The effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems
Establishing the associations between fish and their habitats can aid in the monitoring of fish stocks and the design of effective marine protected areas (MPAs). Baited remote underwater stereo-video systems (stereo-BRUVs) are now commonly used to asses fish populations. The habitats seen in the vid...
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ftsealsdc:vital:29249 2024-09-09T20:13:25+00:00 The effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems Schmidt, Nicholas C 2019 109 pages pdf http://hdl.handle.net/10962/68380 http://vital.seals.ac.za:8080/vital/access/manager/Repository/vital:29249 English eng Rhodes University Faculty of Science, Ichthyology and Fisheries Science http://hdl.handle.net/10962/68380 vital:29249 http://vital.seals.ac.za:8080/vital/access/manager/Repository/vital:29249 Schmidt, Nicholas C Baited remote underwater stereo-video systems (stereo-BRUVs) Remote underwater stereo-video systems Underwater videography in wildlife monitoring -- South Africa -- Tsitsikamma Fish stock assessment -- South Africa -- Tsitsikamma Fish populations -- Monitoring -- South Africa -- Tsitsikamma Fishes -- Habitat -- South Africa -- Tsitsikamma text Thesis Masters MSc 2019 ftsealsdc 2024-07-29T23:41:47Z Establishing the associations between fish and their habitats can aid in the monitoring of fish stocks and the design of effective marine protected areas (MPAs). Baited remote underwater stereo-video systems (stereo-BRUVs) are now commonly used to asses fish populations. The habitats seen in the video footage of stereo-BRUVs can be used to link fish fauna to preferred habitat types. However, the application of bait potentially attracts fish from surrounding habitats, and might result in a biased understanding of fish–habitat associations. A field study was conducted in the Tsitsikamma National Park MPA to determine the effect of bait on fine-scale fish–habitat associations, using remote photographic and video methods. The study was conducted over the summer season of 2015 and 2016. Data were collected within a 1x1 km shallow (9–44 m) reef complex. Within the sampling area, 944 photo-quadrats of the macrobenthos were taken 30 m apart by means of a drop camera. By separating the macrobenthos into broad taxonomic groups, five habitat types were identified, namely Shallow Sand, Shallow Reef, Deep Reef, Deep Sand and Patch Reef. The results show that even on a fine scale, depth is an important predictor of macrobenthic distribution and assemblage structure. Baited (stereo-BRUVs) and unbaited (stereo-RUVs) surveys were then conducted to sample the fish community in the same area during the period under study. Higher abundances of fish were observed in reef than in sandy habitats, and bait was seen to have a positive effect on species richness and fish abundance. When comparing habitats, fish abundance and composition on reef habitats were significantly different from sand habitats. This was observed in both the stereo-RUVs and stereo-BRUVs methods. High counts of roman (Chrysoblephus laticeps), fransmadam (Boopsoidea inornata) and steentjie (Spondyliosoma emarginatum) in reef habitats were contrasted by high counts of white sea catfish (Galeichthys feliceps), evil-eye puffer (Amblyrhynchotes honckenii) and lesser ... Master Thesis White Sea SEALS Digital Commons (South East Academic Libraries System, South Africa) White Sea |
institution |
Open Polar |
collection |
SEALS Digital Commons (South East Academic Libraries System, South Africa) |
op_collection_id |
ftsealsdc |
language |
English |
topic |
Baited remote underwater stereo-video systems (stereo-BRUVs) Remote underwater stereo-video systems Underwater videography in wildlife monitoring -- South Africa -- Tsitsikamma Fish stock assessment -- South Africa -- Tsitsikamma Fish populations -- Monitoring -- South Africa -- Tsitsikamma Fishes -- Habitat -- South Africa -- Tsitsikamma |
spellingShingle |
Baited remote underwater stereo-video systems (stereo-BRUVs) Remote underwater stereo-video systems Underwater videography in wildlife monitoring -- South Africa -- Tsitsikamma Fish stock assessment -- South Africa -- Tsitsikamma Fish populations -- Monitoring -- South Africa -- Tsitsikamma Fishes -- Habitat -- South Africa -- Tsitsikamma Schmidt, Nicholas C The effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems |
topic_facet |
Baited remote underwater stereo-video systems (stereo-BRUVs) Remote underwater stereo-video systems Underwater videography in wildlife monitoring -- South Africa -- Tsitsikamma Fish stock assessment -- South Africa -- Tsitsikamma Fish populations -- Monitoring -- South Africa -- Tsitsikamma Fishes -- Habitat -- South Africa -- Tsitsikamma |
description |
Establishing the associations between fish and their habitats can aid in the monitoring of fish stocks and the design of effective marine protected areas (MPAs). Baited remote underwater stereo-video systems (stereo-BRUVs) are now commonly used to asses fish populations. The habitats seen in the video footage of stereo-BRUVs can be used to link fish fauna to preferred habitat types. However, the application of bait potentially attracts fish from surrounding habitats, and might result in a biased understanding of fish–habitat associations. A field study was conducted in the Tsitsikamma National Park MPA to determine the effect of bait on fine-scale fish–habitat associations, using remote photographic and video methods. The study was conducted over the summer season of 2015 and 2016. Data were collected within a 1x1 km shallow (9–44 m) reef complex. Within the sampling area, 944 photo-quadrats of the macrobenthos were taken 30 m apart by means of a drop camera. By separating the macrobenthos into broad taxonomic groups, five habitat types were identified, namely Shallow Sand, Shallow Reef, Deep Reef, Deep Sand and Patch Reef. The results show that even on a fine scale, depth is an important predictor of macrobenthic distribution and assemblage structure. Baited (stereo-BRUVs) and unbaited (stereo-RUVs) surveys were then conducted to sample the fish community in the same area during the period under study. Higher abundances of fish were observed in reef than in sandy habitats, and bait was seen to have a positive effect on species richness and fish abundance. When comparing habitats, fish abundance and composition on reef habitats were significantly different from sand habitats. This was observed in both the stereo-RUVs and stereo-BRUVs methods. High counts of roman (Chrysoblephus laticeps), fransmadam (Boopsoidea inornata) and steentjie (Spondyliosoma emarginatum) in reef habitats were contrasted by high counts of white sea catfish (Galeichthys feliceps), evil-eye puffer (Amblyrhynchotes honckenii) and lesser ... |
format |
Master Thesis |
author |
Schmidt, Nicholas C |
author_facet |
Schmidt, Nicholas C |
author_sort |
Schmidt, Nicholas C |
title |
The effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems |
title_short |
The effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems |
title_full |
The effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems |
title_fullStr |
The effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems |
title_full_unstemmed |
The effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems |
title_sort |
effect of bait on fine-scale habitat associations of reef fish investigated with remote underwater video systems |
publisher |
Rhodes University |
publishDate |
2019 |
url |
http://hdl.handle.net/10962/68380 http://vital.seals.ac.za:8080/vital/access/manager/Repository/vital:29249 |
geographic |
White Sea |
geographic_facet |
White Sea |
genre |
White Sea |
genre_facet |
White Sea |
op_relation |
http://hdl.handle.net/10962/68380 vital:29249 http://vital.seals.ac.za:8080/vital/access/manager/Repository/vital:29249 |
op_rights |
Schmidt, Nicholas C |
_version_ |
1809815112575352832 |