scholarly journals Movement patterns and growth rate of cavebass Dinoperca petersi (Pisces: Dinopercidae) in the iSimangaliso Marine Protected Area, South Africa

2021 ◽  
Vol 19 (2) ◽  
pp. 45-59
Author(s):  
Bruce Q. Mann ◽  
Gareth L. Jordaan ◽  
Ryan Daly
Keyword(s):  
South Africa ◽  
Growth Rate ◽  
Protected Area ◽  
Marine Protected Area ◽  
Movement Patterns ◽  
Home Range Size ◽  
Average Growth ◽  
Kwazulu Natal ◽  
High Site

Dinoperca petersi is a relatively common fish species caught in the line-fishery in KwaZulu-Natal (KZN), South Africa. Yet, little is known about the biology and ecology of this species. Movement patterns and growth rate of this species were studied based on data obtained from a long-term tag-recapture study conducted in the iSimangaliso Marine Protected Area in northern KZN between 2001-2019. Results showed that D. petersi is a highly resident species with a linear home-range size of 290-405 m. While most fish showed high site fidelity, 8.8 % of the tagged fish showed wider ranging movements of 2.4-90 km. However, only 5 fish showed movements out of no-take zones into adjacent exploited areas, suggesting limited adult spillover. Growth rate of tagged fish was found to be reasonably slow compared to other sympatric predatory reef fish with an average growth rate of 61.76 mm y–1 for smaller fish (gα = 300) and 9.58 mm y–1 for larger fish (gβ = 550). Based on these life history characteristics, options for the future conservation and management of this species are discussed.

Evaluating conditions for successful co-management of subsistence fisheries in KwaZulu-Natal, South Africa

2005 ◽  
Vol 32 (2) ◽  
pp. 165-177 ◽  
Author(s):  
VICTORIA R. NAPIER ◽  
GEORGE M. BRANCH ◽  
JEAN M. HARRIS
Keyword(s):  
South Africa ◽  
Rural Communities ◽  
National Government ◽  
Strongly Correlated ◽  
Local Institutions ◽  
Top Down ◽  
Subsistence Fisheries ◽  
Perceived Success ◽  
Kwazulu Natal

Conditions important for the success of co-management have repeatedly been identified, but their relative influence has not been quantitatively evaluated. To investigate the implementation of co-management in 11 subsistence fisheries within seven rural communities in KwaZulu-Natal, South Africa, perceptions of the responsible authorities and the fishing communities were surveyed. Of 16 conditions often considered important for the success of co-management, only nine were correlated with perceived success, the most strongly correlated being (1) benefits of co-management must exceed costs of participation, (2) training and empowerment, and (3) existence of a long-term ‘champion’ to drive the process. The perceptions of the authorities concurred with those of the communities with regards to the attainment of conditions, but views on the success of co-management differed significantly owing to disagreements that were specific to three particular fisheries. Both groups agreed that co-management is a viable improvement on top-down authoritarian imposition of regulations. However, it takes time to become effective; perceived success was directly correlated with how long individual programmes had been operating. Failure to devolve power from national government to local institutions, and delays in awarding subsistence permits, remain the major stumbling blocks to full realization of co-management.

scholarly journals Preliminary assessment of surf-zone and estuarine line-fish species of the Dwesa-Cwebe Marine Protected Area, Eastern Cape, South Africa

Koedoe ◽  
2012 ◽  
Vol 54 (1) ◽  
Author(s):  
Jan A. Venter ◽  
Bruce Q. Mann
Keyword(s):  
South Africa ◽  
Law Enforcement ◽  
Fish Species ◽  
Protected Area ◽  
Surf Zone ◽  
Marine Protected Area ◽  
Fish Populations ◽  
Estuarine Fish ◽  
Catch Per Unit Effort ◽  
Preliminary Assessment

