scholarly journals Analysis of some biological aspects of the Blue-spotted tilapia, Oreochromis leucostictus (Trewavas, 1933) in Lake Naivasha, Kenya

2020 ◽  
Author(s):  
Cishahayo Laurent ◽  
Edwine Yongo ◽  
Edna Waithaka ◽  
Eunice Mutethya
Keyword(s):  
Sex Ratio ◽  
Growth Condition ◽  
Condition Factor ◽  
Lake Naivasha ◽  
Weight Relationship ◽  
Total Length ◽  
Fish Samples ◽  
Commercially Important ◽  
Biological Aspects ◽  
The Mean

Oreochromis leucostictus is one of the commercially important tilapiine in Lake Naivasha. Its stock in the lake has declined due to the effect of fishing and pollution. This study investigated on its length-weight relationship, condition factor, sex ratio and maturity. Fish samples (233) were caught using gillnets of mesh-sizes 2-5 inches. Each individual fish was measured (cm) and weighed (g) in the field. The specimens were preserved in ice and transported to the laboratory for analysis of maturity. The mean (±SE) total length and weight for all fish was 21.3±0.3 cm TL and 187.4±8.3 g, respectively. Males 22.3±0.4 cm were significantly larger than females 19.2±0.5 cm. The mean condition factor was 1.06, 0.99 and 1.04 for male, female and combined sexes, respectively. The overall population sex ratio was 2.19:1.0 (male: female) that deviated significantly from 1:1. The slope b of the length-weight relationship was 1.92, 3.07, 2.33 for males, females, and combined sexes, respectively. Length at 50% maturity was estimated at 21.0 cm for females and 26.0 cm for males. Ripe oocytes and testis were found in all fish sizes. Comparisons with earlier studies suggest that the parameters of its growth, condition and maturity vary greatly from the different habitats.

scholarly journals Hubungan panjang bobot dan faktor kondisi ikan wader bintik dua Barbodes binotatus (Valenciennes, 1842) di Sungai Barambai Samarinda Kalimantan

2019 ◽  
Vol 18 (2) ◽  
pp. 87 ◽  
Author(s):  
. Jusmaldi ◽  
Nova Hariani
Keyword(s):  
Sex Ratio ◽  
Condition Factor ◽  
Mean Value ◽  
Male And Female ◽  
Weight Relationship ◽  
Total Length ◽  
East Kalimantan ◽  
Fish Samples

Biology of the spotted barb Barbodes binotatus (Valenciennes, 1842) in Barambai River, east Kalimantan is unknown. This study aimed to analyses sizes of fish, sex ratio, length-weight relationship and condition factor of the spotted barb. A total of 347 fish samples were collected by several gears in Barambai River from August to October 2017. The results of this research showed that the total length of the fish ranged from 45.67 to 146.01 mm and weight ranged from 1.27-43.34 g. The sex ratio of male and female were 1:1.12. The length-weight equations for males was W = 1x10-5 L3.063, W = 8x10-6L3.108 for females, and W = 9 x 10-6 L3.091 for both sexes. The condition factor (K) for the spotted barb was ranged between 0.826 – 2.214 with mean value of 1.163.  AbstrakBiologi ikan wader bintik dua Barbodes binotatus (Valenciennes, 1842) di Sungai Barambai, Kalimantan Timur belum diketahui. Penelitian ini bertujuan menganalisis ukuran ikan, nisbah kelamin, hubungan panjang bobot, dan faktor kon-disi. Total 347 sampel ikan dikumpulkan dengan menggunakan berbagai alat tangkap di Sungai Barambai dari bulan Agustus sampai Oktober 2017. Hasil penelitian menunjukkan bahwa panjang total ikan berkisar dari 45,67 sampai 146,01 mm dan bobot tubuh berkisar 1,27- 43,34 gram. Nisbah kelamin jantan dan betina 1: 1,12. Model hubungan panjang bobot ikan jantan W = 1x10-5 L3,063, ikan betina W = 8x10-6L3,108,dan keseluruhan jenis ikan W =  9 x 10-6  L3,091. Faktor kondisi (K) ikanwader bintik dua berkisar antara 0,826 - 2,214 dan rata-rata 1,163. 

