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Geno-Phenotypic Regression and Juvenile-Mature Correlations: Methodological Tools for Clonal Selection of Eucalyptus Hybrids in Congo
Item type: Journal Article • Journal: South African Forestry Journal • Authors: Jean-Marc Bouvet --- Centre Technique Forestier Tropical Department of the CIRAD, FranceThis paper discusses different ways to improve clonal selection and clonal variety propagation for the industrial plantations in Congo. -
The Genetic Control of Ring Width, Wood Density and Tracheid Length in the Juvenile Core of Pinus patula
Item type: Journal Article • Journal: South African Forestry Journal • Authors: R.D. Barnes --- Forest Research Centre, Zimbabwe J.S. Birks --- , United Kingdom G. Battle --- Forest Research Centre, Zimbabwe L.J. Mullin --- Forest Research Centre, ZimbabweControlled crosses were made between six Pinus patula Schiede & Deppe plus trees selected in plantations. Six full-sib families and two commercial checks were planted in randomised complete block thrice-replicated progeny tests at two sites in Zimbabwe. At 7,5 years,... -
Basic Density, Tracheid Length and Strength Properties of Juvenile and Mature Wood of Pinus patula Grown in Tanzania
Item type: Journal Article • Journal: South African Forestry Journal • Authors: R.C. Ishengoma --- Department of Wood Utilization, Faculty of Forestry, P.R. Gillah --- Department of Wood Utilization, Faculty of Forestry, S. Iddi --- Department of Wood Utilization, Faculty of Forestry,More than 70% of Tanzanian plantations consist of conifers, 60% of which are Pinus patula plantations. Juvenile wood is one of the most important sources of variability. -
THE JUVENILE FISH POPULATION IN THE MARGINAL AREAS OF THE HENDRIK VERWOERD DAM
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.A. Cambray --- Cape Department of Nature and Environmental Conservation, South Africa S. Hahndiek --- Cape Department of Nature and Environmental Conservation, South Africa Q. Hahndiek --- Cape Department of Nature and Environmental Conservation, South AfricaSmall seine nets were used to collect minnow and juvenile fish from a variety of habitats around the 350 km shoreline of the Hendrik Verwoerd Darn. In addition several areas were sectioned off from the darn and poisoned. The species... -
DUNE MINING AND THE NHLABANE SYSTEM: CAN BIODIVERSITY AND THE NURSERY FUNCTION BE MAINTAINED?
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: D. P. Cyrus --- , , South Africa V. Wepener --- , , South AfricaA four year study of the Nhlabane Estuary and Lake System was undertaken over the period 1992 to 1995. Data gathered clearly showed that in terms of ichthyofauna, the estuary plays an important role as a nursery ground for juveniles... -
Juvenile fish recruitment through wave-overtopping into a closed subtropical estuary
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: L Vivier DP CyrusThe fish fauna of the subtropical Nhlabane estuary in northern KwaZulu-Natal was studied during a regional drought over the period 1991–1995. The estuary mouth closed in late 1991, due to the drought and to water abstraction from the system, and... -
The food and feeding habits of five freshwater and brackish-water fish species in Nigeria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PO Ajah MN Georgewill MO AjahThe food and feeding habits of five economically important fresh-and brackish-water fishes, Channa obscura, Chrysichthys nigrodigitatus, Heterotis niloticus, Synodontis nigrita and Trachinotus maxillosus, were investigated. A number of techniques were used to carry out gut content analysis, including the Hynes... -
Population Dynamics and Spawning of the Flatfish Solea Bleekeri and Pseudorhombus Arsius in the Intertidal Area of Inhaca Island, Moçambique
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A. M. P. Van Schie W. F. De BoerThe population dynamics of flatfish Solea bleekeri and Pseudorhombus arsius within the intertidal area of Inhaca Island, Moçambique, was investigated using bottom trawl data collected during summer (December 1996 – March 1997) and winter (June 1997 – August 1997). The... -
