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You searched for: Journal name African journal of marine science Remove constraint Journal name: African journal of marine science Publication year rev 7989-2011 Remove constraint Publication year rev: 7989-2011 Source 2011 v.33 no.1 Remove constraint Source: 2011 v.33 no.1
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1. Changes in demersal fish assemblages on the west coast of South Africa, 1986–2009

Author:
LJ Atkinson; RW Leslie; JG Field; A Jarre
Source:
African journal of marine science 2011 v.33 no.1 pp. 157-170
ISSN:
1814-2338
Subject:
Jasus; coasts; demersal fish; ecosystems; geographical variation; latitude; lobsters; multivariate analysis; population dynamics; surveys; temporal variation; South Africa
Abstract:
... Research survey data collected over 24 years (1986–2009) were used to explore long-term changes in demersal fish assemblages on the west coast of South Africa. Differences in spatial (latitude and depth) and temporal (seasonal and annual) factors were examined using multivariate analyses. Fish assemblages are clearly influenced by depth, with a distinct change in the region of the shelf break betw ...
DOI:
10.2989/1814232X.2011.572378

2. Distribution and seasonality of cetaceans in tropical waters between Angola and the Gulf of Guinea

Author:
CR Weir
Source:
African journal of marine science 2011 v.33 no.1 pp. 1-15
ISSN:
1814-2338
Subject:
Agoseris; Megaptera novaeangliae; Physeter macrocephalus; Tursiops truncatus; data collection; geophysics; species diversity; spring; surveys; winter; Angola; Gulf of Guinea
Abstract:
... The species richness, spatial distribution, seasonality and interspecific associations of cetaceans in tropical oceanic waters between the Gulf of Guinea and Angola were examined using 5 905.3 h of dedicated survey effort collected from 13 platforms of opportunity (geophysical vessels) between 2004 and 2009, and from incidental records. Most effort (87.8%) was recorded in waters >1 000 m deep. A t ...
DOI:
10.2989/1814232X.2011.572333

3. Gear selectivity of large-mesh nets and drumlines used to catch sharks in the Queensland Shark Control Program

Author:
WD Sumpton; SM Taylor; NA Gribble; G McPherson; T Ham
Source:
African journal of marine science 2011 v.33 no.1 pp. 37-43
ISSN:
1814-2338
Subject:
Caretta caretta; Chelonia mydas; Galeocerdo cuvier; Sphyrnidae; bycatch; marine mammals; risk; sea turtles; sharks; ventilators; Queensland
Abstract:
... Catches of sharks and bycatch in large-mesh nets and baited drumlines used by the Queensland Shark Control Program were examined to determine the efficacy of both gear types and assess fishing strategies that minimise their impacts. There were few significant differences in the size of both sharks and bycatch in the two gear types, apart from significantly smaller (p < 0.05) tiger sharks Galeocerd ...
DOI:
10.2989/1814232X.2011.572335

4. Liver lipids of Indian and Atlantic Ocean spinner Carcharhinus brevipinna and blacktip Carcharhinus limbatus sharks

Author:
B Davidson; M Zayed; S Zayed; G Cliff
Source:
African journal of marine science 2011 v.33 no.1 pp. 115-118
ISSN:
1814-2338
Subject:
Carcharhinus limbatus; coasts; fatty liver; liver; oils; polyunsaturated fatty acids; sharks; Atlantic Ocean; Gulf of Mexico; Indian Ocean; South Africa
Abstract:
... Shark liver oils are rich in polyunsaturated fatty acids, especially the n3 moieties. Data on the liver fatty acids of sharks from African waters, however, are limited. Liver samples from sharks from the western Indian Ocean off the east coast of South Africa and those from the Atlantic Ocean and Gulf of Mexico were examined. This study reports on the fatty acids found in the total lipid fractions ...
DOI:
10.2989/1814232X.2011.572360