Understanding selected growth aspects in Redbelly Tilapia, Coptodon zilli (Gervais) and Largemouth Bass, Micropterus salmoides (Lacepède) in Lake Naivasha, Kenya; Fisheries Management Perspective

2020 ◽  
Vol 01 (01) ◽  
pp. 72
Author(s):  
James Last Keyombe ◽  
◽  
Kevin Obiero ◽  
Edna Waithaka ◽  
Nicholas Outa ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Fish Species ◽  
Condition Factor ◽  
Micropterus Salmoides ◽  
Good Condition ◽  
Lake Naivasha ◽  
Early Maturity ◽  
Weight Relationship ◽  
Fish Samples ◽  
First Maturity

Coptodon zilli and Micropterus salmoides were introduced into Lake Naivasha in 1929 and 1959 respectively. The reasons for the introduction were to boost the fisheries and for recreational fishing respectively. However, the numbers of the two fish species in the lake have been declining over the years. It is therefore necessary to assess various aspects of their growth such as length-weight relationship, condition factor, sex ratio and length at first maturity to inform management and policy making for enhanced recovery and establishment of their populations. Length-weight relationship, condition factor, sex ratio and length at first maturity of the fish were studied from October 2016 to November 2018. A total of 303 fish samples; 193 C. zilli and 110 M. salmoides were studied. Results showed that C. zilli and M. salmoides had an allometry coefficient value of 2.9 and 3.1 and condition factor (K) value of 1.77 and 1.39 respectively. The sex ratios (male: female) of C. zilli and M. salmoides were 1.1:1 and 1.3: 1 respectively. The shortest total length for mature C. zilli and M. salmoides recorded were 12 cm and 26.5 cm while 21.8 cm and 51 cm were for the longest respectively. The fish growth pattern therefore failed to obey the cube law of b=3 thus exhibiting allometric growth. The two fish species were found to be in good condition with K factor above 1. It can therefore be concluded that the fish are generally in a good condition though the early maturity especially for C. zilli could be a sign of pressure either from environmental factors or human induced. Domination of the species by males, although a common feature in African lakes, is a case for concern since it presents uncertainty on the future of the fisheries. Restocking of Lake Naivasha with the two fish species should be considered and proper fishing practices enforced

scholarly journals Aspects of the Population biology of Common Carp, Cyprinus carpio (Linnaeus, 1758) In Lake Naivasha, Kenya

2020 ◽  
Author(s):  
Eunice Mutethya ◽  
Edwine Yongo ◽  
Cishahayo Laurent ◽  
Edna Waithaka ◽  
Evans Lomodei
Keyword(s):  
Common Carp ◽  
Cyprinus Carpio ◽  
Condition Factor ◽  
Lake Naivasha ◽  
Common Carp Cyprinus Carpio ◽  
Significant Difference ◽  
Fish Samples ◽  
Carp Cyprinus Carpio ◽  
The Mean ◽  
First Maturity

The Common carp, Cyprinus carpio is an exotic fish in Lake Naivasha. It is one of the commercially important species in the lake. This study investigated on its biology and population parameters during 2017. Fish samples (433) were caught using gillnets of mesh-sizes 2-5 inches. Length of fish ranged from 12.0 to 69.0 cm TL, and weighed between 32 and 6840 g. The overall population sex ratio was 1.66: 1.0 (male: female). The mean length of females was 34.8 cm and males 32.1 cm. The length at first maturity was calculated at 54.0 and 49.0 cm for females and males, respectively. The mean condition factor for all fish was 1.05. The peak condition values were recorded during April (1.35), September (1.59) and October (1.80). There was a significant difference in mean condition factor within the size classes highest (1.38) and lowest (0.93) values recorded in class 56-60 and 26-30, respectively. The overall asymptotic length (L∞) was 73.5 cm and growth curvature (K) 1.05 yr-1 with growth performance index (Ф) of 3.72. The total (Z), natural (M), fishing (F) mortality coefficients 2.85, 1.34 and 1.78 yr-1, respectively. The exploitation rate (E) of 0.57 was higher than optimum sustainable yield (E0.5) of 0.32, but not different from maximum sustainable yields (Emax) 0.54 and economic yield (E0.1) 0.46. The length at first capture (LC50) was lower than length at first maturity (LM50), suggesting capture of immature fish. This study provides parameters of fish biology and population often useful in fisheries management.

