Ju P., Cheung W.W.L., Lu Z., Yang S., Guo Z., Chen M., Xiao J. 2019. Age, growth, and abundance fluctuation of Jordan’s damsel, Teixeirichthys jordani (Actinopterygii: Perciformes: Pomacentridae), in the southern Taiwan Strait. Acta Ichthyol. Piscat. 49 (3): 243–250.
Information on the age, growth, and abundance fluctuation is important for fisheries conservation and management because stock assessment models rely on these biological parameters. However, the limited biological information makes it difficult to develop the proper and effective management for Jordan’s damsel, Teixeirichthys jordani (Rutter, 1897), which is a part of commercial fisheries, exploited by trawl fishery in the southern Taiwan Strait. Therefore, this study would intend to provide the necessary information about the age, growth, and abundance fluctuation for this species to fill the gap in the current knowledge.
Materials and methods.
Age and growth of Jordan’s damsel were assessed based on 407 individuals collected in March–November 2006 from the southern Taiwan Strait. Sagittal otoliths were used for the age determination and growth parameters were estimated by three growth functions. According to the Akaike’s Information Criterion corrected for small sample sizes (AICc), the best fitting model was selected. To explore drivers of the Jordan’s damsel abundance in the southern Taiwan Strait, the Spearman rank correlation was used to discuss linkages between a time series (1994~2010) of catch per unit effort (CPUE) of Jordan’s damsel and several forcing factors: fishing, sea surface temperature anomaly (SSTA), the Pacific Decadal Oscillation (PDO), and chlorophyll-a (CHL).
The fish age ranged from 0 to 3 years; and the estimated growth parameters of the von Bertalanffy model (the best fitting model) were L∞ = 122.19 mm (standard length), k = 0.316 year−1, and t0 = −2.5477. Spearman rank correlation indicated fishing effort (P < 0.000, ρ = −0.826), CHL (P < 0.001, ρ = −0.780), and PDO (P < 0.000, ρ = 0.876) were significant predictors of CPUE between 1994 and 2010, however SSTA was not a significant predictor of CPUE (P = 0.294 > 0.05).
Teixeirichthys jordani displayed positively allometric growth and this study providing population structure (size and age distribution) and growth parameters would be beneficial for population assessment and fishery management for Jordan’s damsel. For Jordan’s damsel in the southern Taiwan Strait, fishing may cause abundance fluctuations by affecting population dynamics, and biophysical conditions associated with PDO and El Niño-Southern Oscillation (ENSO) may be not adequate to affect the stock fluctuation though CHL and PDO were significant predictors of CPUE.
age, growth, abundance fluctuation, Teixeirichthys jordani, Taiwan Strait