5. Modelling regime shifts in the southern Benguela: a frame-based approach

Author:
MD Smith; A Jarre
Source:
African journal of marine science 2011 v.33 no.1 pp. 17-35
ISSN:
1814-2338
Subject:
Engraulis encrasicolus; Sardinops sagax; anchovies; bycatch; climate change; ecosystems; fisheries management; models; pelagic fish; sardines; uncertainty
Abstract:
... This study explores the usefulness of a frame-based modelling approach in the southern Benguela upwelling ecosystem, with four frames describing observed small pelagic fish dominance patterns. We modelled the dynamics of sardine Sardinops sagax and anchovy Engraulis encrasicolus populations under the influence of the small pelagic fishery and climate variability, performed extensive sensitivity an ...
DOI:
10.2989/1814232X.2011.572334

6. Natural markings of Cuvier's beaked whale Ziphius cavirostris in the Mediterranean Sea

Author:
M Rosso; M Ballardini; A Moulins; M Würtz
Source:
African journal of marine science 2011 v.33 no.1 pp. 45-57
ISSN:
1814-2338
Subject:
databases; early development; females; males; photographs; whales; Mediterranean Sea
Abstract:
... Errors in analysis using natural marks have been recognised since the early development of mark-recapture techniques. In this nine-year study, the mark types present on Cuvier's beaked whales Ziphius cavirostris in the Mediterranean Sea were categorised in order to assess the reliability of natural marks for long-term photo-identification studies. Mark prevalence, abundance and gain/loss rates amo ...
DOI:
10.2989/1814232X.2011.572336

7. Seasonal variations of agar extracted from different life stages of Gracilaria cliftonii (Gracilariales, Rhodophyta) from Western Australia

Author:
J Muñoz; R Fotedar
Source:
African journal of marine science 2011 v.33 no.1 pp. 59-65
ISSN:
1814-2338
Subject:
autumn; physicochemical properties; environmental factors; gelatinization temperature; seasonal variation; thallus; melting point; agar; Gracilaria; Western Australia
Abstract:
... Seasonality in yield, physical and chemical properties of the native agar from different life stages of Gracilaria cliftonii was investigated over a period of six seasons (autumn 2008–winter 2009). Agar yield and its properties varied as a function of seasons and life stages but there was no significant correlation between environmental factors and agar properties (p > 0.05). Native agar varied fr ...
DOI:
10.2989/1814232X.2011.572337

8. A stranding of Balaenoptera borealis (Lesson 1828) from Patagonia, Argentina, with notes on parasite infestation and diet

Author:
MS Leonardi; MF Grandi; NA García; G Svendsen; MA Romero; R González; EA Crespo
Source:
African journal of marine science 2011 v.33 no.1 pp. 177-179
ISSN:
1814-2338
Subject:
Anisakis simplex; Balaenoptera borealis; Cestoda; Crustacea; Trematoda; coasts; diet; parasites; parasitoses; stomach; whales; Argentina; Atlantic Ocean
Abstract:
... Strandings of baleen whales are uncommon in Patagonia, Argentina. We report on a stranding of an individual sei whale Balaenoptera borealis on the east coast of San Antonio (40°43.5′ S, 64°55.8′ W), Río Negro province, Argentina. It was the eighth reported stranding of this species along the Argentinean coastline. The stomach content of the whale was dominated by crustaceans. Three parasite specie ...
DOI:
10.2989/1814232X.2011.572384

9. Allozyme and mtDNA variation of white seabream Diplodus sargus populations in a transition area between western and eastern Mediterranean basins (Siculo-Tunisian Strait)

Author:
M Kaouèche; L Bahri-Sfar; M González-Wangüemert; Á Pérez-Ruzafa; OK Ben Hassine
Source:
African journal of marine science 2011 v.33 no.1 pp. 79-90
ISSN:
1814-2338
Subject:
Diplodus; allozymes; basins; cytochrome b; demography; loci; mitochondrial DNA
Abstract:
... To investigate the possible influence of the Siculo-Tunisian Strait on the genetic structure of white seabream Diplodus sargus, 13 polymorphic allozyme loci and a fragment of the cytochrome b mito-chondrial DNA were analysed. Allozyme data indicated a moderate but significant differentiation between some north-eastern (Bizerta, Ghar El Melh Lagoon and Mahdia) and southern (Gabes Gulf and El Biban ...
DOI:
10.2989/1814232X.2011.572342

