Quantitative aspects of feeding of chaetognaths in the eastern Mediterranean pelagic waters

2003 ◽  
Vol 83 (3) ◽  
pp. 559-569 ◽  
Author(s):  
George Kehayias
Keyword(s):  
Eastern Mediterranean ◽  
Standing Stock ◽  
Gut Content Analysis ◽  
Ionian Sea ◽  
Gut Content ◽  
Sampling Area ◽  
Food Items ◽  
Total Food ◽  
The Mean ◽  
Pelagic Area

The diet of all chaetognath species found in a broad pelagic area of the eastern Mediterranean was investigated through gut content analysis. Eight chaetognath species were recovered from four depth intervals between 0 to 300 m in the Ionian, Cretan and Rhodes Seas and in the Cretan Passage. The mean food containing ratio (FCR) value for all chaetognaths combined was 0·048. Copepods comprised nearly 65% of the total food items consumed. The epipelagic species Sagitta enflata, Sagitta serratodentata atlantica, Sagitta bipunctata and Sagitta minima fed mainly in the 0 to 50 m surface layer, while the mesopelagic species Sagitta lyra, Sagitta decipiens, Sagitta hexaptera and Krohnitta subtilis fed in deeper layers. Sagitta s. atlantica showed the highest mean FCR in the integrated water column (0 to 300 m) of the whole sampling area. The estimated impact of chaetognath predation on copepod communities ranged from 0·3 to 7·8% of the copepod standing stock, and was higher in the Ionian Sea and the Cretan Passage than in the Cretan and Rhodes Seas. Sagitta s. atlantica, S. lyra, and S. decipiens had the most important predation impact among the eight chaetognath species found in the 0 to 50 m, 50 to 100 m and 100 to 300 m depth layers respectively.

scholarly journals Feeding Ecology Of Chironomus Larvae (Insecta: Diptera) Collected From Different Habitat of Dhaka, Bangladesh

2012 ◽  
Vol 40 (1) ◽  
pp. 129-133 ◽  
Author(s):  
M Niamul Naser ◽  
Dulon Roy
Keyword(s):  
Feeding Habits ◽  
Feeding Activity ◽  
Food Selection ◽  
Single Species ◽  
Gut Content Analysis ◽  
Gut Content ◽  
Feeding Intensity ◽  
Chironomid Larvae ◽  
Food Items ◽  
Low Degree

Chironomid larvae are frequently available in the muddy habitats of Curzon Hall campus of University of Dhaka. The larvae of single species of  Chironomus (Insecta: Diptera) were collected from the drains and pond of the campus. Algae, fungi, diatoms, protozoan’s, rotifers, animal parts (crustacean appendages, ostracodan shell, insect appendages), and detritus were found as the  main food items of the larvae. Gut content analysis showed a change in their  feeding habits with seasons. The feeding intensity was maximum in spring just after winter. The feeding activity was lowest in winter. The variation in the diet  may suggest that these groups showed a low degree of selectivity, having more  generalist food selection habit. DOI: http://dx.doi.org/10.3329/bjz.v40i1.12902 Bangladesh J. Zool. 40(1): 129-133, 2012

scholarly journals Ventilation of the Mediterranean Sea constrained by multiple transient tracer measurements

Ocean Science ◽  
2014 ◽  
Vol 10 (3) ◽  
pp. 439-457 ◽  
Author(s):  
T. Stöven ◽  
T. Tanhua
Keyword(s):  
Deep Water ◽  
Eastern Mediterranean ◽  
Western Mediterranean ◽  
Inverse Gaussian ◽  
Ionian Sea ◽  
One Dimensional ◽  
Levantine Basin ◽  
The Mean ◽  
The Mediterranean ◽  
Transient Tracer

