scholarly journals Length-weight relationships of the ichthyofauna from a coastal subtropical system: a tool for biomass estimates and ecosystem modelling

2016 ◽  
Vol 16 (3) ◽  
Author(s):  
André Martins Vaz-dos-Santos ◽  
Bárbara Gris
Keyword(s):  
Fish Species ◽  
Growth Pattern ◽  
Coastal Area ◽  
Fish Populations ◽  
Life Stages ◽  
Ecosystem Modelling ◽  
Economic Aspects ◽  
Albula Vulpes ◽  
System A

Abstract Aiming to analyse the growth pattern, to allow biomass estimates and consequently to subsidize the ecosystem modelling, the length-weight relationships (LWR) of 39 fish species from the Araçá Bay, a subtropical coastal area chosen as model for a holistic study comprising environmental, social and economic aspects have been estimated. The objective of this study was to provide LWR for the fishes from the area itself, accurately based on the life stages of fish populations present there. Particularly for Albula vulpes, Trachinotus carolinus, T. falcatus, Archosargus rhomboidalis and Kyphosus sectatrix these are the first records of LWR in Brazil.

scholarly journals Preliminary assessment of surf-zone and estuarine line-fish species of the Dwesa-Cwebe Marine Protected Area, Eastern Cape, South Africa

Koedoe ◽  
2012 ◽  
Vol 54 (1) ◽  
Author(s):  
Jan A. Venter ◽  
Bruce Q. Mann
Keyword(s):  
South Africa ◽  
Law Enforcement ◽  
Fish Species ◽  
Protected Area ◽  
Surf Zone ◽  
Marine Protected Area ◽  
Fish Populations ◽  
Estuarine Fish ◽  
Catch Per Unit Effort ◽  
Preliminary Assessment

A preliminary assessment of surf-zone and estuarine line fish was carried out in the DwesaCwebe Marine Protected Area (MPA), on the Wild Coast, South Africa. The purpose was to provide baseline data on inshore line-fish stocks in the MPA. A total of 28 species was recorded, of which 53% have a conservation status reflecting some concern and 43% are endemic to southern Africa. This highlights the value of the MPA for protection of important line-fish species. Within the MPA, localised differences were detected in species diversity, size frequency and catch per unit effort between unexploited and illegally exploited areas. These differences were more prominent in slow growing, long-lived species. It thus appears that illegal exploitation is negatively affecting fish populations within the MPA, which counteract and potentially could eliminate the benefits of fish protection typically associated with no-take MPAs. These results highlight the need for improved law enforcement and better communication with neighbouring communities to increase awareness. It is further recommended that the current no-take status of the MPA should be maintained. In addition, baseline fisheries information was collected on certain fish species that could be used to inform future conservation management of the MPA.Conservation implications: The Dwesa-Cwebe Marine Protected Area is unique and important for the conservation of key surf zone and estuarine fish species. However there is a significant risk to the fish populations due to illegal exploitation. Key interventions should include enhanced law enforcement but, more important, the creation of alternative livelihoods and long term sustainable benefits to local communities.

scholarly journals Prevalence of Anisakis Larvae in Different Fish Species in Southern Albania: Five-Year Monitoring (2016–2020)

2021 ◽  
Vol 11 (23) ◽  
pp. 11528
Author(s):  
Enkeleda Ozuni ◽  
Ani Vodica ◽  
Marta Castrica ◽  
Gabriele Brecchia ◽  
Giulio Curone ◽  
...  
Keyword(s):  
Fish Species ◽  
Coastal Area ◽  
Sparus Aurata ◽  
Dicentrarchus Labrax ◽  
Health Impact ◽  
Coelomic Cavity ◽  
Farmed Fish ◽  
Risk Area ◽  
High Risk Area ◽  
Negative Results

Anisakidae are nematodes that commonly parasitize in the coelomic cavity and viscera of several fish species. They can be found in flesh, which is why they have an important economic and public health impact. The aim of the current work was to assess the presence and prevalence of Anisakis larvae in fish species caught in the coastal area of the Karaburun Peninsula in Vlora Bay (Albania). A total of 856 of wild teleosts and 219 specimens of farmed fish were collected over a 5-year period (from 2016 to 2020). The results showed that out of a total of 1075 analyzed samples, 361 (33.58%) were parasitized with L3 larvae. In particular, only Solea vulgaris returned negative results, while Sparus aurata, Dicentrarchus labrax, and Sardinella aurita showed the lowest prevalence (4.55%, 9.17%, and 10.53%, respectively) and mean abundance (0.84, 1.19, and 0.92, respectively). Conversely, Scomber japonicus and Scomber scombrus showed the highest prevalence (74.07% and 68.00%, respectively) and mean abundance (188.24 and 249.82, respectively). The data suggest that the coastal area of the Karaburun Peninsula (southern Albania) may be a high-risk area for zoonotic diseases, and the consumption of raw or undercooked fish caught in the Vlora district could result in the acquisition of human anisakiasis. For these reasons, it is necessary to improve the surveillance plan.