Settlement patterns, size and growth of puerulus and juvenile rock lobster Jasus lalandii at an oyster farm in Saldanha Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JC Groeneveld --- , South Africa CL Greengrass --- Marine Biology Research Institute, Department of Zoology, South Africa DL van Zyl --- Branch Fisheries, Department of Agriculture, Forestry and Fisheries, South Africa GM Branch --- Marine Biology Research Institute, Department of Zoology, South AfricaTrends in the abundance, size and growth of newly settled pueruli and early juveniles of the rock lobster Jasus lalandii were determined from samples obtained from mesh bags used for oyster mariculture in Saldanha Bay, South Africa. Totals of 3... -
Grade verification of SA pine — bending, modulus of rupture, modulus of elasticity, tension and compression
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: Walter Burdzik --- , AfricaThe last verification of SA pine timber strengths was done in the early 1980s. Uses of the pine logs and the rotation periods have changed. This investigation was undertaken to verify the visual grade 5 grading rules of SANS 1783-2... -
Corewood in South African pine: necessity and opportunities for improvement
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: FS Malan --- , South AfricaSouth Africa has made excellent progress in breeding plantation trees fulfilling the primary demands of improved volume growth, stem and branching characteristics, tolerance to pests and diseases, and general adaptability. This has had marked positive impacts on wood quality, as... -
Clonal differences in log end splitting in Eucalyptus grandis in relation to age, parent performance, growth rate and wood density in two even-aged trials in Mpumalanga, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: FS MalanThis paper discusses the juvenile–mature correlation of log end splitting among Eucalyptus grandis clones from two trials and how differences in splitting relate to differences in wood density, pith-to-bark gradient and growth rate. Two approximately 20-year-old Eucalyptus grandis clonal trials... -
Edgy Edgars: The Restless Youth in Suzanna Nelson's Nightmare along the River Nile: A Story of Twentieth Century Slavery
Item type: Journal Article • Journal: Eastern African Literary and Cultural Studies • Authors: Paul M. Mukundi --- Department of Literature, KenyaSuzanna E. Nelson's first novel, Nightmare along the River Nile: A Story of Twentieth Century Slavery shows the danger faced by youth during war. While the young adult stage of life is generally characterized by unsteadiness—social, professional and otherwise—because individuals... -
Spatial and seasonal patterns in sighting rate and life-history composition of the white shark Carcharodon carcharias at Mossel Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Ryklief --- Department of Zoology, South Africa PA Pistorius --- Department of Zoology, South Africa R Johnson --- Oceans Research, South AfricaWhite sharks Carcharodon carcharias aggregate at specific times of the year at localities along the South African coast. At Mossel Bay, on the southern Cape coast, four sites were sampled (Seal Island, Hartenbos, Kleinbrak and Grootbrak) to investigate spatial and... -
Preliminary examination of hatching season and growth of Engraulicypris sardella (Pisces: Cyprinidae) larvae and juveniles in Lake Malawi
Item type: Journal Article • Journal: African Zoology • Authors: Shinsuke Morioka --- Department of Aquaculture and Fisheries Science, Bunda College of Agriculture, Malawi Emmanuel Kaunda --- Department of Aquaculture and Fisheries Science, Bunda College of Agriculture, MalawiThe hatching period and the growth of Malawian cyprinid Engraulicypris sardella larvae and juveniles collected from two sites along the southwestern shoreline of Lake Malawi were investigated using otolith increment information. The lapillus was used to determine the age in... -
Residency and small-scale movement behaviour of three endemic sparid fishes in their shallow rocky subtidal nursery habitat, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Peter A. Watt-Pringle --- Department of Ichthyology and Fisheries Science, Rhodes University, South Africa Paul D. Cowley --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa Albrecht Götz --- Elwandle Node, South African Environmental Observation Network (SAEON), South AfricaThe residency and small-scale movements of early juveniles (<175 mm fork length) of three sparid fish species were examined in the shallow subtidal zone along a 500 m stretch of rocky coastline near Schoenmakerskop (Eastern Cape Province, South Africa). A... -
