Reliability in Measuring Diet Overlap

1983 ◽  
Vol 40 (3) ◽  
pp. 347-351 ◽  
Author(s):  
Richard K. Wallace ◽  
John S. Ramsey
Keyword(s):  
Sample Size ◽  
Confidence Limit ◽  
High Reliability ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Diet Overlap ◽  
Volume Percentage ◽  
Upper Confidence Limit ◽  
Menidia Beryllina ◽  
Collection Date

Intraspecific diet overlaps were calculated for young-of-the-year largemouth bass (Micropterus salmoides), juvenile bluegills (Lepomis macrochirus), and inland silversides (Menidia beryllina) by randomly dividing collections of each species into two sets, measuring the diet (average of the volume percentage) and calculating the diet overlap by Schoener's method. The randomization process and overlap calculation were repeated 30 times and an upper confidence limit (95%) for intraspecific overlap was determined. Upper confidence limits of intraspecific overlap were generally below the 100% overlap expected if diets were adequately characterized. Intraspecific overlap varied with collection date, fish species, and size of sample. Increasing sample size did not increase intraspecific overlap when the larger sample included a wider size range of fish. The upper confidence limit of intraspecific overlap can be used as a measure of reliability for interspecific diet overlap calculations. We suggest that intraspecific overlaps approaching 100% indicate high reliability for the corresponding interspecific overlap value. The intraspecific overlap is most useful in judging the reliability of interspecific overlap when sample size is limited.Key words: diet overlap, intraspecific overlap, interspecific overlap

scholarly journals Effect of the Human Utilization of Northern Snakehead (Channa argus Cantor, 1842) on the Settlement of Exotic Fish and Cladoceran Community Structure

2021 ◽  
Vol 13 (5) ◽  
pp. 2486
Author(s):  
Jong-Yun Choi ◽  
Seong-Ki Kim
Keyword(s):  
Community Structure ◽  
Fish Species ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Nakdong River ◽  
Exotic Fish ◽  
Carnivorous Fish ◽  
Channa Argus ◽  
The Nakdong River ◽  
Exotic Fish Species

Empirical studies suggest that changes in the density of top predators, such as carnivorous fish, in freshwater food webs, strongly affect not only fish communities but also various primary and secondary consumers. Based on these findings, we explored how differences in the utilization of carnivorous fish (i.e., Northern Snakehead, Channa argus) by humans affected the fish and cladoceran community structure as well as the settlement of exotic fish species (i.e., Lepomis macrochirus and Micropterus salmoides) in 30 wetlands located in the upper and lower reaches of the Nakdong River. Our results show that in the mid–lower reaches of the Nakdong River, the density of C. argus was low, while high densities of L. macrochirus and M. salmoides were observed. Exotic fish species are frequently consumed by C. argus, leading to a low density of L. macrochirus and M. salmoides in the upper reaches, which supported a high density of C. argus. However, in the mid–lower reaches, the density of L. macrochirus was high because of the frequent collection of C. argus by fishing activities. The dominance of L. macrochirus significantly changed the structure of cladoceran communities. L. macrochirus mainly feeds on pelagic species, increasing the density of epiphytic species in the mid–lower reaches. The continued utilization of C. argus by humans induced a stable settlement of exotic fish species and strongly affected the community structures of primary consumers in the 30 wetlands. The frequency of C. argus collection has to be reduced to secure biodiversity in the mid–lower reaches of the Nakdong River, which will reduce the proportion of exotic fish species and increase the conservation of native fish.

Quantitative comparisons of the morphology and ultrastructure of erythrocyte nuclei from seven freshwater fish species

1995 ◽  
Vol 73 (10) ◽  
pp. 1951-1959 ◽  
Author(s):  
Charles H. Jagoe ◽  
Dave A. Welter
Keyword(s):  
Fish Species ◽  
Yellow Perch ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Nuclear Size ◽  
Image Analysis System ◽  
Cell Nuclei ◽  
Homogeneous Population ◽  
Differentiated Cells ◽  
Rainbow Trout Oncorhynchus Mykiss

Chromosome number and genomic DNA content vary widely among fish species, and ploidy can vary within species. This suggests that the size, shape, and morphological features of cell nuclei may also vary. Nucleated erythrocytes of fish are an easily sampled homogeneous population of differentiated cells ideal for inter- and intra-species comparisons. We collected blood samples from largemouth bass (Micropterus salmoides), bluegill (Lepomis macrochirus), chain pickerel (Esox niger), yellow perch (Perca flavescens), mosquitofish (Gambusia holbrooki), redeye bass (Micropterus coosae), and rainbow trout (Oncorhynchus mykiss) and removed cytoplasm and nuclear membranes from blood cells. Individual nuclei were examined and measured using scanning electron microscopy and a computerized image analysis system, and inter- and intra-species differences evaluated by nested analysis of variance. Nuclear size and shape varied significantly among species. Isolated nuclei had conspicuous apertures or holes, and the number and size of these holes also varied significantly among species. Variations in nuclear size and structure within species were small compared with interspecies differences. Little is known of the ultrastructure of erythrocyte nuclei in lower vertebrates, but their structure differs considerably from that of other vertebrate non-erythroid cells, suggesting that the organization of their DNA and associated proteins may be different.