scholarly journals Some Aspects of Biology of Chola Punti Puntius Chola (Hamilton) from the Kangsa River

1970 ◽  
Vol 45 (4) ◽  
pp. 309-314
Author(s):  
Bi K Saha ◽  
A Saha
Keyword(s):  
Sex Ratio ◽  
Standard Length ◽  
Condition Factor ◽  
Fork Length ◽  
Head Length ◽  
Mean Values ◽  
Snout Length ◽  
Total Length ◽  
Relative Condition Factor ◽  
The Mean

The mean values of total length (75.89 ± 13.09 mm), standard length (54.98 ± 7.07 mm), fork length (60.86 ± 9.14 mm), head length (14.75 ± 2.05 mm), snout length (3.79 ± 0.61 mm), pre-dorsal length (31.53 ± 3.18 mm), height of body (20.2 ± 4.11 mm) and total weight (6.62 ± 3.55g) of combined sex of Puntius chola were calculated. Relationships between total length and standard length, fork length, head length, snout length and pre-dorsal length of Puntius chola were found to be linear, positive and highly significant. The length-weight relationship in male, female and combined sex were determined as Log W=-4.510+2.810 Log L, LogW=-4.204+2.685 Log L and Log W=4.465+2.808 Log L respectively. The mean values of condition factor from observed value (ko) of male, female and combined sex were determined as 1.36 ± 0.089, 1.599 ± 0.181 and 1.515 ± 0.192 respectively. The mean values of condition factor from calculated value (kc) of male, female and combined sex were found to be 1.362 ± 0.054, 1.6 ± 0.124 and 1.511 ± 0.075 respectively. The mean values of relative condition factor of male, female and combined sex were registered as 0.999 ± 0.044 , 0.999 ± 0.064 and 0.999 ± 0.112 respectively. Sex ratio was found to be 1:1. Key words: Standard length; Pre-dorsal length; Puntius chola; Morphomertric; Fish culture. DOI: 10.3329/bjsir.v45i4.7327 Bangladesh J. Sci. Ind. Res. 45(4), 309-314, 2010

scholarly journals Some Biological Aspects of Al - Shabbot Arabibarbus grypus (Heckel, 1843) in Al-Diwanyia River, Middle of Iraq

2019 ◽  
Vol 27 (2) ◽  
pp. 306-316
Author(s):  
Mohanad O. Abdullah Al-Jubouri ◽  
Abdul-Razak M. Mohamed
Keyword(s):  
Sex Ratio ◽  
Condition Factor ◽  
Age Groups ◽  
Allometric Growth ◽  
Relative Condition Factor ◽  
Fish Catch ◽  
Total Fish ◽  
Biological Aspects ◽  
The Mean ◽  
Somatic Index

      Some biological characteristics of shabbot, Arabibarbus grypus (Heckel, 1843) in the Al-Diwaniya River, middle of Iraq were studied from October 2016 to September 2017. Water temperature ranged from 10.2oC in March to 32.8oC in August. A total of 853 fish were caught by seine, gill and cast nets and electro-fishing. A. grypus constituted about 6.27% of the total fish catch. The length-weight relationship was W=0.021*L2.7548 revealing an allometric growth. The mean relative condition factor was 0.91. Five age groups wore recorded and their mean total lengths were 20.2, 32.0, 39.0, 43.9 and 48.4 cm, respectively. The growth model of the species was  Lt= 58 [1-e -0.39 (t-0.313)]. The growth performance index (Φ) of A. grypus was computed as 3.11. The study declares that the species is a omnivore, feeding mainly on aquatic plants, insects, algae and detritus. The overall sex ratio (female: male) was 1.47:1. The highest values of gonado- somatic index (GSI) were 4.20 for female and 1.78 for males in April. The fecundity of the species ranged from 75600 to 124200 eggs. 

scholarly journals Mudskipper, periophthalmodon schlosseri (pallas) from the Naf river

