Fish Collection Research Articles

Morphology and Reproductive Biology of Blue Perch Badis assamensis Ahl 1937 Recorded From a Hill Stream in Assam, India

ABSTRACTA badid, Badis assamensis Ahl, 1937, was recorded for the first time from the intermediate zone of a semi‐torrential stream called Basistha in Assam, which is a small tributary of the river Brahmaputra. The fish species Badis assamensis is currently listed in the data deficient (DD) category of IUCN. The species has previously been reported in swampy wetlands in the upper reaches of the Brahmaputra valley in Assam; with no detail description on its biology however. The current work redescribes morphology and presents detail reproductive biology of this species based on fresh collection of 377 individuals from the Basistha. length‐weight relationships (LWR) analysed in this species indicated an isometric growth; and condition factor (K) indicated a suitable habitat for this species. Badis assamensis exhibits a non‐seasonal breeding behaviour twice a year, as analysed from the Gonado‐somatic and ovarian indices. During certain period of the year, local people use unscientific ways of fish collection thereby resulting in a steep decline in fish population. The study is believed to lay an insight into this species' geographical range from a swampy wetland habitat in upper reaches of the Brahmaputra basin; to a semi‐torrential hill stream habitat in the lower Brahmaputra sub‐basin; thereby providing baseline information on this DD species. Analysis of morphometric and reproductive parameters of this species not reported earlier is the major highlight of the present study.

Updated Fish Fauna of Karpuz and Ilıca Streams in Antalya Region: Species Diversity and Ecological Assessment

This research aims to provide an updated account of the fish fauna present in the streams Karpuzçay and Ilıca located in Antalya, southwestern Türkiye. The research was conducted through fish sampling at four strategically selected stations within these rivers, which were chosen for their high representativeness of the overall riverine ecosystem. The sampling took place in May 2023, primarily using the SAMUS 1000 portable electrofishing device to collect fish specimens. Records from Ege University Faculty of Fisheries Freshwater Fish Collection (EFSM), and the Zoological Collection of Recep Tayyip Erdoğan University (FFR) were also included in the study, along with published literature, to create an updated fish list for these two rivers. Our findings revealed the presence of multiple families, indicating a diverse fish community within these freshwater systems. Significantly, this study reports the presence of Tinca tinca (tench) in Karpuzçay Stream for the first time according to EFSM records, marking a noteworthy addition to the known fish fauna of the region. Karpuzçay and Ilıca rivers are critical components of the Antalya River Basin, contributing substantially to the area's ecological balance, economic activities, and cultural heritage. These rivers support a variety of aquatic and riparian habitats, which are essential for numerous species and local communities. Despite their importance, the rivers face numerous threats including pollution, habitat destruction, water extraction for agriculture, and the impacts of climate change. These pressures underscore the urgent need for effective conservation measures to safeguard the integrity and biodiversity of these river systems. This study not only updates the fish species list of the Karpuzçay and Ilıca rivers but also discusses the implications of these findings for the health and conservation of these aquatic ecosystems. By compiling and analyzing existing information alongside new data, I aim to provide a comprehensive overview of the rivers' biodiversity and the environmental factors influencing it. The discussion includes recommendations for conservation strategies to mitigate threats and promote the sustainable management of these vital freshwater resources.

Emergence of black spot syndrome in Caribbean reefs: a century of fish collections reveal long-term increases in Scaphanocephalus infection.

Despite evidence that certain diseases of marine wildlife are increasing, long-term infection data are often lacking. Archived samples of hosts from natural history collections offer a powerful tool for evaluating temporal changes in parasitism. Using vouchered fish collections from the Southern Caribbean, we investigated long-term (1905-2022) shifts in infections by the trematode Scaphanocephalus spp., which causes black spot syndrome (BSS) in reef fishes. Examination of 190 museum-preserved fishes from Curaçao and Bonaire revealed that Scaphanocephalus infections are not new, with histologically confirmed detections from as early as 1948. However, Scaphanocephalus was rare among archival surgeonfish and parrotfishes, with an infection prevalence of <10% and an average abundance of 0.25 metacercariae per fish. Contemporary collections of 258 ocean surgeonfish and parrotfishes (7 species) supported a 7-fold higher prevalence (71%) and a 49-fold higher abundance (12.1). These findings offer evidence that infections by Scaphanocephalus spp. have increased substantially over the past century and underscore the value of biological repositories in the study of emerging parasites within marine ecosystems. We emphasize the need for additional research to evaluate the geographical extent of BSS emergence, test proposed hypotheses related to shifts in host density or environmental characteristics and assess the consequences for affected species.

