Length–weight relationships of some freshwater fishes of Iran

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.     

Length–weight relationships of fishes from South African estuaries

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

Length–weight relationships of deep-sea fishes from the western Bering Sea

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.     

Length–weight relationships for seven freshwater fishes caught in Kemer reservoir, Turkey

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.     

Abundance–body mass relationships among insects along a latitudinal gradient

Abstract We investigated the relationship between abundance and body size (body mass) of 162 insect herbivore species on the host plant Acacia falcata along its entire coastal latitudinal distribution (eastern Australia), spanning a gradient in mean annual temperature of 4.3°C. We extend previous research by assessing these relationships at different spatial scales (latitudes pooled, among latitudes and within latitudes) and at different taxonomic levels (insect phytophages pooled, phytophagous Coleoptera and Hemiptera, and five component suborders/superfamilies). Insect species were collected from two orders (Hemiptera and Coleoptera) and five component suborders/superfamilies. There were no consistent trends in the relationships (linear or polygonal/hump‐shaped) between abundance and body mass when latitudes were pooled, among latitudes, or when phytophagous insect species were separated into their component suborder/superfamily groups. The reason for the lack of consistent trends might be due to the insect herbivores not fully exploiting their host plant and the relative absence of competition among herbivore species for food resources. This is further assessed in relation to the lack of a consistent pattern in species richness of Coleoptera and Hemiptera herbivores from the same dataset and rates of chewing and sap‐sucking herbivory along the same latitudinal gradient. Future studies of abundance–body size relationships are discussed in relation to sampling across environmental gradients and accounting for the influence of host plant identity and insect phylogeny.     

Length–weight relationships for estuarine fishes in South Brazil

The present study reports the length‐weight relationships (LWRs) for 18 estuarine species sampled in Guaratuba Bay, South Brazil. For the majority of these 18 species the LWRs are known from the literature, but these estimates do not consider sexes separately which is done in this contribution. Different fishing gears were used in the samplings (cylindrical nets – 1 mm mesh size, bottom trawls – 250 mm mesh size in the arms and 12 mm mesh size in the bag, beach seine – 5 mm mesh size and hook and line fishery) between September 2007 to April 2014. The specimens were sexed and the LWRs were calculated for each sex separately. There were differences between sexes in growth type, showing the importance of sexing in these studies. We reported for the first time (based on FishBase) the LWRs for two species: Ctenogobius shufeldti and Hypleurochilus fissicornis.     

Length–weight relationships for fishes caught by shrimp trawl in southern Bahia, Brazil

Length–weight relationships (TW =  a TL ^b ) were estimated for fish species caught by bottom shrimp trawl in southern Bahia (Brazil) from March 2003 to February 2005. The results indicate that all 21 estimated relationships had a ' b ' within the usual range (2.5–3.5). Two new maximum size records were established: 19.2 cm for Odontognathus mucronatus and 16.1 cm for Stellifer brasiliensis .     

Length–weight relationships of fishes captured from Izmir Bay, Central Aegean Sea

Weight–length relationships are presented for 60 fish species captured from Izmir Bay, Central Aegean Sea. Samples were collected using bottom trawls (mesh sizes 24 mm at stretched cod‐end). The b values W = aL^b showed a mean value of 3.027 (SE = ±0.03) and more than 50% of the values ranged between 2.912 and 3.189. One species, Cepola macrophthalma, showed strong negative allometric growth.     

Length–weight relationships for selected fish species from three eastern Adriatic estuarine systems (Croatia)

Length–weight relationships are presented for fish species from three eastern Adriatic estuarine systems (Croatian waters). The values of the parameter b mostly remained within the expected range of 2.5–3.5. No information regarding the length–weight relationship previously existed for 11 of the species.     

Length–weight and length–length relationships for some continental fishes of northwestern Baja California, México

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.     

Length–weight relationships of cryptic reef fishes from the southwestern Gulf of California, Mèxico

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.     

Sex‐biased transcriptome divergence along a latitudinal gradient

Sex‐dependent gene expression is likely an important genomic mechanism that allows sex‐specific adaptation to environmental changes. Among Drosophila species, sex‐biased genes display remarkably consistent evolutionary patterns; male‐biased genes evolve faster than unbiased genes in both coding sequence and expression level, suggesting sex differences in selection through time. However, comparatively little is known of the evolutionary process shaping sex‐biased expression within species. Latitudinal clines offer an opportunity to examine how changes in key ecological parameters also influence sex‐specific selection and the evolution of sex‐biased gene expression. We assayed male and female gene expression in Drosophila serrata along a latitudinal gradient in eastern Australia spanning most of its endemic distribution. Analysis of 11 631 genes across eight populations revealed strong sex differences in the frequency, mode and strength of divergence. Divergence was far stronger in males than females and while latitudinal clines were evident in both sexes, male divergence was often population specific, suggesting responses to localized selection pressures that do not covary predictably with latitude. While divergence was enriched for male‐biased genes, there was no overrepresentation of X‐linked genes in males. By contrast, X‐linked divergence was elevated in females, especially for female‐biased genes. Many genes that diverged in D. serrata have homologs also showing latitudinal divergence in Drosophila simulans and Drosophila melanogaster on other continents, likely indicating parallel adaptation in these distantly related species. Our results suggest that sex differences in selection play an important role in shaping the evolution of gene expression over macro‐ and micro‐ecological spatial scales.     

Length–weight relationships of six freshwater fishes from small streams flowing into Lake Sapanca, NW Turkey

Length–weight relationships are given on six freshwater fish species ( Phoxinus phoxinus , Cobitis vardarensis , Neogobius gymnotrachelus , Proterorhinus marmoratus, Petroleuciscus borysthenicus and Gambusia holbrooki ) from four streams flowing into Lake Sapanca, north-western Turkey.     

Length–weight relationships for 31 teleost fishes caught by bottom trawl net in the Babadillimani Bight (northeastern Mediterranean)

Length–weight relationships (LWR) were estimated for 31 teleost fish species caught in the Babadillimani Bight on the western entrance of Mersin Bay, Turkey. Sampling was carried out from May 1999 to April 2000 at monthly intervals using bottom trawl nets of 6 mm cod‐end mesh size. The b values varied from 2.662 for Echelus myrus to 3.395 for Gobius niger, with a mean of 3.024 (±0.166). This study presents the first estimation of LWR for seven species (Blennius ocellaris, Centracanthus cirrus, E. myrus, Engraulis encrasicolus, G. niger, Synodus saurus, and Zeus faber) distributed along the northeastern Mediterranean coastal area.