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In the present study, we describe and compare the diet of two populations of Pleurodema diplolister from northeastern Brazil. We assessed whether diet composition varies between the different populations and whether the size of individuals is related to the composition, volume and the size of prey consumed. Stomach contents were retrieved through the stomach-flushing technique from specimens collected in two municipalities (Morro do Chapéu and Rio de Contas) in the semi-arid region of Bahia State. We captured a total of 163 individuals and 91 of them had some type of stomach contents. A total of 278 food items were classified and distributed among 10 prey categories. The main food items consumed include Hymenoptera (Formicidae), Isoptera and Coleoptera. The morphometric measurements (snout-vent length and mouth width) of P. diplolister were significantly correlated with the diet (total volume of prey and length of the largest prey ingested). Diet composition differed between the two localities, showing little overlap between populations. Part of the variation in diet composition may be attributed to differences in the size of P. diplolister individuals. However, many factors can be associated to these differences, such as prey availability, landscape structure or even anthropic influences on the local ecosystem. In order to unravel the intricacies behind these distinct patterns, a comprehensive examination of these factors and others becomes imperative. This detailed analysis is crucial for a more thorough understanding of the extent to which these elements influence the feeding habits of anurans. [ABSTRACT FROM AUTHOR]

Macrobrachium amazonicum (Heller, 1862) is a freshwater prawn species subject to high commercial exploitation in northern Brazil, with wide geographic distribution and high phenotypic plasticity. This study aimed to assess the natural diet of an M. amazonicum population from Rio Grande, comparing consumed items with differences according to sex, seasons, and habitat food availability. The prawns were collected monthly between September 2018 and August 2019. A total of 348 stomachs were examined, and their content evaluated based on degree of repletion, the point method, and frequency of occurrence. Food preferences were also determined. Seven food types were recorded in the stomachs of M. amazonicum, including microplastics. No significant differences were observed in the diet between males and females or across different seasons. The species exhibited no food preference in its diet. The findings confirm an omnivorous diet for M. amazonicum and suggest that the composition and proportion of dietary items may depend on their availability in the environment. The presence of microplastics in the analyzed stomachs raises concern as it indicates contamination in the aquatic environment resulting from unsustainable human activities. [ABSTRACT FROM AUTHOR]

Melolonthinae represent a megadiverse assemblage of scarab beetles, exhibiting dramatic diversity of feeding habits on the tribal or generic level. As the core feeding apparatus, mouthparts have been relatively underexplored morphologically among genera or tribes within Melolonthinae. In this study, we conducted a detailed dissection and scanning electron microscopic (SEM) analysis of the adult mouthparts from six species across four tribes within Melolonthinae, to provide new morphological characters. The mouthparts exhibit considerable morphological diversity, including variations in labral notches, invaginations on epipharynx, mandibular structures, and the arrangement of setae on the labia. Using SEM, we observed paired invaginations on the epipharynx in Brahmina faldermanni , Hilyotrogus bicoloreus , Polyphylla laticollis and Melolontha incana , which are absent in the Miridiba trichophora , and Apogonia niponica. The structural diversity may be linked to the different feeding habits of these beetles, a relationship that is briefly discussed in the study. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hydrobiology / Shuisheng Shengwu Xuebao is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The periodic outbreaks of Acanthaster spp. which are predators of coral, are important reasons for the degradation of coral reefs. Information on the food sources of Acanthaster spp. Would be useful for suppressing outbreaks of the species. Although field observations on the feeding habits of Acanthaster spp., suggest that they feed mainly on corals, no isotopic evidence has been provided to support this. Therefore, this study was conducted to explore the food sources of Acanthaster spp. from the perspective of stable carbon (δ13C) and nitrogen isotopes (δ15N) by analyzing the consistency of the δ13C values of food in the gastric contents and pyloric gut as well as the significance of their δ13C and δ15N values, with the goal being to attain new information for comprehensively understanding or controlling outbreaks of these predators. In March 2020, various Acanthaster spp. were collected from the reef slope of coral reefs in the Xisha Islands, at a water depth of less than 10 m. The sampled individuals were immediately placed in a -20°C refrigerator for transport to the laboratory, after which they were stored in -80°C freezer. The gastric contents and pyloric gut were extracted for measurement of δ13C and δ15N values to investigate the feeding habits of Acanthaster spp. for the first time. The collected individuals were divided into three age groups: sub-adult (10~200 mm diameter), adult (200~350 mm), and senile-adult (> 350 mm). The δ13C values of the gastric contents and pyloric gut were -15.03‰~-13.00‰ and -15.21‰~-13.24‰, respectively. The average change in δ13C values (△ δ13C) between the gastric contents and pyloric gut were 0.17‰, 0.20‰, and 0.04‰ for the sub-adult, adult, and senile-adult groups, respectively. The results showed the following: (1) The δ13C values of the gastric contents correlated positively with those of the pyloric gut for Acanthaster spp. of different diameters. There were no significant differences in average δ13C values between the gastric contents and pyloric gut. The same correlation trend between the gastric contents and pyloric gut, indicated a similar presentation of feeding habits. Both the gastric contents and pyloric gut can be used for food research; and (2) With increase in the Acanthaster spp. diameter and age, the δ13C values of the gastric contents and pyloric gut showed a decreasing trend. By contrast, the δ15N values of the gastric contents showed an increasing trend, indicating the variable properties of the food ingested. Specifically, the trophic level of the food tended to increase. The food trophic level was relatively low for sub-adults or individuals of a shorter diameter whereas it was relatively high for the larger and older individuals. These study findings provide new reference data for exploring the feeding habits of Acanthaster spp. at different growth phases and understanding the reasons for their outbreaks. [ABSTRACT FROM AUTHOR]

The European badger is a highly adaptable species, inhabiting a range of environments across Europe, from woodlands to urban areas, with its behaviour influenced by environmental conditions and human activities. This study examines the badger feeding habits, patterns of diel activity, and sett site choice in north-western Italy, assessing how landscape composition affects these behaviours. We conducted our research across seven study areas in northern Italy from December 2020 to November 2022, utilising camera trapping, faeces analysis, and sett surveys. Our findings revealed significant dietary variation, with earthworms being the primary food source in natural landscapes, while fleshy fruits being consumed especially in mixed and heavily modified landscapes, up to constitute the staple of the diet in one agricultural area. Badgers were found to be nocturnal, primarily active between sunset and sunrise. Setts varied considerably in structure and location, with a preference for natural grounds over human-made structures; key factors influencing sett site choice included slope, exposure, and vegetation cover. This study underscores the European badger's remarkable adaptability, illustrating how its diet, activity patterns, and sett site preferences are shaped by a complex interplay of factors, allowing the species to thrive in both pristine and modified environments across northern Italy. [ABSTRACT FROM AUTHOR]

