Status of Napoleon wrasse in Laamu Atoll, Maldives, after three decades of protection

The Napoleon or humphead wrasse Cheilinus undulatus is a large, globally threatened coral reef fish. In recognition of suspected declines and considering its ecotourism importance, the Maldives was the first country to ban its export in 1995. The present study, a quarter-century after the ban, docum...

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Main Authors: P Roe, AS Hashim, V Evans, Y Sadovy de Mitcheson
Format: Article
Language:English
Published: Inter-Research 2022-11-01
Series:Endangered Species Research
Online Access:https://www.int-res.com/abstracts/esr/v49/p135-144/
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author P Roe
AS Hashim
V Evans
Y Sadovy de Mitcheson
author_facet P Roe
AS Hashim
V Evans
Y Sadovy de Mitcheson
author_sort P Roe
collection DOAJ
description The Napoleon or humphead wrasse Cheilinus undulatus is a large, globally threatened coral reef fish. In recognition of suspected declines and considering its ecotourism importance, the Maldives was the first country to ban its export in 1995. The present study, a quarter-century after the ban, documents the species around Laamu Atoll, southern Maldives, using dive guides and researchers to conduct surveys during commercial dive tourism trips. Data were collected on abundance, body size, and potential spawning sites in 4 habitat types: channels (reef passes to open ocean), inner reefs (reef slopes inside the atoll), outer reefs (reef slopes outside the atoll), and faros (isolated submerged reefs inside the atoll). Abundance was recorded in number of fish per hectare, and fish length was classified as <100 cm, ≥100 cm, or unknown size. Possible spawning aggregation sites were identified based on multiple occasions of temporarily increased fish density associated with large male presence. Mean densities ranged from 6.02 fish ha-1 in channels, 2.65 and 2.29 fish ha-1 in outer and inner reefs, respectively, and 0.73 fish ha-1 in faros. These densities are consistent with those found in unexploited areas in similar habitats elsewhere and indicate successful protection of the species on Laamu Atoll. The data highlight the significance of reef channel habitat for this species as important megafauna and the need for management to conserve both species and channel habitats. The value of non-specialist observers for conducting labour-intensive surveys on large, wide-ranging species is demonstrated.
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spelling doaj.art-5da8ef14f9344c3d827dff30bb65e5182023-02-06T14:57:06ZengInter-ResearchEndangered Species Research1863-54071613-47962022-11-014913514410.3354/esr01210Status of Napoleon wrasse in Laamu Atoll, Maldives, after three decades of protectionP Roe0AS Hashim1V Evans2Y Sadovy de Mitcheson3MUI by Six Senses Laamu, Olhuveli Island, Laamu Atoll, MaldivesBlue Marine Foundation, South Building, Somerset House, London WC2R 1LA, UKBlue Marine Foundation, South Building, Somerset House, London WC2R 1LA, UKScience and Conservation of Fish Aggregations (SCRFA) &amp; IUCN Grouper &amp; Wrasse Specialist Group, University of Hong Kong, Pok Fu Lam Road, Hong Kong SARThe Napoleon or humphead wrasse Cheilinus undulatus is a large, globally threatened coral reef fish. In recognition of suspected declines and considering its ecotourism importance, the Maldives was the first country to ban its export in 1995. The present study, a quarter-century after the ban, documents the species around Laamu Atoll, southern Maldives, using dive guides and researchers to conduct surveys during commercial dive tourism trips. Data were collected on abundance, body size, and potential spawning sites in 4 habitat types: channels (reef passes to open ocean), inner reefs (reef slopes inside the atoll), outer reefs (reef slopes outside the atoll), and faros (isolated submerged reefs inside the atoll). Abundance was recorded in number of fish per hectare, and fish length was classified as <100 cm, ≥100 cm, or unknown size. Possible spawning aggregation sites were identified based on multiple occasions of temporarily increased fish density associated with large male presence. Mean densities ranged from 6.02 fish ha-1 in channels, 2.65 and 2.29 fish ha-1 in outer and inner reefs, respectively, and 0.73 fish ha-1 in faros. These densities are consistent with those found in unexploited areas in similar habitats elsewhere and indicate successful protection of the species on Laamu Atoll. The data highlight the significance of reef channel habitat for this species as important megafauna and the need for management to conserve both species and channel habitats. The value of non-specialist observers for conducting labour-intensive surveys on large, wide-ranging species is demonstrated.https://www.int-res.com/abstracts/esr/v49/p135-144/
spellingShingle P Roe
AS Hashim
V Evans
Y Sadovy de Mitcheson
Status of Napoleon wrasse in Laamu Atoll, Maldives, after three decades of protection
Endangered Species Research
title Status of Napoleon wrasse in Laamu Atoll, Maldives, after three decades of protection
title_full Status of Napoleon wrasse in Laamu Atoll, Maldives, after three decades of protection
title_fullStr Status of Napoleon wrasse in Laamu Atoll, Maldives, after three decades of protection
title_full_unstemmed Status of Napoleon wrasse in Laamu Atoll, Maldives, after three decades of protection
title_short Status of Napoleon wrasse in Laamu Atoll, Maldives, after three decades of protection
title_sort status of napoleon wrasse in laamu atoll maldives after three decades of protection
url https://www.int-res.com/abstracts/esr/v49/p135-144/
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