10. An alternative method for estimating the status of resident reef fish stocks, based on differential fishing effort across a marine reserve boundary

Author:
A Götz; SE Kerwath; CG Attwood; WHH Sauer
Source:
African journal of marine science 2011 v.33 no.1 pp. 107-113
ISSN:
1814-2338
Subject:
biomass; fish; models; mortality; sport fishing; surveys; Africa
Abstract:
... The stock status of roman Chrysoblephus laticeps was estimated in the Goukamma, a temperate South African marine protected area (MPA). Standardised catch per unit effort (CPUE) from a controlled angling survey on both sides of the MPA border was employed to extrapolate the CPUE at zero fishing mortality. Converted into biomass, the estimate (61% of unexploited biomass) lay midway between those of ...
DOI:
10.2989/1814232X.2011.572357

11. Assessment of current data for the octopus resource in Rodrigues, western Indian Ocean

Author:
WHH Sauer; W Potts; D Raberinary; J Anderson; MJ Sylvio Perrine
Source:
African journal of marine science 2011 v.33 no.1 pp. 181-187
ISSN:
1814-2338
Subject:
adults; data collection; models; population size; Indian Ocean; Mauritius
Abstract:
... The annual catch of octopus in the Rodrigues Lagoon, located east/north-east of Mauritius, has dropped by almost half since 1994. This has prompted concern over the resource and has initiated an assessment of the current status of the stock. The limited available biological information suggests that the main pulse of recruitment into the lagoon occurs in the first few months of the year, but that ...
DOI:
10.2989/1814232X.2011.572386

12. Biology, fisheries and distribution of Thryssa vitrirostris (Gilchrist & Thompson 1908) and other Engraulidae along the coast of the Sofala Bank, western Indian Ocean

Author:
D Mualeque; J Santos
Source:
African journal of marine science 2011 v.33 no.1 pp. 127-137
ISSN:
1814-2338
Subject:
Stolephorus; Thryssa vitrirostris; bycatch; coasts; fish; rain; reproduction; turbidity; wet season; Indian Ocean; Mozambique
Abstract:
... The Sofala Bank (16°–21° S) forms a major discontinuity in the gradients of engraulid distribution along the south-eastern African coast. Although the number of species declines southwards, the density and the catches of species associated with higher turbidity increases within the bank, particularly for Thryssa vitrirostris and a few other Thryssa and Stolephorus species. Thryssa vitrirostris for ...
DOI:
10.2989/1814232X.2011.575108

13. Collapse of South Africa's penguins in the early 21st century

Author:
RJM Crawford; R Altwegg; BJ Barham; PJ Barham; JM Durant; BM Dyer; D Geldenhuys; AB Makhado; L Pichegru; PG Ryan; LG Underhill; L Upfold; J Visagie; LJ Waller; PA Whittington
Source:
African journal of marine science 2011 v.33 no.1 pp. 139-156
ISSN:
1814-2338
Subject:
Engraulis encrasicolus; Sardinops sagax; Spheniscus; adults; anchovies; biomass; breeding; fisheries; penguins; sardines; survival rate; South Africa
Abstract:
... The number of African penguins Spheniscus demersus breeding in South Africa collapsed from about 56 000 pairs in 2001 to some 21 000 pairs in 2009, a loss of 35 000 pairs (>60%) in eight years. This reduced the global population to 26 000 pairs, when including Namibian breeders, and led to classification of the species as Endangered. In South Africa, penguins breed in two regions, the Western Cape ...
DOI:
10.2989/1814232X.2011.572377

