論文 - 詳細
| RRC ID | 70669 |
|---|---|
| 著者 | Céline C. Hanzen, Martyn C. Lucas, Olaf L.F. Weyl, Sean M. Marr, Gordon O’Brien, Colleen T. Downs |
| タイトル | Slippery customers for conservation: Distribution and decline of anguillid eels in South Africa |
| ジャーナル | Aquatic Conservation: Marine and Freshwater Ecosystems |
| Abstract |
1:Four anguillid eel species occur in the western Indian Ocean rivers of Africa: Anguilla bengalensis, Anguilla bicolor, Anguilla marmorata and Anguilla mossambica. These catadromous fishes face multiple stressors, including habitat alteration and deterioration, barriers to migration, pollution and the adverse impacts of alien species, but knowledge of eel species occurrence, abundance and ecology in Africa remains poor. 2:This study investigated the present and historical distribution of anguillid eels and the potential associated drivers of declines at the southern extremities of their ranges in South Africa. Data analysed included sampling conducted in KwaZulu–Natal and Eastern Cape between 2015 and 2020, and secondary data extracted from databases, museums and local management agencies. 3:The median extent of inland penetration increased as follows: 22 km for A. bicolor, 29 km for A. marmorata, 94 km for A. bengalensis and 293 km for A. mossambica. The median altitude followed a similar pattern. 4:Extent of occurrence analyses were carried out at the regional level in KwaZulu–Natal. The sampling data on present distribution (2015–2020), compared with historical data, suggests declines in the extents of occurrence of the four eel species in KwaZulu–Natal, ranging between 31 and 48% in the last 30 years and between 35 and 82% since the 1950s. 5:With increasing human threats in the region, especially from watercourse modification and water abstraction, further declines for these species are expected. Conservation measures recommended include the maintenance or restoration of the ecological connectivity of important rivers and the implementation of freshwater protected areas. Although eels are at present not widely exploited in South Africa, there is a need for fisheries regulations to manage sustainable commercial exploitation. |
| 公開日 | 2022-4-20 |
| DOI | 10.1002/aqc.3823 |
| IF | 2.572 |
| リソース情報 | |
| GBIF | Fish Specimens of the Yamagata Prefectural Museum Asia-Pacific Dataset Marine Biological Sample Database, JAMSTEC Fish specimens of Natural History Museum, Kishiwada City Vertebrate specimens of Kumamoto City Museum Fish monitoring data in Lake Kasumigaura Image Database of Fishes in the Kanagawa Prefectural Museum of Natural History Fish collection of the Kagoshima University Museum Actinopterygius Specimens of Akita Prefectural Museum Ibaraki Nature Museum, Fish collection Fish collection of the Museum of Nature and Human Activities, Hyogo Fish Collection of Yokosuka City Museum Fish Collection of Hokkaido University Fish Collection of Natural History Museum and Institute, Chiba Fish Specimens of Tokushima Prefectural Museum, Japan Fish Collection of Kanagawa Prefectural Museum of Natural History Fish Specimens of Graduate School of Bioresources Mie University Freshwater Fish specimens of Taga Town Museum, Shiga Pref., Japan Fish specimen database of Osaka Museum of Natural History Zoological specimens of Gifu Prefectural Museum Fish collection of National Museum of Nature and Science Gunma Museum of Natural History, Fish Specimen Freshwater Fish Specimens of Lake Biwa Museum Fish specimens of Takatsuki Nature Museum (Aquapia Akutagawa) Fish specimens of Okinawa Prefectural Museum & Art Museum Fish Collection of Coastal Branch of Natural History Museum and Institute, Chiba Fish specimens of Kaizuka City Museum of Natural History Pisces specimens of Tochigi Prefectural Museum Fish specimens of Toyama Science Museum |