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Humpback whales (Megaptera novaeangliae) in the Southeastern Atlantic Ocean (International Whaling Commission 'Breeding Stock B'--BSB) are distributed from the Gulf of Guinea to Western South Africa. Genetic data suggest that this stock may be sub-structured, but it remains unknown if this is due to reproductive segregation. This paper evaluates the spatial and temporal population structure of BSB humpback whales using a combination of maternally and bi-parentally inherited markers. The genetic differentiation that we identify in this study could be due to a combination of (1) spatial and/or temporal segregation on breeding grounds in the greater Gulf of Guinea, (2) the possibility of maternally inherited site fidelity to specific feeding grounds and (3) the use of two generalized but exclusive migratory routes (coastal and offshore) between feeding and breeding areas. Further, photo-identification and genetic sampling efforts in other areas of the Sub-Saharan Western Africa winter range and targeted deployment of satellite tags would help to clarify some of the apparent complexity in the population structure of animals biopsied in this region., Introduction Understanding the processes by which marine populations diverge or remain homogeneous remains a major challenge in evolutionary biology. The accurate description of population genetic structure over a species geographic [...]

Southern Hemisphere humpback whales (Megaptera novaeangliae) generally undertake annual migrations from polar summer feeding grounds to winter calving and nursery grounds in subtropical and tropical coastal waters. Evidence for such migrations arises from seasonality of historic whaling catches by latitude, Discovery and natural mark returns, and results of satellite tagging studies. Feeding is generally believed to be limited to the southern polar region, where Antarctic krill (Euphausia superba) has been identified as the primary prey item. Non-migrations and / or suspended migrations to the polar feeding grounds have previously been reported from a summer presence of whales in the Benguela System, where feeding on euphausiids (E. lucens), hyperiid amphipods (Themisto gaudichaudii), mantis shrimp (Pterygosquilla armata capensis) and clupeid fish has been described. Three recent research cruises (in October/November 2011, October/November 2014 and October/November 2015) identified large tightly-spaced groups (20 to 200 individuals) of feeding humpback whales aggregated over at least a one-month period across a 220 nautical mile region of the southern Benguela System. Feeding behaviour was identified by lunges, strong milling and repetitive and consecutive diving behaviours, associated bird and seal feeding, defecations and the pungent “fishy” smell of whale blows. Although no dedicated prey sampling could be carried out within the tightly spaced feeding aggregations, observations of E. lucens in the region of groups and the full stomach contents of mantis shrimp from both a co-occurring predatory fish species (Thyrsites atun) and one entangled humpback whale mortality suggest these may be the primary prey items of at least some of the feeding aggregations. Reasons for this recent novel behaviour pattern remain speculative, but may relate to increasing summer humpback whale abundance in the region. These novel, predictable, inter-annual, low latitude feeding events provide considerable potential for further investigation of Southern Hemisphere humpback feeding behaviours in these relatively accessible low-latitude waters. [ABSTRACT FROM AUTHOR]

Elucidating patterns of population structure for species with complex life histories, and disentangling the processes driving such patterns, remains a significant analytical challenge. Humpback whale ( Megaptera novaeangliae) populations display complex genetic structures that have not been fully resolved at all spatial scales. We generated a data set of nuclear markers for 3575 samples spanning the seven breeding stocks and substocks found in the South Atlantic and western and northern Indian Oceans. For the total sample, and males and females separately, we assessed genetic diversity, tested for genetic differentiation between putative populations and isolation by distance, estimated the number of genetic clusters without a priori population information and estimated rates of gene flow using maximum-likelihood and Bayesian approaches. At the ocean basin scale, structure is governed by geographical distance ( IBD P < 0.05) and female fidelity to breeding areas, in line with current understanding of the drivers of broadscale population structure. Consistent with previous studies, the Arabian Sea breeding stock was highly genetically differentiated ( FST 0.034-0.161; P < 0.01 for all comparisons). However, the breeding stock boundary between west South Africa and east Africa was more porous than expected based on genetic differentiation, cluster and geneflow analyses. Instances of male fidelity to breeding areas and relatively high rates of dispersal for females were also observed between the three substocks in the western Indian Ocean. The relationships between demographic units and current management boundaries may have ramifications for assessments of the status and continued protections of populations still in recovery from commercial whaling. [ABSTRACT FROM AUTHOR]

Stewardship is a popular term for the principles and actions aimed at improving sustainability and resilience of social-ecological systems at various scales and in different contexts. Participation in stewardship is voluntary, and is based on values of altruism and long-term benefits. At a global scale, 'earth stewardship' is viewed as a successor to earlier natural resource management systems. However, in South Africa, stewardship is narrowly applied to biodiversity conservation agreements on private land. Using a broader definition of stewardship, we identify all potentially related schemes that may contribute to sustainability and conservation outcomes. Stewardship schemes and actors are represented as a social network and placed in a simple typology based on objectives, mechanisms of action and operational scales. The predominant type was biodiversity stewardship programmes. The main actors were environmental non-governmental organisations participating in prominent bioregional landscape partnerships, together acting as important 'bridging organisations' within local stewardship networks. This bridging enables a high degree of collaboration between non-governmental and governmental bodies, especially provincial conservation agencies via mutual projects and conservation objectives. An unintended consequence may be that management accountability is relinquished or neglected by government because of inadequate implementation capacity. Other stewardship types, such as market-based and landscape initiatives, complemented primarily biodiversity ones, as part of national spatial conservation priorities. Not all schemes related to biodiversity, especially those involving common pool resources, markets and supply chains. Despite an apparent narrow biodiversity focus, there is evidence of diversification of scope to include more civic and community-level stewardship activities, in line with the earth stewardship metaphor. [ABSTRACT FROM AUTHOR]

