2 - Phenoxyethanol as anaesthetic in removing and relocating 102 species of fishes representing 30 families from Sea World to uShaka Marine World , South Africa

The South African Association for Marine Biological Research, incorporating Sea World, Oceanographic Research Institute and the Dolphinarium relocated from their old premises of 46 years on Durban’s beach front in March and April 2004 to the new Point Development’s marine theme park, uShaka Marine World in Durban, South Africa. Netting of fishes from the large exhibits could cause physical damage to struggling fishes, increasing the risk of opportunistic secondary bacterial infections (Inoue, dos Santos Neto & Morales 2004) which could not be treated in time for the opening of uShaka Marine World on 30 April 2004. An ideal method to facilitate the removal of fishes from exhibits would be the use of a general anaesthetic. Characteristics of a suitable anaesthetic for this purpose would include ease of administration and stability, rapid recovery of anaesthetised fishes once re-introduced into untreated water and the dependency of anaesthetic duration upon concentration (Dunn & Koester 1985). “2-Phenoxyeth a nol” (MercK Laboratories, Johannesburg) was selected to facilitate the removal of fishes from the two main aquarium exhibits, the open ocean exhibit, housing the highest diversity of fishes (Table 1), and the shark tank housing two large adult Zambezi sharks, Carcharhinus leucas Valenciennes, 1839, eight adult Spotted ragged-tooth sharks, Carcharias taurus Rafinesque, 1810, and several sympatric teleost species (Table 2). 2-Phenoxyethanol is relatively inexpensive and remains viable in long-term exposure (Kaiser & Vine 1998) and is also available in bulk in South Africa. Deacon, White & Hecht (1997) recommend 2-Phenoxyethanol as a highly suitable anaesthetic for repeatedly exposed fishes. 2-Phenoxyethanol also showed a more notable sedation than MS-222 in an experiment on Gilthead sea bream, Sparus aurata (Molinero & Gonzalez 1995) and is considered a desirable anaesthetic for the transportation of fishes by Yanar & Kumlu (2001).