According to Schnute (1981), if [lambda] = 1, the model corresponds to the specialized VBGM.
The VBGM has been commonly used to describe the growth pattern in geoduck species such as Panopea abbreviata (Morsan & Ciocco 2004, Morsan et al.
This is the first use of the Gompertz growth model to describe the individual growth pattern of Panopea globosa, as an alternative to the traditional VBGM (Table 4).
The Schnute model is a general four-parameter growth model that contains most of the other growth models as special cases, including the common form of the VBGM, the logistic function, and the Gompertz model as special cases.
If only the VBGM results are considered, however (Table 3), the estimated asymptotic SL is within the range found for Panopea generosa in Washington state (132-173 mm [Hoffmann et al.
The VBGM is typically used simply because is the best known and most commonly applied length-at-age model, but its exclusive use is not well supported.
Table 1 shows the VBGM parameters estimated for Panopea generosa in Washington state (132-173 mm [Hoffmann et al.
We used the individual parameters of the VBGM by species (Table 1) to calculate the average length-at-age ([Lt.
Another item worth noting is the performance of the four growth curves obtained from the average VBGM.
It is unlikely that geoducks are larger than 30 mm at time t = 0; however, the growth curves generated by VBGM for each species are in the acceptable range.
globosa populations in the Gulf of California are the target of a rapidly growing fishery, and an understanding of population growth parameters is required to develop sustainable harvesting strategies, there is only 1 article that addresses this topic, and it was limited to the use of the VBGM (Cortez-Lucero et al.
Although the VBGM is the most studied and most commonly applied model among all length-at-age models, its use as the sole growth model is not well supported.