Animal movement is crucial for ensuring species survival and maintaining ecosystem processes. Marine organisms rely on straits for migration, however, the barrier effects of straits on wildlife movement have not been estimated. The Qiongzhou Strait, a vital habitat for various marine species, is also one of the busiest and most densely trafficked maritime areas in southern China. This study assessed the potential role of underwater noise as a contributing factor to the barrier effect of straits on cetaceans by measuring underwater noise levels at three sites in the Qiongzhou Strait across four trials (each 12–21 days long) in 2018 and 2019 (two per year). The root-mean-square sound pressure level (SPLrms) and the cumulative weighted sound exposure level (CWSEL) were calculated and evaluated against established regulatory acoustic thresholds: the possible effective quiet threshold (EQT), the thresholds for the onset of temporary threshold shift (TTS), and those for auditory injury (AUD INJ). The results suggested that noise in the Qiongzhou Strait has a greater impact on very high-frequency (VHF) and low-frequency (LF) cetaceans than on high-frequency (HF) cetaceans. Specifically, the average SPLrms was lower than the EQT for HF cetaceans but exceeded that for VHF cetaceans in 75 % of trials. Meanwhile, the mean CWSEL surpassed the TTS-onset thresholds for VHF and LF cetaceans in 50 % and 75 % of trials, respectively. In contrast, the mean CWSEL for HF cetaceans remained below the TTS-onset threshold across all trials. Nevertheless, for all three cetacean groups, the CWSEL exceeded the respective EQT while remaining below the respective AUD INJ thresholds. The machine learning TreeNet algorithm revealed pronounced spatiotemporal variability in both unweighted and weighted sound exposure level. The findings of this study provide valuable insights into the potential mechanisms by which underwater noise from busy navigation contributes to the barrier effect of straits on wildlife movement. Additionally, they offer important implications for managing underwater noise and conserving cetaceans in strait regions worldwide.

Conservation on cetaceans are highly concerned worldwide in recent decades. Cetaceans are known to produce various sounds and mainly rely on sounds for communication, expression of internal state, mating, foraging, and even navigation. Underwater sound is one of the essential ocean variables, which is especially considered in terms of conservation on cetaceans. Therefore, conservation-related bioacoustics researches including but not limited to sound production, hearing, noise effect, and passive acoustic monitoring on cetaceans have been developed over 60 years since 1950s in the world. There are almost 40 cetaceans documented in Chinese waters, including the Yangtze River dolphin and Yangtze finless porpoise unique to the middle and lower reaches of the Yangtze River. The conservation-related bioacoustics researches on cetaceans in Chinese waters were initiated in 1980s with the Yangtze River dolphin and Yangtze finless porpoise, and being extended to Indo-Pacific humpback dolphins, Bryde’s whales, and other cetacean species in the South China Sea, East China Sea, and Yellow Sea, which were accelerated by Dr. Paul Nachtigall, through his publications and supervision. These efforts have shed light on behaviour, ecology, population status, distribution pattern, and so on, for the investigated animals, and benefited protection policy designation and management for the concerned species. This presentation will summarize the achievements of these efforts in the past 40 years.

Aquariums worldwide have undergone substantial growth in both scale and number in recent decades. However, the issue of anthropogenic underwater noise pollution within these facilities and its impact on cetaceans has been largely neglected. Here, we examined underwater sound levels in an aquarium during both the tourist rush season and the off-season, alongside the corresponding audiogram, of an Indo-Pacific humpback dolphin. Results indicated that sound exposure levels during the aquarium's opening hours were significantly higher than during non-opening hours. Likewise, the daily cumulative auditory-weighted sound exposure level (SELcw) during the tourist rush season (180 dB) exceeded the threshold for the onset of temporary threshold shifts (TTS) in humpback dolphins (178 dB). By contrast, the daily SELcw during the tourist off-season (173 dB) remained below the threshold for the onset of TTS in humpback dolphins. The dolphin audiogram obtained during the tourist rush season revealed an elevated level of 14 +/- 11 dB compared to levels observed during the tourist off-season. Approximately 41% of the dolphin's auditory thresholds exhibited an elevation exceeding 20 dB. The increased frequency of openings, resulting in extended cumulative opening hours during the tourist rush season, led to elevated sound exposure, which induced TTS in the dolphins. The findings underscore the critical need for meticulous control measures, such as tracking cumulative operating hours, and are essential for informing the development of appropriate welfare standards for animals in both captivity and the wild.

