2025-12-10 テキサスA&M大学
Fossils of Salwasiren qatarensis, a newly described 21-million-year-old ancient sea cow species found in Al Maszhabiya [AL mahz-HA-bee-yah], a fossil site in southwestern Qatar.Credit: ARC.2023.23.008, Qatar Museums, Doha, State of Qatar. Photo by James Di Loreto, Smithsonian.
＜関連情報＞
- https://stories.tamu.edu/news/2025/12/10/new-discoveries-reveal-arabian-gulf-hosts-both-ancient-fossil-bed-containing-newly-identified-sea-cow-species-and-worlds-largest-living-dugong-herd/
- https://peerj.com/articles/20030/
- https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2025.1620194/full
カタールで中新世初期のカイギュウが大量に発見されたことは、東テチス海域の海草生態系エンジニアの繰り返し進化を示している High abundance of Early Miocene sea cows from Qatar shows repeated evolution of seagrass ecosystem engineers in Eastern Tethys
Nicholas D. Pyenson, Ferhan Sakal, Jacques LeBlanc, Jon Blundell, Katherine D. Klim, Christopher D. Marshall, Jorge Velez-Juarbe, Katherine Wolfe, Faisal Al-Naimi
PeerJ Published:December 10, 2025
DOI:https://doi.org/10.7717/peerj.20030
Abstract
Coastal ecosystems that include seagrasses are potential carbon sinks that require strategic conservation of top trophic consumers, such as dugongs, to maintain their function. It is unclear, however, how long seagrass ecosystems have persisted in geologic time because their fossil record is poor, although the record of their associated vertebrate consumers offers useful proxies. Here we describe an area of dense Early Miocene dugongid remains from Qatar. We documented over 172 sites in <1 km2 from one stratigraphic level, including material representing a new species of fossil dugongine dugongid. This taxon is unrelated to coeval Early Miocene dugongids from India and the Eastern Tethys and it is distantly related to extant dugongs, which occupy seagrass habitats of the Persian or Arabian Gulf (hereafter ‘Gulf’) today. The monodominant assemblage in this area likely reflects a single fossil dugongid taxon and matches the ecological diversity and geospatial distribution of modern-day live-dead assemblages in the Gulf. This fossil site from Qatar shows that the Gulf has repeatedly evolved sea cow communities with different taxa over the past 20 million years and coincides with an Early Miocene marine biodiversity hotspot in Arabia, prior to its eastward shift to the Indo-Australian Archipelago where dugongs continue to thrive today.
無人航空機を用いたアラビア湾中部におけるジュゴン（ Dugong dugon ）の最大の群れの検出 Detection of the largest herd of dugongs (Dugong dugon) in the Central Arabian Gulf using unmanned aerial vehicles
Danah I. Alagha,Yousria Soliman,Christopher Marshall,Mehsin Alansi
Frontiers in Marine Science Published:14 October 2025
DOI:https://doi.org/10.3389/fmars.2025.1620194
The dugongs (Dugong dugon), one of the few marine herbivorous mammals, are classified as vulnerable species by the IUCN, and their population monitoring is critical for informed conservation efforts. Although limited research has confirmed that the Arabian Gulf, in the northwest Qatar, hosts the world’s largest dugong aggregations, studies on their exact numbers remain limited. We conducted boat-based drone surveys in 2019–2020 to estimate the magnitude of the sizable aggregations of dugongs in northwest Qatar. We conducted 14 surveys during 2019–2020 by employing Unmanned Aerial Vehicle (Drone) and photographic analysis techniques. Potential biotic and abiotic factors driving this gathering of dugongs were explored. Maximum dugong observed counts were 1108 in 2019 and 1209 in 2020. The percentage of cow-calf pairs in the total group was 5.8% in 2019, and 10.2% in 2020. Upon applying a detection probability of 0.96 and an availability probability range of 0.8-0.98, the adjusted estimated counts of dugongs ranged from 994 to 1574, with an overall estimated mean of 1248 ± 122 dugongs. We suggest that the significant dugong aggregations in the area during winter are primarily due to foraging on the abundant seagrass in this area, the relatively warmer waters (>18 °C) and the sheltering effect topography from turbulent waters caused by shamal winds during the winter months. This information is crucial for wildlife managers, stakeholders, and government agencies to facilitate informed decision-making concerning the management and protection of dugongs.