The present study aimed to assess the feeding habits of Sebastes oculatus from the analysis of stomach content and to evaluate the influence of environmental and biological variables on occurrence of prey in stomach. Results showed that S. oculatus feeds mainly on the squat lobster Grimothea gregaria, crustacean megalopa, polychaetes and fish. The main factor that influenced occurrence of prey in stomach was the season and the importance of these prey items varied from season to season. The diet composition of S. oculatus gives clear evidence of its carcinophagous habits. The species feeds mostly on demersal and benthic invertebrates, but also on some pelagic fishes and crustaceans that live on the rocky reef. It allows assuming that S. oculatus is an ambush predator that does not actively search for its prey. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The periodic outbreaks of Acanthaster spp. which are predators of coral, are important reasons for the degradation of coral reefs. Information on the food sources of Acanthaster spp. Would be useful for suppressing outbreaks of the species. Although field observations on the feeding habits of Acanthaster spp., suggest that they feed mainly on corals, no isotopic evidence has been provided to support this. Therefore, this study was conducted to explore the food sources of Acanthaster spp. from the perspective of stable carbon (δ13C) and nitrogen isotopes (δ15N) by analyzing the consistency of the δ13C values of food in the gastric contents and pyloric gut as well as the significance of their δ13C and δ15N values, with the goal being to attain new information for comprehensively understanding or controlling outbreaks of these predators. In March 2020, various Acanthaster spp. were collected from the reef slope of coral reefs in the Xisha Islands, at a water depth of less than 10 m. The sampled individuals were immediately placed in a -20°C refrigerator for transport to the laboratory, after which they were stored in -80°C freezer. The gastric contents and pyloric gut were extracted for measurement of δ13C and δ15N values to investigate the feeding habits of Acanthaster spp. for the first time. The collected individuals were divided into three age groups: sub-adult (10~200 mm diameter), adult (200~350 mm), and senile-adult (>350 mm). The δ13C values of the gastric contents and pyloric gut were -15.03‰~-13.00‰ and -15.21‰~-13.24‰, respectively. The average change in δ13C values (△δ13C) between the gastric contents and pyloric gut were 0.17‰, 0.20‰, and 0.04‰ for the sub-adult, adult, and senile-adult groups, respectively. The results showed the following: (1) The δ13C values of the gastric contents correlated positively with those of the pyloric gut for Acanthaster spp. of different diameters. There were no significant differences in average δ13C values between the gastric contents and pyloric gut. The same correlation trend between the gastric contents and pyloric gut, indicated a similar presentation of feeding habits. Both the gastric contents and pyloric gut can be used for food research; and (2) With increase in the Acanthaster spp. diameter and age, the δ13C values of the gastric contents and pyloric gut showed a decreasing trend. By contrast, the δ15N values of the gastric contents showed an increasing trend, indicating the variable properties of the food ingested. Specifically, the trophic level of the food tended to increase. The food trophic level was relatively low for sub-adults or individuals of a shorter diameter whereas it was relatively high for the larger and older individuals. These study findings provide new reference data for exploring the feeding habits of Acanthaster spp. at different growth phases and understanding the reasons for their outbreaks.

Pentatomidae includes many species of significant economic value as plant pests and biological control agents. The feeding habits of Pentatomidae are closely related to their energy metabolism and ecological adaptations. In this study, we sequenced the mitochondrial genomes of 12 Asopinae species using the next‐generation sequencing to explore the effect of dietary changes on mitochondrial genome evolution. Notably, all sequences were double‐stranded circular DNA molecules containing 37 genes and one control region. We then compared and analyzed the mitochondrial genome characteristics of phytophagous and predatory bugs. Notably, no significant difference was observed in the length of the mitochondrial genomes between the predatory and phytophagous bugs. However, the AT content was higher in the mitochondrial genomes of phytophagous bugs than that of predatory bugs. Moreover, phytophagous bugs prefer codon usage patterns ending in A/T compared with predatory bugs. The evolution rate of predatory bugs was lower than that of phytophagous bugs. The phylogenetic relationships across phytophagous bugs' lineages were largely consistent at depth nodes based on different datasets and tree‐reconstructing methods, and strongly supported the monophyly of predatory bugs. Additionally, the estimated divergence times indicated that Pentatomidae explosively radiated in the Early Cretaceous. Subsequently, the subfamily Asopinae and the genus Menida diverged in the Late Cretaceous. Our research results provide data supporting for the evolutionary patterns and classification of Pentatomidae. [ABSTRACT FROM AUTHOR]

This study explored the diet and food composition of the European Pond Turtle, Emys orbicularis, population in Anzali Lagoon, located in the South Caspian region. A total of 186 turtles were captured during both the pre- and post-breeding seasons to analyse their stomach contents. The analysis revealed that the diet primarily consisted of Arthropoda (76.2%), followed by Mollusca (12.2%), fish (4.6%), aquatic plant material (6.0%), and Annelida (0.9%). The average number of food items during the breeding season was 14 per sample, which significantly decreased to 2.5 in the post-breeding season. On average, male turtles consumed three food items, while females consumed six during the study period. The Pianka Index indicated a high degree of dietary overlap among males, females, and juveniles. Moreover, the Shannon Index revealed food item diversity values of 1.1 for males, 0.94 for females, and 0.62 for juveniles. These findings suggest that the European Pond Turtle in Anzali Lagoon is an opportunistic feeder, with its diet ranging from carnivorous to omnivorous, depending on environmental conditions, season changes, and food availability. [ABSTRACT FROM AUTHOR]

Lakes and their basins are major repositories of biodiversity. Monitoring the basin and their respective water bodies requires an assessment of avifaunal diversity, as birds are a health indicator of the ecosystem. The present investigation focused on the avifauna diversity of Moharli Lake and its environs. Moharli Lake is located a short distance from the Tadoba Andhari Tiger Reserve (TATR) in the Chandrapur district of Maharashtra. Serving as one of the primary entrances to TATR, the Moharli gate overlooks this perennial freshwater lake. Abundant in nutrients, the lake supports a diverse avian population, including migratory bird species. The lake and its environs were surveyed nightly throughout the study duration, spanning from June 2014 to April 2015. The birds were classified into five distinct groups based on their habitat. A total of 81 species, representing 67 genera across 31 families within 13 orders, were documented and classified according to their status and occurrence, including migratory species. The presence of birds was meticulously documented alongside their dietary inclinations and feeding behaviors. The diverse bird community within the study area indicates a conducive habitat for both breeding and sustenance. A comprehensive analysis of avifaunal diversity in this region will aid in formulating conservation strategies for the future. [ABSTRACT FROM AUTHOR]

In this study, we described and compared the diet, monthly feeding intensity, and condition of west coast steenbras (Lithognathus aureti) and silver kob (Argyrosomus inodorus) caught at a unique habitat in the northern Benguela. Stomach contents of 179 west coast steenbras and 114 silver kob caught from October 2020 to September 2022 were investigated. The peak in feeding intensity of west coast steenbras appeared to be opportunistic during winter and summer periods depending on food availability. The fish condition, however, peaked at the beginning (October) and at the end (April) of the austral summer spawning period, with the hepatosomatic index (HSI) at 1.5% and the condition factor (CF) at 0.022%. Seven prey taxa were found in the diet of west coast steenbras (bivalves, bony fishes, other mollusks, algae, crustaceans, cnidaria, and polychaetas) and six taxa in the diet of silver kob (bivalves, crustaceans, bony fishes, algae, starfish, and zooplankton), indicating generalist feeding behavior in both the species. The bivalves were the most important prey items in the diet of west coast steenbras (95.9% index of relative importance [IRI]). The most important prey items in the diet of silver kob were crustaceans (83.1% IRI) and bony fishes (16.0% IRI). Crustaceans were most important in the diet of small‐to‐medium‐sized silver kob, whereas bony fishes were most important in the diet of larger silver kob (>75 cm), with significant differences of IRI% by size class. Schoener's index of niche overlap indicated a relatively low overall niche overlap (0.11) between west coast steenbras and silver kob. This allows them to coexist as their feeding habits allow them to occupy unique niches in the coastal reef and sandy habitat and reduce competition for resources. [ABSTRACT FROM AUTHOR]