2013 ◽  
Vol 47 (4) ◽  
pp. 449-452 ◽  
Author(s):  
BK Saha
Keyword(s):  
Sex Ratio ◽  
Standard Length ◽  
Head Length ◽  
Caudal Peduncle ◽  
Snout Length ◽  
Weight Relationship ◽  
Total Length ◽  
Periophthalmodon Schlosseri ◽  
The Mean

A study on morphometrics, meristics sex ratio, ovary condition of Periophthalmodon schlosseri was conducted in 2001. The mean of total length (49.63 + 5.99 mm), standard length (40.84 + 5.30 mm), snout length (4.12 + 0.65 mm), head length (9.86 + 1.39 mm), height of body (6.89+1.24 mm) and the length of caudal peduncle (6.96 + 1.08 mm) were calculated. The length-weight relationship was determined as TW = 0.00004639+2.5882 TL. The fin formula was D1 . 8-9; D2 .1/10-13; P1 . 11-14; P2 . 11-14; A. 1/11. The sex ratio was found to be 1:0.63. The average of ovary length (6.2 +0.84 mm), ovary breadth (3.54 +0.95 mm) and diameter of ova (0.22 +0.04 mm) were also determined. Bangladesh J. Sci. Ind. Res. 47(4), 449-452, 2012 DOI: http://dx.doi.org/10.3329/bjsir.v47i4.14076

scholarly journals Population Aspects of Fishes in Geba and Sor Rivers, White Nile System in Ethiopia, East Africa

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Simagegnew Melaku ◽  
Abebe Getahun ◽  
Mulugeta Wakjira
Keyword(s):  
Sex Ratio ◽  
Fish Species ◽  
Condition Factor ◽  
Diversity Index ◽  
Abundant Species ◽  
Fish Diversity ◽  
Reproductive Behaviors ◽  
Fish Samples ◽  
The Mean ◽  
White Nile

This study was carried out to assess the diversity, condition factor, length-weight relationship, and sex ratio of fishes in Geba and Sor Rivers located in Baro-Akobo Basin, White Nile system within Ethiopia. Fish samples were collected in one wet and one dry season. The length-weight relationships were fitted using power equation for the most abundant species. A total of 348 fish specimens were collected using gillnets and hooks. These were identified into eight species and one Garra sp. representing seven genera and four families. Family Cyprinidae was the most dominant with six species (66.7%). Labeobarbus intermedius, Labeobarbus nedgia, and Labeo cylindricus were the most abundant fish species, respectively, with 60.72%, 16.83%, and 14.66% index of relative importance (IRI). The diversity index was higher for Geba River (H′ = 1.50) than for Sor River (H′ = 1.10). All the three most abundant species had negative allometric growth. Seasonal variations in the mean Fulton condition factor (FCF) were statistically significant for L. cylindricus (p<0.05). There was variation in the sex ratio with the females dominating in all the three most abundant species. Further investigation into the fish diversity, food, feeding, and reproductive behaviors of fish species especially in the tributaries of these rivers and their socioeconomic aspects is recommended.

scholarly journals Biologie De La Reproduction Du Sciaenidae Pseudotolithus Elongatus Dans La Lagune Ebrie (Cote d’Ivoire)

2016 ◽  
Vol 12 (6) ◽  
pp. 327
Author(s):  
Koné Tiéhoua ◽  
Kouakou Fokouo Kessia Irène ◽  
Konan Kouassi Sylvain ◽  
N’Da Konan
Keyword(s):  
Sex Ratio ◽  
Condition Factor ◽  
Size Class ◽  
Breeding Period ◽  
Total Length ◽  
Mean Diameter ◽  
Liver Somatic Index ◽  
The Mean ◽  
First Maturity ◽  
Somatic Index

The study of reproduction of Pseudotolithus elongatus in the Ebrie lagoon was investigated between July 2013 and June 2015 on a whole of individuals of 550 specimens. the total length ranges from 14.5 to 42.7 cm. The monthly evolution of the gonado-somatic index (GSI), the liver-somatic index (LSI), the condition factor (K), the Sex-ratio, the fecundity, the diameter of eggs revealed that this species spawns throughout the year but the main breeding period was in raining season. Sex-ratio observed was in favour of females (1: 1. 14; X2 = 2.26; p > 0.05). The percentage of mature specimens by sexes was calculated for each size class. Total length at first maturity was 21.06 cm for females and 20.21cm for males. The ripe ovaries contained 39883-814757 eggs. The relative fecundity was 216-1979 eggs per g of body weight of females. And the mean diameter of eggs is 336 ±138 microns.