Abstract. Ventilation is the primary pathway for atmosphere–ocean boundary perturbations, such as temperature anomalies, to be relayed to the ocean interior. It is also a conduit for gas exchange between the interface of atmosphere and ocean. Thus it is a mechanism whereby, for instance, the ocean interior is oxygenated and enriched in anthropogenic carbon. The ventilation of the Mediterranean Sea is fast in comparison to the world ocean and has large temporal variability. Here we present transient tracer data from a field campaign in April 2011 that sampled a unique suite of transient tracers (SF6, CFC-12, 3H and 3He) in all major basins of the Mediterranean. We apply the transit time distribution (TTD) model to the data in order to constrain the mean age, the ratio of the advective / diffusive transport and the number of water masses significant for ventilation. We found that the eastern part of the eastern Mediterranean can be reasonably described with a one-dimensional inverse Gaussian TTD (IG-TTD), and thus constrained with two independent tracers. The ventilation of the Ionian Sea and the western Mediterranean can only be constrained by a linear combination of IG-TTDs. We approximate the ventilation with a one-dimensional, two inverse Gaussian TTD (2IG-TTD) for these areas and demonstrate a possibility of constraining a 2IG-TTD from the available transient tracer data. The deep water in the Ionian Sea has a mean age between 120 and 160 years and is therefore substantially older than the mean age of the Levantine Basin deep water (60–80 years). These results are in contrast to those expected by the higher transient tracer concentrations in the Ionian Sea deep water. This is partly due to deep water of Adriatic origin having more diffusive properties in transport and formation (i.e., a high ratio of diffusion over advection), compared to the deep water of Aegean Sea origin that still dominates the deep Levantine Basin deep water after the Eastern Mediterranean Transient (EMT) in the early 1990s. The tracer minimum zone (TMZ) in the intermediate of the Levantine Basin is the oldest water mass with a mean age up to 290 years. We also show that the deep western Mediterranean has contributed approximately 40% of recently ventilated deep water from the Western Mediterranean Transition (WMT) event of the mid-2000s. The deep water has higher transient tracer concentrations than the mid-depth water, but the mean age is similar with values between 180 and 220 years.

scholarly journals Ventilation of the Mediterranean Sea constrained by multiple transient tracer measurements

2013 ◽  
Vol 10 (5) ◽  
pp. 1647-1705 ◽  
Author(s):  
T. Stöven ◽  
T. Tanhua
Keyword(s):  
Mediterranean Sea ◽  
Deep Water ◽  
Eastern Mediterranean ◽  
Western Mediterranean ◽  
Inverse Gaussian ◽  
Ionian Sea ◽  
Levantine Basin ◽  
The Mean ◽  
The Mediterranean ◽  
Transient Tracer

Abstract. Ventilation is the prime pathway for ocean surface perturbations, such as temperature anomalies, to be relayed to the ocean interior. It is also the conduit for gas exchange between atmosphere and ocean and thus the mechanism whereby, for instance, the interior ocean is oxygenated and enriched in anthropogenic carbon. The ventilation of the Mediterranean Sea is fast in comparison to the world ocean and has large temporal variability, so that quantification of Mediterranean Sea ventilation rates is challenging and very relevant for Mediterranean oceanography and biogeochemistry. Here we present transient tracer data from a field-campaign in April 2011 that sampled a unique suite of transient tracers (SF6, CFC-12, tritium and 3He) in all major basins of the Mediterranean. We apply the Transit Time Distribution (TTD) model to the data which then constrain the mean age, the ratio of the advective/diffusive transport mechanism, and the presence, or not, of more than one significant (for ventilation) water mass. We find that the eastern part of the Eastern Mediterranean can be reasonable described with a one dimensional Inverse Gaussian (1IG) TTD, and thus constrained with two independent tracers. The ventilation of the Ionian Sea and the Western Mediterranean can only be constrained by a multidimensional TTD. We approximate the ventilation with a two-dimensional Inverse Gaussian (2IG) TTD for these areas and demonstrate one way of constraining a 2IG-TTD from the available transient tracer data. The deep water in the Ionian Sea has higher mean ages than the deep water of the Levantine Basin despite higher transient tracer concentrations. This is partly due to the deep water of Adriatic origin having more diffusive properties in the transport and formation, i.e. a high ratio of diffusion over advection, compared to the deep water of Aegean Sea origin that still dominates the deep Levantine Basin deep water after the Eastern Mediterranean Transient (EMT) in the early 1990s. We also show that the deep Western Mediterranean has approximately 40% contribution of recently ventilated deep water from the Western Mediterranean Transition (WMT) event of the mid-2000s. The deep water has higher transient tracer concentrations than the mid-depth water, but the mean age is similar.

scholarly journals Studies on Tropics of Fish Along Upper Tungabhadra Channel, Ballari District, Karnataka

2020 ◽  
Vol 15 (3) ◽  
pp. 601-606
Author(s):  
A. R. Kulkarni
Keyword(s):  
Fisheries Management ◽  
Fish Nutrition ◽  
Relative Importance ◽  
Gut Content Analysis ◽  
Gut Content ◽  
Food Items ◽  
Irrigation Channel ◽  
Channel Water ◽  
Gut Analysis ◽  
Aquatic Food