Diversity of fish otoliths from the Gulf of Mexico and the Caribbean Sea: Report on the first digital collection of fish otoliths (Actinopterygii) from the Atlantic region of Mexico

The Otolith Collection of Fishes from the Gulf of Mexico and Caribbean Sea was created with the objective to conserve and illustrate the diversity of these structures from species living in the Gulf of Mexico, the Caribbean Sea, and the freshwater and brackish systems of the Yucatan Peninsula, incorporating morphological descriptions and morphometric data. Otoliths, non-skeletal calcareous structures that develop in the inner ear of fish, are essential for balance and hearing. They have become pivotal tools for age and growth determination, population analysis, and ecological, trophic, and archaeological studies due to their resistance to degradation and the extensive information they provide about the environment and physiology of fish. The collection now includes otoliths from 214 species, representing 67 families, obtained through sampling campaigns and collaborations with local fishermen. The otoliths are extracted using techniques that ensure the integrity of the structures for later preservation. High-resolution images were obtained using optical and scanning electron microscopy, and these images are stored in an online database. This database facilitates research and teaching by providing public access to digital specimens and associated data. In addition to fostering academic development, this collection represents a significant step towards the creation of a national platform for otolith data analysis, aligned with international efforts to digitize biological collections. Despite the financial and logistical challenges involved in building and maintaining biological collections, this collection demonstrates its value as an essential resource for taxonomic, systematic, and ecological studies, as well as for biodiversity education and awareness. The online availability of the collection not only facilitates access to data but also promotes innovation and international collaboration in the study of fishes and their habitats.

Fish Distribution Pattern and Management in the Tinau River, Palpa

For study direct observation, survey, questionnaire, interviews and discussion method are used to meet the objectives. The main objectives of the study were fish distribution pattern and fish management. The field work was performed between September 2016 to june 2017 of different five stations in Tinau river. Local fishermen were also used for the collection of fishes from sampling sites. Cast net, hook, Bhureli jal and Nets (Jhal) other locally available devices were used for the collection of fish sample. Altogether 5 orders, 9 families, 14 genera and 25 species were found in the study area. Among them 19 fish species from Station I, 16 fish Species from Station II and station III, 10 fish species from Station IV and 7 species from Station V were collected with the help of local fisherman. Fish species such as Channa punctatus, Puntius conchonius and Glyptothorax pectinopterus were found to be clumped in distribution while the rest of the fishes were uniformly distributed. Cyprinids were found to be the most common and dominant among all the species. The human impacts like construction of dam, bridges, riverbed extraction, bank erosion, illegal fishing and use of poisonous chemicals effects on the fish distribution and management directly of the Tinau river. For the management practices like implementation of strict rules and regulations, made ladder for fish passing, construction of fish barrier, plantation, control water pollution and awareness programmes should be done with the help of local people and other institutions. This study helps the local people to pay more attention towards the knowledge about indigenous or locally found fishes and proper management of the Tinau river.

Evaluation of Praziquantel effectiveness in treating Nile tilapia clinostomid infections and its relationships to fish health and water quality

This study aimed to conduct a multidisciplinary investigation integrating detailed morphology, molecular characterization, water parameters, histopathology alteration, and the trials of treatment of Clinostomum spp. In this study, 300 Nile tilapia (Oreochromis niloticus) were collected from the farmed and wild Nile River at Al Bahr Al Aazam, Giza Governorate to assess Clinostomid infection prevalence. Fish and water samples were collected from private fish farms, and water drains at Dakahlia, and Giza, Egypt. Analysis of the water revealed inadequate water quality, particularly in the fish farms. Snails and piscivorous birds were abundant at fish collection sites. The recovered Clinostomid MCs morphological characteristics and COI gene sequence analysis identified them as Clinostomum complanatum, C. phalacrocoracis, and Euclinostomum heterostomum. Clinostomid MCs disturbed the fish’s hematological and biochemical blood parameters. Bath treatment of parasitized fish with praziquantel (2 mg/L for 24 h) revealed a significant reduction in the number of vital MCs vs. infected fish (non-treated). Praziquantel (PZQ) is an effective and safe therapy for controlling Clinostomid infections affecting farmed Nile tilapia. The current findings indicate a link between poor environmental conditions and Clinostomum infections in tilapia. The study highlights the impacts of Clinostomid MCs on fish health and recommends bath treatment with PZQ as an efficient control method for these dangerous parasites to protect human and fish health.