In response to our recent paper1 using classical poems to study range contraction of the Yangtze finless porpoise (Neophocaena asiaeorientalis), Wang et al.2 raised several concerns, primarily arguing that additional poems related to Yangtze finless porpoises should not be ignored, that ancient poets may have confused the Baiji (Lipotes vexillifer) and the Yangtze finless porpoise and that our dataset includes duplicated data points and incorrectly identified locations. We appreciate open and constructive dialogue, and we would like to address some misunderstandings by providing clarity and defending our perspective.

Nature reserves in the Yangtze River, China, are crucial for protecting the Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) and their habitats. Despite a 10-year fishing ban along the middle and lower reaches of the Yangtze River instated on January 2020 to alleviate pressures on the porpoise's prey, other stressors, particularly underwater noise, continue to impact these rare cetaceans, which rely heavily on vocalization for prey detection, communication and navigation. Between September 2020 and September 2021, underwater noise monitoring was carried out in the Xinluo Baiji National Nature Reserve, located in Hubei province, China, with the aim of assessing the potential impact of underwater noise pollution on the Yangtze finless porpoise. The reserve was divided into 30 sub-sections to systematically monitor underwater noise across the reserve. Passive acoustic monitoring was conducted at each site within these sub-sections during four sampling periods, and these data were subjected to comparative analysis with data collected in 2012 and 2017. The results showed that the root mean square sound pressure levels at each site ranged from 117 to 162 dB. Power spectral levels (11.2-152 kHz) exceeded the average audiogram levels for the porpoise at most sites. 94.2% and 93.3% of the sites exceeded underwater acoustic thresholds known to induce a hearing threshold shift for the porpoise in terms of both the averaged cumulative unweighted sound exposure level, and cumulative weighted sound exposure level respectively. Noise levels in this section during 2020-2021 were approximately 25 and 30 dB higher compared to the levels recorded in 2012 and 2017, and likely due to increased shipping activity and the proximity of sampling sites to the shipping channel. The rise in noise levels might contribute to the observed declines in the porpoise population within this area. To mitigate these impacts, implementing noise control measures is essential, such as regulating navigation speed and limiting the number of vessels in the reserve.

Aquariums globally have seen significant growth in recent decades. However, persistent negligence exists concerning underwater sound pollution in aquariums and its impact on cetaceans. Here, the audiogram of Taotao, the world's first successfully captive-born and bred Yangtze finless porpoise, and the underwater sound levels in the Baiji Aquarium at the Institute of Hydrobiology, Chinese Academy of Sciences were examined. In contrast to the previously published U-shaped audiograms of the Yangtze finless porpoise, Taotao's audiogram exhibited a W-shaped pattern. Additionally, the audiogram of Taotao was, on average, 42 ± 15 dB (mean ± SD) higher than that of other non-aquarium-born Yangtze finless porpoises in the Baiji Aquarium and 43 ± 11 dB higher than that of wild Yangtze finless porpoises, particularly in the 20-60 kHz range and at 90 kHz. The underwater sound spectra in the Baiji Aquarium do not account for the notches observed in the porpoise's audiogram below 60 kHz, suggesting that congenital hearing disorders may be the cause of Taotao's hearing loss in these frequency bands. In contrast, the cumulative weighted broadband sound exposure levels of underwater sound within the aquarium (mean: 162 dB) exceeded the temporary threshold shift onset threshold for non-impulsive noise (153 dB) and the permanent threshold shift onset threshold for impulsive noise (155 dB) in finless porpoises. The high levels of underwater sound exposure, particularly from conspecific porpoises, highlight the need for increased focus on the welfare of captive animals.