scholarly journals LENGTH-WEIGHT RELATIONSHIP AND CONDITION FACTOR OF AFRICAN SNAKEHEAD PARACHANNA AFRICANA (STEINDACHNER, 1879) FROM IJEDE AND AGBOWA LAGOONS, LAGOS STATE, NIGERIA

2020 ◽  
Vol 9 ◽  
pp. 35
Author(s):  
Mistura Temitope Adeleke ◽  
Oladunni Nimota Adekunle ◽  
Olusegun Adebayo Lawal ◽  
Fayokunfe Mayowa Adeyemi
Keyword(s):  
Condition Factor ◽  
Well Being ◽  
Growth Patterns ◽  
Allometric Growth ◽  
B Values ◽  
Practical Applications ◽  
Weight Relationship ◽  
Fish Samples ◽  
Lagos State ◽  
The Mean

The knowledge of length-weight relationship parameters has numerous practical applications in fishery research and management. Currently, there is a dearth of information on the growth pattern and state of well-being of Parachanna africana in Ijede and Agbowa Lagoons. This study period was between December 2017, and June 2018 investigated the allometry and condition factor of P. africana inhabiting the Ijede and Agbowa Lagoons, South-western Nigeria. Two hundred fish samples of P. africana was gotten from fishermen at both locations. The length and weight measurements were taken to the nearest centimetres and grams. Descriptive, correlation and regression tools, was used to 2analyse the data collected. Results obtained showed that the length-weight relationship had r values of  0.186, 0.196, 0.191 and 0.341, 0.001, 0.098 for Ijede and Agbowa respectively, at a significant level of  P<0.05 for male, female and combined sexes. The b values of 0.193 for Ijede and 0.165 for Agbowa were not significantly different (P> 0.05). The mean condition factors of 0.365 ±0.141 and 0.329±0.169 were obtained in Ijede and Agbowa, respectively. It was observed that the species in both lagoons exhibited negative allometric growth patterns with values 0.365 and 0.330 for Ijede and Agbowa lagoons respectively with no variations in the condition factors of both locations which indicate the need to assess human and domestic activities surrounding these water bodies.

scholarly journals Study of some biological aspects of the Nile Carp, Labeo niloticus (Pisces, Cyprinidae) from Khashm El-Girba Reservoir and Atbara River; Eastern Sudan: II, length-weight relationship, condition factor and age structure

2021 ◽  
Vol 3 (2) ◽  
pp. 7-14
Author(s):  
Mutasim Yousif Mohamed Abdalla ◽  
◽  
Abuelgasim Ibrahim Abdelhalim ◽  
Ahmed El Bedawi Adam ◽  
◽  
...  
Keyword(s):  
Age Structure ◽  
Growth Pattern ◽  
Condition Factor ◽  
Allometric Growth ◽  
Beach Seine ◽  
Weight Relationship ◽  
Biological Aspects ◽  
The Mean ◽  
The Relationship ◽  
Eastern Sudan

This study was undertaken to assess the length-weight relationship, condition factor and age structure, of the Nile carp, Labeo niloticus, in Khashm El-Girba reservoir and Atbara River, Sudan, from December 2015 to November 2016. Samples of fish were collected bi-monthly from three locations, namely; Um Aswad (Atbara River), El-Remila and El-Monaba (Khashm El-Girba reservoir), using beach seine nets of 1.2, 4.0 and 7.0 cm stretched mesh. Out of a total number of 1,190 specimens of L. niloticus collected from the three sampling sites, 189 specimens were randomly selected to determine age. The relationship between length and weight indicated negative allometric growth pattern in all three locations, where the slope (b) of the (LWR) was highly significant (p<0.001) and ranged from 2.178 to 2.885. The mean condition factor (K) varied monthly in the three locations with values ranging from 1.671 in Um Aswad (Atbara River) to 2.548 in El-Monaba (reservoir). Although the age of L. niloticus ranged from 0+ and 3+ years, yet, most of the studied fish are between age 0 + and 1+.

Sign in / Sign up

Export Citation Format

Share Document