In order to understand the feeding habits of Ommastrephes bartramii and explore its position in the food web and ecological function, we analyzed the food composition of 15 Ommastrephes bartramii samples which were collected in the high sea of Northwest Pacific Ocean using high-throughput sequencing. The results showed that there were 646 980 high-quality sequences in 15 samples, a total of 624 operational taxonomic units (OTUs) were obtained through cluster analysis. A total of 65 food species, belonging to 6 phyla, 11 classes, 22 orders, 37 families and 51 genera, were detected by screening and comparison. Ommastrephes bartramii fed mainly on cephalopods, fishes, and a variety of Zooplanktons (including Euphausiid, Ostracod, Medusae, etc.). The dominant prey species included Sardinops sagax, Onychoteuthis borealijaponica, Gonatopsis borealis, Watasenia scintillans, Notoscopelus caudispinosus, etc. In conclusion, the feeding range of Ommastrephes bartramii was wide, and the food species were related to the natural preys in the sea area. Furthermore, Ommastrephes bartramii showed different feeding preferences among different mantle length groups. The analysis of the whole composition of stomach contents of Ommastrephes bartramii plays an important role in digging out the relationship between feeding and life history, such as growth, migration and reproduction. This provides a scientific basis for the sustainable development and conservation of Ommastrephes bartramii resources from the perspective of ecosystem. [ABSTRACT FROM AUTHOR]

Engin, S.; Gurkan, S., and Taskavak, E., 2024. Cellular changes in liver tissue of adult common sole (Solea solea L. 1758) in the Aegean Sea, Turkey. Journal of Coastal Research, 40(4), 740–748. Charlotte (North Carolina), ISSN 0749-0208. In this study, cellular changes and biological indices in the liver tissue of the common sole, Solea solea (L. 1758), are investigated based on sex, size groups, and seasons. The specimens used in the study were obtained monthly between 2019 and 2020 from commercial trawlers and small scale–fishing operations in the fishing grounds of Izmir Bay, the Aegean Sea coast of Turkey. A total of 240 common sole fish (166 female, 66 male, 8 immature) were used in this study. In the obtained specimens, the male: female ratio was determined as 0.39:1 (χ2 = 33.19; p > 0.05), whereas the length–weight relationship was calculated as W = 0.009TL2.97 (R2 = 0.86) for females and W = 0.009TL3.27 (R2 = 0.91) for males. Four size groups (19–22, 23–26, 27–30, >30cm) were established in the study. Significant histological changes, such as macrovesicular steatosis degenerations, were observed in the liver tissue of the examined fish, especially in larger size groups. Females exhibited higher levels of condition and hepatosomatic index values compared with males, possibly because they are more susceptible to liver degeneration. During the summer months, liver degeneration is more striking due to hunger among common soles. Based on these results, 36.7% of the specimens caught from fishing grounds in Izmir Bay have normal liver tissues, whereas 11.3% have macrosteosis and 8.3% have a sinusoidal hemorrhage. [ABSTRACT FROM AUTHOR]

The alien Red Sea goatfish, Parupeneus forsskali (Fourmanoir & Guézé, 1976), is a Lessepsian migrant, entering the Mediterranean through the Suez Canal. This study explores its seasonal diet and biological traits in Cyprus, its non-native habitat. From August 2019 to July 2021, a total of 249 specimens were collected, ranging in total length (TL) from 5.8 to 27.7 cm, with a mean TL of 15.1 ± 4.54 cm (SD). These specimens were examined with respect to sex and season. Through various methods (F%, N%, W%, and IRI), the feeding habits of the species were analysed, revealing a diet dominated by Crustacea (mainly Decapoda) and Polychaeta, with the secondary consumption of Mollusca, Echinodermata, and others. Significant differences were found between males and juveniles and females and juveniles, with adults preferring Decapoda and juveniles Copepoda, while seasonal variations were mainly influenced by prey availability. The Red Sea goatfish exhibited ontogenetic niche shifts in its depth and habitat distribution, influenced by size and age. The trophic level (TROPH) of P. forsskali ranged from 3.22 to 3.46, corresponding to an omnivorous diet with a preference for animals. These findings suggest that P. forsskali is an opportunistic predator with a diverse diet, thriving in its new habitat and potentially impacting the local marine food webs by competing with economically important native species for resources. [ABSTRACT FROM AUTHOR]

The food and feeding habits of Schizothorax niger in Dal-lake was studied by examining guts collected throughout the year.The fish samples used in the study was within the range of 200mm to 340mm in total length and weight ranging from 100g to 424g in weight and the sampling duration was from March 2021 to April 2022.During the analysis the food and feeding habits of S.niger it was concluded that the fish is herbivorous.Its food mainly consists of plant matter 67.53% and 23.43% animal matter. Green algae, which made up around 30.01% of all food items, was the main contributor to the plant food. It was found to be at its highest (32.64%) in July and at its lowest (10.18%) in January. The primary source of animal food was crustaceans, which accounted for 16.20% of all food items. The highest percentage of crustaceans was reported in the month of February (30%), while the lowest percentage was recorded in the month of July (9%). [ABSTRACT FROM AUTHOR]

This letter reports a novel observation of terrestrial foraging behavior by the Indian Pond Heron (Ardeola grayii), highlighting its adaptability and resourcefulness in exploiting diverse food sources. The study documents the heron's unusual feeding habits in Kollam Beach, India, where it demonstrates a preference for terrestrial environments despite its aquatic habitat. Through detailed observations and video recordings, the authors shed light on the heron's foraging behavior and its implications for our understanding of wading bird ecology. [ABSTRACT FROM AUTHOR]

The purpose of this study was to analyze the influence of socio-demographic characteristics on feeding habits of inhabitants of Katagum local government Area of Bauchi state, Nigeria. The two nominal independent variables used in the descriptive survey are income level, and culture/ethnicity. This study employed the descriptive survey design. The population of the study was drawn from three districts council of Katagum local Government Area in Bauchi State Nigeria. Three hundred and ninety nine (399) respondents was conveniently selected using stratified random sampling and convenient sampling techniques, the instrument used for collecting data for this study was questionnaire named Socio-demographic characteristics data (SDCDQ) and food frequency list (FFL), data collected was statistically analyzed using descriptive and inferential statistics. The result revealed that income level was not significantly influenced by the feeding habit of the Katagum inhabitants, which implies that there is no significant difference between feeding habit and income level. The findings further discovered that culture/ethnicity shows there is no significant difference between feeding habit and culture/ethnicity; the study concludes that the inhabitant feeding habit was not influenced by their various cultures. Based on these findings it was recommended among others that the government should ensure food self-sufficiency and provide necessary infrastructure to stimulate economic activities, enhance incomes and improve living conditions of the poor.

