Dear MARMAM-ers
On behalf of the team I am pleased to announce the
publication of our new research paper in Ecology and Evolution.
The paper can be accsessed by the link: https://www.zoores.ac.cn/en/article/doi/10.24272/j.issn.2095-8137.2022.504
Peng-Xiang Duan, Zhi-Tao Wang, Tomonari Akamatsu,
Nick Tregenza, Guang-Yu Li, Ke-Xiong Wang, Ding Wang. Anthropogenic activity,
hydrological regime, and light level jointly influence temporal patterns in
biosonar activity of the Yangtze finless porpoise at the junction of the
Yangtze River and Poyang Lake, China. Zoological Research, 2023,
44(5): 919-931. doi: 10.24272/j.issn.2095-8137.2022.504
Abstract
Under increasing
anthropogenic pressure, species with a previously contiguous distribution
across their ranges have been reduced to small fragmented populations. The
critically endangered Yangtze finless porpoise (Neophocaena asiaeorientalis
asiaeorientalis), once commonly observed in the Yangtze River-Poyang Lake
junction, is now rarely seen in the river-lake corridor. In this study, static
passive acoustic monitoring techniques were used to detect the biosonar
activities of the Yangtze finless porpoise in this unique corridor. Generalized
linear models were used to examine the correlation between these activities and
anthropogenic impacts from the COVID-19 pandemic lockdown and boat navigation,
as well as environmental variables, including hydrological conditions and light
levels. Over approximately three consecutive years of monitoring (2020–2022),
porpoise biosonar was detected during 93% of logged days, indicating the key
role of the corridor for finless porpoise conservation. In addition, porpoise
clicks were recorded in 3.80% of minutes, while feeding correlated buzzes were
detected in 1.23% of minutes, suggesting the potential existence of localized,
small-scale migration. Furthermore, both anthropogenic and environmental
variables were significantly correlated with the diel, lunar, monthly,
seasonal, and annual variations in porpoise biosonar activities. During the
pandemic lockdown period, porpoise sonar detection showed a significant
increase. Furthermore, a significant negative correlation was identified
between the detection of porpoise click trains and buzzes and boat traffic
intensity. In addition to water level and flux, daylight and moonlight
exhibited significant correlations with porpoise biosonar activities, with
markedly higher detections at night and quarter moon periods. Ensuring the
spatiotemporal reduction of anthropogenic activities, implementing vessel speed
restrictions (e.g., during porpoise migration and feeding), and maintaining
local natural hydrological regimes are critical factors for sustaining porpoise
population viability.
On the belhalf of the team
Zhitao Wang
--
Zhitao Wang Associate Professor
School of
Marine Science, Ningbo University
Ningbo,
Zhejiang 315832, China
https://orcid.org/0000-0002-5734-7385
https://www.researchgate.net/profile/Zhitao-Wang/research
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