scholarly journals Freshwater fishes of Bontebok National Park

Koedoe ◽  
2001 ◽  
Vol 44 (2) ◽  
Author(s):  
I.A. Russell
Keyword(s):  
South African ◽  
National Park ◽  
Fish Assemblages ◽  
Micropterus Salmoides ◽  
Clarias Gariepinus ◽  
Lepomis Macrochirus ◽  
River System ◽  
Indigenous Species ◽  
Freshwater Species ◽  
Micropterus Dolomieu

Fish assemblages were sampled at six sites in the Breede River in the Bontebok National Park during 1999 and 2000. A total of 380 fish from 12 species was recorded. Indigenous fish collected included one freshwater species (Barbus andrewi), two catodromous species (Anguilla mossambica, Myxus capensis). and three estuarine species (Gilchris- tella aestuaria, Monodactylusfalciformis, Mugil cephalus). Four of the species recorded were aliens (Tinea tinea, Lepomis macrochirus, Micropterus salmoides, Micropterus dolomieu) and two species translocated from other South African rivers (Tilapia sparrmanii, Clarias gariepinus). A further two indigenous species (Sandelia capensis, Pseudobarbus biirchelli) could potentially occur within the park, though the high abundance of alien predators means that there is little chance for recolonisation from tributaries higher in the Breede River system. There is little opportunity to meaningfully conserve most indigenous freshwater fish in Bontebok National Park.

scholarly journals The peril of adjusting for baseline when using change as a predictor

2019 ◽  
Author(s):  
Kimmo Sorjonen ◽  
Daniel Falkstedt ◽  
Bo Melin ◽  
Michael Ingre
Keyword(s):  
High Risk ◽  
Sample Size ◽  
Simulation Study ◽  
Strong Correlation ◽  
High Reliability ◽  
Large Sample Size ◽  
Present Simulation ◽  
Very High ◽  
Time Point

Some studies have analyzed the effect of a predictor measured at a later time point (X1), or of the X1-X0 difference, while adjusting for the predictor measured at baseline (X0), on some outcome Y of interest. The present simulation study shows that, if used to analyze the effect of change in X on Y, there is a high risk for this analysis to produce type 1-errors, especially with a strong correlation between true X and Y, when X0 and X1 are not measured with very high reliability, and with a large sample size. These problems are not encountered if analyzing the unadjusted effect of the X1-X0 difference on Y instead, and as this effect exhibits power on par with the adjusted effect it seems as the preferable method when using change between two measurement points as a predictor.

Historical Changes in Large River Fish Assemblages of the Americas

2005 ◽  
Keyword(s):  
Relative Abundance ◽  
Mississippi River ◽  
Largemouth Bass ◽  
Fish Assemblage ◽  
Fish Assemblages ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Large River ◽  
Frequency Of Occurrence ◽  
Abundance And Distribution

<em>Abstract.</em>—An investigation of historical fisheries information for pools 4–13 of the upper Mississippi River (UMR) was conducted to 1) determine the pre-1938 relative abundance and distribution of bluegill <em>Lepomis macrochirus </em>and largemouth bass <em>Micropterus salmoides, </em>2) determine the composition and relative abundance of the preimpoundment fish assemblage, and 3) determine if a shift in frequency of occurrence and relative abundance has occurred due to impoundment.

scholarly journals Bifunctional Role of the Sternohyoideus Muscle During Suction Feeding in Striped Surfperch, Embiotoca lateralis

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
J J Lomax ◽  
T F Martinson ◽  
Y E Jimenez ◽  
E L Brainerd
Keyword(s):  
Muscle Mass ◽  
Muscle Power ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Muscle Length ◽  
Muscle Size ◽  
Suction Feeding ◽  
Shortening Velocity ◽  
Axial Muscle ◽  
Embiotoca Lateralis