Population systems in which all three taxa of the Pelophylax esculentus complex coexist are rare and in Serbia can only be found along the Danube. Although several studies describe the diet in populations with only one taxon, there is a lack of data from mixed populations. We studied the diet in mixed populations of edible frogs at three sites for three years. We collected gut contents from 221 adult frogs using the stomach flushing method and identified 1,477 prey items. The diet consisted mainly of insects (88%). For all three taxa, the most frequently consumed prey groups were Hymenoptera (28%), Coleoptera (18%), Lepidoptera (17%) and Diptera (11%). Larger prey (in terms of length and volume) was mainly consumed by P. ridibundus, followed by P. esculentus. The smallest prey were mainly consumed by P. lessonae. However, P. ridibundus consumed fewer prey items than P. lessonae. No significant difference was found between the taxa in the staple diet, while there were differences in the less abundant prey categories, especially between P. ridibundus and P. lessonae. The narrowest trophic niche width was observed in P. lessonae, followed by P. esculentus, and the widest in P. ridibundus. Our results suggest that the diet of the three taxa is diverse and consists of a large number of invertebrate groups. However, the diet was locality-specific, with the dominance of different prey groups in different localities depending on habitat characteristics. These results confirm our expectation that the frogs of the Pelophylax esculentus complex follow an opportunistic foraging strategy, as predicted by optimal foraging theory. [ABSTRACT FROM AUTHOR]

The Pacific Porgy (Calamus brachysomus) is a commercially important fish in Baja California Sur, Mexico, where it reproduces year-round. The feeding habits of fishes can change during reproductive stages in response to changes in energetic demand. The objective of this study was to characterize the trophic habits of the Pacific Porgy and how these varied by sex, reproductive stage, and season. Monthly samples were obtained from July 2015 to July 2016 in the central Gulf of California. The stomach contents of 235 specimens (108 males and 127 females) were analyzed. The trophic spectrum comprised 90 prey items, including 58 mollusks, 14 echinoderms, 13 arthropods, 2 chordates, 1 annelid, 1 poriferan, and algal remains. According to the prey-specific index of relative importance (%PSIRI), the most important prey items were the bivalves Transennella spp. (7.24%), Argopecten spp. (6.94%), Anadara spp. (6.25%), Septifer zeteki (6.19%), and Tivela spp. (6.1%). The trophic spectrum varied significantly by season but not by sex or reproductive stage. There were no significant interactions between sex and season or sex and reproductive stage. According to the Levin index, C. brachysomus exhibited a narrow trophic niche (Bi = 0.31). Costello graphs indicated the dominance of a few species, with shifts in the relative abundance of prey species. Based on the trophic analysis, C. brachysomus was classified as a tertiary consumer (3.18). Therefore, C. brachysomus represents an important link between upper and lower trophic levels. Based on these results, we inferred that the Pacific Porgy is an opportunistic predator that feeds actively during all reproductive stages. Thus, the energetic requirements needed for reproduction appear to be covered by the prey that comprise the trophic spectrum of C. brachysomus without this species needing to switch to more energy-rich prey. [ABSTRACT FROM AUTHOR]

Information on the feeding habits of the critically endangered Irrawaddy dolphin (Orcaella brevirostris) in the Mekong River and how their diet overlaps with that of the species targeted by fisheries is limited. The information provided herein will be helpful for evaluating and protecting important dolphin food resources. The composition of large prey species of Irrawaddy dolphins and the extent of fish resources were surveyed in the Mekong River, Cambodia, using local ecological knowledge. The results showed that Irrawaddy dolphins fed on 13 species of large fish, with Pangasius conchophilus, Cyclocheilichthys enoplos, and Hemibagrus wyckii the most frequently consumed prey. Twelve of the 13 reported prey species were usually caught by fishers. The results also revealed that the average weight of fish caught daily by fishers was significantly lower in 2019 than about five years before that, regardless of the season. A significant decline in fish resources and a high overlap of dolphin diets with fishery target species indicate that Irrawaddy dolphins may also be threatened by prey depletion, especially during the dry season when dolphins are concentrated in deep pools. [ABSTRACT FROM AUTHOR]

Introduction: Heavy metals are ubiquitous environmental pollutants, and fish could be contaminated by these metals, potentially posing a threat to human health through the food chain. Understanding the accumulation of these metals in fish tissues is crucial for assessing the safety of consuming fish products. Methods: In this study, the distribution of nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) in tissues of eight fish species (Ctenopharyngodon idellus, Megalobrama amblycephala, Hypophthalmichthys molitrix, Hypophthalmichthys nobilis, Carassius auratus, Cyprinus carpio, Culter alburnus, and Lateolabrax japonicas) collected from the Baishazhou market with different trophic levels and habitat preference was investigated using inductively coupled plasma mass spectrometry (ICP-MS). The metal accumulation capacity of different fish tissues and species was assessed, and the metal pollution index (MPI) was calculated to evaluate the extent of metal accumulation ability in each species. Additionally, the health risk assessment was conducted to evaluate the potential threat to human health posed by consuming these fish species. Results: The levels of metals exhibited variation among different fish tissues and species, showing an order of Zn > Cu > Ni > Pb > Cd. In terms of tissues, fish head demonstrated a greater capacity for metal accumulation compared to the muscles. Regarding fish species, the extent of accumulation ability varied depending on the specific metal, exhibiting the following order according to MPI: H. molitrix (0.568) > C. auratus (0.508) > M. amblycephala (0.469) > C. idellus (0.336)>C. alburnus (0.315)>C. carpio (0.274)>L. japonicus (0.263)>H. nobilis (0.206). Furthermore, in accordance with the results of health risk assessment, there was no potential health risk associated with the consumption of these fish species, as all target hazard quotient (THQ) values (ranger from not detected to 0.192) were below 1, and the maximum hazard index (HI) value was observed in C. carpio (0.519 for adults, 0.622 for children). Conclusion: The findings of this study demonstrate the distribution of heavy metals in fish tissues and indicate there were no potential health risk associated with consuming these fish bought from the Baishazhou market. [ABSTRACT FROM AUTHOR]

Microbial communities, derived from food, ambient, and inner, can affect host ecological adaption and evolution. Comparing with most phytophagous arthropods, predators may have more opportunities to develop specific microbiota depending on the level of prey specialization. To explore how diet sources affect host microbial communities and vary across predator species, we considered 3 types of predators from Phytoseiidae (Acari: Mesostigmata): polyphagous (Amblyseius orientalis Ehara, Neoseiulus barkeri Hughes, and Amblyseius swirskii Athias‐Henrio), oligophagous (Neoseiulus californicus McGregor), and monophagous (Phytoseiulus persimilis Athias‐Henriot) predatory mites. The polyphagous species were fed on 2 types of diets, natural prey and alternative prey. By using 16S rRNA sequencing, we found that diet was the main source of microbiota in predatory mites, while there was no clear pattern affected by prey specialization. Among 3 polyphagous predators, host species had a larger impact than prey on microbial composition. Unlike A. orientalis or N. barkeri which showed consistency in their microbiota, prey switching significantly affected β‐diversity of bacterial composition in A. swirskii, with 56% of the microbial alteration. In short, our results confirmed the substantial influence of diet on host microbial construction in predatory species, and highlighted species differences in shaping the microbiota which are not necessarily related to prey specialization. [ABSTRACT FROM AUTHOR]

