Changes in Population Characteristics of Marine and Freshwater Organisms and Their Environmental Driving Factors

A special issue of Animals (ISSN 2076-2615). This special issue belongs to the section "Aquatic Animals".

Deadline for manuscript submissions: 10 June 2025 | Viewed by 6403

Special Issue Editor

East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, China
Interests: spatial–temporal dynamics; marine ecology; fish community; environmental impact
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

With global warming and climate change, the habitats of marine and freshwater organisms have undergone drastic changes, resulting in a series of changes in their population biology and dynamic distribution characteristics. Especially in the past decade, rapid changes in the water temperature and warming trends have caused significant variations in the abundance and spatial distribution of marine and freshwater organisms, with some marine organisms showing a clear trend of moving towards the South Arctic or deep sea. The traditional habitats or fishing grounds of some important economic species have also undergone significant changes, and the stability of their suitable habitats or fishing grounds has declined year by year. The reason for this change may be that the severe fluctuations in the marine environment have affected the normal growth and reproduction of biological populations, thereby altering their population structure and resource spatial distribution. Identifying and understanding the impact of key marine and freshwater environmental factors on the abundance and life history characteristics of biological populations can help us better understand the resource status of these organisms, assess and develop management measures, as well as better protect these biological populations. With the development of modern research methods such as machine learning, especially deep learning, satellite remote sensing, and physical ocean models, the monitoring, simulation, and prediction of habitat distribution and life history processes of biological resources have become more scientific, detailed, and identifiable. This will further help us to correctly understand the self-evolution laws and healthy development of biological populations.

In this Special Issue, original research articles and reviews are welcome. Research areas may include (but not limited to) the above.

We look forward to receiving your contributions.

Dr. Heng Zhang
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Animals is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • population characteristics
  • spatial–temporal dynamics
  • biology
  • environmental factor
  • climate change
  • species distribution
  • eDNA
  • resource abundance
  • marine and freshwater organisms

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (8 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

14 pages, 1090 KiB  
Article
Insights into the Genetic Connectivity and Climate-Driven Northward Range Expansion of Turbo sazae (Gastropoda: Turbinidae) Along the Eastern Coast of Korea
by Young-Ghan Cho, Kyungman Kwon, Hyun Soo Rho, Won-Gi Min, Hee-Do Jeung, Un-Ki Hwang, Yong-Kyun Ryu, Areumi Park, Hyun-Ki Hong, Jong-Seop Shin and Hyun-Sung Yang
Animals 2025, 15(9), 1321; https://doi.org/10.3390/ani15091321 - 2 May 2025
Viewed by 65
Abstract
Turbo sazae, a commercially and ecologically significant marine gastropod traditionally found in Jeju Island and the southern coast of Korea, is experiencing a reported northward expansion into the East Sea, likely influenced by rising seawater temperatures. This study provides preliminary genetic insights [...] Read more.
Turbo sazae, a commercially and ecologically significant marine gastropod traditionally found in Jeju Island and the southern coast of Korea, is experiencing a reported northward expansion into the East Sea, likely influenced by rising seawater temperatures. This study provides preliminary genetic insights into the genetic structure and connectivity of T. sazae populations between Jeju and the East Sea using mitochondrial COI sequences. Samples from 6 geographically distinct locations were analyzed, with three cloned replicates generated to enhance sequence reliability. Genetic diversity, haplotype distribution, and population differentiation were then assessed. Our analysis reveals potential genetic connectivity between Jeju and East Sea populations, possibly driven by larval dispersal via the Kuroshio and Tsushima Currents, highlighted by the predominance of shared haplotype EJ1 (60.0% in Jeju, 50.0% in East Sea). Bayesian phylogenetic analysis estimated the time to the most recent common ancestor (MRCA) between Jeju and East Sea populations at approximately 9.7 to 23.3 million years ago, indicating ancient divergence rather than very recent separation. Pairwise FST values and AMOVA results showed generally low levels of genetic differentiation. Given the small sample sizes and use of a single mitochondrial marker, these findings should be interpreted cautiously as preliminary evidence. Nevertheless, this study highlights the need for continued genetic monitoring of T. sazae populations under climate-driven range shifts and provides a foundation for future research incorporating broader genomic approaches. Full article
Show Figures

