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1.
Length–weight and length–length relationships were estimated for 10 freshwater, estuarine and marine fish species caught at the mouths of coastal sterams from northwestern Baja California (Mexico). The parameter b estimated by nonlinear least squares of weight and length data, ranged from 2.50 to 3.61. Size conversions (calculated total length from standard length) can be used in fishery for understanding several aspects of population dynamics.  相似文献   

2.
The length–weight relationship parameters were recorded for 24 families, 34 genera and 46 species of 10 963 specimens sampled off the western coast of Baja California Sur, Mexico, many for the first time. New maximum length records were obtained for seven of these species. The b values ranged from 2.62 for Sebastes rubrivinctus to 3.80 for Peprilus simillimus .  相似文献   

3.
This study describes the length–weight (LWR) and length–length (LLR) relationships for ten small indigenous fish species from the lower part of the Ganges, Bangladesh, namely Ailia coila , Amblypharyngodon mola , Aspidoparia morar , Clupisoma atherinoides , Eutropiichthyes vacha , Glossogobius giuris , Gudusia chapra , Lepidocephalus guntea , Mystus vittatus , and Puntius ticto . A total of 2142 specimens, representing 10 species of 5 families used for this study were caught by traditional fishing gear from March 2006 to February 2007. Standard length (SL), total length (TL) and fork length (FL) for each specimen were measured by digital slide calipers and each body weight (BW) was taken by a digital balance. The allometric coefficient b of the LWR was close to the isometric value ( b  =   3.001) in G. giuris , although it suggested negative allometric growth in A. coila, A. morar, C. atherinoides, E. vacha, and P. ticto, whilst positive allometric growth in rest of the species. The results further indicated that the LLRs were highly correlated ( r >   0.890; P < 0.01). To the best our knowledge, this study presented the first reference on LWR and LLR for most of the species in Bangladesh.  相似文献   

4.
Ninety-nine length–weight relationships (LWR) were estimated for 70 bentho-demersal fish species captured in four Brazilian estuaries between latitudes 0°S and 25°S. LWR are published for the first time for 13 species. The allometry coefficient ( b ) of the LWR ( W = aTL b ) showed a median of 3.147. Positive allometry was dominant (64 of the 99 species x estuary cases), followed by isometry (28) and negative allometry (7). Twenty-two species were caught in two or more estuaries. In most cases (29 of 33 comparisons), the values of both regression parameters differed significantly among estuaries.  相似文献   

5.
We present the relationships between total (TL), fork (FL) and standard (SL) length for 37 fish species and the relationships between TL and wet weight for 40 fish species from the Aegean Sea (Cyclades; Greece). The relationships between TL, FL and SL were all linear (for all cases: r 2 > 0.928). The values of the exponent b of the length–weight relationships ranged from 2.235 to 3.704.  相似文献   

6.
The relationships between total (TL) and standard (SL) lengths for 50 fish species and between TL and wet weight for 52 fish species caught in the Ouémé River are presented. Relationships between TL and SL are linear. Between TL and weight, the relationships are of the form TW = aTLb. The b values range from 2.3307 to 3.5185. Student's t‐test revealed that 38.5% of the species have b values significantly different from 3.  相似文献   

7.
Length–weight and length–length relationships are described for 10 of the most important and most frequent small, middle‐size and large pelagic fish species from the Adriatic Sea, namely Sardina pilchardus Walbaum 1792, Sardinella aurita Valenciennes 1847, Sprattus sprattus Linnaeus 1758, Engraulis encrasicolus Linnaeus 1758, Belone belone Linnaeus 1761, Scomber scombrus Linnaeus 1758, Scomber japonicus Houttuyn 1780, Thunnus thynnus Linnaeus 1758, Auxis rochei Risso 1810 and Sarda sarda Bloch 1793. Length–length equations for converting size measurements: standard length (SL) and fork length (FL) to total length (TL) and vice versa, were linear.  相似文献   

8.
9.
The present study describes the length–weight (LWR) and length–length (LLR) relationships for eight important small indigenous fish species (SIS) from the Mathabhanga River, southwestern Bangladesh, namely Amblypharyngodon mola (Hamilton, 1822), Channa punctata (Bloch, 1793), Hyporamphus quoi (Valenciennes, 1847), Macrognathus aculeatus (Bloch, 1786), M. pancalus (Hamilton, 1822), Nandus nandus (Hamilton, 1822), Puntius sophore (Hamilton, 1822), and Setipinna phasa (Hamilton, 1822). A total of 2543 specimens used for this study was caught by traditional fishing gear from January to December 2005. To the best knowledge of the authors, this study presented the first reference on LWR and LLR for these species from Bangladeshi waters.  相似文献   