Large-bodied animals, such as the Mekong giant catfish (Pangasianodon gigas), may modify prey communities and affect their potential competitors for food resources by consuming large quantities of prey. The Mekong giant catfish is a key representative of freshwater megafauna and is stocked in reservoirs in Thailand for species conservation and fishery stock enhancement. However, their biological interactions with other sympatric animals remain unclear. Here, we aimed to investigate the trophic niche of the Mekong giant catfish in a Thai reservoir by comparing stable carbon and nitrogen isotope ratios (δ13C and δ15N, respectively) and fatty acid (FA) composition with those of five other sympatric fish species. The δ13C value of the Mekong giant catfish was –24.4 ± 1.0‰ (mean ± SD), the second highest among the sympatric fish species, suggesting relatively weak reliance on phytoplankton-based food chains. The δ15N value of the Mekong giant catfish was 10.7 ± 0.4‰, intermediate between those of herbivorous and carnivorous fishes, indicating that it is not a primary consumer. The FA composition of the Mekong giant catfish significantly differed from those of the other fish species and was characterized by a large proportion of long-chain FA, including 22:6n-3, 20:5n-3, and 20:1n-9. The δ13C, δ15N, and FA signatures suggest that the Mekong giant catfish occupy distinct trophic niches in food webs. Our results highlight that it is necessary to monitor the ecological impacts of released Mekong giant catfish on lower-level consumers through their foraging in receiving reservoirs. [ABSTRACT FROM AUTHOR]

Abstract Pentatomidae includes many species of significant economic value as plant pests and biological control agents. The feeding habits of Pentatomidae are closely related to their energy metabolism and ecological adaptations. In this study, we sequenced the mitochondrial genomes of 12 Asopinae species using the next‐generation sequencing to explore the effect of dietary changes on mitochondrial genome evolution. Notably, all sequences were double‐stranded circular DNA molecules containing 37 genes and one control region. We then compared and analyzed the mitochondrial genome characteristics of phytophagous and predatory bugs. Notably, no significant difference was observed in the length of the mitochondrial genomes between the predatory and phytophagous bugs. However, the AT content was higher in the mitochondrial genomes of phytophagous bugs than that of predatory bugs. Moreover, phytophagous bugs prefer codon usage patterns ending in A/T compared with predatory bugs. The evolution rate of predatory bugs was lower than that of phytophagous bugs. The phylogenetic relationships across phytophagous bugs' lineages were largely consistent at depth nodes based on different datasets and tree‐reconstructing methods, and strongly supported the monophyly of predatory bugs. Additionally, the estimated divergence times indicated that Pentatomidae explosively radiated in the Early Cretaceous. Subsequently, the subfamily Asopinae and the genus Menida diverged in the Late Cretaceous. Our research results provide data supporting for the evolutionary patterns and classification of Pentatomidae.

The European badger is a highly adaptable species, inhabiting a range of environments across Europe, from woodlands to urban areas, with its behaviour influenced by environmental conditions and human activities. This study examines the badger feeding habits, patterns of diel activity, and sett site choice in north-western Italy, assessing how landscape composition affects these behaviours. We conducted our research across seven study areas in northern Italy from December 2020 to November 2022, utilising camera trapping, faeces analysis, and sett surveys. Our findings revealed significant dietary variation, with earthworms being the primary food source in natural landscapes, while fleshy fruits being consumed especially in mixed and heavily modified landscapes, up to constitute the staple of the diet in one agricultural area. Badgers were found to be nocturnal, primarily active between sunset and sunrise. Setts varied considerably in structure and location, with a preference for natural grounds over human-made structures; key factors influencing sett site choice included slope, exposure, and vegetation cover. This study underscores the European badger’s remarkable adaptability, illustrating how its diet, activity patterns, and sett site preferences are shaped by a complex interplay of factors, allowing the species to thrive in both pristine and modified environments across northern Italy.

We conducted a field survey and rearing experiment to investigate habitat, larval morphology, and ecology of Diplectrona aiensis Kobayashi, 1987. Larvae of this species look similar to those of D. takaii Nozaki, 2021, originally described as Diplectrona sp. DC by Akagi (1956); however, they can be distinguished by shape of the secondary setae on the head, thoracic nota, and abdominal segments. Our results revealed that generations of D. aiensis have overwintering and non-overwintering cohorts. Larvae build their retreat and capture nets on boulders and among leaf patches and prefer lower water velocity (mean: 22.2 cm/s, range: 1.3 ≦ 52.4 cm/s). Until the third instar, they feed only on detritus and after that, they feed on both animal and plant matter. This is the first study to report morphology, habitat, and ecology of D. aiensis. [ABSTRACT FROM AUTHOR]

Large predators are essential in maintaining ecosystem functioning, and comprehending how their feeding habits change across natural and human-dominated landscapes is crucial to preserve biodiversity. In this study, the diet of Iberian wolves (Canis lupus signatus) during pup rearing season (July to September) has been studied in relation to prey abundance and putting emphasis in the analysis of the differences between zones, wolf groups and individual factors (age, sex and social status). For this, non-invasive monitoring was carried out in three zones of Spain where nine different wolf breeding groups were detected (Galicia, n = 4; Zamora, n = 4 and Valladolid, n = 1). Faecal samples were collected near breeding sites for dietary and genetic analyses, registering if it was or not a scent mark to know the social status of the individuals. Prey availability was determined by camera trapping or requesting the official census of wild prey in the study areas. We found differences in wolf’s diet depending on the zone and the breeding group however, the diet did not vary depending on the age, sex and social status. In general, Iberian wolves mainly fed on wild ungulates (wild boar, roe deer and red deer), feeding on the most abundant prey, except for Baldriz group in Galicia which seems to be specialized in hunting roe deer. Domestic animals’ consumption (sheep, goat, donkey, pig) was not high, but it occurred specially in agriculture and livestock areas (Ferreras in Zamora and Valladolid) where wild prey were less available. Significance statement: In this study, we shed light on the vital role of Iberian wolves in the ecosystem by investigating the dietary preferences during pup rearing season across different landscapes. Our research revealed differences in wolf diets based on geographic location and breeding groups, emphasizing their adaptability. We found that age, sex, and social status did not significantly influence their dietary preferences. Iberian wolves predominantly target wild ungulates, except for a specialized group in Galicia. Our study introduces a novel approach as it is the first to analyse wolf diet based on individual factors and using nitrogen analysis. Additionally, the study highlights previously overlooked dietary patterns of the Iberian wolf subspecies, despite its critical role in the ecosystem as a top predator. Furthermore, we emphasize the necessity of conserving wild ungulate populations to reduce livestock attacks by ensuring a stable supply of wild prey, promoting coexistence between humans and wolves. [ABSTRACT FROM AUTHOR]

The forest green tree frog, Zhangixalus arboreus, is a Rhacophorid species naturally distributed in Honshu and Sado Islands from Japan. This species is also known to have been introduced to the Izu-Oshima Island. In this study, we examined the feeding habits of Z. arboreus in Izu-Oshima Island because the knowledge of its foraging strategies may contribute to addressing conservation efforts on the island. We observed that frog stomachs contained 65 animal prey items, exclusively arthropods belonging to classes Arachnida, Insecta, and Diplopoda. The frog stomachs contained terrestrial and arboreal arthropods, suggesting that Z. arboreus feeds in a variety of habitats. We also found a large number of ants in frog stomachs. Our results differ from a previous study carried out on native populations of this species, which may be indicative of habitat differences among populations. [ABSTRACT FROM AUTHOR]

