Browsing by Subject "Entanglement"

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    Entanglement of Cape Fur Seals (Arctocephalus pusillus pusillus) in South Africa
    (2022) Henry, Maguiña Ramilo; Gridley, Tess; Reed, Cecile
    Global pollution is increasing, and marine mammals are commonly affected by the waste in the ocean. Endemic to the African continent, the pinniped species, Cape fur seal (Arctocephalus pusillus pusillus), are vulnerable to entanglement due to their curious nature and thick fur. Entanglement data were available from systematic photographic surveys of six colonies in South Africa (2019-2022) as well as opportunistic and citizen science records, photographs, aerial images and historical records from 1997 onwards. Overall, 314 cases of entangled seals were identified. As calculated from the systematic surveys, Baboon Point in Elands Bay (0.24% ± 0.78%, n = 7, with a 95% confidence interval) had the highest entanglement incidence. Seal Island in False Bay had the highest overall number of entanglements (50) and the highest mean number per survey (5.10 ± 0.46 number of entangled seals, n = 10), but this was also the largest colony assessed. Entanglement was observed the most in adults (61%, n = 189), with fishing materials being the primary cause of entanglements (40%, n = 59), specifically monofilament fishing lines (33%, n = 103). Although most entanglements were deemed ‘sight' (67%, n = 100), 28 cases (19%) were considered ‘severe,' likely impacting the health and welfare of affected individuals. Random Forest classification analysis identified the item of entangling material as an important predictor variable in terms of the severity level of the entanglement. The most common entangling material color was white (35%, n=82) followed by green (13%, n=30) and clear (7%, n=17) which may reflect the proportion of materials seals are exposed to, how they perceive them underwater, or their attraction to such colors. Aerial photographs showed higher efficiency in detecting entanglement cases than boat-based data where comparisons were possible. This is the first study to investigate entanglements of Cape fur seals in South Africa and highlights the need for correct disposal of waste, particularly that derived from the fishing industry, to mitigate its impacts on the welfare and conservation of marine fauna.
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    States, agency, and power on the ‘peripheries': exploring the archaeology of the later Iron Age societies in precolonial Mberengwa, CE 1300-1600s
    (2021) Nyamushosho, Robert Tendai; Chirikure, Shadreck
    In southern Africa, as elsewhere, the tendency of Iron Age (CE 200-1900) researchers has been to focus on the more prominent places on the landscape, especially those believed by pioneering archaeologists to have been centres of big states. Consequently, most research foci were accorded to Mapungubwe, Great Zimbabwe, Khami, Danamombe and many other places considered as centres (mizinda) of expansive territorial states. However, landscapes away from, and in-between these states and their centres are traditionally viewed as ‘peripheries' where resources that made them prosperous were extracted. The inhabitants of such ‘peripheries' are presented as if they possessed little or no agency. One such area is Mberengwa, a gold-rich area situated between the edges of Mapela, Mapungubwe, Great Zimbabwe, Danamombe, and Khami. This thesis explores the archaeology of Chumnungwa, a drystone-walled muzinda located in Mberengwa. Because of abundant gold, and a landscape optimal for cattle production and crop agriculture, Chumnungwa is often marginalised as a docile ‘periphery' of the more powerful and territorial states that surrounded it. Stratigraphic excavations were performed in different parts of the site to recover artefactual and chronological evidence. Indications are that the inhabitants of Chumnungwa exploited locally acquired resources such as gold, iron, and soapstone, but mixed these with resources from distant areas. Cumulatively, this evidence, when assessed in relation to chronology, suggests that Chumnungwa flourished more or less at the same time as Mapela, and the later phases of Mapungubwe, Great Zimbabwe, Khami, and Danamombe. As a powerful actor in Mberengwa, Chumnungwa also networked and was therefore entangled not only with local, but also with regional, and inter-regional politicoeconomic processes. This suggests it is only a historical invention that can marginalise some landscapes as ‘peripheral', especially in the absence of research, but once attention is directed to them, multiple layers of agency and entanglement emerge.