Variation in larval growth can predict the recruitment of a temperate, seagrass-associated fish

Abstract

Understanding the factors leading to inter-annual variation in recruitment of animals with complex life cycles is a key goal for ecology and the sustainable management of animal resources, such as fisheries. We used otolith microstructure to determine larval growth rates of post-larval King George whiting, Sillaginodes punctata, in seagrass beds of Port Phillip Bay, Australia. Inter-annual variation in growth determined early in the pelagic, offshore larval-stage was highly correlated with post-larval abundance (a predictor of fishery recruitment). Sea surface temperature measured near the presumed spawning area off Western Victoria was significantly correlated with larval growth, and was also significantly correlated with post-larval abundance in Port Phillip Bay. Increased water temperature would have had the direct effect of increasing larval growth and therefore contributing to larval survival, but may also have been indicative of enhanced physical transport and/or plankton productivity. Overall, larval growth rate of King George whiting is a very strong predictor of post-larval abundance, which in turn will influence fishery recruitment in 3-5 years' time.

Ontogeny of in situ behaviours relevant to dispersal and population connectivity in larvae of coral-reef fishes

“…Recent evidence from several systems and a variety of species indicates that the fastest growing individual larvae may be the ones that survive to settlement (e.g. Vigliola & Meekan 2002, Jenkins & King 2006. Therefore, it may be the best performers in other areas, such as swimming speed, that preferentially survive to reach a settlement site, and, if so, the exceptional performers should be the focus of considerations of dispersal and connectivity.…”

Growth- and size-selective mortality in pelagic ­larvae of a common reef fish

“…Larval stages are typically subject to high mortality rates, and survival is often related to early life history traits such as fast growth and large size-at-age (Houde 1989, Meekan & Fortier 1996, Hare & Cowen 1997, Shoji & Tanaka 2006, Takasuka et al 2007). Larval traits can also influence recruitment success (Bergenius et al 2002, Jenkins & King 2006) and survival during the subsequent juvenile phase (Searcy & Sponaugle 2001, Allain et al 2003, McCormick & Hoey 2004, Macpherson & Raventos 2005, Gagliano et al 2007). Understanding survival during larval life is an essential component of quantifying larval transport, recruitment success, and connectivity of marine populations (Cowen & Sponaugle 2009).…”

Observed and modeled larval settlement of a reef fish to the Florida Keys

“…To more directly examine the physical and biological mechanisms associated with settlement, process-oriented studies have correlated relatively short time series of larval supply or settlement with particular climatological (Shenker et al 1993, Milicich 1994, Thorrold et al 1994, Kingsford & Finn 1997, Lo-Yat et al 2011 or physical oceanographic events (Cowen 2002, Sponaugle et al 2005, D'Alessandro et al 2007. Others have related large pulses of settlement to larger hatch sizes of larvae (Macpherson & Raventos 2005), faster larval growth (Bergenius et al 2002, Jenkins & King 2006, Sponaugle et al 2006, larger larval size-at-settlement (Wilson & Meekan 2002), or larvae of higher condition/ lower stress ). Similarly, spatial variation in patterns of fish settlement has been related to spatial variation in onshore flow or current speeds (Sponaugle & Cowen 1996, Paris et al 2002, Schmitt & Holbrook 2002.…”