Distinct food-web transfers of 137Cs to fish in river and lake ecosystems: A case study focusing on masu salmon in the Fukushima evacuation zone

This study was conducted to elucidate the spatial and size variations, and food-web transfer of 137Cs in freshwater fish in the upper reaches of the Ukedo River system, a highly contaminated river system flowing through the Fukushima evacuation zone. Fish collection and environmental surveys were conducted in the summer of 2020 at five forest rivers and at the Ogaki Dam reservoir (an artificial lake) with different air dose rates (mean 0.20–3.32 μSv/h). From the river sites, two salmonid species (masu salmon and white-spotted charr) were sampled, with masu salmon generally exhibiting higher 137Cs concentrations, ranging widely (10.6 Bq/kg-wet to 13.0 kBq/kg-wet) depending on the fish size (size effect) and site. The 137Cs concentrations in masu salmon were explained by the air dose rates, 137Cs concentrations in water, sediments (excluding the lake site), and primary producers, with site-specific variations. In the rivers, masu salmon (fluvial type with parr marks) mainly fed on terrestrial insects with higher 137Cs concentrations compared with those of aquatic insects, indicating that 137Cs was transferred mainly to fish through the allochthonous forest food-web during summer. In the lake, masu salmon (lake-run type with larger size and silvery body coloration) mainly preyed on smaller fish with lower 137Cs concentrations, demonstrating that 137Cs is transferred to fish through the autochthonous lake food-web with biomagnification. Differences in 137Cs concentrations among masu salmon (mean 441 Bq/kg-wet) and other fish species (mean 74.8 Bq/kg-wet to 2.35 kBq/kg-wet) were also found in the lake. The distinct 137Cs transfers to river and lake fish were supported by stable isotope analysis: δ15N and δ13C values enriched stepwisely through the food-webs were, respectively, higher and lower in the lake. Our results obtained using multiple approaches clearly revealed the distinct food-web transfer of 137Cs in river and lake ecosystems. These findings can contribute to prediction of radioactive contamination in freshwater fish in the Fukushima evacuation zone.

Diversity, functional redundancy, and vulnerability of reef fish communities of the Saudi Arabian coast, in the northern Red Sea

In light of the current development of several giga-projects along the Saudi Red Sea coast, understanding the health status of coral reefs is paramount to developing baselines and management strategies to minimize the human impact on these ecosystems. Here, we present an assessment of the diversity, functional redundancy, and vulnerability for coral reef fish communities in the northern Red Sea. The focus area of our study falls within the marine jurisdiction of the NEOM giga-project. We performed fish surveys with three different methods aiming to cover a wide set of habitats and thus capture a comprehensive picture of the regional diversity: i) standardized belt transects, ii) roving diviersity surveys, and iii) collection of cryptobenthic fish. Our results showed a highly variable community composition along the ten surveyed sites highlighting Sindalah as an essential site for piscivore species, Al Muwaileh as an important site for herbivores, and Sanafir-Tiran as the most diverse site. Functional diversity analysis revealed similar levels of redundancy, over-redundancy, and vulnerability among sites. Functional richness, evenness, and divergence did not vary substantially between sites and, in general, indicated that the fish communities in the selected sites present mid to low levels of functional diversity. We further compare regional-scale and site-specific functional assessments. Notably, some of the species groups that are functionally redundant at the regional scale represented vulnerable functions at the site level. These results call to attention the need to create site-specific conservation strategies and not to solely rely on regional diviersity assessments as the basis for management decisions.

