scholarly journals Feeding activity of the cayenne pompano Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) in estuaries on the western coast of the state of Maranhão, Brazil

2019 ◽  
Vol 79 (2) ◽  
pp. 311-320
Author(s):  
A. C. L. Castro ◽  
J. W. J. Azevedo ◽  
H. R. S. Ferreira ◽  
L. S. Soares ◽  
J. R. Pinheiro-Júnior ◽  
...  

Abstract The present paper addresses the feeding activity of Trachinotus cayennensis, collected in Lençóis Bay (1°18’S – 1°19’S; 44°51’W – 44°53’W) on the western coast of the state of Maranhão, Brazil. Sampling was conducted between June 2012 and June 2013 using driftnets with stretch mesh sizes from 95 to 100 mm. A total of 205 individuals (114 females and 91 males) were analyzed. Statistically significant differences in the sex ratio were found in June, September and December 2012. Food items were analyzed based on frequency of occurrence and volumetric method, with the subsequent calculation of the alimentary importance index. Three size groups were defined to determine possible ontogenetic changes in eating habits based on the size range of the individuals collected: I (˂ 29 cm), II (29.1 to 37.0) and III (≥ 37.1). Eleven food item categories were identified: mollusks, polychaetes, crustaceans, nematodes, insects, algae, bryozoans, ophiuroids, fishes, vegetal matter and sediments. The variety of items in the diet of T. cayennensis indicates considerable feeding plasticity and opportunistic behavior. Seasonal variations influenced the feeding pattern of the species, with greater feeding activity in the dry season. The considerable availability of resources in estuarine habitats of the western coast of Maranhão constitutes another factor that influences the feeding behavior of this species.

2015 ◽  
Vol 15 (2) ◽  
pp. 19-29
Author(s):  
Rastislava Stoličná

Abstract The study aims to describe the changes in public nutrition during the period of socialism in Slovakia. It explains the essence of the state Communist ideology’s involvement in people’s eating habits and the reality of food production, distribution and consumption.


2020 ◽  
Vol 16 (1) ◽  
Author(s):  
Haseeb Ul Rashid Masoodi ◽  
R. C. Sundriyal

Abstract Background Non-timber forest products (NTFPs) are important resources for sustenance of rural communities; a systematic planning to manage diverse NTFPs may immensely contribute to food and livelihood security of forest dwellers. Considering this, the present study has been undertaken in the Himachal Pradesh state in north India. It aims to provide detailed information on diversity, distribution, use pattern, and conservation status of selected NTFPs that have market potential, and suggest a possible way for their sustained management and possible role in livelihood upgradation of dependent communities. Methodology An inventory of NTFP species was prepared by collecting secondary information from published scientific studies in journals, books, and other periodicals as well as species being traded as per Forest department records. Search on various online databases were also used (Scopus, Google Scholar, PubMed, ISI Web of Science) using specific search terms such as “non-timber forest products,” “NTFPs,” “medicinal plants,” “wild edible plants,” and “Himachal Pradesh,” “Western Himalaya,” and “Northwest Himalaya.” A list of potential NTFPs was prepared having market value. To evaluate the relative usefulness of different species, a quantitative valuation was also used by calculating various indices, such as use value (UV), relative frequency of citation (RFC), relative importance index (RI), cultural importance index (CI), and cultural value (CV). Results A total of 811 species have been screened that has significant potential for the State, and categorized in 18 groups as per their use. The family use value was highest for Asteraceae (FUV = 76.75). Among plant parts used, whole plants, roots (including rhizomes and tubers), leaves, flowers, fruits, seeds, stems, and barks were used by the forest dwellers. Maximum NTFPs were collected from the warm temperate zone, followed by the temperate, sub-alpine, sub-tropical, and alpine zones. Sixty-one percent of species had medicinal importance, followed by species used for food and fodder purposes. Although species richness of medicinal plants decreased with altitude, however, most plants extracted from high altitudes were high-value species fetching better income. As many as 125 NTFPs were identified under the diverse level of threats according to IUCN criteria and as per the local stakeholders’ perceptions. Conclusion High dependence on NTFPs by poor and marginal communities for domestic needs as well as market demand of selected species leads to create excessive pressure on them. Unfortunately, the state agencies are not having any robust conservation plan for NTFPs. For long-term management of NTFPs sector, a species-specific conservation strategy, proper harvesting protocol, cultivation practices, the supply of quality planting material, product development and diversification, value chain development, and ensured market is greatly desired. This will not only lead to conserving NTFPs resources in their natural habitats but also lead a sustainable livelihood generation for forest dwellers.


