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1.
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   

2.
The study reports length–weight relationships for 36 species belonging to 20 families of the estuarine zone of the Sinú River in northern Colombia. To the best knowledge of the authors, this study presents the first study on length–weight relationships for 10 species worldwide as well as seven new maximum lengths.  相似文献   

3.
Length–weight relationships were estimated for 56 species, representing seven orders and 17 families of fishes from the Upper Uruguay River, Brazil. For most of these species, no length–weight relationships were previously available.  相似文献   

4.
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   

5.
Length–weight relationships were estimated for 20 species of the Jurumirim reservoir (southern Brazil): one Pimelodidae, one Callichthyidae, six Characidae, one Prochilodontidae, six Anastomidae, one Erythrinidae, two Curimatidae, one Paradontidae and one Cichlidae. The fishes were collected during 2001–2002 using three different types of fishing gear that allowed collection of both adult and juvenile specimens. The first reference of length–weight relationships for 12 species is provided.  相似文献   

6.
This study reports length–weight relationships for Apareiodon affinis , Leporinus obtusidens , Cynopotamus argenteus , Loricariichthys melanocheilus , Parapimelodus valenciennis , Iheringichthys labrosus , Rhinodoras dorbignyi and Pachyurus bonariensis . Specimens were collected between 2006 and 2007 from the lower section of the Uruguay River. The study represents the first reference on weight–length relationships for three species and also provides the new maximum size for three species.  相似文献   

7.
Presented are the length–weight relationships of 12 fish species [ Oncorhynchus mykiss (Walbaum, 1792); Cyprinus carpio, Linnaeus, 1758; Carassius carassius Linnaeus, 1758; Alburnoides bipunctatus (Bloch, 1782); Alburnus adanensis Battalgazi, 1944; Rutilus rutilus , Linnaeus, 1758; Squalis cephalus, Linnaeus, 1758; Tinca tinca (Linnaeus, 1758); Capoeta barroisi (Valenciennes, 1842); Silurus glanis Linnaeus, 1758; Gambussia affinis (Baird and Girard, 1853); and Sander lucioperca (Linnaeus, 1758)] from Seyhan Dam Lake, Turkey. This study provides the first estimation of length–weight relationships for two of the species ( A.   adanensis and C. barroisi ).  相似文献   

8.
This study provides new length–weight relationship information for 21 neotropical fish species. Specimens were collected between 2004 and 2005 from the lower section of the Santa Lucía river basin (Uruguay). Presented are also the first reference on weight–length relationships for these 21 species, and new maximum sizes for six of these species.  相似文献   

9.
This paper presents 43 length–weight relationships of coastal fish species of the families Carangidae, Lutjanidae and Haemulidae from the central Mexican Pacific. New maximum length values for 15 fish sepcies are included.  相似文献   

10.
1. The relationships between body length and dry weight were examined for eight species of freshwater planktonic crustacea common in Japan: Eodiaptomus japonicus, Acanthodiaptomus pacificus, Daphnia galeata, D. similis, D. magna, Scapholeberis mucronata, Simocephalus exspinosus and Bosmina longirostris.
2. The relationships of two diaptomid species were similar and the approximate equation was ln W = 2.7 + 2.6*ln L , where L is prosome length (mm) and W is dry weight (μg). The carapace length–dry weight relationships in branchiopods were more variable, with the slope ranging from 1.9 to 2.9 and the intercept from 2.0 to 3.7.
3. The effects of food conditions on the relationship were examined in the laboratory, and the seasonal changes in the field were also studied.
4. Practical advice is presented for predicting crustacean weight from body length.  相似文献   

11.
This study describes the length–weight relationship (LWR) of the clown knifefish, Chitala chitala, in the River Ganga basin, India. A total of 221 specimens ranging from 31 to 120 cm total length (TL) and 550 to 12 000 g total weight (TW) were collected. Chitala chitala constitutes an important component of riverine fisheries of India and is considered one of the most commercially important and highly priced foods in addition to being an aquarium fish. The species has recently undergone heavy fishing pressure, leading to an alarming decline in natural populations and deserving of high conservation importance. Length–weight relationships of C. chitala from wild populations had not yet been studied. Hence, the study objective was to evaluate length–weight relations of C. chitala from eleven populations in order to help in conservation and management of the riverine population.  相似文献   

