Age, growth and length–weight relationship of Echiophis brunneus inthe Ecuadorian Pacific: A Bayesian multimodel approach
DOI:
https://doi.org/10.25268/bimc.invemar.2026.55.2.1363Keywords:
Age and growth, multimodel analysis, Bayesian statistics, sagittal otoliths, length– weight relationshipAbstract
The speckled worm eel (Echiophis brunneus) is an anguilliform fish species with a high incidence in artisanal catches in Ecuador. However, globally, many aspects of its biology remain unknown. This study aimed to estimate age and growth within the population structure of E. brunneus along the coast of Manabí, Ecuador. Between June and November 2024 specimens
were collected from artisanal fisheries. In the laboratory, sagittal otoliths were extracted to determine age and growth parameters through a multimodel analysis (von Bertalanffy, Logistic, Gompertz) using Bayesian statistics, given the absence of juveniles in the sample. A total of 110 females and 90 males were analysed, with total lengths ranging from 43 to 189 cm TL. The results indicated negative allometric growth, with estimated ages ranging from 1 to 9 years. The von Bertalanffy model provided the best fit according to the cross-validation criterion (LOOIC), yielding estimates of L∞ = 181.28 cm and k = 0.24 yr-¹. The growth pattern reflects a faster increase in length than in weight, indicating slow to moderate growth and a moderate asymptotic length. These findings provide a biological baseline that may be used in future fisheries assessments and population studies of the species.
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