“…This correction (henceforth depth corrected TL) can be interpreted as having adjusted the ALPP to be the same as if the foreground fiducial marker was positioned at the distal plane. To calculate depth corrected TL, the width of the fish is required, which can be estimated from the length, provided the length-width relationship is known (Jeong, Yang, Lee, Kang, & Lee, 2013;Loy, Boglione, Gagliardi, Ferrucci, & Cataudella, 2000;Rohlf & Marcus, 1993;Tulli, Balenovic, Messina, & Tibaldi, 2009). However, depth corrected TL is subject to systematic error because the estimated length used to derive width is itself an underestimate.…”