Figure 1

17 pages, 2783 KiB  
Article
The Spatio-Temporal Distribution and Population Dynamics of Chub Mackerel (Scomber japonicus) in the High Seas of the Northwest Pacific Ocean
by Guoqing Zhao, Heng Zhang and Fenghua Tang
Animals 2025, 15(8), 1135; https://doi.org/10.3390/ani15081135 - 15 Apr 2025
Viewed by 269
Abstract
Chub mackerel (Scomber japonicus) is a typical small pelagic fish in the high seas of the Northwest Pacific Ocean (NPO), with great ecological and economic values. It is crucial to understand the spatio-temporal distribution and the population dynamics of chub mackerel for [...] Read more.
Chub mackerel (Scomber japonicus) is a typical small pelagic fish in the high seas of the Northwest Pacific Ocean (NPO), with great ecological and economic values. It is crucial to understand the spatio-temporal distribution and the population dynamics of chub mackerel for commercial fishing and fishery management. In this study, we analyzed the population dynamics and stock status of chub mackerel based on commercial fishing data. Results showed that from 2016 to 2021, high catches of chub mackerel were concentrated along the outer edge of Japan or Russia’s exclusive economic zone line, and the gravity center of the fishing grounds moved to the northwest gradually, with a decrease in the average value of catch per unit effort (CPUE) year by year. The fishing pressure may not be the major reason for the decrease in chub mackerel as the resource biomass was at a high level. The body length structure was reasonable, and large individuals were still present. The study highlights the fact that the population status of chub mackerel was healthy in 2016–2021 according to our results. However, it has to be emphasized that resource exploitation and fishery management also need to take into account the influence of climatic conditions. Full article
Show Figures

Figure 1

14 pages, 3614 KiB  
Article
Diel Vertical Migration and Transport Pattern of Larvae and Juveniles of the Small Yellow Croaker (Larimichthys polyactis) in the Yangtze River Estuary
by Xiaojing Song, Fen Hu, Jianzhong Ling, Xingwei Yuan, Zunlei Liu, Yan Jin, Shengfa Li and Yazhou Jiang
Animals 2025, 15(8), 1128; https://doi.org/10.3390/ani15081128 - 14 Apr 2025
Viewed by 235
Abstract
In order to understand the diel vertical migration and transport pattern during their early life stages, the vertical distribution of larvae and juveniles of the small yellow croaker (Larimichthys polyactis) in the Yangtze River estuary was investigated. Four sampling cycles were [...] Read more.
In order to understand the diel vertical migration and transport pattern during their early life stages, the vertical distribution of larvae and juveniles of the small yellow croaker (Larimichthys polyactis) in the Yangtze River estuary was investigated. Four sampling cycles were carried out at the station (122°39′ E, 31° N) during May and June 2015. The samples were collected by vertically discrete plankton hauls in three strata of the water column: surface (0~2 m depth), middle (8~10 m depth), and bottom (18~20 m depth). The total number of small yellow croaker larvae was 5523, of which 65.2% and 25.8% were postflexion larvae and juveniles, respectively. Most of the individuals were collected in mid-May, and the sum of the quantity in May accounted for 94.8%. In all cruises, the highest abundance occurred at the bottom, while the surface maintained the lowest abundance. The flexion larvae, postflexion larvae and juveniles moved up to the surface and middle at night, but there was no significant difference between night and daytime for preflexion larvae in each stratum. The postflexion larvae and juveniles showed low temperature responses and a preference for the bottom habitat, respectively, while the preflexion and flexion larvae had weaker selectivity to the water layer and occurrence time. The abundance of larvae and juveniles in the middle layer was significantly higher at flood tide than at ebb tide, and it was more dominant at night than during the day. The study indicates that larvae and juveniles of the small yellow croaker change their located depth with diel vertical migration and utilize the faster speed of the mid-upper layer, which contributes to their ingress into the Yangtze River estuary nursery ground. Full article
Show Figures

Figure 1

21 pages, 5458 KiB  
Article
Cumulative Ecological Impact of Cascade Hydropower Development on Fish Community Structure in the Main Stream of the Xijiang River, China
by Yuansheng Zhu, Jiayang He, Fangyuan Xiong, Zhiqiang Wu, Jiajun Zhang, Yusen Li, Yong Lin, Anyou He, Dapeng Wang and Yaoquan Han
Animals 2025, 15(4), 495; https://doi.org/10.3390/ani15040495 - 10 Feb 2025
Viewed by 736
Abstract
In recent decades, dams worldwide are increasingly constructed in a row along a single river or basin, thus forming reservoir cascades, and in turn producing cumulative ecological effects along these areas. The use of multimetric indices (MMI) based on fish assemblages to assess [...] Read more.
In recent decades, dams worldwide are increasingly constructed in a row along a single river or basin, thus forming reservoir cascades, and in turn producing cumulative ecological effects along these areas. The use of multimetric indices (MMI) based on fish assemblages to assess the ecological health status of rivers and lakes has also been extensively developed. However, to date, there are no studies that employ MMI for the identification of the cumulative effects of reservoir cascades. The aim of this study was to develop a new Fish-based Index of Biotic Integrity (F-IBI) that can effectively identify the cumulative effects of reservoir cascades on fish assemblages in two important habitats (the free-flowing reach between reservoirs and the transition zone in the reservoir). Fish assemblages from 12 sites were sampled along the cascade reservoirs in the Xijiang River, China. First, through screening for redundancy, precision, and responsiveness of the candidate metrics, a new F-IBI based on ecological trait information of fish species composition was developed to estimate the ecological status of all sites. F-IBI scores exhibited an obviously downward trend from upstream to downstream in a reservoir cascade, and the transition zones in the reservoir displayed significantly lower F-IBI scores than the free-flowing reaches between reservoirs. Secondly, using Random Forest models, it was shown that the F-IBI can effectively identify the cumulative effects of the reservoir cascades on fish assemblages. Furthermore, we also demonstrated metric-specific responses to different stressors, particularly the multiple reservoir cascades, which showed the following: (1) The F-IBI index system developed based on the Random Forest model can effectively identify the superimposed effects of cascade power stations on fish integrity changes, with the cumulative time effect and the GDP index of river segments playing a key role; (2) To effectively protect the fish resources in the main stream of the Xijiang River, where priority should be given to the habitat of the natural flowing river sections between the reservoirs. At the same time, environmental regulatory policies should be formulated accordingly based on the human development status of each river section. Full article
Show Figures