A historical Llewellyn Ivor Price fossil fish collection from the Middle to Late Miocene of the Brazilian Amazon

Brazilian Miocene fluvial and lacustrine deposits are mainly found in the southwestern Amazon basin in the state of Acre, where fossiliferous sections from the Middle to Late Miocene of the Solimões Formation (Fm.) emerge in riverbanks during the dry season and low river-water level periods. The Solimões Fm. is notable for its high fossil vertebrate diversity (Myliobatiformes, Siluriformes, Ceratodontiformes, Osteoglossiformes, Characiformes, Acregoliathidae, Squamata, Crocodilia, Testudines, Suliformes, Rodentia, Notoungulata, Litopterna, Astrapotheria, Proboscidea, Didelphimorphia, Pilosa, Sirenia, Cetacea, Primates, Chiroptera, and Artiodactyla) deposited in the paleo-Amazon context. This fossiliferous faunal assemblage reflects the major geological and paleoclimatic Miocene/Pliocene transition events that triggered the greatest extinction of megafauna and other groups of animals in the Paleo-Amazon and, alongside the establishment of the largest Amazon transcontinental river in South America, led to species turnover and the diversity explosion to current levels. Paleontological expeditions carried out between 1950s and 1970s at Solimões Fm. outcrops along the Acre and Upper Juruá rivers allowed the recovery of an extraordinary vertebrate paleontological collection, albeit published in fragmentary contributions. Despite supporting the largest continental fish fauna, comprising ca. 2400 valid extant species, the Amazon hydrographic system harbors a still poorly known fossil ichthyofauna. This study describes a fossil fish assemblage from the Solimões Fm. for the first time based on high accuracy data acquired by improved microCT techniques, computerized systems, and examinations of the best recent and fossil fish collections. This fish assemblage is employed to elucidate ancestral Amazonian fauna paleodiversity and paleoenvironmental context interpretations and explore the elements that led to coeval paleo-ichthyofauna from the northwestern paleo-Amazon region. Miocene species Phractocephalus (†P. acreornatus and †P. nassi) are proposed as fossil guides.

Two new species of the armored catfish genus Panaqolus (Siluriformes, Loricariidae) from the Ecuadorian Amazon.

Currently four described species of genus Panaqolus have been reported from the Amazon River basin in Ecuador: P. albomaculatus (Kanazawa 1958), P. dentex (Günther 1868), P. gnomus (Schaefer & Stewart 1993) and P. nocturnus (Schaefer & Stewart 1993). Revision of specimens deposited at the fish collection of Museo de la Escuela Politécnica Nacional (MEPN), Quito, indicated the presence of two additional species, both new to science: P. orcesi n. sp. and P. pantostiktos n. sp. The new species are similar to each other, and to P. albomaculatus and P. nix Cramer & Rapp Py-Daniel 2015 in having the head, body, and fins covered with light dots. Diagnostic characters comprise differences in color pattern, including size and density of light dots on head, body, and fins; as well as various morphometric characters. Apparently, both new species reach larger sizes than previously described species of Panaqolus. The two new species can be included in the subgenus Panafilus (Lujan et al. 2017); they come from the Tigre and Napo River basins, two isolated tributaries in the western Amazon.

An updated survey of freshwater fishes within Letchworth State Park and surrounding area's of the Genesee River.

The goal of this study was to gather information about freshwater fishes in Letchworth State Park (42.615275° N, -77.992825° W), a portion of New York State-owned land located in the Genesee River Watershed that lacks known data about its fish diversity. Fish collection took place between 2017 and 2019 in the Genesse River upstream and downstream of the falls using electrofishing, gill, hoop, and seine netting. This was the first attempt at a comprehensive survey of this portion of the river, which allowed for a baseline to be established regarding fish biodiversity in the region. The updated total number of species found in this portion of the Genesee River was 25, 22 of which were newly identified downstream of the falls in Letchworth State Park. We encourage further collection and continuation of this survey with consistent sampling techniques to raise awareness about the importance of freshwater fish diversity in stream ecosystems across the globe.