Feeding habits and trophic level of juvenile greater amberjack, Seriola dumerili were studied using 170 specimens collected by set net fishery and lure fishing in the southern waters of Korea during July, August, September, October, and November 2022. The size of juvenile greater amberjack ranged from 17.5 to 49.9 cm in fork length. Juvenile greater amberjack was piscivorous predator that feed primarily on fish. We calculated the trophic level as 4.06 ± 0.80 for juvenile greater amberjack. Fishes were the main prey items for all size groups. Juvenile greater amberjack also showed size-related dietary shift from Japanese anchovy to jack mackerel. As the fork length of juvenile greater amberjack increase, the mean weight of prey per stomach tended to increased, while the mean number of preys per stomach was not significantly different. Fishes were the main prey items for summer and autumn. The main fish prey during summer and autumn was Japanese anchovy, but in the autumn, the Japanese anchovy portion decreased, and the jack mackerel portion increased. PERMANOVA analysis was used to examine seasonal and size-related changes in diet composition, which showed significant variations among size classes. Juvenile greater amberjack presumably feed on larger prey to meet their energy requirements. [ABSTRACT FROM AUTHOR]

Population systems in which all three taxa of the Pelophylax esculentus complex coexist are rare and in Serbia can only be found along the Danube. Although several studies describe the diet in populations with only one taxon, there is a lack of data from mixed populations. We studied the diet in mixed populations of edible frogs at three sites for three years. We collected gut contents from 221 adult frogs using the stomach flushing method and identified 1,477 prey items. The diet consisted mainly of insects (88%). For all three taxa, the most frequently consumed prey groups were Hymenoptera (28%), Coleoptera (18%), Lepidoptera (17%) and Diptera (11%). Larger prey (in terms of length and volume) was mainly consumed by P. ridibundus, followed by P. esculentus. The smallest prey were mainly consumed by P. lessonae. However, P. ridibundus consumed fewer prey items than P. lessonae. No significant difference was found between the taxa in the staple diet, while there were differences in the less abundant prey categories, especially between P. ridibundus and P. lessonae. The narrowest trophic niche width was observed in P. lessonae, followed by P. esculentus, and the widest in P. ridibundus. Our results suggest that the diet of the three taxa is diverse and consists of a large number of invertebrate groups. However, the diet was locality-specific, with the dominance of different prey groups in different localities depending on habitat characteristics. These results confirm our expectation that the frogs of the Pelophylax esculentus complex follow an opportunistic foraging strategy, as predicted by optimal foraging theory.

The Pacific Porgy (Calamus brachysomus) is a commercially important fish in Baja California Sur, Mexico, where it reproduces year-round. The feeding habits of fishes can change during reproductive stages in response to changes in energetic demand. The objective of this study was to characterize the trophic habits of the Pacific Porgy and how these varied by sex, reproductive stage, and season. Monthly samples were obtained from July 2015 to July 2016 in the central Gulf of California. The stomach contents of 235 specimens (108 males and 127 females) were analyzed. The trophic spectrum comprised 90 prey items, including 58 mollusks, 14 echinoderms, 13 arthropods, 2 chordates, 1 annelid, 1 poriferan, and algal remains. According to the prey-specific index of relative importance (%PSIRI), the most important prey items were the bivalves Transennella spp. (7.24%), Argopecten spp. (6.94%), Anadara spp. (6.25%), Septifer zeteki (6.19%), and Tivela spp. (6.1%). The trophic spectrum varied significantly by season but not by sex or reproductive stage. There were no significant interactions between sex and season or sex and reproductive stage. According to the Levin index, C. brachysomus exhibited a narrow trophic niche (Bi = 0.31). Costello graphs indicated the dominance of a few species, with shifts in the relative abundance of prey species. Based on the trophic analysis, C. brachysomus was classified as a tertiary consumer (3.18). Therefore, C. brachysomus represents an important link between upper and lower trophic levels. Based on these results, we inferred that the Pacific Porgy is an opportunistic predator that feeds actively during all reproductive stages. Thus, the energetic requirements needed for reproduction appear to be covered by the prey that comprise the trophic spectrum of C. brachysomus without this species needing to switch to more energy-rich prey.

Lakes and their basins are major repositories of biodiversity. Monitoring the basin and their respective water bodies requires an assessment of avifaunal diversity, as birds are a health indicator of the ecosystem. The present investigation focused on the avifauna diversity of Moharli Lake and its environs. Moharli Lake is located a short distance from the Tadoba Andhari Tiger Reserve (TATR) in the Chandrapur district of Maharashtra. Serving as one of the primary entrances to TATR, the Moharli gate overlooks this perennial freshwater lake. Abundant in nutrients, the lake supports a diverse avian population, including migratory bird species. The lake and its environs were surveyed nightly throughout the study duration, spanning from June 2014 to April 2015. The birds were classified into five distinct groups based on their habitat. A total of 81 species, representing 67 genera across 31 families within 13 orders, were documented and classified according to their status and occurrence, including migratory species. The presence of birds was meticulously documented alongside their dietary inclinations and feeding behaviors. The diverse bird community within the study area indicates a conducive habitat for both breeding and sustenance. A comprehensive analysis of avifaunal diversity in this region will aid in formulating conservation strategies for the future.

The alien Red Sea goatfish, Parupeneus forsskali (Fourmanoir & Guézé, 1976), is a Lessepsian migrant, entering the Mediterranean through the Suez Canal. This study explores its seasonal diet and biological traits in Cyprus, its non-native habitat. From August 2019 to July 2021, a total of 249 specimens were collected, ranging in total length (TL) from 5.8 to 27.7 cm, with a mean TL of 15.1 ± 4.54 cm (SD). These specimens were examined with respect to sex and season. Through various methods (F%, N%, W%, and IRI), the feeding habits of the species were analysed, revealing a diet dominated by Crustacea (mainly Decapoda) and Polychaeta, with the secondary consumption of Mollusca, Echinodermata, and others. Significant differences were found between males and juveniles and females and juveniles, with adults preferring Decapoda and juveniles Copepoda, while seasonal variations were mainly influenced by prey availability. The Red Sea goatfish exhibited ontogenetic niche shifts in its depth and habitat distribution, influenced by size and age. The trophic level (TROPH) of P. forsskali ranged from 3.22 to 3.46, corresponding to an omnivorous diet with a preference for animals. These findings suggest that P. forsskali is an opportunistic predator with a diverse diet, thriving in its new habitat and potentially impacting the local marine food webs by competing with economically important native species for resources.

