Length–weight relationships of eight fish species from Guyana coastal drainages, Amapá, Brazil

Abstract

The present study provides the length–weight relationships (LWR) for eight fish species in 19 streams from the Pedreira River basin, a small tributary of the Guyana coastal drainages from Amapá State, Brazil. Fishes were collected at two occasions, one in November 2016, the other in July 2018, using hand nets, with 0.5 mm of mesh size and 0.25 m2 of mouth area, and trawl nets, with 0.5 mm of mesh size and 3 m long. Standard length and total weight were measured to determine the LWRs. The results show that the coefficient b varied between 2.798 and 3.380 and thus the values were within the expected range.

Length-weight relationship of four species of ornamental fish from the lower Rio Negro basin in the Brazilian Amazon

“…Although information on parameters a and b can be found on FishBase (www.fishbase.org), the values are based on Bayesian prediction and may not be exact. Notwithstanding, LWR estimates have already been published elsewhere for Pseudoloricaria laeviuscula (Giarrizzo et al, 2015;Hashiguti, Begot, Prudente, Freitas, & Montag, 2017), Nannostomus unifasciatus (Santos et al, 2012), Hemigrammus levis (Salvador et al, 2019;Sampaio, Santos, Anjos, Freitas, & Souza, 2019) and Acarichthys heckelii (Matos et al, 2019;Lubich et al, 2020). Giarrizzo et al (2015) presented the value of b= 3.26 for the species P. laeviuscula, which is similar to that found in this study (b =3.21).…”

“…H. levis is the only species whose available estimates (Salvador et al, 2019;Sampaio et al, 2019) are within the range of the Bayesian estimate, including that reported in the present study. Although the values of b reported by Salvador et al (2019) of b=3.17, andSampaio et al (2019) of b=3.20, are similar to each other and different to the value reported herein (b=2.52).…”

Length-weight relationships of ornamental fish from floodplain lakes in the Solimões River basin (Iranduba, Amazonas, Brazil)

“…Because of this diversity, studies about length-weight relationships (LWR) of ornamental fish have been more frequent, highlighting the studies by Santos et al (4), Gaspar et al (5), Barros et al (6), Freitas et al (7) and Salvador et al (8). Nevertheless, still there is a lack of information and few studies were conducted in the Solimões River basin about the LWR of ornamental fish species from floodplain lakes.…”