females of Pseudocharopinus spp. is compiled. Additionally, a key for the identification of adult females of Charopinus spp. is provided.

     

Record of Blue tilapia Oreochromis aureus (Steindachner, 1864) in the Eerste River catchment,Western Cape province,South Africa

Oreochromis aureus was imported from Israel into South Africa in 1959 but data on its current status in South Africa are lacking. Genomic DNA was extracted and the COI gene amplified at the South African Institute for Aquatic Biodiversity. The identity of the sequences and specimens was determined using the Barcode of Life Data Systems and GenBank. Morphological and genetic assessment demonstrated that 11 specimens collected from two farm dams in the Eerste River System, Western Cape province, were Oreochromis aureus. A MaxEnt model compiled using global distribution, rainfall and temperature data predicted that large areas of southern Africa were climatically suitable for this species, indicating considerable invasion debt in southern Africa. As a result, surveys to assess for the extent of the invasion in South Africa and eradication of existing populations, if feasible, are recommended management actions.     

1. PELICANS BREEDING ON SEAL ISLAND

Clark, A. 1974. The status of the whistling ducks in South Africa. Ostrich 45:1-4. Since the 1920's the status of Dendrocygna viduata and D. bicolor has changed from that of an irregular to that of a regular species in the Transvaal, Zululand, Natal and Orange Free State. In more recent years their numbers have shown a steady increase and breeding has been established. D. viduata numbers built up more quickly than D. bicolor and it has become an established resident whereas D. bicolor is primarily a summer visitor.

In the Western Cape Province there has been little change in the status of either species but there are indications that D. viduata is appearing mote regularly in the Eastern Cape Province. The position in East Griqualand and the Transkei is obscure. In South West Africa, excluding the north east corner, D. viduata remains irregular and D. bicolor rare.

The preference shown by both species for areas where sewage effluent is disposed of and for new storage dams inevitably links their spread and increase with that of the human population.