Establishing a fish repository at Ege University Faculty of Fisheries (1965-2023): A Journey on a long and challenging road to becoming a museum

This study examined preserved marine fish specimens collected from numerous field surveys conducted along Türkiye’s Black Sea, Marmara, Aegean, and Mediterranean coasts since 1965. Our review and categorization of these materials revealed that the specimens belong to 360 species from 131 families. Current data shows that the museum collection includes 20 species of cartilaginous fish and 8 species of bony fish listed as endangered on the IUCN Red List, alongside 54 non-native fish species. Prepared according to museum standards by Ege University Fisheries Faculty’s Scientific Material (ESFM), this collection of Turkish marine fish constitutes 66% of all Turkish marine fish fauna. This makes it the largest and oldest marine fish collection in Türkiye. Considering Türkiye’s maritime borders with neighboring countries, this collection is significant nationally and globally. Given the diverse marine fish species in Turkish seas over the past half-century, this preserved material is a vital reference for local and foreign ichthyologists. If organized and transformed into a visitable museum, this extensive collection could raise awareness about the diversity of marine fish species in our seas. As a result, we have established the ” biological repository of Turkish Marine Fish Department” in the Faculty Museum, now known as the Fisheries Faculty’s Scientific Material (ESFM) at Ege University. We present the fish in the collection as a species list.

At-sea application of the comet assay to a deep-sea fish

Given the go ahead, deep-sea mining operations are likely to continue for decades on a substantial spatial scale and the resulting sediment plumes combined, are likely to extend beyond the licenced mining areas, and could lead to the chronic exposure of deep-sea organisms to a mixture of metals, even mobile species, such as fish, that could conceivably display avoidance behaviour. The metal concentrations, often substantially below lethal doses, mean that individual mortality is too blunt a measure to allow assessment of “serious harm”. Commonly used cellular biomarkers of exposure in ecotoxicology include DNA damage using the Comet assay. True deep-sea ecotoxicological studies with fish are rare and to our knowledge, there are no published data or method optimizations for deep-sea fish. Coryphaenoides ssp. were collected during SMARTEX expedition 1 (Feb/Mar, 2023) to the Clarion Clipperton Zone (CCZ) in the Eastern Pacific Ocean using a baited trap deployed between 4580–4,732m depth for 24–48 h. Blood and gill tissue were removed and processed for the Comet assay. In order to reduce artefactual DNA damage from cryopreservation observed previously, two sets of samples were prepared: a cryopreservative (10% DMSO) was added to one set of samples and stored at −80 °C; the second set was used to perform a Comet assay within hours of collection. A custom-built gimble table enabled horizontal electrophoresis at sea after which Comet assay slides were dried and stored at room temperature until further analysis. The Comet assay was also assessed in freshly sampled and frozen rainbow trout cells as a proxy control in order to evaluate potential artefacts from the collection and sampling procedure of the deep-sea fish. The blood samples processed at sea had a significantly reduced level of DNA damage compared to the frozen samples. There was no significant difference between the fresh deep-sea and rainbow trout samples. However, the freshly prepared gill samples in Coryphaenoides ssp. showed substantial artefacts, possibly as a consequence of barotrauma. These results represent the first effort at establishing baseline DNA damage data for deep-sea fish, an essential component in understating and quantifying the impact of deep-sea mining.

A Comparison of Methods of Visual Census and Cryptobenthic Fish Collecting, an Integrative Approach to the Qualitative and Quantitative Composition of the Mediterranean Temperate Reef Fish Assemblages

The present research quantitatively compared the fish composition among two methods for non-cryptic benthic fish species and one method for cryptobenthic fish species for the first time for the Mediterranean temperate reef fish assemblage. A visual census of fishes was performed within a cylinder of 4 m radius and within a cylinder of 2 m radius, while the cryptobenthic fishes were collected using a square of 1 m2 with anesthetic. The data and material were collected at fifty sampling points. The visual census methods together recorded 31 species, and the square with anesthetic method recorded 18 species. The quantitative comparison of methods of visual census and cryptobenthic fish collecting showed significantly different species richness, total fish abundance, and fish assemblage structure among methods. The applied methods were highly complementary. The cylinder of 2 m radius is well suited for epibenthic fishes and the cylinder of 4 m radius is reliable for hyperbenthic and benthopelagic fishes. Therefore, each of the methods well covered one of three components of ichthyobenthos (hyperbenthic, epibenthic, and cryptobenthic fishes), and all three methods together provided a far more complete assessment of fish species composition than any individual census method for the Mediterranean littoral benthic fishes.