Gut analysis is the tool to understand the feeding patterns of fishes and is an important aspect of fisheries management. It also provides the basis for understanding trophic interactions in aquatic food webs and to investigate the most frequently consumed prey or to determine the relative importance of different food types to fish nutrition. In the present study the gut content analysis was performed in Garra, Gobi, Notopterus and Tilapia fishes collected from Tungabhadra upper irrigation channel at Ballari, Karnataka.Bacillariophyceae showed maximum number in all the four fish species. Over all it showed 40% followed by Detritus (30%), Chlorophyceae (17%), Cyanophyceae(7%) and Zooplankton (6%). Among fishes Garrashowed maximum food items (2272) followed by Glossogobiusgiuris(1538), Notopterusnotopterus (996) and Oreochromismossambicus (769). The relative abundance of food items in the guts also revealed the Garragotylastenorhynchus Oreochromismossambicus. The variation is due to availability of foodorganisms during the study period and anthropogenic influence on channel water.

scholarly journals Insights on diet dynamics of Indian mackerel Rastrelliger kanagurta (Cuvier, 1816)

2020 ◽  
Vol 67 (3) ◽  
Author(s):  
U Ganga ◽  
C. K. Radhakrishnan
Keyword(s):  
Monsoon Season ◽  
Rank Correlation ◽  
Diet Breadth ◽  
Gut Content Analysis ◽  
Gut Content ◽  
Spearman Rank Correlation ◽  
Indian Mackerel ◽  
Food Items ◽  
Size Groups ◽  
Rastrelliger Kanagurta

The diet of Indian mackerel Rastrelliger kanagurta (Cuvier, 1816) is reported based on the gut content analysis of specimens collected along the central Kerala coast, India. The study indicated ontogenetic variations in diet with diet breadth being highest in the largest size class of >231 mm total length (TL). Copepods followed by diatoms were the preferred food items. Detritus was an important diet component, especially during the pre-monsoon season and in the larger (>231 mm TL) size groups. The Preponderal Index (Ip) indicated seasonal differences in proportions of the various prey consumed. Spearman Rank Correlation Coefficient indicated similar diet quality during monsoon (June-September) and post-monsoon (October-January) seasons; but significant differences as compared to pre-monsoon season (February-May). Based on the results of the study, Indian mackerel was classified as an opportunistic feeder with a diet component that broadly reflects its seasonal-spatial habitats and local food availability.

Analisis Isi Lambung Ikan Selais Terang Bulan (Kryptopterus bicirrhis, Valenciennes 1840) Di Desa Rantau Kasih Sungai Kampar Kiri Propinsi Riau

Biospecies ◽  
2018 ◽  
pp. 57-63
Author(s):  
Ermi Yeni ◽  
Roza Elvyra
Keyword(s):  
Content Analysis ◽  
Gut Content Analysis ◽  
Gut Content ◽  
Additional Food ◽  
Male And Female ◽  
Carnivorous Fish ◽  
Supplementary Food ◽  
Main Food

The study on gut content of Selais Terang Bulan fish (Kryptopterus bicirrhis) in Rantau Kasih village Kampar Kiri river was conducted from Februari- April 2017. The purpose of this study was to know about gut content of Selais Terang Bulan fish which was categorized as main food, supplementary food and additional food. The analysis is done based on the instruction of Natardjan and Jhingran (1961). The gut content was analized using the Index of preponderance.  The result revealed that  the main food of  Selais Terang Bulan fish in Rantau Kasih village is adult Arthropoda with IP value (78.85%), and supplementary food is caterpillar (25.15%). Male and female fishes at have main food of adult Arthropoda with different percentages are (82.81%) male and female (71.32%). Based on the gut content analysis of Selais Terang Bulan fish was a carnivorous fish.

scholarly journals Comparative gut content analysis of invasive mosquitofish from Italy and Spain

2021 ◽  
Author(s):  
Sara Pirroni ◽  
Laura Pennafort Dezen ◽  
Francesco Santi ◽  
Rüdiger Riesch
Keyword(s):  
Content Analysis ◽  
Gut Content Analysis ◽  
Gut Content

Detecting Specific Resource Use by Drosophila suzukii (Diptera: Drosophilidae) Using Gut Content Analysis

2018 ◽  
Vol 111 (3) ◽  
pp. 1496-1500 ◽  
Author(s):  
Lauren M Diepenbrock ◽  
Jonathan G Lundgren ◽  
Tim L Sit ◽  
Hannah J Burrack
Keyword(s):  
Content Analysis ◽  
Resource Use ◽  
Gut Content Analysis ◽  
Gut Content ◽  
Drosophila Suzukii
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