Standard Weight (W_s) Equations for Four Rare Desert Fishes

Abstract

Standard weight (Ws) equations have been used extensively to examine body condition in sport fishes. However, development of these equations for nongame fishes has only recently been emphasized. We used the regression‐line‐percentile technique to develop standard weight equations for four rare desert fishes: flannelmouth sucker Catostomus latipinnis, razorback sucker Xyrauchen texanus, roundtail chub Gila robusta, and humpback chub G. cypha. The Ws equation for flannelmouth suckers of 100–690 mm total length (TL) was developed from 17 populations: log10 Ws = −5.180 + 3.068 log10TL. The Ws equation for razorback suckers of 110–885 mm TL was developed from 12 populations: log10 Ws = −4.886 + 2.985 log10TL. The Ws equation for roundtail chub of 100–525 mm TL was developed from 20 populations: log10 Ws = −5.065 + 3.015 log10TL. The Ws equation for humpback chub of 120– 495 mm TL was developed from 9 populations: log10 Ws = −5.278 + 3.096 log10TL. These equations meet criteria for acceptable standard weight indexes and can be used to calculate relative weight, an index of body condition.

Parameters associated with growth factors of five fish species in the Atrai River, Dinajpur, Bangladesh

“…Condition factors (CFs) are commonly used to know the health status, physiology, reproduction and survival (Didenko et al 2004;Richter, 2007) and to compare relative health of fishes (Froese, 2006). Fulton's condition factor (CF f ), free from regression parameters (a & b), exploited to know the physical status of fishes.…”

Estimating Geographic Variation in Allometric Growth and Body Condition of Blue Suckers with Quantile Regression

“…Recently, there has been increased use of W r for quantifying body condition of non-sport fishes (Bister et al 2000;Didenko et al 2004;Richter 2007;Rypel and Richter 2008;Ogle and Winfield 2009), such as the blue sucker. If body condition indices (e.g., W r ) of fish are to be used to characterize and interpret changes in the health of fish populations and associated aquatic systems, then knowledge about how best to estimate temporal and spatial variation in body condition indices is essential (Murphy et al 1991;Porath et al 2003;Pope and Kruse 2007).…”

Length–weight and length–length relationships for three endemic cyprinidspecies of the Aegean region (Turkey) with proposed standard weight equations

“…the presence of nonnative species) (Giannetto et al, 2012b). The use of condition indices such as relative weight to evaluate the status of threatened rare or less-studied species is indeed strongly recommended (Didenko et al, 2004), since they are not invasive methods and do not require the sacrifice of the specimens (Fechhelm et al, 1995).…”