https://vital.seals.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://vital.seals.ac.za/vital/access/manager/Repository/vital:20671 Wed 26 Oct 2022 16:15:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:2874 Wed 12 May 2021 23:39:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:10552 Wed 12 May 2021 23:28:23 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:1287 Wed 12 May 2021 23:21:53 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:20336 Wed 12 May 2021 22:28:50 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:10725 Wed 12 May 2021 21:04:51 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:30692 Wed 12 May 2021 21:04:22 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5383 3m) coastal shark species, widely distributed in tropical and sub-tropical Indo-Pacific waters. Despite its large size and wide distribution, very little is known about its movement behaviour throughout ontogeny. The primary aim of this thesis was to gain an understanding of the movements of sub-adult N. acutidens, in and around the St. Joseph Atoll, Republic of Seychelles, to facilitate the effective conservation of this vulnerable species. A total of 22 sharks (139 – 202 cm TL) were equipped with coded acoustic transmitters and passively monitored using moored acoustic receivers for a period of 20 month from March 2009 to October 2010. The use of passive acoustic telemetry arrays to study behavioural ecology has increased in popularity in recent years and been successfully applied to study a host of teleost and elasmobranch species in a diversity of habitats, ranging from sheltered estuaries to the offshore pelagic environment. However, the practicalities of designing an effective network of receivers to optimally monitor animal movements can be challenging. In this study the receiver array was optimised through a series of incremental steps to achieve an efficient design that allowed for the specific objectives to be addressed. The specific objectives of this study were to i) gain an understanding of the long term space use patterns and site fidelity of sub-adult N. acutidens within degree of use of the St. Joseph Atoll lagoon and surrounding habitats, and ii) investigate their short term behavioural patterns in response to natural rhythmic cycles. The important role the atoll plays in the sub-adult stage of this species was demonstrated by the very low numbers of detections outside the atoll compared to the very large numbers of detections inside the atoll. Over the course of a year the tagged sharks showed a high degree of site fidelity to the atoll, with 79 – 100% of the individuals detected during each month and 50% being detected on a near daily basis. This result provides testimony of the nursery role of the atoll and importance of these habitats in the early life history for this species. Individual area use was generally found to be restricted to the eastern part of the atoll incorporating a portion of the central deep lagoon and a nearby adjacent area of the sand flats. The movements of sub-adult N. acutidens on and off of the shallow flats surrounding the central lagoon (likely for foraging) were found to be strongly influenced by the tidal height and the diel cycle. Tagged sharks were found to utilise the flats more regularly when the tidal height was greater than 90 cm and particularly more so during the night and early morning than during daylight times. The combined results of this study expose the vulnerability of this species to rapid local depletion. Similarly, the effectiveness of spatial management measures, such as no-take marine protected areas is highlighted as an efficient tool for the future conservation of this species. In the St. Joseph Atoll in particular, the use of a multi-levelled protection approach, where the eastern portion on the atoll is completely restricted while the remaining area is utilized for non-consumptive tourism activities, could be highly effective. Future research should investigate changes in area use throughout the ontogeny of this species as well improve the understanding of the breeding site fidelity and population size of reproductive females using the St. Joseph Atoll.]]> Wed 12 May 2021 20:28:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:20918 Wed 12 May 2021 20:23:08 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:2267 Wed 12 May 2021 20:10:05 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:34368 0.05) among the varieties. The highest fresh biomass yields were observed in PAN 888 variety was 13400 kg/ha, King had 12600 kg/ha and PAN 868 had 12600 kg/ha. The dry matter yield observed in PAN 888 was 4300.00 DM kg/ha, PAN 868 had 3633.33 DM kg/ha and King yielded 3533.33 DM kg/ha. The different sorghum varieties showed a significant (P<0.01) difference in some chemical composition parameters namely DM, NDIN and NSC. The different sorghum varieties had significant difference (P<0.01) in the silage fermentation parameters of pH, starch and lactic acid. The sorghum silage varieties were significantly (P<0.01) different in the starch fermentation with values of 0.001percent. The sorghum silage varieties were significant different for fermentation of lactic acid with values ranging from 1.99 to 2.62percent. However, PAN 868 and PAN 888 were not different from each other. Similarly, all varieties were different (P<0.05) in the pH with values ranging from 4.16 to 4.53. There were no significant (P>0.05) differences in CP, Fat, NDF, ADF, Hemicellulose, Ash, and ADIN content of the silages. The mineral composition (macro and micro) of the silage were not significantly (P>0.05) different among the varieties. In conclusion, the dry matter production and nutrient content of the three forage sorghum varieties were not significantly different. The silage fermentation quality showed significant (P<0.05) differences among the three sorghum varieties. Therefore, according to the results of this study PAN 888 is the recommended variety to grow in the semi-arid region of the Eastern Cape.]]> Wed 12 May 2021 20:09:45 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:4463 Wed 12 May 2021 20:04:16 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:39710 Wed 12 May 2021 19:48:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:39271 Wed 12 May 2021 19:20:24 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:26576 Wed 12 May 2021 18:38:11 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:21203 Wed 12 May 2021 18:38:06 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:4152 Wed 12 May 2021 18:36:22 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:39720 Wed 12 May 2021 18:14:05 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:27618 Wed 12 May 2021 16:45:36 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:1748 Wed 12 May 2021 16:26:21 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:20684 Wed 12 May 2021 16:24:18 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:1131 Wed 12 May 2021 16:15:00 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:28345 Wed 12 May 2021 15:48:46 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:42731 Wed 12 May 2021 14:59:46 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:42228 Wed 12 May 2021 14:55:32 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:40704 Wed 12 May 2021 14:29:14 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:40581 Wed 12 May 2021 14:25:10 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3346 Thu 13 May 2021 06:56:16 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:10069 Thu 13 May 2021 06:49:41 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3506 Thu 13 May 2021 06:44:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:38962 Thu 13 May 2021 06:22:36 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:800 Thu 13 May 2021 06:01:23 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:8515 Thu 13 May 2021 05:27:26 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:8420 Thu 13 May 2021 04:57:37 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5426 Thu 13 May 2021 04:17:52 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:10662 Thu 13 May 2021 03:16:19 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:30783 Thu 13 May 2021 03:05:48 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:1555 Thu 13 May 2021 02:58:57 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:21222 Thu 13 May 2021 02:48:59 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:3500 Thu 13 May 2021 02:37:51 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:20483 Thu 13 May 2021 02:25:33 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5972 Thu 13 May 2021 02:06:26 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:20976 Thu 13 May 2021 01:37:18 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:38990 Thu 13 May 2021 01:22:13 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:26907 Thu 13 May 2021 01:16:26 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:5394 Thu 13 May 2021 00:52:23 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:4178 Thu 13 May 2021 00:09:24 SAST ]]> https://vital.seals.ac.za/vital/access/manager/Repository/vital:21338 Thu 06 Jul 2023 11:57:39 SAST ]]>