Fish communities of the Wilderness Lakes System in the southern Cape, South Africa

The Wilderness Lakes System, a temporarily open and closed estuary with three associated lakes situated in the southern Cape region of South Africa, was sampled using a range of sampling gears to assess the fish community. A total of 25 species were sampled throughout the system, with the highest diversity in the Touw Estuary (23 species) and the lowest in Langvlei (11 species). Estuary-associated marine species (13 species) dominated species richness with smaller proportions of estuarine resident (7 species), freshwater (3 species) and catadromous species (2 species). Estuarine resident species dominated the catch numerically. The size–class distribution of euryhaline marine species indicated that upon entering the Touw Estuary as juveniles, the fish move up the system towards Rondevlei where they appear to remain. Three freshwater species were recorded in the system, all of which are alien to the Wilderness Lakes System. Decreasing salinity in the upper lakes appears to be a driving factor in the distribution and increasing abundance of the freshwater fishes. Sampling followed a drought, with the system experiencing substantially increased levels of mouth closure compared to a similar study conducted in the 1980s. The timing of mouth opening and the degree of connectivity between the lakes influence the nursery function of the system as a whole. Management actions need to focus on improving ecological functioning of this system, in particular how mouth opening is managed, to facilitate nursery function and limit the establishment of invasive species.Conservation implications: Key management actions are required to improve fish recruitment potential into and within the system. These include maintenance of adequate marine inflow through adherence to artificial mouth breaching protocols and improving connectivity between the lakes through sediment removal from localised deposition points within the connecting channels.

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A survey of the ichthyofauna in the Noetsie Estuary, Western Cape Province, South Africa

Koedoe ◽

10.4102/koedoe.v60i1.1513 ◽

2018 ◽

Vol 60 (1) ◽

Author(s):

Martin K.S. Smith ◽

Demi Rodrigues ◽

Bianca Currie

Keyword(s):

South Africa ◽

Fish Species ◽

Late Summer ◽

Marine Species ◽

Ecological Condition ◽

Estuarine Fish ◽

Freshwater Species ◽

Western Cape ◽

Species List ◽

Estuarine Resident

The fish assemblage in the Noetsie Estuary, a temporarily open and closed estuary on the southern coast of South Africa, was sampled using multiple gears. A total of 12 species from 8 families were recorded. Collectively, estuarine-dependent marine species dominated seine net catches numerically and in terms of biomass for both sampling seasons. Estuarine round herring (Gilchristella aestuaria) was numerically the dominant species in late summer, while juvenile Mugilidae dominated catches in winter. Size class distributions of various fish species indicate that the estuary both serves a nursery function for important euryhaline marine species and supports estuarine resident taxa. Application of the Estuarine Fish Community Index indicates the ecological condition of the estuary to be ‘good’. This study contributes to the species list for the estuary while also reporting the presence of an alien invasive freshwater species, Gambusia affinis. Recommendations include the development of a management plan and the formalisation of an estuarine management committee.Conservation implications: The Noetsie Estuary serves a nursery function for important euryhaline marine species, while supporting healthy populations of estuarine resident taxa. The presence of one alien invasive fish species is documented with potential implications for the conservation of biodiversity in the estuary.

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Continental vs. Global Niche-Based Modelling of Freshwater Species’ Distributions: How Big Are the Differences in the Estimated Climate Change Effects?

Water ◽

10.3390/w13060816 ◽

2021 ◽

Vol 13 (6) ◽

pp. 816

Author(s):

Danijela Markovic ◽

Jörg Freyhof ◽

Oskar Kärcher

Keyword(s):

Climate Change ◽

Thermal Properties ◽

Safety Margin ◽

Thermal Response ◽

Future Climate Change ◽

Freshwater Species ◽

Response Curves ◽

Preferred Temperature ◽

Continental Scale ◽

Management Actions

Thermal response curves that depict the probability of occurrence along a thermal gradient are used to derive various species’ thermal properties and abilities to cope with warming. However, different thermal responses can be expected for different portions of a species range. We focus on differences in thermal response curves (TRCs) and thermal niche requirements for four freshwater fishes (Coregonus sardinella, Pungitius pungitius, Rutilus rutilus, Salvelinus alpinus) native to Europe at (1) the global and (2) European continental scale. European ranges captured only a portion of the global thermal range with major differences in the minimum (Tmin), maximum (Tmax) and average temperature (Tav) of the respective distributions. Further investigations of the model-derived preferred temperature (Tpref), warming tolerance (WT = Tmax − Tpref), safety margin (SM = Tpref − Tav) and the future climatic impact showed substantially differing results. All considered thermal properties either were under- or overestimated at the European level. Our results highlight that, although continental analyses have an impressive spatial extent, they might deliver misleading estimates of species thermal niches and future climate change impacts, if they do not cover the full species ranges. Studies and management actions should therefore favor whole global range distribution data for analyzing species responses to environmental gradients.