Ornithosuchids are a Late Triassic pseudosuchian archosaur group, consisting of four species (three from South America, and one from Scotland). All of them have triangular skulls with a protruding premaxilla, large nostrils, an extensive diastema in their narrow snout, a short jaw that does not reach the anterior end of the skull, and serrated posteriorly curved teeth. For this clade, carnivorous and scavenger habits have been previously proposed. Within the Ornithosuchidae, Riojasuchus tenuisceps (from Argentina) has the most morphologically extreme characteristics. Based on CT scans of the preserved skulls we generated a 3D model, and over this, we estimated the volumes of the adductors and abductor muscles and the force exerted by each. From these data we built the finite element model and measured the bite force (1.8–2.3 kN). Lateral, tractive, and torsional forces were applied to the end of the snout to evaluate the structural response of the skull during feeding. The results show that R. tenuisceps could resist tractive and torsional stresses better than lateral stress. Additionally, we analysed the peculiar morphological characteristics of the skull and their functional implications. We observed that the upper and lower dental rows were laterally separated from each other, preventing the generation of a cutting line during occlusion, and therefore, R. tenuisceps would have fed on small-sized prey that it could swallow whole. The curved premaxilla and the short mandible would not allow it to bite with the tip of the snout (ruling out the scavenging hypothesis), but were instead more adequate to capturing prey suspended in a fluid. This set of results allows us to propose that R. tenuisceps could have had a zoophagous diet and a wading habit, being able to feed on fish, amphibians, or any small animals that they could catch from the shoreline.

The Wanshan Archipelago, situated in the Pearl River Estuary, stood as a key fishing ground in China, boasting abundant fishery resources. To investigate variations in trophic niches and food sources among different islands within the Wanshan Archipelago, and to advance research on fish food webs and energy flow in the Pearl River Estuary, this study conducted a survey of fish communities in nearshore islands (Guishan Island, Dongao Island) and offshore islands (Wailingding Island, Wanshan Island) using triple gill nets during the autumn of 2021. The trophic niche characteristics of fishery organisms in these islands were analyzed utilizing carbon and nitrogen stable isotope technology. The results indicated that trophic niche width and biodiversity of fish communities in the nearshore islands surpassed those in the offshore islands, and the food chain length exhibited a trend of Guishan Island (4.04) > Dongao Island (3.98) > Wanshan Island (3.91) > Wailingding Island (3.86). The trophic niche indexes (CR, NR, CD, and SEAc) of fish communities in nearshore islands were higher compared to those on offshore islands, while MNND and SDNND suggested that fish communities in offshore islands were at a lower trophic level. Zooplankton emerged as the primary food source for fishery organisms in the Wanshan Archipelago. Feeding rates on zooplankton were 68.8 % and 70.4 % in Guishan Island and Dongao Island, and 53.7 % and 58.0 % in Wailingding Island and Wanshan Island, respectively. The proportion of benthic organisms fed near offshore islands was higher than nearshore islands. This study speculated that the fish in nearshore islands may shift from zooplankton food chain to benthic food chain. In addition, this study compared the trophic niche differences among the four islands in the Pearl River Estuary, clarified the diversity of feeding sources and trophic structure within fish communities, and revealed significant distinctions in fish food webs between the islands inside and outside the Pearl River Estuary. It will provide new information on the trophic interactions of fish in the Pearl River Estuary, and help to promote the ecological development and sustainable use of fishery resources.

Wild bird research, particularly investigations of the interplay between feeding habits, diet, and alimentary tract anatomy, offers a captivating avenue for scientific exploration. While numerous studies have delved into the upper digestive tracts of various avian species, there remains a dearth of data on the upper digestive tract anatomy of the African green bee-eater (AG bee-eater, Merops viridissimus cleopatra). This study aimed to bridge this knowledge gap by elucidating the gross, microscopic, and histochemical features of the esophagus and stomach in AG bee-eaters, shedding light on their food preferences, and feeding habits. Ten adult, apparently healthy AG bee-eaters were examined, revealing structural organizations of the esophagus, proventriculus, and gizzard that parallel those observed in other avian species. Key findings encompass a protective mucous layer in the esophagus and proventriculus, coupled with a moderately thick cuticle, guarding against harm from stinging insects like bees and wasps. The upper digestive tract houses numerous mucous-secreting glands, secreting both protective acidic mucin and enzymatic-neutral mucins. The proventriculus, featuring a thin wall and abundant glandular activity, equips AG bee-eaters with vital gastric enzymes for digesting their high-protein diet. This adaptation aligns with the bird's compact upper digestive tract, well suited for processing relatively small food particles. Additionally, the ventriculus's muscular layer, moderately thick, aligns with the moderately coarser texture of the bee-eater's dietary preferences. Overall, this study unveils crucial anatomical adaptations enabling AG bee-eaters to thrive on a diet dominated by stinging insects. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution in freshwater environments has drawn considerable attention over the decades due to the risk posed by MPs to the aquatic fauna and human health. In this study, the occurrence of MPs was assessed from the gastrointestinal tracts (GIT) of indigenous fishes from Bhogdoi River, a tributary of River Brahmaputra, northeast hill region, Assam, India. All the fish species (n = 180) analysed showed 100% occurrence of MPs sampled from three stations of River Bhogdoi. A total of 488 microplastic particles were recorded from GIT of fishes collected. The mean abundance of MPs was highest in Station-II (7.64 ± 2.77 numbers individual−1) with lowest in S-I (3.17 ± 0.99 numbers individual−1). The MP size of 100–500 μm, MP shape of fibre (43.33%) and fragments (35.33%), blue colour MPs (26–37%) and polymer type PA (23–30%) were most prevalent in fishes analysed from River Bhogdoi. The mean abundance of MPs was higher in herbivore fishes (8.52 ± 1.22 numbers individual−1) as compared to carnivorous and omnivorous fish species with highest abundance in Labeo rohita (12.11 ± 2.13 numbers individual−1). Fibre and fragments with size range of 100–500 μm were dominant among all the feeding habits. Blue and black colour MPs were abundant among herbivore and carnivore fishes. Fourier transform infrared spectroscopy results confirmed that polyamide and polypropylene were the most abundant MP polymer in the fishes analysed. The present study provides baseline information of MPs in River Bhogdoi, Assam, for its future monitoring and assessment of contaminants. [ABSTRACT FROM AUTHOR]

Larvae of Notodontidae are peculiar for the noticeably modified anal prolegs, and the morphological differences on mouthparts during larval development. However, the underlying relationships between these morphological characters and living strategies are not well elucidated. In this study, the larvae of Uropyia meticulodina were obtained through rearing and observed using scanning electron microscopy. The larval mouthparts show morphological differences between the first and the final instar, especially on the mandibles, labral notches, and spinnerets. The larvae are also atypical for the specialized anal stemapoda carrying eversible distal glands and prominent setae on dorsal surface. Based on our observation, the larvae prefer to live and chew on the ventral surface of host leaves before their first molts, but are more frequently discovered to crawl or bite on the leaf edges during later instars. The morphology, biology, feeding, and defensive strategies were briefly discussed. [ABSTRACT FROM AUTHOR]

While the general diet of Mediterranean elasmobranchs has been widely studied, little is known about food partitioning and competition among sympatric species, despite these being important forces structuring marine communities. Using stomach content and stable isotope analyses, we investigated diet and trophic levels and evaluated the diet overlap and partitioning of Scyliorhinus canicula, Mustelus mustelus, and M. punctulatus in the northwestern Adriatic Sea. These shark species were confirmed as opportunistic mesopredators, but significant differences in their diets emerged. The two bentho-demersal Mustelus species had a larger trophic overlap with S. canicula than between each other. Given the pronounced morphological similarity of these two Mustelus species, this is likely a strategy to limit competition. The strictly benthic S. canicula showed a more varied diet compared to the other species. Stable isotope analysis highlighted that despite the smaller size and overlapping diets, S. canicula occupied a slightly higher trophic level. A better characterization of the trophic role of these species in the food web of the basin can be obtained from these data. At an ecosystem level, this information is essential to evaluate the possible consequences of the decline or recovery of the population of these exploited species. [ABSTRACT FROM AUTHOR]