Figure 1

20 pages, 4075 KiB  
Article
Post-Fishing Ban Period: The Fish Diversity and Community Structure in the Poyang Lake Basin, Jiangxi Province, China
by Chiping Kong, Yulan Luo, Qun Xu, Bao Zhang, Xiaoping Gao, Xianyong Wang, Zhen Luo, Zhengli Luo, Lekang Li and Xiaoling Gong
Animals 2025, 15(3), 433; https://doi.org/10.3390/ani15030433 - 4 Feb 2025
Viewed by 926
Abstract
Between 2022 and 2023, four systematic fish surveys were carried out in the Poyang Lake basin (PLB), capturing 49,192 fish (7017 kg) and identifying 120 species from 10 orders, 21 families, and 70 genera. Cypriniformes were the most dominant, accounting for 79 species. [...] Read more.
Between 2022 and 2023, four systematic fish surveys were carried out in the Poyang Lake basin (PLB), capturing 49,192 fish (7017 kg) and identifying 120 species from 10 orders, 21 families, and 70 genera. Cypriniformes were the most dominant, accounting for 79 species. The spring and autumn surveys collected 25,734 and 23,458 individuals, respectively, with corresponding biomasses of 3978 kg and 3038 kg. Dominant species (IRI > 1000) in the study area included Hemiculter leucisculus, Megalobrama skolkovii, Hypophthalmichthys molitrix, and Aristichthys nobilis. Additionally, critically endangered species such as Ochetobius elongatus, Myxocyprinus asiaticus, and Acipenser sinensis as well as exotic species like Cirrhinus mrigala and euryhaline species like Cynoglossus gracilis and Hyporhamphus intermedius were observed. Hierarchical clustering grouped the survey stations into three distinct areas (PYS, XBMS, and XBUS), with the ANOSIM analysis showing highly significant differences (R = 0.893, p < 0.01). Redundancy analysis (RDA) indicated that in spring, total phosphorus (TP) and temperature were the main factors influencing variability (80.50%), while in autumn, temperature, oil, and pH were the key factors (75.20%). This study emphasizes the predictable changes in fish community composition caused by environmental gradients and highlights the need for ongoing monitoring to effectively manage and protect the ecosystem, particularly in the post-fishing ban period. Full article
Show Figures

Figure 1

48 pages, 4979 KiB  
Article
Evaluating Ecosystem Characteristics and Ecological Carrying Capacity for Marine Fauna Stock Enhancement Within a Marine Ranching System
by Jie Feng, Haolin Yu, Lingjuan Wu, Chao Yuan, Xiaolong Zhao, Huiying Sun, Cheng Cheng, Yifei Li, Jingyi Sun, Yan Li, Xiaolong Wang, Yongjun Shang, Jiangling Xu and Tao Zhang
Animals 2025, 15(2), 165; https://doi.org/10.3390/ani15020165 - 10 Jan 2025
Cited by 1 | Viewed by 827
Abstract
China has recently launched extensive marine ranching projects, highlighting the need for scientific evaluation of ecosystem structure and function to guide their development. This study established two energy flow models and an evaluation index system to assess the structure, function, carrying capacity, and [...] Read more.
China has recently launched extensive marine ranching projects, highlighting the need for scientific evaluation of ecosystem structure and function to guide their development. This study established two energy flow models and an evaluation index system to assess the structure, function, carrying capacity, and ecological status of both a marine ranching ecosystem and a nearby control site in the Beibu Gulf. The results show that the ranching ecosystem outperformed the control ecosystem in terms of food chain length, system size, and ecological carrying capacity of economically important species. The ranching ecosystem was classified as “relatively good”, while the control ecosystem was deemed “relatively poor”, which may confirm the success of the ranching efforts. Mussels, large crabs, and scorpaenidae were identified as key species for stock enhancement based on their biomass potential. Scenario simulations using Ecosim, driven by biomass and fishing factors, indicate that stock enhancement strategies targeting MOB (mussels, oysters, and barnacles) significantly improved the ranching ecosystem, raising its status to “good”. However, the simulations also revealed that stock enhancement had limited effects on optimizing food web structure, system organization, and energy transfer efficiency, suggesting that a combination of strategies is necessary for further improvement. Full article
Show Figures

