Variations in early life history traits of Japanese anchovy Engraulis japonicus in the Yangtze River Estuary

Abstract

Resources of Japanese anchovy (Engraulis japonicus Temminck & Schlegel, 1846) are undergoing dramatic recessions in China as the consequence of intensifying anthropogenic activities. Elucidating the influences of local-scale environmental factors on early life history traits is of great importance to design strategies conserving and restoring the declining anchovy resources. In this research, we studied hatching date and early growth of anchovy in the Yangtze River Estuary (YRE) using information obtained from otolith microstructure. Onset of hatching season and growth rates of anchovy was compared to populations in Japan and Taiwan. In YRE, the hatching date of anchovy ranged from February 26th to April 6th and mean growth rate ranged from 0.27 to 0.77 mm/d. Anchovies hatching later had higher growth rates than individuals hatching earlier before the 25th day. Among populations, hatching onsets of anchovy from the higher latitude were later than populations in the lower latitude, and growth rates of anchovy in YRE were much lower than populations in Japan and Taiwan. Variations in hatching onsets and early growth patterns of anchovy thus provide important knowledge on understanding the adaptation of anchovy in YRE and designing management strategies on conserving China’s anchovy resources.

Evaluation of Yellow Sea anchovy (Engraulis japonicus) fishery for management strategies using a data-limited management toolkit

“…Japanese anchovy juveniles demonstrated different growth patterns on different spawning dates and among groups in the Yangtze River Estuary in China [ 34 ]. And this feature was also found on the European anchovy with a clearer age range (40–60days) [ 35 ], belonging to the same genus as Japanese anchovy, which showed different growth between Tyrrthenian Sea and Strait of Slicily of the Mediterranean [ 36 , 37 ], and the fat content also showed large monthly changes in 2004 and 2005 in the Yellow Sea of China [ 37 ].…”

Age and Growth of Japanese Anchovy (Engraulis japonicus, Temminck & Schlegel, 1846) in Coastal Waters around Shandong Peninsula, China

“…There are several traditional spawning grounds for anchovies along the coast of the Shandong Peninsula (Figure 2), which play a pivotal role as both spawning and feeding grounds for the anchovy population [17,23,24]. Several studies have been conducted to investigate the biological information of anchovies around these areas [14,[25][26][27][28]. However, these studies are relatively limited and dated, emphasizing the need for further studies to address knowledge gaps.…”

Spawning strategy of Japanese anchovy Engraulis japonicus in the coastal Yellow Sea: Choice and dynamics

“…The Japanese anchovy Engraulis japonicus is one of the most abundant small pelagic fish species and is widely distributed in the western North Pacific (Hayashi et al., 2016; Lee & You‐Bong, 2005). Until now, most studies of the environment‐related spawning of the Japanese anchovy have been undertaken on the Pacific side (Funamoto et al., 2004; Itoh et al., 2009; Oozeki et al., 2007; Takasuka, Oozeki & Kubota et al., 2008; Takasuka, Oozeki, Kubota & Lluch‐cota, 2008; Takeshige et al., 2015), while few have discussed the spawning dynamic of Japanese anchovy in term of a comprehensive perspective in the Yellow Sea, where the stock size is even larger (Iversen et al, 2001; Liu et al., 2018; Wan et al., 2002; Wan, Zhao et al., 2008; Wei et al., 2003; Zhao et al, 2003). The total annual catch of Japanese anchovy in China has fluctuated between 50 and 120 metric tonnes since the mid‐1990s, accounting for 70% of world production (Figure 1).…”