scholarly journals An updated list of monogenoidea from marine fishes of Vietnam

2020 ◽  
Vol 42 (2) ◽  
Author(s):  
Nguyen Manh Hung ◽  
Nguyen Van Ha ◽  
Ha Duy Ngo
Keyword(s):  
Marine Fish ◽  
Fish Species ◽  
Classification System ◽  
Taxonomic Status ◽  
Marine Fishes ◽  
Marine Fish Species ◽  
Monogenean Species ◽  
System A ◽  
Current Classification ◽  
Current Classification System

In this paper, we updated the list of monogenean species from marine fishes of Vietnam. Taxonomic position of monogenean species were arranged according to the current classification system. A total of 220 monogenean species from 152 marine fish species were listed. Distribution, hosts and references of each species were given. In addition, amendations of taxonomic status of taxa were also updated.  

scholarly journals Growth pattern of three species of Mullets (Pisces: Mugilidae) in Sombreior River, Rivers State, Niger Delta, Nigeria

2020 ◽  
Vol 5 (2) ◽  
pp. 68-72 ◽  
Author(s):  
Henry Eyina Dienye ◽  
Olaniyi Alaba Olopade
Keyword(s):  
Fish Species ◽  
Growth Pattern ◽  
Niger Delta ◽  
Condition Factor ◽  
Well Being ◽  
Biological Information ◽  
Allometric Growth ◽  
Good State ◽  
Abiotic And Biotic Factors ◽  
Rivers State

Length-weight relationships (LWRs) and condition factor are important biological information to assess the growth pattern and wellbeing of fish species influenced by numerous abiotic and biotic factors. To date, no data on the LWRs and condition of mullets in Sombreior River, Niger Delta. Hence, this research was conducted to determine abundance, length–weight relationship and Fulton’s condition factor (K) of three species of fish belonging to family Mugilidae in Sombreior River, Nigeria. There were a total of 248 samples from five sampling stations for a period of months. Fish species were of various sizes ranging from 24.66±0.40 to 26.35±0.26cm in length and 141.41±6.30 to 161.56±5.87g in weight. For the three species, slope (b) values ranged from 2.18 to 2.68 indicating a negative allometric growth of all fish species. The mean condition factor ranged from 0.89±0.03 forsix Mugil cephalus to 0.93±0.03 for Parachelon grandisquamis while the coefficients of determination (R2) of the LWR regressions ranged between 0.64 (Neochelon falcipinnis) and 0.79 (Parachelon grandisquamis). It was concluded that the mullets in the Sombreior River had a negative allometric growth pattern and the condition is showing the species were in good state of well-being since mean K values are  greater than 1.

scholarly journals Thermal bottlenecks in the life cycle define climate vulnerability of fish

Science ◽  
2020 ◽  
Vol 369 (6499) ◽  
pp. 65-70 ◽  
Author(s):  
Flemming T. Dahlke ◽  
Sylke Wohlrab ◽  
Martin Butzin ◽  
Hans-Otto Pörtner
Keyword(s):  
Life Cycle ◽  
Fish Species ◽  
Thermal Tolerance ◽  
Thermal Adaptation ◽  
Inverse Correlation ◽  
Climate Projections ◽  
Temperature Sensitive ◽  
Life Stages ◽  
Ontogenetic Changes ◽  
Species Vulnerability

Species’ vulnerability to climate change depends on the most temperature-sensitive life stages, but for major animal groups such as fish, life cycle bottlenecks are often not clearly defined. We used observational, experimental, and phylogenetic data to assess stage-specific thermal tolerance metrics for 694 marine and freshwater fish species from all climate zones. Our analysis shows that spawning adults and embryos consistently have narrower tolerance ranges than larvae and nonreproductive adults and are most vulnerable to climate warming. The sequence of stage-specific thermal tolerance corresponds with the oxygen-limitation hypothesis, suggesting a mechanistic link between ontogenetic changes in cardiorespiratory (aerobic) capacity and tolerance to temperature extremes. A logarithmic inverse correlation between the temperature dependence of physiological rates (development and oxygen consumption) and thermal tolerance range is proposed to reflect a fundamental, energetic trade-off in thermal adaptation. Scenario-based climate projections considering the most critical life stages (spawners and embryos) clearly identify the temperature requirements for reproduction as a critical bottleneck in the life cycle of fish. By 2100, depending on the Shared Socioeconomic Pathway (SSP) scenario followed, the percentages of species potentially affected by water temperatures exceeding their tolerance limit for reproduction range from ~10% (SSP 1–1.9) to ~60% (SSP 5–8.5). Efforts to meet ambitious climate targets (SSP 1–1.9) could therefore benefit many fish species and people who depend on healthy fish stocks.

