Assessment Aerial flight Methods

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3.3 Assessment

The earliest assessment of the coral bleaching event was initially through a survey conducted by the Reef Check program at the Fijian Resort at Cuvu Reef February 25, 2000. Subsequently, an aerial survey was conducted of the bleaching, particularly with respect to the northern part of Fiji. It was of interest to see if this differential influence was manifest in the degree of coral bleaching. Subsequently, field visits were conducted to determine the in situ effect of the bleaching. These occurred on the Great Sea Reef north of Labasa, Vanua Levu I. On the south side of the island, surveys were conducted by some members of the Fiji Dive Operators Association see appendix 1 and at the Jean-Michel Cousteau resort. Similar surveys were conducted near Suva, particularly at Rat Tail passage. The Fiji Dive Operators were interviewed on the extent of the bleaching in their area. Summary accounts were made of other surveys conducted throughout Fiji at various stages during the event.

3.4 Aerial flight

An aerial flight was conducted at 11AM on April 21, 2000 to assess the extent of the bleaching from the Suva area to the Cakaulevu Reef, the extensive barrier reef to the north of the main Fiji islands. The NOAA hotspot charts indicated that the area of the highest temperature elevation was the southeast corner of Viti Levu extending both to the southeast and north to southern Vanua Levu. On the northern side of Vanua Levu the temperatures were very reduced, approaching normal. The objective of the flight was to assess whether the bleaching was less. This proved to be the case with severe bleaching indicated in the Suva area and Bau Waters but very reduced on the northern barrier reef. With clear weather conditions and a low tide, the extent of the bleaching was easily observable. It was pronounced on the fore-reef areas of the barrier reefs which extending from Rat Tail Passage to Naisali Pt, on the southeast corner. Similar observations were made in flying over Bau Waters and heading along the barrier reefs adjacent Ovalau I. It was very clear upon crossing Vanua Levu, that bleaching was far less with little bleaching being discerned on the Cakaulevu barrier reef. Figure 5. Aerial photos of the contrasting areas of coral bleaching. Nukubuco Reef above exhibits substantial bleaching as is evident on the margins of the spur and groove system. By contrast, the area, north of Vanua Levu had only minor bleaching below. Figure not available in electronic format 12 Figure 6. Aerial flight path conducted to determine the degree of bleaching from southern Viti Levu to the north of Vanua Levu, Fiji Figure not available in electronic format 13 The suvey of the coral bleaching event in Fiji was based on a sample of three localities which were representative of three regions of increasing latitude. The northern site is where the coral bleaching was minimal. The mid-region was southern Vanua Levu. The third area was southern Viti Levu. These latter areas shared habitats that represented examples of severe, moderate and minimal influence. With in the later two localities contrasting habitats of reef front, inshore reef and reef at depth.

4.1 Northern Vanua Levu Survey