Carotenoids are diet-based micronutrients important in health and coloration signaling. Related species with similar diets can differ in the kinds and levels of circulating carotenoids, which suggests specific physiological mechanisms to efficiently utilize these micronutrients, regardless of their availability. We explored whether diet and parental provisioning of unusual sources of carotenoids (fresh vegetal matter and vertebrate feces) can explain the occurrence and concentrations of carotenoids in the cinereous vulture Aegypius monachus , griffon vulture Gyps fulvus , and Egyptian vulture Neophron percnopterus nestlings, even when these pigments appear to not be deposited in their integumentary system. A greater diversity of wild prey in diet could be behind the profile of higher concentrations of carotenoids in the Egyptian vulture, the species with carotenoid-dependent coloration during adulthood, while differences in diet composition between cinereous and griffon vultures do not translate to different carotenoid profiles. The carotenoid profile appears to not be related to the ingestion of unusual matter rich in these compounds, although the infrequent occurrence of lycopene and unidentified γ-carotene-like compounds suggest that these vultures may be exploiting vegetal matter that left no identifiable unconsumed remains in the nest of Egyptian vultures. The consumption of green plant material by griffon vultures does not result in especially high levels of carotenoids when compared to the carotenoids found in cinereous vultures, which do not consume green plant material. Ungulate feces were not provisioned to Egyptian vulture nestlings, despite the fact they contain carotenoids that adults need for appropriate coloration. Overall, this study indicates that diet differences alone appear insufficient to explain contrasting interspecific carotenoid profiles, especially since all types of food consumed are considered to be poor in carotenoids, except vegetable matter. We suggest that nestling Egyptian vultures are comparatively efficient in uptaking carotenoids present in low concentrations in food when these compounds are not deposited in their integument, which suggests allocation to other functions. [ABSTRACT FROM AUTHOR]

Homoplectra Ross, 1938 (Hydropsychidae) comprises 24 species. Knowledge of the immature stages of species in this genus is quite poor. This study aimed to describe for the first time morphology of Homoplectra gracilis Nozaki, 2019 larvae, found in small headwater streams flowing throughout 'Satoyama', a unique and important ecosystem in Japan, and clarify its biology. Morphological observations showed that the larva of this species is unique among known Japanese species in having a small median triangular process on the anterior margin of the head. Final instar larvae were found throughout the year, whereas the second instar larvae were observed during July and November. The species retreated using various kinds of substrates; on/between leaves, plants roots, and under stones. Analysis of digestive tracts showed predominantly detritus in their diet along with remains of invertebrates. The larvae appeared to withstand drought which occur in the streams. [ABSTRACT FROM AUTHOR]

Feeding efficiency of mammalian herbivores is associated with skull traits known to differ between feeding guilds. As climate is known to affect the architecture and functional traits of plants, skull morphology may change as plant traits change along climate gradients. We tested whether skull traits of more than 70% of the extant bovid and cervid species are related to aridity, and whether these relationships differ across feeding guilds (browser, grazer, mixed feeder). We used muzzle width to represent food ingestion and masseteric fossa length to represent oral processing. For the models without phylogeny, both muzzle width and masseteric fossa length increased towards wetter climates for grazers, but not for mixed feeders or browsers. These patterns suggest that grazer diets may change more dramatically across aridity gradients than the other two groups, possibly linked to changes in both the architecture and toughness of grasses. In models accounting for phylogeny, no changes in either trait across aridity gradient were found, which appeared to be due to subfamily differentiation along the aridity gradient. Our results suggest that deeper insights into the evolution of herbivore skulls may be achieved by using quantified diet data to directly test plant trait effects on skull morphology. [ABSTRACT FROM AUTHOR]

The present work aimed to analyze the distribution of the electrosensory pores of the Daggernose Shark Carcharhinus oxyrhynchus identifying the organ's importance in the natural history of the species. By examining photographs and digital microscope videos, we found that C. oxyrhynchus possesses the highest abundance of pores among Carcharhiniformes. This suggests a well‐developed electroreceptor system, which may have maximized its evolutionary success in high turbidity environments. Furthermore, as a morphologically derived species, C. oxyrhynchus comprises a more complex and specialized electrosensory system. Notably, the species exhibits ontogenetic variation in pore abundance, highlighting the importance of a high‐resolution system for adults. The higher density of pores in the ventral region indicates a preference for benthic prey, despite also feeding on pelagic items. Moreover, the species has a high‐resolution electrosensory system and a high density of pores in the snout, which emphasizes the importance of the elongated snout that expands the electroreception search area coverage. Evolutionary convergence was observed in the development of the electrosensory system, as C. oxyrhynchus shares characteristics of pore distribution and abundance with phylogenetically unrelated species. [ABSTRACT FROM AUTHOR]

This research studied the food composition and feeding rhythm of Saurogobio dabryi in the lower reaches of the Jialing River, aimed to explore the seasonal difference of its feeding habits. Gut contents of 268 S. dabryi in the downstream (Hechuan section) of the Jialing River were collected seasonally from September 2015 to August 2016. The feeding habits of S. dabryi were studied by microscopic examination, analysis of similarity, and the Amundsen graphical method. A total of 26 food categories were identified, among which algae and organic detritus were the dominant food source for S. dabryi. Animal prey contributed relatively low proportions to the food of S. dabryi. Seasonal variations of food composition of S. dabryi were significant (P<0.05). Hierarchical cluster analysis shows that the food composition in autumn was significantly different from other seasons at a similarity level of 60%. The results indicated that the feeding rhythm of the S. dairyi in the lower reaches of the Jialing River showed significant seasonal changes (P<0.05); The feeding intensity and food amount gradually increased from spring to winter, which may be related to the morphological structure, breeding period, special habitat, and seasonal changes of biological prey of S. dabryi. [ABSTRACT FROM AUTHOR]

Food and feeding habits of large cyprinid fishes (Labeobarbus intermedius, Labeobarbus nedgia, and Labeo forskalii) had been investigated in the upper Blue Nile River, Ethiopia. Four sampling sites were selected and specimens were sampled during the post-rainy (November 2016) and dry (March 2017) seasons by gillnets of 6 cm, 8 cm, 10 cm, 12 cm, and 14 cm mesh sizes. Totally 401 fishes were collected and about 30.4% (122) of the samples were documented with empty guts and 279 (69.6%) of them were with non-empty guts. The whole contents of all non-empty gut specimens were taken, labeled, and preserved using a 5% formaldehyde solution for further analysis. In the laboratory, gut contents were examined and identified using compound and stereo microscopes. The relative importance of different food items in the diet compositions was analyzed using a frequency of occurrence and volumetric analysis. During the post-rainy season, insects and phytoplankton were mostly ingested as food items. However, during the dry season, phytoplankton was the most important food item in the diet of all cyprinid fishes of the river. Based on current study results, L. intermedius and L. nedgia might be omnivores in their diet but Labeobarbus forskalii seemed to be detritivorous.