Web-Based Integration of IoT and Artificial Intelligence for Monitoring Aquariums

Technology is now an indispensable part of work across all fields and locations. For instance, in fish cultivation and among ornamental fish enthusiasts, technology plays a pivotal role in regulating and notifying when ornamental fish's environmental conditions require attention. This includes monitoring and alerting for cleaning or feeding needs. Ornamental fish are particularly sensitive, often carrying a higher price tag. Due to their susceptibility to stress and their relatively costly nature, those involved in ornamental fish cultivation and collection frequently face significant losses. These losses can occur when fish are collected, raised, and fall ill or, in the worst-case scenario, die. In response to these challenges, technological innovations have emerged to simplify the monitoring of ornamental fish's environmental conditions. This is achieved through IoT-based solutions accessible anytime and anywhere via the web. These innovations incorporate three primary sensors: pH sensors, clarity sensors, and temperature sensors. Additionally, Thingsboard is used to facilitate real-time monitoring of sensor data. These aquarium monitoring systems for ornamental fish hold the potential to enhance fish welfare and health, mitigate risks, and provide hobbyists and professionals with a more effective and informed experience in maintaining ornamental fish. However, it's important to note that the success of this system relies heavily on the quality of hardware, meticulous software development, and a profound understanding of the specific needs of ornamental fish

Environmental correlates with fish assemblage change and biotic homogenization across 40 years in an Ozark, Gravel‐Bed river basin

AbstractFish assemblages in freshwater ecosystems are becoming more homogenous from multiple abiotic, environmental, and physicochemical variables at different scales. Historical fish collections (1976–1977) by Billy Michael Johnson and Dr. Johnson K. Beadles were compared to contemporary fish collections (2018–2019) in tributaries of the Eleven Point River basin in Arkansas to examine patterns of fish assemblage change. Fish assemblage change variables were compared to pasture land use/land cover (LULC) at multiple scales and in‐stream habitat variables to understand relationships and discover potential correlates suggesting biotic homogenization. Fish assemblages in the Eleven Point River basin of Arkansas have experienced significant spatiotemporal changes, and LULC change and habitat alterations may have influenced this process. Increased tolerant species and decreased intolerant species at sites contributed to biotic homogenization, particularly in pool habitats. Surprisingly, expansion of some intolerant fishes was also observed that tend to occupy riffles. Sites with high percentages of pasture LULC at finer spatial scales typically had more homogenised fish assemblages. We hypothesized gravel aggradation from local pasture land use has degraded pools and increased riffle habitat, resulting in homogenised fish assemblages in the Eleven Point River basin over the study period. Few studies link LULC, in‐stream habitat, and biotic homogenization when examining fish assemblage change over time, and these dynamics can be particularly complex in upland streams experiencing gravel aggradation. Similar research in other upland, gravel‐bed river systems would provide a broad understanding of the presented environmental associations.

Is Garra rezai (Teleostei, Cyprinidae) a species known only from two widely disjunct areas in the Tigris drainage?

Garra rezai was recently described from two geographically distant areas in the Tigris drainage: upper Yanarsu River (eastern Türkiye) and Bouein-Sofla Creek (Iran). In the scope of this study, we aimed to ascertain the distribution ranges of G. rezai and its morphologically most similar congener G. rufa in Türkiye by examining 1165 specimens from 73 lots, which were collected between 1957 and 2023 and currently curated in two broad fish collections. To achieve this, we focused on two important diagnostic morphological characters which distinguish these two species: scales on predorsal mid-line between dorsal-fin origin and nape, and branched dorsal-fin rays. The results revealed that G. rufa is a widely distributed species in the Tigris-Euphrates catchment, while G. rezai is regionally widespread, with populations identified in at least six different regions within the Tigris catchment. Additionally, G. rezai is documented for the first time in the upper Euphrates. Furthermore, we identified the drainage areas where G. rezai co-exists with G. rufa.

Hematological, biochemical and oxidative responses induced by thermal shock in juvenile Tambaqui (Colossoma macropomum) and its hybrid Tambatinga (Colossoma macropomum x Piaractus brachypomus).