The variation of microfibril angle in South African grown Pinus patula and its influence on the stiffness of structural lumber
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: C Brand Wessels --- Department of Forest and Wood Science, South Africa Francois S Malan --- Postgraduate Forest Programme, South Africa Martin Kidd --- Centre for Statistical Consultation, South Africa Tim Rypstra --- Department of Forest and Wood Science, South AfricaReduction in the rotation ages of softwood saw-log plantations in South Africa is causing increased proportions of low stiffness sawn lumber at final harvest. It has been shown for some species that the microfibril angle (MFA) of the S2 layer... -
Management with fertility preservation of an ovarian juvenile granulosa cell tumour presenting with retroperitoneal spread and bilateral ureteric obstruction
Item type: Journal Article • Journal: Southern African Journal of Gynaecological Oncology • Authors: G C Du Toit --- Part-Time Consultant, Unit of Gynaecological Oncology, Tygerberg Hospital, University of Stellenbosch, -
Juvenile survival and population regulation in southern elephant seals at Marion Island
Item type: Journal Article • Journal: African Zoology • Authors: P.A. Pistorius --- Mammal Research Institute, South Africa M.N. Bester --- Mammal Research Institute, South AfricaWe examined annual juvenile survival in southern elephant seals (Mirounga leonina) at Marion Island for the period 1994–1999 during which time the population was stable. Using mark–recapture models, we tested for age- and sex-specific differences in survival rates over the... -
Spatio-temporal patterns of coral recruitment at Vamizi Island, Quirimbas Archipelago, Mozambique
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: E Sola --- School of Life Sciences, South Africa I Marques da Silva --- Faculdade de Ciências Naturais, Moçambique D Glassom --- School of Life Sciences, South AfricaSpatial and temporal patterns of recruitment of reef corals were assessed for the first time in Mozambique by deploying settlement plates at various spatio-temporal scales between October 2012 and October 2013. The abundance of juvenile corals (5−50 mm in diameter) was... -
Intertidal mangrove boundary zones as nursery grounds for the mud crab Scylla serrata
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: DO Mirera --- Kenya Marine and Fisheries Research Institute (KMFRI), KenyaThe demand for mud crab Scylla serrata (Forsskål 1775) in the global market has increased, hence there is growing momentum to farm the species in Africa. Aquaculture production in Kenya and elsewhere in East Africa currently relies on juvenile seeds... -
Comparison of physiological responses to high temperatures in juvenile and adult Cape Rockjumpers Chaetops frenatus
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Krista N Oswald --- Department of Zoology, South Africa Alan TK Lee --- Fitzpatrick Institute of African Ornithology, DST/NRF Centre of Excellence, South Africa Ben Smit --- Department of Zoology, South AfricaConcerns about climate change have led to an increase in studies on physiological mechanisms birds possess to cope with increasing temperatures. For range-restricted species such as Cape Rockjumpers Chaetops frenatus, whose population declines are correlated with habitat warming, we identified... -
Dispersal dynamics of juvenile Secretarybirds Sagittarius serpentarius in southern Africa
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Melissa A Whitecross --- Terrestrial Bird Conservation Programme, BirdLife South Africa, South Africa Ernst F Retief --- Important Bird and Biodiversity Areas Programme, BirdLife South Africa, South Africa Hanneline A Smit-Robinson --- Terrestrial Bird Conservation Programme, BirdLife South Africa, South AfricaKnowledge of the dispersal behaviour of southern Africa’s juvenile Secretarybirds Sagittarius serpentarius was previously limited to a small number of ring recoveries (n = 4) in South Africa. From 2012 to 2015, 10 GSM-GPS solar trackers were fitted to juvenile... -
Oxygen and temperature influence the distribution of deepwater Cape hake Merluccius paradoxus in the southern Benguela: a GAM analysis of a 10-year time-series