Synopsis In ray-finned fishes, the sternohyoideus (SH) is among the largest muscles in the head region and, based on its size, can potentially contribute to the overall power required for suction feeding. However, the function of the SH varies interspecifically. In largemouth bass (Micropterus salmoides) and several clariid catfishes, the SH functions similarly to a stiff ligament. In these species, the SH remains isometric and transmitts power from the hypaxial musculature to the hyoid apparatus during suction feeding. Alternatively, the SH can shorten and contribute muscle power during suction feeding, a condition observed in the bluegill sunfish (Lepomis macrochirus) and one clariid catfish. An emerging hypothesis centers on SH muscle size as a predictor of function: in fishes with a large SH, the SH shortens during suction feeding, whereas in fish with a smaller SH, the muscle may remain isometric. Here, we studied striped surfperch (Embiotoca lateralis), a species in which the SH is relatively large at 8.8% of axial muscle mass compared with 4.0% for L. macrochirus and 1.7% for M. salmoides, to determine whether the SH shortens during suction feeding and is, therefore, bifunctional—both transmitting and generating power—or remains isometric and only transmits power. We measured skeletal kinematics of the neurocranium, urohyal, and cleithrum with Video Reconstruction of Moving Morphology, along with muscle strain and shortening velocity in the SH and epaxial muscles, using a new method of 3D external marker tracking. We found mean SH shortening during suction feeding strikes (n = 22 strikes from four individual E. lateralis) was 7.2 ± 0.55% (±SEM) of initial muscle length. Mean peak speed of shortening was 4.9 ± 0.65 lengths s−1, and maximum shortening speed occurred right around peak gape when peak power is generated in suction feeding. The cleithrum of E. lateralis retracts and depresses but the urohyal retracts and depresses even more, a strong indicator of a bifunctional SH capable of not only generating its own power but also transmitting hypaxial power to the hyoid. While power production in E. lateralis is still likely dominated by the axial musculature, since even the relatively large SH of E. lateralis is only 8.8% of axial muscle mass, the SH may contribute a meaningful amount of power given its continual shortening just prior to peak gape across all strikes. These results support the finding from other groups of fishes that a large SH muscle, relative to axial muscle mass, is likely to both generate and transmit power during suction feeding.

Feeding Biology of the Black Crappie, Pomoxis nigromaculatus

1968 ◽  
Vol 25 (2) ◽  
pp. 285-297 ◽  
Author(s):  
Allen Keast
Keyword(s):  
Body Length ◽  
Micropterus Salmoides ◽  
Lepomis Macrochirus ◽  
Insect Larvae ◽  
Progressive Change ◽  
Pomoxis Nigromaculatus ◽  
Feeding Biology ◽  
Ambloplites Rupestris ◽  
Gill Raker ◽  
Diptera Larvae

In Lake Opinicon, Ontario, the diet of the black crappie, Pomoxis nigromaculatus, undergoes a progressive change from one in which planktonic Crustacea and small-bodied Diptera larvae predominate (in fish of body length from about 60 to 115 mm), to a diet of insect larvae and fish (in fish 160–240 mm). Most food items prove to be midwater forms and the Diptera larvae are almost entirely Chaoborus and Procladius, which are free-swimming in the water column at night.An unusual feature is the prolonged nature of the Cladocera-Copepoda eating phase, which continues into year III and to a body length of about 160 mm. Gill-raker counts show P. nigromaculatus to have a specialized screen with 25–29 rakers on the first arch. In this it differs from cohabiting centrarchids in Lake Opinicon, Ambloplites rupestris, Micropterus salmoides, and Lepomis macrochirus, in which the rakers on the first arch number only 8–12. In these species plankton feeding is restricted to the earlier stages.

The Experiment for the Fracture Toughness of the Compound Bioceramic and the Analysis for the Confidence Level of its Reliability

2010 ◽  
Vol 44-47 ◽  
pp. 3003-3010
Author(s):  
Shi Lian Xu ◽  
Rui Hong Wang ◽  
Ruo Qi Li ◽  
Ren Ping Xu
Keyword(s):  
Experimental Data ◽  
Fracture Toughness ◽  
Confidence Level ◽  
Confidence Limit ◽  
Limit Curve ◽  
Medical Treatments ◽  
Manufacturing Method ◽  
Upper Confidence Limit ◽  
Lower Confidence ◽  
Two Parameter

The brittle is crippling the application of bioceramic. The compound bioceramic is a new biomaterial being widely applied in medical treatments and its fracture toughness is an important mechanical behaviors. In this paper, we introduce the manufacturing method of the compound bioceramic and experiment facilities for its fracture toughness, investigate its probability distribution for the experimental data and conduct the test for fit. We conclude that the experimental data for the toughness fracture of the compound bioceramic obey the two-parameter Weibull distribution, introduce the analyzing method for the upper confidence limit curve and lower confidence limit curve and study the reliability and confidence level of the fracture toughness of the compound bioceramic.

Sign in / Sign up

Export Citation Format

Share Document