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Is the water permit system a panacea or a bed of inefficiency? The case of South Africa

Water Policy ◽

10.2166/wp.2013.021 ◽

2013 ◽

Vol 15 (4) ◽

pp. 570-584 ◽

Cited By ~ 1

Author(s):

Devi Datt Tewari ◽

Saidou Baba Oumar

Keyword(s):

South Africa ◽

Water Distribution ◽

Water Markets ◽

Water Management System ◽

Administrative Costs ◽

System A ◽

Access To Water ◽

License System ◽

Institutional Efficiency

Although South Africa has adopted a very modern permit/license system to control access to water as a resource, the attainment of the lofty objectives (efficiency, equity and sustainability) of the National Water Act of 1998 depends on two critical factors: (1) the institutional efficiency of the water management system; and (2) the development of water markets and their efficient functioning. This study lists a number of concerns that the Act is not geared to resolve efficiently or in a timely manner. These concerns include the high administrative costs of implementation, poor incentives for long-term investments, bureaucratic inefficiency, practical problems in water pricing and adaptability to climate change threat. There is a need to re-think the ways and means with which to make water distribution more efficient in the country. One possible solution would be to develop water markets in the country.

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In Search of the Perceived Quality and Impact of Accredited South African Law Journals: Exploring the Possibility of a Ranking System. A Baseline Study: 2009 – 2014

Potchefstroom Electronic Law Journal/Potchefstroomse Elektroniese Regsblad ◽

10.17159/1727-3781/2018/v21i0a3459 ◽

2018 ◽

Vol 21 ◽

pp. 1-50

Author(s):

Marita Carnelley

Keyword(s):

South Africa ◽

South African ◽

Research Output ◽

Rejection Rate ◽

Journal Ranking ◽

Bibliometric Data ◽

Ranking System ◽

System A ◽

Ranking Systems ◽

Minimum Requirements

The DHET Research Output Policy (2015) indicates that there has been a change in the government’s approach to research funding. Previously all research published in any accredited journal was rewarded equally. A decision has been taken, however, that a shift will be made towards rewarding better quality and higher impact peer-review research. Additional mechanisms such as biometric/bibliometric data, including citations, assessments by discipline-specific panels of experts and/or post-publication reviews may be used to determine the quality and impact of publications. The policy notes that the DHET may distinguish between "high" and "low" impact journals after proper consultation. This article highlights the need for consultation by the legal fraternity with the DHET about the implementation of these possible mechanisms in the light of the special considerations applicable to the evaluation of law journals: most journals publish mainly local legal content, there is a limited number of active legal academics, the nature of legal research is not empirical, and a premium is placed on the writing of books. The research evaluates the available data between 2009 and 2014 in an attempt to assess if it would be appropriate to introduce a legal journal ranking system in South Africa. The article discusses direct and indirect forms of quality evaluation to inform possible ranking systems. This includes the data from the ASSAf expert panel evaluation of law journals in 2014 and other bibliometric data based on whether the journal is featured in international accredited lists, the size of its print-run, author prominence, rejection-rate, usage studies, and evaluations based on citations. An additional ranking system is considered, based on the five best outputs submitted to the National Research Foundation by applicants applying for rating. The article concludes that a law journal ranking system would be inappropriate for South Africa. None of the systems meet the minimum requirements for a trustworthy ranking of South African law journals, as the data available are insufficient, non-verifiable and not based on objective quality-sensitive criteria. Consultation with the DHET is essential and urgent to avoid the implementation of inappropriate measures of quality and impact assessmen

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The Ocean Pout, Zoarces americanus, and the Ocean Sunfish, Mola mola: Additions to the Marine Ichthyofauna of the Lower Saint John River System, New Brunswick, with a Summary of Marine Fish Reported from the Estuary

The Canadian Field-Naturalist ◽

10.22621/cfn.v127i1.1405 ◽

2013 ◽

Vol 127 (1) ◽

pp. 38 ◽

Cited By ~ 1

Author(s):

Donald F. McAlpine

Keyword(s):

New Brunswick ◽

River System ◽

Marine Species ◽

Sensu Stricto ◽

Marine Fishes ◽

Ocean Sunfish ◽

System A ◽

Mola Mola ◽

Saint John ◽

The Status

Recent records for the Ocean Pout, Zoarces americanus (collected 11 February 2011), and the Ocean Sunfish, Mola mola (photograph taken 24 June 2012), in the lower Saint John River system, New Brunswick, add to the list of marine fishes reported from this oceanographically unique estuary system. A total of 62 species of strictly freshwater, anadromous, catadromous, and marine fishes have now been recorded in the Saint John River system, with 49 of these in the Saint John River sensu stricto. The Acadian Redfish, Sebastes faciatus, a species assessed as threatened by the Committee on the Status of Endangered Wildlife in Canada, appears to be among these. While strictly marine fishes may contribute relatively little to the overall biomass of fishes in the Saint John River system, marine species account for 30.6% of the biodiversity of fishes in the river to date. This suggests that marine fishes may be a more significant component of the ichthyofauna of the lower Saint John River system than is generally recognized.