scholarly journals Strong Effects of Temperature on the Early Life Stages of a Cold Stenothermal Fish Species, Brown Trout (Salmo trutta L.)

PLoS ONE ◽  
2016 ◽  
Vol 11 (5) ◽  
pp. e0155487 ◽  
Author(s):  
Emilie Réalis-Doyelle ◽  
Alain Pasquet ◽  
Daniel De Charleroy ◽  
Pascal Fontaine ◽  
Fabrice Teletchea
Keyword(s):  
Brown Trout ◽  
Fish Species ◽  
Early Life ◽  
Salmo Trutta ◽  
Life Stages ◽  
Early Life Stages ◽  
Brown Trout Salmo Trutta ◽  
Effects Of Temperature

The early life stages of an estuarine fish, the red drum (Sciaenops ocellatus), are tolerant to high pCO2

2017 ◽  
Vol 74 (4) ◽  
pp. 1042-1050 ◽  
Author(s):  
Joshua Lonthair ◽  
Rasmus Ern ◽  
Andrew J. Esbaugh
Keyword(s):  
Heart Rate ◽  
Fish Species ◽  
Early Life ◽  
Red Drum ◽  
Sciaenops Ocellatus ◽  
High Pco2 ◽  
Estuarine Fish ◽  
Life Stages ◽  
Early Life Stages ◽  
Estuarine Species

Ocean acidification (OA) and other climate change induced environmental alterations are resulting in unprecedented rates of environmental deterioration. This environmental change is generally thought to be too fast for adaptation using typical evolutionary processes, and thus sensitivity may be dependent on the presence of existing tolerant genotypes and species. Estuaries undergo natural pCO2 fluctuations over a variety of time scales, and levels regularly exceed the predicted end of the century values. Interestingly, estuarine fish species have been overlooked in reference to the impacts of OA. Here, we use the estuarine red drum (Sciaenops ocellatus) as a model to explore the hypothesis that early life stages of estuarine species have intrinsic tolerance to elevated pCO2. Our sensitivity endpoints included: survival, growth, yolk consumption, heart rate, and scototaxis. Survival was significantly decreased when exposed to 1300 μatm and 3000 μatm, and coincided with a significant increase in heart rate at the 3000 μatm exposure. However, these effects were less pronounced than the findings of previous studies on other marine fish species. Yolk depletion rate and standard length were not significantly affected by pCO2. Scototaxis behaviour was also not significantly affected by exposure to elevated levels of pCO2 under both acute and acclimated exposure scenarios. Overall, these results support the hypothesis that estuarine life history and habitat usage may play a critical role in determining sensitivity of fish species to OA. Furthermore, estuarine species may provide present-day insight into the physiological and ecological foundation of OA tolerance.

Viral erythrocytic necrosis in fish: a review

1982 ◽  
Vol 81 (3) ◽  
pp. 169-176 ◽  
Author(s):  
D. A. Smail
Keyword(s):  
Electron Microscopy ◽  
Fish Species ◽  
Blood Parameters ◽  
Infected Fish ◽  
Fish Populations ◽  
Infection Prevalence ◽  
Wild Populations ◽  
Cytoplasmic Inclusions ◽  
Virus Morphology

SynopsisViral erythrocytic necrosis (VEN) in fish is prevalent in a wide variety offish species. It has been detected in both wild and captive fish populations. The infection prevalence in wild populations of some fish species is correlated inversely with the age of the fish. VEN is characterised by cytoplasmic inclusions in circulating erythrocytes of infected fish; nuclear necrosis of erythrocytes may also be evident by light microscopy. The stage and degree of infection affect the type of cytology seen in VEN infections of different fish species. By electron microscopy, infected erythrocytes show spherical virions within the cytoplasm and the virion size is characteristic of the host erythrocytes infected. To date, knowledge of VEN viruses in fish is restricted to virus morphology and propagation in vivo, although preliminary studies have indicated the type of blood parameters which VEN can affect. No such virus has been fully isolated and characterised and all of Koch's postulates have not been fulfilled.

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