14. Cross-shelf observations of diet and diel feeding behaviour of the bearded goby Sufflogobius bibarbatus off Namibia

Author:
M Hundt; AC Utne-Palm; MJ Gibbons
Source:
African journal of marine science 2011 v.33 no.1 pp. 119-126
ISSN:
1814-2338
Subject:
Bacillariophyceae; Sufflogobius bibarbatus; coasts; diet; digestion; feeding behavior; fish; habitats; oxygen; zooplankton; Namibia
Abstract:
... The diet of the bearded goby Sufflogobius bibarbatus was studied at two 48 h stations off the Namibian coast. The inner station (120 m) was characterised by a deep layer of low-oxygen bottom water (<0.5 ml DO l⁻¹ or <10% oxygen saturation) scarcely inhabited by metazoan animal life. Gobies at this station were ∼75 mm total length (TL) and displayed a strong vertical size gradient. The diet of all ...
DOI:
10.2989/1814232X.2011.572365

15. Feeding and ecomorphology of seven flatfish species in the North-North-West Aegean Sea, Greece

Author:
PK Karachle; KI Stergiou
Source:
African journal of marine science 2011 v.33 no.1 pp. 67-78
ISSN:
1814-2338
Subject:
Arnoglossus laterna; Citharus linguatula; Crustacea; Polychaeta; Symphurus; diet; fish; fisheries; gillnets; intestines; invertebrates; mouth; multivariate analysis; trophic relationships; Aegean Sea; Greece
Abstract:
... The diet composition and possible relationships between mouth area and intestine length with feeding were investigated for seven flatfish species in the North-North-West Aegean Sea. Samples were obtained from commercial fisheries (trawls and gillnets) on a seasonal basis, and a total of 444 individuals was analysed. The two most abundant species, Arnoglossus laterna and Citharus linguatula, preyed ...
DOI:
10.2989/1814232X.2011.572338

16. Noteworthy elasmobranch records from Oman

Author:
AC Henderson; AJ Reeve
Source:
African journal of marine science 2011 v.33 no.1 pp. 171-175
ISSN:
1814-2338
Subject:
Carcharhinus; Centrophorus; Ctenacis; Paragaleus; Rhinobatos; Sphyrna; Oman
Abstract:
... Records of 11 elasmobranch species previously unreported from, or uncommon in, Omani waters are presented. Records new to Oman include Carcharhinus altimus, C. leiodon, Centrophorus isodon, Ctenacis fehlmanni, Himantura fai, Mobula eregoodootenke and Sphyrna zygaena, whereas noteworthy records of uncommon species include Himantura imbricata, Paragaleus randalii, Rhinobatos salalah and Taeniura mey ...
DOI:
10.2989/1814232X.2011.572380

17. Prey and seasonal abundance of killer whales at sub-Antarctic Marion Island

Author:
RR Reisinger; PJN de Bruyn; CA Tosh; WC Oosthuizen; NT Mufanadzo; MN Bester
Source:
African journal of marine science 2011 v.33 no.1 pp. 99-105
ISSN:
1814-2338
Subject:
Arctocephalus; Mirounga leonina; Orcinus orca; diet; penguins; predation; seals
Abstract:
... The diet of killer whales Orcinus orca was investigated from 48 predation events observed during 823 sightings at sub-Antarctic Marion Island between 2006 and 2009. From these events, there were 10 cases where prey could be identified. Killer whales fed on fur seals Arctocephalus tropicalis, elephant seals Mirounga leonina and penguins. Constant effort (dedicated) observations (259 hours, 2008–200 ...
DOI:
10.2989/1814232X.2011.572356

18. The waters of São Tomé: a calving ground for West African humpback whales?

Author:
I Carvalho; C Brito; ME dos Santos; HC Rosenbaum
Source:
African journal of marine science 2011 v.33 no.1 pp. 91-97
ISSN:
1814-2338
Subject:
Megaptera novaeangliae; breeding season; breeding sites; calves; calving; group size; mating frequency; summer; surveys; winter; Antarctic region; Gulf of Guinea
Abstract:
... In the Southern Hemisphere, humpback whales Megaptera novaeangliae feed in Antarctic waters during the austral summer and migrate to their breeding grounds in subtropical and tropical waters during the winter. Historical whaling records suggest that the Archipelago of São Tomé and Príncipe, located in the Gulf of Guinea, serves as a possible breeding ground. In order to investigate the temporal oc ...
DOI:
10.2989/1814232X.2011.572353