| Title | Raw image and operational data of grid/station number 90, Olifantsbos, 05 October 2024 |
|---|---|
| Authors |
Williamson, Ricardo Haupt, Tanya |
| Publisher | Department of Forestry, Fisheries and the Environment (2026) |
| Contributors |
Contact Person: Haupt, Tanya |
| Abstract | Benthic invertebrate communities, particularly sessile and semi-motile organisms like sponges, cnidarians and echinoderms, are effective for assessing long-term change, since they respond to factors such as marine pollution or climate change through measurable changes within populations over weeks to years. Exploratory research on these communities and their habitats has contributed substantially to increased understanding of benthic biota, and to the establishment of Marine Protected Areas (MPAs). However, very few repeat observations in the same areas are available to assess changes in benthic community structure and function over time. With long-term monitoring being a key DFFE mandate, such data availability is becoming increasingly important to assess the credibility of management strategies within MPAs. The key objective of this study was to establish long-term monitoring of the sessile and semi-motile benthic invertebrate communities occurring at various depths in a biodiversity rich area inside Table Mountain National Park MPA - Olifantsbos. The inshore area of Olifantsbos forms part of the Cape of Good Hope restricted zone and the survey was conducted using underwater imagery across four depth categories: 15 – 30 m, 31 – 50 m, 51 – 70 m and 71 – 90 m. Here we present the raw image data (JPEG) and metadata (csv. file) for grid/station number 90 (-34.2628613172; 18.3244363005) sampled on the 05 October 2024. |
| Methods | At each station, the drop camera was deployed from a winch off a small boat approximately +- 20 times (i.e. ~ 20 drops). The GoPro was set to record still images every second and at each drop (i.e. once the frame reaches the seafloor), the drop camera was left at the bottom for 60 seconds after which it would be lifted ~ five m off from the sea floor whilst circling within the general vicinity of the central co-ordinate (i.e. staying within the 250 x 250 m radius), and then dropped again. The drop camera was brought up onto the deck between stations and instances where the frame was snagged to check if it was still attached to the rope/winch. The data available for each station are the raw JPEG images taken by the GoPro from the time the drop camera frame reaches the surface of the water (start) till when it is brought up (end). The imagery data are accompanied by detailed metadata for each station in the form of a csv file capturing the date, station/grid number, co-ordinates, depth bin (15 – 30 m/ 31 – 50 m/51 – 70 m/71 – 90 m), the start (when the drop camera system enters the water) and end (when the drop camera system is brought back to the surface) times of the operation, the bottom time (i.e. each time the drop camera landed on the seafloor) and depth at each drop (recorded using the vessel’s echosounder), whether a temperature logger was attached to the drop camera frame, weather, team composition and any additional notes/observations. |
| Data | |
| Temporal extent | 05 Oct 2024 – 05 Oct 2024 |
| Geographic extent |
Olifantsbos, Table Mountain National Park Marine Protected Area (MPA), South Africa
Lat: -34.2628613172 |
| Keywords | ANIMALS/INVERTEBRATES , BIOLOGICAL CLASSIFICATION , biota , CNIDARIANS , Data status: completed , ECHINODERMS , EPSG:2048 , grid , Invertebrate Abundance and Distribution (emerging) , SOUTH ATLANTIC OCEAN , SPONGES , Taxonomic/phylogenetic diversity |
| Related resources |
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