12.
The length–weight relationship parameters and seasonal reproductive cycle are recorded for six commercially important fish species caught in the coastal lagoon of Tres Palos. The length–weight information is new to the literature for three of these species (spot cichlid, spotted sleeper, Pacific fat sleeper) and is within the expected range for the other three (widehead sea catfish, three spot cichlid, white mullet). Differences between sexes are statistically significant for four species and deviations from isometric growth are indicated in three species. The reproductive period for the Pacific fat sleeper differed substantially from the period reported for this species in Ecuadorian waters.  相似文献   

13.
This study reports length–weight relationships for 17 cryptic and rare species, Aidablennius sphynx , Arnoglossus kessleri , Callionymus pusillus , Callionymus risso , Clinitrachus argentatus , Echiichthys vipera , Gobius geniporus , Gobius paganellus , Labrus viridis , Lepadogaster lepadogaster , Ophidion barbatum , Pomatoschistus minutus , Pomatoschistus pictus , Salaria pavo , Tripterygion delaisi , Tripterygion tripteronotus and Zebrus zebrus from Çanakkale near shores in the Marmara region of Turkey.  相似文献   

14.
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   

15.
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   

16.
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   

17.
Samples of 525 Scorpaena porcus (Linnaeus, 1758) were collected from the southeastern Black Sea between January 2002 and May 2003 for information on age, growth, length–weight relationships and stomach contents. Total length of sampled fish ranged from 4.6 to 22.9 cm and total weight from 1.3 to 220 g. The sex ratio (1 : 1.61) was biased toward females (P < 0.05). Positive allometric growth was determined in the collected samples. The length–weight relationship for all individuals was described by the parameters a  = 0.0149 and b  = 3.09, with r 2 = 0.99. The sample was composed of five age-classes (0–7 years). Three growth models were used to identify the growth characteristics: von Bertalanffy,     ; logistic,     ; and Schnute and Richards,     . Among these, the Schnute and Richards model was best fitted to the data as     The diet was composed of Carcinus mediterraneus (18.2%), Crangon crangon (12.1%), unidentified crab species (10.6%), Gobius sp. (4.6%), Palaemon sp. (4.5%), Macropipus sp. (4.5%), Engraulis encrasicholus (1.5%), Gastropoda (1.5%), and unidentified remains (34.9%).  相似文献   

18.
The Japanese silver-biddy Gerres equulus (Temminck and Schlegel) is one of the most common shore fishes in the costal waters of southern Japan and commercially important for the local fishery. In this study the condition factor, length–weight (LWR) and length–length relationships (LLR) of G. equulus are described for the first time. A total of 1121 specimens (511 males; 620 females) were collected using gill nets in the Yatsushiro Sea, western Kyushu, Japan. The overall allometric coefficient b of LWR was close to the isometric values ( b  =   3.088). Fulton's condition factor showed high values at the beginning of the spawning season (June–September) and peaking 2 months after the spawning season.  相似文献   

19.
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   

20.
1. Cross-species macroecological comparisons in freshwater invertebrates have been restricted by a lack of large-scale distributional data, and robust phylogenies. Here, we use data from the OdonataCentral database to explore body length–range size and wing length–range size relationships in damselflies from the genus Enallagma ; the recent publication of a phylogeny for this group meant that, as well as a cross-species analysis, we were able to assess relationships in a phylogenetically controlled manner.
2. For cross-species comparisons, only wing length showed significant (positive) regression relationships with range size and occupancy, although the inclusion of body length in multiple regressions increased the fit of the models. Damselflies with larger wings relative to their body length had larger distributions, a result confirmed by a significant positive relationship between range size and residuals from the regression of wing size on body size.
3. For the phylogenetically controlled analyses, only wing length contrast scores were significantly related to distribution patterns and entered into regression models; the significant positive relationships between wing length contrasts and both range size and occupancy contrasts suggested that evolutionary increases in wing length had occurred alongside range expansions.
4. Together these results suggest that species of Enallagma with larger wings (both absolute and relative to body length) tend to be more widely distributed in North America and that the evolution of wing size may have played a role in range expansion. No such relationships were evident for body size. We discuss the potential importance of wing morphometrics for studying the evolutionary ecology of freshwater insects.  相似文献   

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