| Shark Reef Fish List |
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Shark Reef Marine Reserve (SRMR) 2009 Fish Count Analysis: Thirty two scuba dives were made in the SRMR during February 2009 by Earle and Whitton, the same observers using the same methodology as in 2008. An additional __ species were added to the list of species from SRMR, which brought the total fish species count in SRMR to ___ species. The high number of additional species found in 2009 is further indication of the improving health of the reef since 2004, and also that the point of diminishing returns in discovering additional species has not yet been reached. On the penultimate diving day in 2009, when a dive was made on the previously unsurveyed boundary of the East Side of the SRMR, six additional species were added to the list. Four species were added on the last day when a dive was made to 40 meters. Future observations at depths over 35 meters and at the east and west boundaries of the SRMR would likely add many more species to the SRMR fishes list. Of course chemical collecting would also add many cryptic species. The East Side in particular looks promising because of the presence of several microhabitats not seen elsewhere in SRMR, such as a shallow acropora coral dominated shelf at 6 meters and extensive sandy areas observed but not explored at around 25 meters and deeper. Some small fishes were collected with quinaldine in 2009 for identification purposes. Earle and Whitton made one dive at a site (called ET?) just across the Beqa Channel from SRMR. Species were observed there that have not yet been seen at SRMR, but which may be expected to turn up at SRMR. Examples of such species in just the family Serranidae would include: Cephalopholis miniata, C. sexmaculata, Epinephelus tauvina, Gracila albomarginata, Pseudanthias bicolor, P. cooperi, and a Luzonichthys species (likely L. waitei). Clearly there is more work to be done at SRMR. One of the more interesting observations in 2009 was a Tomiyamichthys species of shrimp goby that was photographed in the sand patch at 33 meters where the equally surprising discovery of Stonogobiops yasha was made in 2008. This is a range extension for the genus, and may represent an undescribed species.  2006 paper by Juerg Brunnschweiler and John Earle which lists 267 species seen at SRMR during 7 scuba dives from 9/28/2004 to 10/01/2004 2008 Fish Count ANALYSIS: The total fish species count for SRMR in 2008 was 381, which is 114 more species than were seen in 2004. Several factors could account for this higher species count: In 2004 one observer recorded species during 7 dives at SRMR. In 2008 two observers recorded species during 20 dives each, for a total of 40 species survey dives. The additional observation time was probably significant in adding species because many species listed were seen only once or twice during 2008. These could represent transient or cryptic species, or species present in low numbers at SRMR. Fish survey methodology was more efficient in 2008. In 2004 the observer scribbled species names on a slate, which necessitated much “head down” time. In 2008 the observers either quickly checked off entries on a prepared underwater fish list or recorded species by video camera. The observer in 2004 was considerably distracted from fish counting by silvertip sharks, which occasionally bumped him and required warding off. This did not happen in 2008, possibly because the shark feed protocol seemed more disciplined and the sharks better “trained.” Several habitats that were not visited in 2004 were surveyed in 2008, such as the channel at the west boundary of SRMR and an area of sand and patch reefs at 33 meters depth. These habitats had many species not seen elsewhere in SRMR. However other micro-habitats remain yet unsurveyed. The shallow reef habitat appeared healthier in 2008 than in 2004. Coral growth was prolific in areas previously barren. Easily observed species associated with coral, including the coral-feeding butterflyfishes Chaetodon trifascialis, C. ornatissimus, C. melannotus and C. lineolatus, were recorded in 2008, but not observed in 2004. A prolific and healthy reef supports more species. The health of the SRMR reef may be the result of four years of good stewardship. While there is no comprehensive fish species list published for Fiji, the Checklist of the Shore and Epipelagic Fishes of Tonga by Randall et al would be expected to have similar fauna. This was generally true. However, the observers did find some surprises at SRMR in 2008. There were several significant range extensions, such as Chaetodon oxycephalus, the spot-nape butterflyfish, previously recorded from the Maldives to the Solomon Islands. Amblyeleotris yanoi, the flagtail shrimpgoby, previously recorded from the Ryukyu Islands and Bali to Flores in Indonesia, was also recorded at SRMR. This species and another shrimpgoby similar to Amblyeleotris elipse (previously recorded from Samoa), along with several other SRMR species, have visible differences from the nominal species to which we have tentatively assigned them (as noted in text on the species list). Such SRMR species could be undescribed scientifically. Effort should be made in the future to collect specimens for analysis. In the observers’ experience in making area fish lists, there eventually comes a point when few additional species are found, regardless of how many more dives are made or how methodical the search. The fish survey of SRMR is not yet at the point of diminishing returns. On their last dive the observers recorded 5 additional species. Many micro-habitats remain poorly surveyed, or not surveyed at all. Moreover, there was no collecting with an ichthyocide such as rotenone, which would be expected to add many more cryptic species to the fish list. Obviously further research is required at SRMR to fully assess the faunal diversity. Considering the constraints of observer time and survey methods utilized, the 381 fish species recorded during a brief window of time in a limited area is a impressive number and indicative of a rich and diverse fish fauna. The shark population at SRMR would appear to be supported by a solid foundation at lower trophic levels.  2004 Fish Count The 267 species of fish listed here were personally observed by John Earle (Research Associate in Zoology, Bishop Museum, Honolulu, Hawai'i) during 7 scuba dives at Shark Reef, Fiji between September 28 and October1, 2004. Depth ranged from 100' (30 m) at the lower shark feeding station to the 10' (3 m) decompression stop.
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