scholarly journals First data on habitat preference, diet and length-weight relationship of Gobius incognitus Kovačić & Šanda, 2016 (Pisces: Gobiidae)

2020 ◽  
Vol 61 (1) ◽  
pp. 67-78
Author(s):  
Francesco Tiralongo ◽  
Giuseppina Messina ◽  
Bianca Maria Lombardo

In this work, we present first data on biological and ecological aspects of Gobius incognitus from specimens from the Ionian Sea (central Mediterranean Sea). In particular, we provided first data on habitat preference, diet and length-weight relationship of G. incognitus on material with confirmed species identity. The species preferred “mixed bottom” (sand and rocks), where it reached relatively high abundances. The diet analysis showed that G. incognitus is a generalist and opportunistic feeder. However, small benthic crustaceans were the most important prey group. The mean total length of specimens was 6.72 ± 1.85 cm and the growth was positive allometric.

2020 ◽  
Vol 8 (4) ◽  
pp. 269
Author(s):  
Francesco Tiralongo ◽  
Giuseppina Messina ◽  
Bianca Maria Lombardo

Data on the biology of Dasyatis pastinaca are absent from the Ionian Sea and only a few studies were conducted in the Mediterranean Sea. Some biological and ecological aspects of D. pastinaca were investigated between November 2019 and February 2020 in the central Mediterranean Sea. In particular, we investigated several morphologic, population and ecological aspects of the species. The analysis of the stomach contents showed that D. pastinaca is a generalist carnivorous, mainly feeding on small crustaceans and polychaetes. The Levin’s index value (Bi) was 0.85. The sex ratio showed no significant differences from 1:1 ratio. Females were larger than males, but no statistical differences were found in disc width-weight and total length-disc width relationships between sexes. Most of the specimens caught were juveniles and inhabit shallow sandy bottoms.


2021 ◽  
Vol 6 (1) ◽  
pp. 116-124
Author(s):  
Nur Asia Nasution ◽  
Rusdi Machrizal

The existence of gold mining activities in mailil river can disrupt the stability of the ecosystem, fishing by using toxins, which may result in a decrease in fish populations in the river mailil. This study aims to obtain information related to biological and ecological aspects (Barbonymus gonionotus) in river Mailil, Village. This study was conducted from November 2020 to January 2021. The locations for sampling were determined based on information from the local community in Bandar Kumbul Village. Samples were caught using nets, traps, and nets Sampling was conducted from 09:00 am to 03:00 pm. The biological aspect being measured was the length-weight relationship of the fish using the linear allometric model (LAM). Meanwhile, the ecological aspect being measured was the condition factor using Fulton’s K equation and relative weight (Wr) equation. In this study, 54 silver barbs (B. gonionotus) were successfully caught as samples. The results of the length-weight relationship analysis indicated a negative allometric relationship with the value of b = 0.52 (b < 3). Furthermore, the value of Fulton’s K condition factor was 27.75, while the value of relative weight (Wr) condition factor was 100.07. These results indicated that river Mailil as an ecosystem and habitat of silver barbs is in the balance condition.Keywords: Length-weight relationship, Barbonymus gonionotus, aek mailil


2016 ◽  
Vol 40 (1) ◽  
pp. 57-64 ◽  
Author(s):  
Mohammed Sadequer Rahman ◽  
Mohammad Mizanur Rahman ◽  
Md Sohel Parvez ◽  
Md. Rashed Un Nabi

Diet analysis revealed that Apocryptes bato is a carnivorous fish. It depends on shrimps and non-shrimp crustaceans mainly. Shrimps include Acetes, penaeid and metapenaeid juveniles, whereas non-shrimp crustaceans include copepods, crab larvae, mysids and amphipods predominantly. The total body lengths (TL) varied between 11.20 and 22.20 cm and weight 16.70 to 43.50 g in male fish. The form of the equation for TL and weight relationship was W = 0.44TL2.57 and for standard length (SL) it was W = 1.009SL2.66. Condition factor (K) ranged from 0.87 to 1.23. The TL was 15.00 to 26.00 cm and weight as 25.1 to 38.50 g in female. The equation was W = 1.001TL2.52 for TL and W = 1.003SL2.63 for SL and K value ranged from 0.95 to 1.106. The coefficient of correlation was tested with t test and found highly significant at the 5% level of significance for TL and SL both in the case of male and female.Journal of Bangladesh Academy of Sciences, Vol. 40, No. 1, 57-64, 2016


2013 ◽  
Vol 3 (2) ◽  
pp. 37 ◽  
Author(s):  
Retno Andamari ◽  
David Milton ◽  
Thohir Zubaidi

The reproductive biology of five species of anchovies (Encrasicholina and Stolephorus) in Bima Bay, Nusa Tenggara, Indonesia was examined and  compared with previous studies of the same species in Bacan, Maluku and other parts of Indonesia. Fish and plankton sampling was conducted in February and April 2000. The length and weight relationship of five species of anchovies had a slope (b) that ranged from 2.71 to 3.74. These values were less than those found in Bacan for the same species. All species were multiple spawner and the mean batch fecundity ranged between 1226 (Encrasicholina devisi) and 2470 (E. punctifer). Relative fecundity varied among the species inversely with size, being lower in the larger species. Age at first spawning varied from 67 to 141 days for all five species and was higher in Stolephorus species. Lifetime egg production was less than that found in Bacan for the same species, but similar to that found in similar habitats elsewhere in the tropical Indo-Pacific. These results suggest that anchovy egg production is higher, but more variable in open oceanic environments compared with the more stable, coastal bays.


2021 ◽  
Vol 9 (7) ◽  
pp. 686
Author(s):  
Angela Carluccio ◽  
Francesca Capezzuto ◽  
Porzia Maiorano ◽  
Letizia Sion ◽  
Gianfranco D’Onghia

Baited lander represents a low impact technique, an alternative to the traditional trawl sampling for collecting data on fish diversity and abundance, especially for threatened species such as Chondrichthyes living in sensitive habitats. In this study, distribution and abundance of cartilaginous fish were compared between two geographic areas, the southern Adriatic Sea and the north-western Ionian Sea, with two low impact sampling gears, an experimental bottom longline and a baited lander. Species diversity was evaluated by applying ecological indices and difference in mean abundances were tested using multivariate analysis. A total of 13 species of cartilaginous fish were collected. Significant differences in the assemblage recorded in the same area using different sampling tools were detected and no significant differences were detected among different areas explored with the same method. Using longline, the most abundant species collected in both areas was Galeus melastomus, while using lander, the most observed species were Dalatias licha in the southern Adriatic Sea and Hexanchus griseus in the north-western Ionian Sea. According to IUCN classification, of the 13 species collected, 2 are near threatened and 5 are threatened. A better governance of sensitive habitats coinciding with the essential fish habitat for these species would ensure them a better conservation status.


1970 ◽  
Vol 30 (2) ◽  
pp. 583-587 ◽  
Author(s):  
Albert V. Carron

The present report is based on reanalysis of data of Marisi (1969) in order to examine the relationship of consistency of motor response among the component responses of a single motor task. 120 high school Ss were tested on a special task, the rho. A single trial on this motor task can be logically separated into three component motor responses: reaction time, a short circular movement, and a short linear movement. The results indicated that consistency of motor response was moderately reliable within the response components but tended to be response-component specific. Further, both the reliability and specificity of motor-response consistency were independent of the size of the mean performance scores.


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