ABSTRACTEvaluating the effectiveness of freshwater protected areas (FPAs) is crucial for improving their performance, yet evidence remains limited. Using remote sensing and field surveys from 2001 to 2017, we examined FPA coverage, their efficacy in preventing species decline and habitat deterioration, and strategies to enhance FPA effectiveness for the critically endangered Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis). FPAs failed to cover nearly half of high‐abundance regions and two thirds of medium‐abundance areas. Despite initially better conditions, FPAs experienced similar or greater species declines and habitat deterioration. Porpoise distribution closely correlated to habitat conditions, with abundance declining most in severely degraded floodplains while remaining stable or increasing in less disturbed areas. To improve FPA performance, we recommend expanding protection to medium‐ and high‐abundance areas to better cover key porpoise habitats and enhancing existing FPAs through stricter law enforcement, proactive management, and targeted restoration. These strategies are reinforced by China's new legal and policy framework for Yangtze River protection, providing a foundation for long‐term conservation.

Sand mining has emerged as a pervasive environmental crisis with profound consequences for freshwater ecosystems. However, current conservation efforts primarily focus on regulating mining intensity, often neglecting the long-term ecological consequences that may lead to unforeseen risks. Here, we integrated 20 years of remote sensing data on sand dredging activities with eight field surveys of the megafauna, Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) in Poyang Lake, to investigate the long-term impacts of sand mining. Our findings revealed that high-density sand mining creates numerous water-filled depressions during the dry season (equivalent to 153.5 % of the original lake area), which we refer to as sand traps. These activities exert dual impacts on porpoise populations: high-intensity dredging significantly limits porpoise distribution during active mining (p = 0.031); whereas the expansion of sand traps attracts porpoises after mining ceases (p = 0.0016). Within sand trap areas, untransported sediments accumulate to form sand reefs, leading to irregular water depth. Moreover, under extreme dry events, the expansion rate of sand reefs (<1 m water depths) within sand traps is 2.15 times higher than that outside them, further exacerbating the risk of megafauna stranding. In addition to controlling mining intensity, our study highlights the urgent need for mitigating long-term stranding risks from sand mining through ecological water level management, intensified patrolling, and targeted dredging, particularly amid the increasing frequency of extreme drought events.

Understanding and quantifying the historical range of threatened species can help inform conservation and restoration1. Most studies use specimen data, molecular evidence or past surveys to reconstruct historical ranges. However, historical documents provide a unique opportunity to reconstruct species' distributions and ranges, offering new perspectives on changes in biodiversity. Several recent studies have shown that historical documents, such as standard histories and gazetteers2 or compendia of the genealogy of plants or animals3, can be used to reconstruct species distributions. For example, compendium records in China revealed severe and rapid contraction of mammalian megafauna ranges over the past two millenia4. Here, we examine an unusual source of information: classic Chinese poetry. From 724 ancient poems containing references to the Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis), we infer that the range of this subspecies has contracted by at least 65% over the past 1400 years.

Ex situ conservation and population reinforcements or reintroductions are vital strategies for protecting endangered species, yet efforts for cetaceans have been notably limited. Through post-release monitoring based on wearable radio tag and passive acoustic methods, we report the first successful release of a critically endangered small toothed whale, the Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis), into the wild. Our monitoring results indicate that, by the third day after release, the two porpoises from the ex situ population had joined a local individual and gradually integrated into the core distribution area of the local population. Continuous monitoring by the Yangtze Cetacean Protection Network revealed no recorded deaths among the released porpoises. This successful release demonstrates the potential of this approach as a supplementary measure for the restoration of the Yangtze finless porpoise wild population.

