基于环境DNA的涠洲岛周围海域布氏鲸种群分布初探

Preliminary exploration of Balaenoptera edeni edeni population distribu-tion in surrounding waters of Weizhou Island based on environmental DNA

鲸类作为海洋生态系统中的顶级捕食者,是维持海洋生态平衡和生态稳定的关键物种。广西涠洲岛布氏鲸(Ba-laenoptera edeni edeni)是中国近海唯一稳定出现的须鲸种群,但其栖息地分布现状尚不明确。由于布氏鲸活动能力强、分布范围广,目视监测难以进行稳定跟踪调查。基于此,结合环境DNA(Environmental DNA,eDNA)技术,监测了不同时期(2022年4月和2023年1月)涠洲岛布氏鲸栖息地的分布现状。研究发现,4月在布氏鲸的热点分布海域(涠洲岛—斜阳岛之间)目视和eDNA均发现布氏鲸存在(n=3),同时在涠洲岛西南海域也发现布氏鲸存在(n=2),其中有1个站位仅eDNA检测到;1月在布氏鲸的热点分布海域目视和eDNA均发现布氏鲸存在(n=1),涠洲岛东部海域仅eDNA检测到布氏鲸存在(n=1)。结果表明,eDNA技术相比目视具有更高的灵敏度,可用于验证布氏鲸的分布,同时发现涠洲岛东部和西南部海域是布氏鲸的潜在热点分布海域。该研究验证了eDNA技术在涠洲岛布氏鲸分布监测上的可行性,进一步明确了涠洲岛布氏鲸栖息地的分布现状,为其种群的高效监测和科学保护提供了基线信息。

Cetaceans,as apex predators in marine ecosystems,play a key role in maintaining ecological balance and stability.The Eden's whale(Balaenoptera edeni edeni)in Weizhou Island is the only baleen whales population that consistently appears in the waters near China.However,their specific distribution around Weizhou Island remains unclear.Due to their extensive range and active behavior,conducting stable tracking surveys via visual means is challenging.Thus,through environmental DNA(eDNA)technology,we assessed the distribution status of Eden's whales habitats around Weizhou Island during different peri-ods(April 2022 and January 2023).The study reveals that in April,Eden's whales were visually observed and detected via eDNA in the hotspot distribution area(Between Weizhou Island and Xieyang Island)(n=3).They were also found in the southwest wa-ters of Weizhou Island(n=2),with one site solely identified via eDNA.In January,Eden's whales were visually observed through eDNA in the hotspot distribution area(n=1)and detected through eDNA in the eastern waters off Weizhou Island(n=1).The findings indicate that compared with visual observation,eDNA technology exhibited higher sensitivity and could be utilized to verify the distribution of Eden's whales.Furthermore,potential hotspot distribution areas for Eden's whales were identified in the eastern and southwestern waters off Weizhou Island.In conclusion,this research validates the feasibility of utilizing eDNA technology for monitoring the distribution of Eden's whales around Weizhou Island.Besides,it provides further clarification re-garding the distribution status of Eden's whales habitats around Weizhou Island,which supplies essential baseline information for the effective monitoring and scientific conservation of this population.