2012 ◽  
Vol 90 (1) ◽  
pp. 128-132 ◽  
Author(s):  
Bradley R. Johnston ◽  
Markus Molis ◽  
Ricardo A. Scrosati

Nonconsumptive predator effects on prey behaviour are common in nature, but the possible influence of prey life-history stage on such responses is poorly known. We investigated whether prey life-history stage may be a factor affecting prey feeding activity responses to predator chemical cues, for which we used dogwhelks ( Nucella lapillus (L., 1758)) and their main prey, barnacles ( Semibalanus balanoides (L., 1758)), as a model system. Barnacles use their modified legs (cirri) to filter food from the water column. Through a manipulative laboratory experiment, we tested the hypothesis that the presence of dogwhelks affects the frequency of leg swipes differently in juvenile and adult barnacles. Juveniles showed a similar feeding activity with and without nearby dogwhelks, but adults exhibited a significantly lower frequency of leg swipes when dogwhelks were present. Such an ontogenetic change in the response of barnacles to predatory cues might have evolved as a result of dogwhelks preferring adult barnacles over juvenile barnacles, as found previously. Alternatively, barnacles could learn to recognize predator cues as they age, as shown for other prey species. Overall, our study indicates that the nonconsumptive effects of predators on prey need to be fully understood under consideration of the possible ontogenetic changes in prey responses to predator cues.


Author(s):  
P. Carpentieri ◽  
F. Colloca ◽  
G. Ardizzone

We investigated daily ration, feeding rhythms and gastric evacuation rates of juvenile (<16 cm total length) European hake Merluccius merluccius, using stomach samples collected during four 24-hour trawl surveys carried out in 2001–2002 on the continental shelf-break (from 120 m to 160 m in depth) off the western coast of central Italy (central Mediterranean Sea). In each survey 8 hauls of 30 minutes were performed every three hours throughout the 24-hour period to cover the entire diel cycle. Diet of juvenile hake was mostly composed of the euphausiid Nyctiphanes couchii, showing a peak in stomach contents during early morning followed by a daytime decrease. Fullness index (%FI) was generally higher during sunrise when migratory activity ceased and juvenile hake return to the bottom after feeding. Concerning the hake abundance the highest density value was obtained in May during the recruitment period.Two independent daily ration estimates were produced. First, an empirical attempt to estimate the daily amount of food consumed was obtained by back-calculating the fresh weight of euphausiid prey ingested by juvenile hake. Estimated values ranged from 4.96–5.89% body wet weight (%BW). Second, the daily ration was computed applying the exponential gastric evacuation models proposed by Elliot & Persson (1978) and Eggers (1979). Daily ration values obtained using these consumption models produced a considerable (15–20%) underestimation of consumption rate for juvenile hake.


2014 ◽  
Vol 26 (4) ◽  
pp. 381-391 ◽  
Author(s):  
Fabiane Silva Ferreira ◽  
Wagner Vicentin ◽  
Fábio Edir dos Santos Costa ◽  
Yzel Rondon Súarez

AIM: This study aimed to evaluate influence of hydrological variation, ontogeny and interspecific variation in the feeding activity and diet composition for P. nattereri and S. marginatus in floodplain of Negro River, South Pantanal. METHODS: The samples were taken with the use of gillnets and cast nets of different sizes, from October/2005 to August/2008. RESULTS: We sampled 748 specimens, 442 of P. nattereri and 306 of S. marginatus. We identified 31 items in the dry and 14 in the flood season for P. nattereri, and 29 items in the dry and eight in the flood season for S. marginatus. For both species, fish was the predominant food item in both seasons. The PERMANOVA results showed that the diet varied significantly between the two species (p<0.001), during ontogenetic development (p<0.001) and seasonally (p=0.024). The ancova results suggests that the intensity of food intake was higher in the dry season (p<0.001) for both species. The niche breadth varied only between studied species with S. marginatus presenting higher niche breadth than P. nattereri. CONCLUSION: Piranhas feed more during dry season, probably because in this period food is more varied and abundant, due to the concentration of fish in the main river channel. There were ontogenetic changes in the diet, with no feeding overlap between the two species, probably because of differences in preference for some items and differences in feeding behavior displayed during hunting attacks.