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: FL Mbatha --- Department of Biological Sciences and Marine Research Institute, South Africa D Yemane --- Department of Biological Sciences and Marine Research Institute, South Africa M Ostrowski --- Institute of Marine Research (IMR), Norway CL Moloney --- Department of Biological Sciences and Marine Research Institute, South Africa MR Lipiński --- Department of Ichthyology and Fisheries Science, South AfricaGeneralised additive models (GAMs) were applied to survey data to assess the influence of dissolved oxygen, water temperature and year of sampling upon the presence/absence of small (≤15 cm TL), medium (16–34 cm TL) and large (≥35 cm TL) size... -
Review of fish life history strategies associated with warm temperate South African estuaries and a call for effective integrated management
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NA Strydom --- Department of Zoology, South Africa Y Kisten --- Department of Zoology, South AfricaRefuge and feeding areas for young fish in estuaries are important for the survival of fish and replenishment of coastal fish stocks, particularly in the temperate south east coast of southern Africa. Larvae and juveniles of important fishery species recruit... -
Evaluating Kenya’s coastal gillnet fishery: trade-offs in recommended mesh-size regulations
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: K Osuka --- , Kenya JA Kawaka --- , Kenya MA Samoilys --- , KenyaGillnets are a widely used fishing gear in Kenya’s artisanal fisheries, yet their mesh sizes are inadequately monitored or regulated. This study evaluated the impacts of gillnets of seven stretched-mesh sizes, through comparative analysis of species-related metrics and catch per... -
Bull shark Carcharhinus leucas recruitment into the St Lucia Estuary, South Africa, after prolonged mouth closure, and the first observation of a neonate bull shark preyed on by a Nile crocodile Crocodylus niloticus
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: R Daly --- , South Africa P Le Noury --- , United Kingdom TN Hempson --- , Mozambique M Ziembicki --- , Mozambique JM Olbers --- , South Africa GM Brokensha --- , South Africa BQ Mann --- , South AfricaEstuaries provide critical nursery habitat for juvenile bull sharks Carcharhinus leucas, as they have the ability to withstand a wide range of salinities. St Lucia is the largest estuarine lake in Africa and was once a key nursery for bull... -
Tidal influence on fish faunal occurrence and distribution in an estuarine mangrove system in Ghana
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: NK Asare --- , Ghana JL Javier --- , United StatesThis study assessed the effects of tidal stages and habitat conditions on nekton assemblage and distribution in the Kakum River estuarine mangrove system in the Central Region of Ghana. Teleosts and crustaceans were sampled using pole seine and cast net... -
Yellow-billed Kite Milvus aegyptius nesting dynamics and breeding success across a human-modified landscape
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Roger N Porter --- , William W Howells --- , Ingrid B Weiersbye --- , South Africa Ben Hoffman --- University of KwaZulu-Natal, South Africa Sean N Porter --- Oceanographic Research Institute (ORI), South AfricaAnthropogenic habitat transformation is one of the leading causes of biodiversity decline. Migratory birds, particularly many raptor species, are increasingly threatened by global environmental change. We investigated the nesting dynamics and potential determinants of breeding success in a population of... -
Distribution and movement patterns of white musselcracker Sparodon durbanensis, a South African endemic seabream
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: BQ Mann --- Oceanographic Research Institute (ORI), South Africa GL Jordaan --- Oceanographic Research Institute (ORI), South Africa R Daly --- Oceanographic Research Institute (ORI), South Africa WN Dalton --- Oceanographic Research Institute (ORI), South Africa PA Watt-Pringle --- Oceanographic Research Institute (ORI), South Africa K Hewett --- Rhodes University, South Africa WM Potts --- Rhodes University, South AfricaThe white musselcracker Sparodon durbanensis (family Sparidae) is a highly prized shore angling and spearfishing species. This study investigated its movement behaviour along the southeastern seaboard of South Africa, using tag-recapture data. A total of 3 378 S. durbanensis were...