A preliminary assessment of surf-zone and estuarine line fish was carried out in the DwesaCwebe Marine Protected Area (MPA), on the Wild Coast, South Africa. The purpose was to provide baseline data on inshore line-fish stocks in the MPA. A total of 28 species was recorded, of which 53% have a conservation status reflecting some concern and 43% are endemic to southern Africa. This highlights the value of the MPA for protection of important line-fish species. Within the MPA, localised differences were detected in species diversity, size frequency and catch per unit effort between unexploited and illegally exploited areas. These differences were more prominent in slow growing, long-lived species. It thus appears that illegal exploitation is negatively affecting fish populations within the MPA, which counteract and potentially could eliminate the benefits of fish protection typically associated with no-take MPAs. These results highlight the need for improved law enforcement and better communication with neighbouring communities to increase awareness. It is further recommended that the current no-take status of the MPA should be maintained. In addition, baseline fisheries information was collected on certain fish species that could be used to inform future conservation management of the MPA.Conservation implications: The Dwesa-Cwebe Marine Protected Area is unique and important for the conservation of key surf zone and estuarine fish species. However there is a significant risk to the fish populations due to illegal exploitation. Key interventions should include enhanced law enforcement but, more important, the creation of alternative livelihoods and long term sustainable benefits to local communities.

Case Note: The interface between customary rights and environmental legislation: Lessons from Gongqose & Others vs Minister of Agriculture, Forestry and Fisheries & Others (SCA) 2018

2020 ◽  
Vol 26 ◽  
pp. 134-160
Author(s):  
Alexander Paterson
Keyword(s):  
South Africa ◽  
Natural Resources ◽  
Protected Area ◽  
Marine Protected Area ◽  
Customary Law ◽  
Constitutional Court ◽  
Eastern Cape ◽  
Customary Rights ◽  
The Republic ◽  
Law And Legislation

The Constitution of the Republic of South Africa, 1996, recognises customary law as an independent and original source of law, subject to the Constitution itself and legislation that specifically deals with customary law. As recognised by the Constitutional Court in Alexkor Ltd vs the Richtersveld Community (2004), customary law, as an independent source of law, may give rise to rights including rights to access and use natural resources. Rights to access and use natural resources are often comprehensively regulated by legislation. Conflicts between customary law and legislation relevant to natural resources may arise, as evidenced in the case of Mr Gongqose, who along with several other community members were caught fishing in the Dwesa-Cwebe Marine Protected Area situated off the Eastern Cape coastline. Notwithstanding their claims to be exercising their customary rights to fish in the area, they were convicted in the Magistrate’s Court for certain offences in terms of the Marine Living Resources Act (1998), under which the marine protected area had been established. Their appeal to the High Court proved unsuccessful and the Supreme Court of Appeal was tasked with considering the relationship between their customary rights to fish and legislation purportedly extinguishing these rights. The SCA’s judgment in Gongqose & Others vs Minister of Agriculture, Forestry and Fisheries & Others (2018) is the first of its kind in South Africa to consider the extinguishment of customary rights to access and use natural resources through post-constitutional legislation. This note critically considers the guidance the SCA provided on proving the existence of customary rights to access and use natural resources, and the manner in which they may be extinguished through legislation. While the focus is on marine living resources, the lessons emerging from this case are relevant to other natural resource sectors.

scholarly journals The rebirth and evolution of Bezymianny volcano, Kamchatka after the 1956 sector collapse

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Alina V. Shevchenko ◽  
Viktor N. Dvigalo ◽  
Thomas R. Walter ◽  
Rene Mania ◽  
Francesco Maccaferri ◽  
...  
Keyword(s):  
Growth Rate ◽  
Numerical Modeling ◽  
Volcanic Activity ◽  
Summit Crater ◽  
Sector Collapse ◽  
Average Growth Rate ◽  
Average Growth ◽  
Bezymianny Volcano ◽  
Lava Domes

Abstract Continued post-collapse volcanic activity can cause the rise of a new edifice. However, details of such edifice rebirth have not been documented yet. Here, we present 7-decade-long photogrammetric data for Bezymianny volcano, Kamchatka, showing its evolution after the 1956 sector collapse. Edifice rebirth started with two lava domes originating at distinct vents ~400 m apart. After 2 decades, activity became more effusive with vents migrating within ~200 m distance. After 5 decades, the activity focused on a single vent to develop a stratocone with a summit crater. We determine a long-term average growth rate of 26,400 m3/day, allowing us to estimate the regain of the pre-collapse size within the next 15 years. Numerical modeling explains the gradual vents focusing to be associated with loading changes, affecting magma pathways at depth. This work thus sheds light on the complex regrowth process following a sector collapse, with implications for regrowing volcanoes elsewhere.

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