The effects of thermal shock on hematological, biochemical and antioxidant responses were evaluated in liver tissue of juvenile tambaqui (Colossoma macropomum) and tambatinga (♀ C. macropomum × ♂ Piaractus brachypomus). Forty juveniles of tambaqui and 40 juveniles of tambatinga, of the same age and with an initial weight of 23.3 ± 6.7g, were randomly distributed in eight 28L circular tanks. A tank (n = 10 fish) of tambaqui and a tank (n = 10 fish) of tambatinga were then used to obtain basal data. The other animals were subjected to thermal shock with sudden temperature reduction from 28 to 18 ºC. Blood and tissue were then collected after 1, 6 and 24h from the onset of thermal shock. No mortality was observed during the experimental period. Thermal shock increased triglyceride levels after 24h of stress for tambaqui and reduced values for tambatinga. There was an effect on plasma glucose only for fish group (P < 0.0001) and collection time (P < 0.0001) with a peak observed for the hybrid after 6h. The interaction of factors for SOD indicated greater activity for tambatinga at the 6h collection and lower at basal and 1h collections. There was an interaction for CAT (P = 0.0020) with less activity for tambatinga at 1h. However, thermal shock and hybridization did not influence GST and TBARS levels in liver tissue. Therefore, the results suggest that the hybrid, tambatinga, is more efficient at promoting adjustments of biochemical responses and antioxidant enzymes during thermal shock.

Parasitism and branchitis in various fish species from 4 Cook County, Illinois inland freshwater lakes, 5-year survey, 2017-2021.

We investigated disease trends of concern for fish or public health in a 5-y (2017-2021) prospective survey of fish in Cook County, IL, inland lakes. Lesions were assessed in relation to fish species, lake type and location, season and collection year, and lake water chemistry parameters. Fish included bullheads (n = 98), common carp (n = 99), bluegill (n = 114), and largemouth bass (n = 118). Annually, fish collection and point-source water sampling were conducted in spring, summer, and fall from both seepage and impoundment lakes. Examinations included autopsy, wet-mount cytologic assessment for ectoparasites, and histopathology. No lesions of public health concern were detected. The most common abnormalities were branchitis (261 of 429; 60.8%) and endoparasitism (312 of 429; 72.7%). Branchitis was mild in most cases (189 of 261; 72.4%) and concurrent with branchial parasitism in 175 of 261 (67%) cases. Monogeneans were the most common gill parasites but did not influence branchitis severity (Kruskal-Wallis, p = 0.484). Using generalized ordered logistic regression, predictors of branchitis severity included fish species (p < 0.001), the interaction of lake or location and alkalinity (p < 0.001), and water temperature or season (p < 0.001). Endoparasites included tissue larval trematodes (metacercaria), nematodes, and cestodes (plerocercoids), enteric acanthocephalans, gastric trematodes, renal myxosporidia, biliary and gall bladder myxosporidia, enteric cestodes, and tissue microsporidia. Using generalized ordered logistic regression, variables influencing endoparasitism severity included species (p < 0.001), year (p < 0.001), chloride level (p = 0.009), and the interaction of year and chloride level (p < 0.001). Our results suggested overall good health of fish in sampled Cook County inland lakes and provide a foundation for continued monitoring of ecosystem and public health in the urban environment.

Catching Dory: selling aquarium fish supports coastal livelihoods in Indonesia

The global marine aquarium trade has created new local markets across the planet, including in Indonesia, now the second-largest exporting country of marine aquarium fish in the world. Participating in the global aquarium trade has been touted as a potentially sustainable addition to fisher livelihoods, but scant data exist showing the numbers of fish coming off the reef and how those fish contribute to income. To determine how participants in the trade incorporate aquarium species in their livelihoods, we examine source-level aquarium fish collecting and trading data in the Banggai Archipelago, a region in Central Sulawesi that has become a significant source for popular aquarium, also known as ornamental, fish species. Using a sustainable livelihoods lens, we examine this data to understand how participants in the aquarium trade both contribute to as well as benefit from the trade and consider how their participation relates to emerging Blue Justice principles. From one year of buying and selling data at the fisher, intermediary buyer, and regional trader levels, we show that catching and selling fish for the aquarium trade represents an average of nearly 20% of their gross annual income and provides added diversity and flexibility to fisher and trader livelihoods in the region, especially during seasons of rough weather. We suggest that managers of an impending marine protected area in the region would do well to consider how to sustain these livelihood benefits.