Conservation targets are useful policy tools, indicating a degree of political intent and allowing purposeful conservation planning. However, target setting and implementation often occur at different scales. A largely unmet challenge is to establish mutual feedbacks between national-scale target setting and local-scale ecological realities and management actions., Freshwater conservation in South Africa has been advanced through the participatory setting of a freshwater conservation target (20% of each freshwater ecosystem type). This paper presents the response of a conservation agency, South African National Parks, to achieving the national target. In a first step, achievement of the national target was contextualized within the agency's mandate to conserve biodiversity through 19 National Parks. In the second step, information was scaled down further to reflect the relative contribution of an individual park (Tankwa-Karoo National Park) to freshwater conservation in South Africa., At agency level, national-scale data translated into several recommendations to influence the future expansion and design of protected areas, helped to articulate key messages regarding the organization's contribution to meeting national targets, and triggered the development of strategic objectives to promote in-house capacity for effective freshwater conservation. Park-level application of national-scale data informed recommendations for management, research and monitoring. At the same time, local-scale survey data highlighted deficiencies in the national data layers., Establishing feedbacks between top-down setting of conservation targets and bottom-up implementing of management actions is desirable and possible, but also intricate. To promote the establishment of such feedbacks, four generic insights are drawn from this case study: top-down targets and bioregional-scale biodiversity data have enabling utility; effective feedbacks can only be realized through systemic conservation governance; social factors are at least as important as technical advances; national-scale maps are not necessarily accurate but can still be used to facilitate co-learning and dynamic refinement., Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Sense of place (SoP) refers to the meanings and values that people attach to places. The concept can be used to frame how people engage or form a connection with the natural environment. At a sensory level, SoP is influenced by people’s visual experiences, which in turn can be linked to the concept of viewsheds. Viewsheds can be transformed, either abruptly (e.g. by infrastructure development such as wind turbines) or more gradually (e.g. by non-native trees invading a landscape). In this study, we focus on the Garden Route National Park to explore the potential importance of viewsheds as a conservation feature, specifically in the context of non-native (especially invasive) tree species. Using mixed information sources, we explore the potential role of invasive trees on experiences of visitors to this protected area and speculate on how viewsheds may shape SoP associations and how such associations may inform protected area management. Our investigation shows that people’s experiences regarding natural and modified viewsheds are varied and intricate. Both SoP and viewsheds have the potential to inform conservation action, and these concepts should form an integral part of objective hierarchies and management plans for national parks. However, while legislation and park management plans make provision for the use of these concepts, associated research in South Africa is virtually non-existent. We conclude by proposing a conceptual model and research agenda to promote the use of viewsheds and SoP in the management of national parks in South Africa. Conservation implications: Viewshed and sense of place can be used as boundary concepts to (1) facilitate interdisciplinary research between social and natural scientists, (2) help understand the connectedness and feedbacks between people and nature and (3) promote communication between science, management and stakeholders regarding desired conditions of landscapes in and around parks. [ABSTRACT FROM AUTHOR]

The southern right whale's ( Eubalaena australis) demography, occurrence, habitat use, and behavior off South Africa are known predominantly from an ongoing aerial survey data set that started in 1971. The fixed timeframes of these surveys and their geographical bias towards south coast nursery areas have constrained our knowledge about the right whale's seasonal distribution elsewhere. We present shore-based observations and tracking of right whales at Saldanha Bay on the west coast (2001-2003) that reveal a near year-round presence and strongly nearshore distribution. With seasonal progression from winter to summer we observed a gradual increase in sighting rate, reduction in swimming speed, less directionality of movement, an increase in group size, and more surface active groups. The area appears to be important for feeding and socializing but not as a calving or nursery area. Individual transits between the south and west coasts, bidirectional alongshore movements, and extended seasonal presence may all be indicative of reoccupation of their former range along the west coast. This is important given the increasing ship traffic at Saldanha Bay, the rapid expansion of the region's oil and gas industry, and the known vulnerability of the closely related North Atlantic right whale ( E. glacialis) to ship strikes. [ABSTRACT FROM AUTHOR]