It is urgent to identify novel early diagnostic markers and therapeutic targets for non-small-cell lung cancer (NSCLC), which accounts for 85% of lung cancer cases and has a 5-year survival rate of 4–17%. Here, chromatin immunoprecipitation (ChIP) was used to identify DNA‒protein interactions, RNA methylation was determined by methylated RNA immunoprecipitation (MeRIP), RNA stability was tested by an RNA decay assay. We showed that RAD21, a member of the cohesin complex, is upregulated in NSCLC tissues and cell lines and found to be an independent prognostic factor for overall survival (OS) of NSCLC patients. Mechanistically, the cohesin loading factor Nipped-B-Like Protein (NIPBL) promoted RAD21 gene transcription by enhancing histone H3 lysine 27 (H3K27) demethylation via recruiting lysine demethylase 6B (KDM6B) to the RAD21 gene promoter. RAD21 enhanced phosphatidylinositol 3-kinase (PI3K) gene transcription, and NIPBL reversed the effect of enhancer of zeste 2; catalytic subunit of polycomb repressive complex 2 (EZH2) on RAD21-mediated PI3K gene transcription by disrupting the association between EZH2 and RAD21. Moreover, NIPBL level was increased by stabilization of its transcripts through mRNA methylation. These findings highlight the oncogenic role of RAD21 in NSCLC and suggest its use as a potential diagnostic marker and therapeutic target for NSCLC.

The Yangtze finless porpoise (YFP) is an endemic freshwater cetacean species that exclusively inhabits the middle and lower reaches of the Yangtze River basin. Since the late 1970s, the YFP has experienced a drastic population decline and was classified as critically endangered by the IUCN in 2013. To save this unique species, a range of integrated conservation measures have been implemented, including strengthening natural habitat protection (in-situ), enhancing insurance populations (ex-situ), and advancing captive breeding and research initiatives. These efforts have yielded significant progress in the conservation of the YFP. The natural population has been starting to increase after a sharp decline, and the establishment of three insurance populations has provided a solid foundation for recovery. Additionally, advancement in captive breeding and research has delivered crucial technical support for population conservation. As a flagship species of Yangtze River biodiversity and an indicator of the river’s ecosystem health, the YFP’s integrated conservation strategy not only benefits its own population but also offers valuable insights for the protection of other endangered aquatic species in the Yangtze River and other threatened small cetaceans worldwide.

AbstractNumerous dams disrupt freshwater animals. The uppermost population of the critically endangered Yangtze finless porpoise has been newly formed below the Gezhouba Dam, however, information regarding the local porpoise is scarce. Passive acoustic monitoring was used to detect the behaviors of porpoises below the Gezhouba Dam. The influence of shipping, pandemic lockdown, hydrological regime, and light intensity on the biosonar activity of dolphins was also examined using Generalized linear models. Over the course of 4 years (2019–2022), approximately 848, 596, and 676 effective monitoring days were investigated at the three sites, from upstream to downstream. Observations revealed significant spatio‐temporal biosonar activity. Proportion of days that are porpoise positive were 73%, 54%, and 61%, while porpoise buzz signals accounted for 78.49%, 62.35%, and 81.30% of all porpoise biosonar at the three stations. The biosonar activity of porpoises was much higher at the confluence area, particularly at the MZ site, during the absence of boat traffic, and during the Pandemic shutdown. Temporal trends of monthly, seasonal, and yearly variation were also visible, with the highest number of porpoises biosonar detected in the summer season and in 2020. Significant correlations also exist between the hydrological regime and light intensity and porpoise activity, with much higher detections during nighttime and full moon periods. Hydropower cascade development, establishment of a natural reserve, fish release initiatives, and implementation of fishing restrictions may facilitate the proliferation of the porpoise population downstream of the Gezhouba Dam within the Yichang section of the Yangtze River. Prioritizing restoration designs that match natural flow regimes, optimize boat traffic, and reduce noise pollution is crucial for promoting the conservation of the local porpoises.