Figure 1

14 pages, 3085 KiB  
Article
Long-Term Variations in Habitat Use of Humpback Dolphins Due to Anthropogenic Activities in Western Pearl River Estuary
by Xinxing Wang, Min Li, Liang Fang, Tao Chen and Wenhua Liu
Animals 2024, 14(23), 3381; https://doi.org/10.3390/ani14233381 - 24 Nov 2024
Viewed by 1029
Abstract
Marine mammals near coastlines are highly vulnerable to human activities like rapid industrialisation, port construction, and sea reclamation, which can alter their habitat use. This study examines changes in the habitat use of Indo-Pacific humpback dolphins in the western Pearl River Estuary (WPRE) [...] Read more.
Marine mammals near coastlines are highly vulnerable to human activities like rapid industrialisation, port construction, and sea reclamation, which can alter their habitat use. This study examines changes in the habitat use of Indo-Pacific humpback dolphins in the western Pearl River Estuary (WPRE) by employing a kernel density estimation model that considers physical barriers. Sighting records from systematic surveys in 2007–2008 and 2019–2020, along with remote sensing data, were used to analyse changes in shorelines and areas affected by maritime projects since 1973. Approximately 552.98 km2 of water was permanently lost to reclamation between 1973 and 2020. In 2007–2008, dolphins preferred natural shorelines, while reclamation drove them away from artificial ones. By 2019–2020, their core habitat had decreased by two-thirds, with some areas disappearing, likely due to aquaculture expansion. These results highlight the importance of adopting improved environmental assessment methodologies in the planning and regulation of aquaculture activities in the WPRE to better protect the dolphin habitat. Full article
Show Figures

Figure 1

16 pages, 9215 KiB  
Article
Spatial Distribution and Growth Patterns of a Common Bivalve Mollusk (Macoma calcarea) in Svalbard Fjords in Relation to Environmental Factors
by Alyona E. Noskovich and Alexander G. Dvoretsky
Animals 2024, 14(23), 3352; https://doi.org/10.3390/ani14233352 - 21 Nov 2024
Cited by 2 | Viewed by 733
Abstract
Ongoing warming in the Arctic has led to significant sea-ice loss and alterations in primary production, affecting all components of the marine food web. The considerable spatial variability of near-bottom environments around the Svalbard Archipelago renders the local fjords promising sites for revealing [...] Read more.
Ongoing warming in the Arctic has led to significant sea-ice loss and alterations in primary production, affecting all components of the marine food web. The considerable spatial variability of near-bottom environments around the Svalbard Archipelago renders the local fjords promising sites for revealing responses of benthic organisms to different environmental conditions. We investigated spatial variations in abundance, biomass, and growth parameters of the common bivalve Macoma calcarea in waters off western Spitsbergen and identified two distinct groups of this species: one composed mainly of cold-water stations from Storfjorden (Group I) and the other comprising warmer-water stations from Grønfjorden and Coles Bay (Group II). Within these groups, the mean abundance, biomass, production, and mortality accounted for 0.2 and 429 ind. m−2, 20 and 179 g m−2, 18.5 and 314 g m−2 year−1, and 0.22 and 0.10 year−1 respectively. The size–frequency and age–frequency distributions were biased towards smaller and younger specimens in Group I, while Group II displayed more even distributions. The maximum ages were 11 and 21 years, respectively. The mollusks from cold water were significantly smaller than their same-aged counterparts from warmer water. Two groups of Macoma were identified: slow-growing individuals with a rate of 1.4 mm and fast-growing individuals with a growth rate of 1.8 mm. Most population parameters were higher than those observed in the Pechora, Kara, and Greenland Seas. Redundancy analysis indicated water temperature as the main driving factor of abundance and biomass, while the latter was also influenced by the presence of pebbles. Our findings provide new insights into the growth patterns and spatial distribution of Macoma at high latitudes and confirm that this species can serve as a reliable indicator of environmental conditions. Full article
Show Figures

Figure 1

Back to TopTop