Site fidelity is common among migratory cetaceans, including humpback whales (Megaptera novaeangliae). In the Northern Hemisphere it has been found that fidelity to humpback whale feeding grounds is transferred maternally but this has never been shown for the species in the Southern Hemisphere. We examined this in a unique feeding area off west South Africa using resighting data of 68 individually identified humpback whales by means of photographic (tail flukes and dorsal fins) and/or molecular methods (microsatellite genotyping) over an 18 year span. We found short-term association patterns and recurrent visits typical of other feeding grounds. Males and females had different seasonality of attendance. Significant female-dominated presence corresponded to timing of an expected influx of females on their southward migration from the breeding ground: firstly non-nursing (possibly pregnant) females in mid-spring, and mothers and calves in mid-to late summer. The potential benefit of this mid-latitude feeding area for females is illustrated by a record of a cow with known age of at least 23 years that produced calves in three consecutive years, each of which survived to at least six months of age: the first record of successful post-partum ovulation for this species in the Southern Hemisphere. We recorded association of a weaned calf with its mother, and a recurring association between a non-lactating female and male over more than two years. Moreover, three animals first identified as calves returned to the same area in subsequent years, sometimes on the same day as their mothers. This, together with numerous Parent-Offspring relations detected genetically among and between resighted and non-resighted whales is strongly suggestive of maternally derived site fidelity at a small spatial scale by a small sub-population of humpback whales. [ABSTRACT FROM AUTHOR]

von der Heyden, S., Barendse, J., Seebregts, A. J., and Matthee, C. A. 2010. Misleading the masses: detection of mislabelled and substituted frozen fish products in South Africa. – ICES Journal of Marine Science, 67: 176–185.Mislabelling poses a threat to the sustainability of seafood supply chains and, when frequent, can significantly affect conservation efforts. Here we identify the most popular fish in the South African market through consumer and retailer surveys and data gathered by a sustainable seafood campaign. Of these species, we tested a number of widely available and generally high-market priced fish, utilizing mtDNA 16S rRNA sequencing. Tests of 178 samples revealed that about half of all fillets are mislabelled. Most problematic was kob, Argyrosomus spp., for which some 84% of fillets provided belonged to other species, including mackerel, croaker, and warehou. Phylogenetic analyses provided strong support that the fillets sold as barracuda and wahoo were probably king mackerel and that red snapper fillets included fillets of river snapper, Lutjanus argentimaculatus, which is a species prohibited for sale in South Africa. We also discovered substitution of yellowtail for dorado. From preliminary population genetic comparisons, some 30% of kingklip samples probably had their origin in New Zealand, rather than southern Africa. The research revealed a market conducive to mislabelling through poor consumer and retailer awareness, and highlighted the value of sustainable seafood campaigns to draw attention to this. [ABSTRACT FROM PUBLISHER]

Although humpback whales are among the best-studied of the large whales, population boundaries in the Southern Hemisphere (SH) have remained largely untested. We assess population structure of SH humpback whales using 1,527 samples collected from whales at fourteen sampling sites within the Southwestern and Southeastern Atlantic, the Southwestern Indian Ocean, and Northern Indian Ocean (Breeding Stocks A, B, C and X, respectively). Evaluation of mtDNA population structure and migration rates was carried out under different statistical frameworks. Using all genetic evidence, the results suggest significant degrees of population structure between all ocean basins, with the Southwestern and Northern Indian Ocean most differentiated from each other. Effective migration rates were highest between the Southeastern Atlantic and the Southwestern Indian Ocean, followed by rates within the Southeastern Atlantic, and the lowest between the Southwestern and Northern Indian Ocean. At finer scales, very low gene flow was detected between the two neighbouring sub-regions in the Southeastern Atlantic, compared to high gene flow for whales within the Southwestern Indian Ocean. Our genetic results support the current management designations proposed by the International Whaling Commission of Breeding Stocks A, B, C, and X as four strongly structured populations. The population structure patterns found in this study are likely to have been influenced by a combination of long-term maternally directed fidelity of migratory destinations, along with other ecological and oceanographic features in the region. [ABSTRACT FROM AUTHOR]

Summary Seafood is one of the most traded food commodities in the world with demand steadily increasing [1]. There is, however, a rising concern over the vulnerability of seafood supply chains to species mislabelling and fraud [1,2]. DNA methods have been widely used to detect species mislabelling and a recent meta-analysis of 4500 seafood product tests from 51 publications found an average of 30 percent were not the species stated on the label or menu [3]. This high rate poses a serious threat to consumer trust, reputations of seafood businesses and the sustainability of fishery resources. Seafood certification schemes may help reduce this problem. Here, we use DNA barcoding [4] to validate the species identity of 1402 certified seafood products derived from 27 species across 18 countries and find that in over 99% of cases species labelling was correct. Barendse et al. use DNA barcoding to validate species composition of 1402 certified seafood products. Below 1 % were mislabelled suggesting fisheries certification reduces seafood fraud. [ABSTRACT FROM AUTHOR]

The article focuses on seafood as the most traded global community and on the need for solutions to prevent over-fishing. One of these solutions is aquaculture, the cultivation or farming of seafood, which is considered as the fastest growing food production sector in the world. The Southern African Sustainable Seafood Initiative (SASSI), a project of World Wildlife Fund (WWF)-South Africa, has conducted several seafood campaigns in order to increase the awareness of consumers about making more sustainable choices. INSET: SEX CHANGE IN FISH..