The Yangtze finless porpoises (Neophocaena asiaeorientalis a.) are an endemic and critically endangered species in China. Intensive captive breeding is essential for understanding the biology of critically endangered species, especially their pregnancy characteristics, knowledge of which is crucial for effective breeding management. Urine metabolomics can reveal metabolic differences, arising from physiological changes across pregnancy stages. Therefore, we used the urinary metabolomic technology, to explore urinary metabolite changes in pregnant Yangtze finless porpoises. A total of 2281 metabolites were identified in all samples, which including organic acids and derivatives (24.45%), organoheterocyclic compounds (20.23%), benzenoids (18.05%), organic oxygen compounds (7.73%), and phenylpropanoids and polyketides (6.48%). There were 164, 387, and 522 metabolites demonstrating differential abundance during early pregnancy, mid pregnancy, and late pregnancy, respectively, from the levels observed in nonpregnancy. The levels of pregnenolone, 17α-hydroxyprogesterone, and tetrahydrocortisone were significantly higher during all pregnancy stages, indicating their important roles in fetal development. The differential metabolites between nonpregnancy and pregnancy were mainly associated with amino acid and carbohydrate metabolism. Moreover, metabolic activity varied across pregnancy stages; steroid hormone biosynthesis was predominant in early pregnancy, and amino acid biosynthesis and carbohydrate metabolism were predominant in mid pregnancy and late pregnancy, respectively. Our results provide new insights into metabolic characteristics in the Yangtze finless porpoises’ urine during pregnancy, and indicate that the differential levels of urine metabolites can determine pregnancy in Yangtze finless porpoises, providing valuable information for the husbandry and management of pregnant Yangtze finless porpoises in captivity.

The establishment of marine protected areas (MPAs) for cetaceans is an important strategy to mitigate human disturbance and protect biodiversity. Despite abundant cetacean species, there are only a few MPAs dedicated to cetacean conservation in China, all of which are for inshore dolphins. Bryde's whales, the only nearshore baleen whale population in mainland China, are conflicting with intensive human activities, yet an effective conservation strategy is lacking. This study used species distribution models to analyze distribution patterns and suitable habitats of Bryde's whales in the Beibu Gulf and proposes the first baleen whale MPA in China. Our results showed Bryde's whales have a seasonal distribution pattern in the Beibu Gulf, and that the waters around Weizhou Island and the southeastern coast of Vietnam were their core habitats. The seasonal nighttime light data indicated a negative relationship between the number of ship lights and Bryde's whale sightings and suggest that Bryde's whales might be threatened by fisheries. We proposed an MPA based on the results, suggesting that the waters within 20 km around Weizhou Island should be declared a protected area. Furthermore, we recommend that anthropogenic activities in the waters around Weizhou Island are better managed to reduce negative impacts on marine life.

Image processing using traditional photogrammetric methods is a labor-intensive process. The collection of photogrammetry images during aerial surveys is expanding rapidly, creating new challenges to analyze images promptly and efficiently, while reducing human error during processing. Computer vision-assisted photogrammetry, a field of artificial intelligence (AI), can automate image processing, greatly enhancing the efficiency of photogrammetry. Here, we present a practical and efficient program capable of automatically extracting the fine-scale photogrammetry of East Asian finless porpoises (Neophocaena asiaeorientalis sunameri). Our results indicated that computer vision-assisted photogrammetry could achieve the same accuracy as traditional photogrammetry, and the results of the comparisons were validated against the direct measurements. Three-dimensional (3D) models using computer vision-assisted photogrammetric morphometrics generated trustworthy body volume estimates. We also explored the one image-based 3D modeling technique, which is less accurate, but still useful when only one image of the animal is available. Although several limitations exist in the current program, improvements could be made to narrow the virtual-reality gap when more images are available for machine learning and training. We recommend this program for analyzing images of marine mammals possessing a similar morphological contour.

Anthropogenic disturbances have led to an increase in nocturnal activities among terrestrial species[1],but their influence on aquatic mammals is still unknown.Among these,small odontocetes in fresh-water and nearshore environments are facing significant human-induced pres-sures[2,3],particularly from prevalent and growing shipping traffic[4].The'anthropause'due to the COVID-19 lock-down provided a valuable opportunity to study the effect of shipping on the diel rhythms of small odontocetes.