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Contrasting Toxin Selectivity between the Marine Pufferfish Takifugu pardalis and the Freshwater Pufferfish Pao suvattii

Toxins ◽

10.3390/toxins11080470 ◽

2019 ◽

Vol 11 (8) ◽

pp. 470 ◽

Cited By ~ 7

Author(s):

Wei Gao ◽

Yoko Kanahara ◽

Misako Yamada ◽

Ryohei Tatsuno ◽

Hiroyuki Yoshikawa ◽

...

Keyword(s):

Marine Species ◽

The Body ◽

Freshwater Species ◽

Oral Gavage ◽

Paralytic Shellfish Poison ◽

Toxin Content ◽

Paralytic Shellfish ◽

Strong Contrast

To clarify the differences in toxin selectivity between marine and freshwater pufferfish, we conducted experiments in artificially reared nontoxic specimens of Takifugu pardalis (marine) and Pao suvattii (freshwater) using tetrodotoxin (TTX) and paralytic shellfish poison (PSP; decarbamoylsaxitoxin (dcSTX) or saxitoxin (STX)). T. pardalis specimens were administered feed homogenate containing TTX or dcSTX (dose of toxin, 55.2 nmol/fish) and P. suvattii specimens were administered feed homogenate containing TTX + STX (dose of each toxin, 19.2 nmol/fish) by oral gavage. The toxin content in the intestine, muscle, skin, liver, and gonads was quantified after 24 and 48 or 72 h. In T. pardalis, TTX administered into the intestine was absorbed into the body and transferred and retained mainly in the skin and liver, while dcSTX was hardly retained in the body, although it partly remained in the intestine. In strong contrast, in P. suvattii, little TTX remained in the body, whereas STX was absorbed into the body and was transferred and retained in the ovary and skin. The findings revealed that TTX/PSP selectivity differs between the marine species T. pardalis and the freshwater species P. suvattii. T. pardalis, which naturally harbors TTX, selectively accumulates TTX, and P. suvattii, which naturally harbors PSP, selectively accumulates PSP.

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Law in and Legitimacy South Africa

Law & Social Inquiry ◽

10.1111/j.1747-4469.1995.tb01068.x ◽

1995 ◽

Vol 20 (02) ◽

pp. 407-479

Author(s):

Stephen Ellmann

Keyword(s):

South Africa ◽

Legal System ◽

New South ◽

The South ◽

Men And Women ◽

System A

This mticle examines whether anti-apartheid lawyering might have legitimized the South Afncan legal system by asking what black South Ahcans actually thought of that system. Perhaps surprisingly, blrcks, and in particular African, appear to have accorded the legal system a measure of legitimacy despite the oppression they often suffered at its hands. Three paradigms of African opinion are offered to help us understand the complex African response to the legal system: the conservatives, forbearing, mutely concerned with such issues as order and security, and perhaps disposed to be deferential to institutions of white authority; the speakers, fueled by faith in the truth or power of their speech, and welcoming the opportunity to be heard that courts could povide; and the activists, adamantly detennined to bnng down apartheid, and judgrng institutions and people by their conhibution to that goal. For men and women thinking in these ways, anti-apartheid lawyering probably did contribute to legitimizing the legal system and that system's ideals. But this partial legitimation of the legal system is, in the end, no came for regret; instead, it may have helped the new South Africa begin building a nation governed by law.

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Two New Hyporheic Amphipods, Bogidiella ( Bogidiella) Cyrnensis n. sp. and Bogidiella (Medigidiella?) Paolii n. sp., from Corsica

Bijdragen tot de Dierkunde ◽

10.1163/26660644-05301005 ◽

1983 ◽

Vol 53 (1) ◽

pp. 82-92 ◽

Cited By ~ 1

Author(s):

F. Hovenkamp ◽

W. Hovenkamp ◽

J.J. van der Heide

Keyword(s):

New Species ◽

Marine Species ◽

Small Rivers ◽

Amphipod Species ◽

Freshwater Species ◽

The Family ◽

The Mediterranean

Two new amphipod species of the family Bogidiellidae were found in the hyporheal of two small rivers on Corsica. Both new species, Bogidiella (Bogidiella) cyrnensis n. sp. and B. paolii n. sp. (provisionally placed in the subgenus Medigidiella, but a definitive classification will have to wait till males are found), encountered at altitudes of 135 m and 750 m, respectively, show more affinities with certain freshwater species of Sardinia than with marine species of the Mediterranean.

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