10.
The seasonal and interannual proximate and sterol composition were assessed in two red (Gelidium robustum, Gelidiaceae and Gracilariopsis sjoestedtii, Gracilariaceae), two brown (Ecklonia arborea, Lessoniaceae and Macrocystis pyrifera, Laminariaceae), and two green (Ulva lactuca and Ulva clathrata, Ulvaceae) macroalgae species and the seagrass Phyllospadix torreyi (Zosteraceae) sampled over 3 years in a subtropical climate in Baja California Sur, Mexico. Each macroalga had a particular sterol composition that was typical of their taxonomic group. The red algae had cholesterol as the major sterol; 92% on average in G. robustum and 90% in G. sjoestedtii, followed by t‐dehydrosterol and brassicasterol. In the brown algae the major sterol was fucosterol, which accounted for approx. 90% and 92% of total sterols for M. pyrifera and E. arborea, respectively, followed by campesterol (7% and 5%) and isofucosterol (1.5% and 1.3%). The green algae had isofucosterol as the major sterol, with 92% on average for U. lactuca and 87% for U. clathrata, followed by cholesterol, fucosterol, and brassicasterol or norcholesterol. The seagrass P. torreyi had β‐sitosterol as the major sterol (39 to 89%, depending on the season), followed by campesterol (4 to 7%), stigmasterol (3 to 6%), and isofucosterol (1.7 to 3.5%). Four (cholesterol, campesterol, fucosterol, and isofucosterol) of the 14 sterols identified in macroalgae and the seagrass could be used to differentiate between classes (Florideophyceae – red, Phaeophyceae – brown, Ulvophyceae – green, and Monocots – seagrass) both seasonally and interannually. The seasonal and interannual sterol composition of macroalgae and seagrass was quite stable, with the exception of red G. sjoestedtii sampled in August and green macroalga U. lactuca and seagrass P. torreyi both sampled in May 2002. Seasonal and interannual variations of proximate and sterol composition are discussed in relation to their reproductive state and environmental parameters.  相似文献   

11.
Length–weight relationships of 33 cryptic reef fishes from the southwestern Gulf of California were estimated. The most common families were Gobiidae (seven species), Labrisomidae (four), Pomacentridae (three), and Tripterygiidae (three). These are the first length–weight parameters reported for 32 of these species. Specimens were sampled during a comparative ecological study of community structure of fish assemblages associated with coral heads, rocky walls, and artificial reefs in Bahía de La Paz, Baja California Sur. The b values varied between 2.63 and 3.61. New maximum length records for five of the species were established in the study.  相似文献   

12.
13.
Length–weight relationships were estimated for 24 freshwater fish species of Iran. Significant length–weight relationships with high correlation coefficient were found for all species. The value of the parameter b varied between 2.881 and 3.545.  相似文献   

14.
Studies on coccolithophorids in Mexico are rather scarce, probably due to the use of traditional methods for studying marine phytoplankton (e.g. collection, preservation and analysis). This is the first study of the coccolithophorid flora from west coast of Baja California, Mexico. Bottle samples (4 l) were taken at various depths (5, 25 and 50 m), at fixed stations located on perpendicular transects along the west coast of Baja California, considering three different zones: North, Central and South. A total of 32 samples were studied by optical and scanning electron microscopy, yielding 24 taxa identified (17 species and 5 nominal varieties, plus 2 different varieties). The coccolithophorid assemblages are considered subtropical and coastal (with many cosmopolitan taxa). Emiliania huxleyi and Gephyrocapsa oceanica were the most abundant (relative abundance) and widespread species in the study area. We report 15 new records for the Mexican Pacific. The zonal and vertical distribution of some taxa are briefly discussed, as well as the taxonomy of Rhabdosphaera claviger, Helicosphaera carteri, H. hyalina and related taxa.  相似文献   

15.
Length–weight relationships are presented for some 83 fish species representing 31 families captured in South African estuaries.  相似文献   

16.
17.
Length–weight relationships (LWR) were estimated for Acanthobrama mirabilis, Barbus pectoralis, Chondrostoma meandrense, Capoeta bergamae, Silurus glanis, Petroleuciscus smyrnaeus and Cyprinus carpio from the Kemer reservoir in western Anatolia, Turkey. This study is the first reference on length–weight parameters for five of these species.  相似文献   

18.
Length–weight relationships are lacking for most deep-sea fishes. This study presents length–weight relationships for 42 species from the western Bering Sea. Results show significantly different relationships between females and males for 11 species and between juveniles and adults of four species. A plot of length–weight estimates, log a over b , showed the deep-sea fishes in this study to be more of the elongated shape compared with other marine fishes.  相似文献   

19.
20.
Length–weight and length–length relationships are presented for three species of butterflyfish endemic to the Hawaiian Islands and Johnston Atoll. From specimens collected within the Papahānaumokuākea Marine National Monument (PMNM), the weight–length relationships were determined for Chaetodon fremblii as W  = 0.029SL3.17, Chaetodon miliaris as W  = 0.042 SL3.00, and Chaetodon multicinctus as W  = 0.029SL3.19 where weight, W , is reported in grams and standard length, SL, in centimeters. Length-frequency data and equations to calculate total length from standard length are also presented.  相似文献   

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