2010 ◽  
Vol 5 (6) ◽  
pp. 888-893 ◽  
Author(s):  
Andrea Novomeská ◽  
Vladimír Kováč ◽  
Stanislav Katina

AbstractThe study on the external morphology of the non-native black bullhead (Ameiurus melas) was carried out on a population from Slovakia, based on triple regression and geometrical analysis. The breakpoints distribution in distance-based morphometric characters indicated that black bullhead reached its definitive phenotype early in ontogeny. Ontogenetic changes in external morphology occurred continuously throughout the whole size-range of the sample examined, and inter-individual morphological variation was very low. Such uniformity may reflect the possible founder effect and/or little phenotypic plasticity of this non-native population. No sexual dimorphism was observed. This is the first detailed study on external morphology of the species, and as such it contributes to the assessment of phenotypic plasticity and/or overall morphological variability of black bullhead’s invasive populations.


2006 ◽  
Vol 63 (9) ◽  
pp. 1925-1933 ◽  
Author(s):  
M J Tremblay ◽  
S J Smith ◽  
D A Robichaud ◽  
P Lawton

Catchability (q) in traps was estimated for American lobsters (Homarus americanus) in Flagg Cove, off Grand Manan Island (New Brunswick, Canada), where large females (>100 mm carapace length (CL)) aggregate in late summer and early fall. In 2001 and 2002, diver surveys were used to estimate lobster density, and traps were then deployed to obtain catch rates. Bayesian generalized linear models were fit to the densities of different size groups (81–100, 101–130, 131–160, and >160 mm CL) of ovigerous females, non-ovigerous females, and males. Catchability was strongly affected by year. Differences in q due to sex and size for ovigerous females, non-ovigerous females, and males were apparent but were not consistent between years. Size was not an important factor for the catchability of lobsters between 81 and 160 mm CL. In comparison with lobsters of a similar size in other areas, Flagg Cove lobsters in the size range of 81–100 mm CL were less catchable. We hypothesize that this resulted from the high densities and larger sizes of lobsters in Flagg Cove, which likely lead to increased agonistic interactions and reduced entry of lobsters into traps.


1925 ◽  
Vol 62 (7) ◽  
pp. 309-319 ◽  
Author(s):  
C. E. Tilley

Chloritoid-Bearing schists have so far not been recorded from the State of South Australia, though such are known from the Pre-Cambrian rocks of the Broken Hill area. The chloritoid rocks now to be shortly described occur interbedded with quartzites, forming the meridional ridge of the “Frenchman”, on the western coast of southern Eyre Peninsula. In a previous paper (l)1 the rocks of this area have been referred to, as comprised within two groups, a sedimentary series—the Warrow series, and the Dutton series, a group of acid granites of gneissic habit with associated aplites and pegmatites, often rich in tourmaline and carrying garnet, and beryl. These rocks invade the sediments of the Warrow series.


2019 ◽  
Vol 99 (06) ◽  
pp. 1399-1408
Author(s):  
Paulo A. S. Costa ◽  
Adriana C. Braga ◽  
Giovanna S. Malavolti ◽  
Marcos A. L. Franco ◽  
Pedro V. Gatts ◽  
...  

AbstractStomach contents analysis and stable isotope results indicate M. hubbsi is a generalist predator that feeds mainly on demersal fishes, followed by crustaceans and cephalopods. Ontogenetic changes in diet were identified, with fish importance increasing in the diet with hake size. Smaller hake (&lt;250 mm) fed mostly on the sepiolid Semirossia tenera (89.45%IRI) and engraulid fish (89.96%IRI). Mid-sized hake (250–300 mm) fed mainly on benthic fish such as Bellator brachychir (95.63%IRI) and euphausiids (56.46%IRI), while larger hake (&gt;300 mm) fed heavily on Dactylopterus volitans (94.80%IRI) and occasionally on a variety of teleosts. Significant correlations between δ13C (P &lt; 0.05), THg (P &lt; 0.001) and hake size occurred, whereas no relationship was observed between δ15N and hake size or δ15N and total mercury. Signatures were lowest in smaller hake with a tendency of increasing with size. Smaller and larger hake were significantly different in δ13C. Differences regarding isotopic niche width were quantified for each size group; trophic diversity and trophic redundancy among them were negligible, but hake &gt;300 mm possibly have a larger feeding plasticity due to the combination of prey from a wide trophic level range.


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