Variable temporal relationships between environment and recruitment in coral reef fishes

Abstract

Studies of coral reef fish recruitment have focused more on factors influencing the return of larvae to reefs and the process of settlement than on factors affecting survival in the plankton, despite the well-documented importance of the larval environment for temperate marine species. We examined the ability of environmental factors to explain temporal patterns of recruitment in 8 taxa of coral reef fishes, distinguishing variables associated with settlement from those associated with the pelagic larval stage. At 10 d intervals over a 17 mo period, we collected newly settled fishes from settlement units in Barbados (West Indies). We collected concurrent data on 3 settlementassociated variables, lunar darkness, wind speed, and tidal amplitude, and 5 larval environment variables, sea-surface temperature, cloud cover, salinity, chlorophyll a concentration, and normalized water-leaving radiance at 555 nm. The last 3 were associated with low-salinity intrusions originating in the Amazon. We used hierarchical partitioning and Mallow's C(p) model selection to identify important variables for each taxon. Temporal patterns of recruitment differed among taxa of which 6 showed significant environmental correlations. Significant settlement variables included lunar darkness and tidal amplitude. Significant larval environment variables were diverse and varied in magnitude and sign across taxa. The effects of larval variables were generally strong relative to settlement variables. The temporal scale of the strongest environmental predictor differed across taxa. Our study supports the views that planktonic factors affecting larval survival substantially influence recruitment in coral reef fishes and that different species are affected differently by a common, temporally variable, planktonic environment.KEY WORDS: Settlement · SMURF · Rubble · Pomacentridae · Labridae · Serranidae · Scaridae · Gobiidae Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 379: [225][226][227][228][229][230][231][232][233][234][235][236][237][238][239][240] 2009 Less attention has been given to factors influencing survivorship of coral reef fishes throughout the pelagic larval duration (hereafter, larval environmental variables, LEV), which have been a prominent focus of fisheries research in temperate marine systems (Anderson 1988, Heath 1992, Leggett & Deblois 1994. Studies on temperate species suggest that relevant LEV would include physical and chemical aspects of the larval environment (e.g. temperature and salinity; Fukuhara 1990, Watanabe et al. 1999, food availability (e.g. Beaugrand et al. 2003 and references therein) and predation (review in Bailey & Houde 1989). For coral reef fishes, experimental studies show that small changes in water temperature have important effects on larval traits, such as larval duration, swimming and growth (Green & Fisher 2004). These are traits likely to affect larval survival in the field (Houde 1987, Anderson 1988. Field studies of coral reef fishes ...

Spatially variable larval histories may shape recruitment rates of a temperate reef fish

“…However, other studies have failed to find support for such relationships (e.g. Leggett & DeBlois 1994, Sponaugle et al 2006, and a recent study by Vallès et al (2009) documents substantial variability in relationships between larval environmental features and recruitment across several species of coral reef fish.…”

“…Similarly, many ecological studies highlight important linkages between conditions experienced by larvae in more offshore environments and the magnitude of onshore recruitment strength (e.g. Gaines & Roughgarden 1987, Wilson & Meekan 2001, Bergenius et al 2002, Lemberget & McCormick 2009, Vallès et al 2009). …”

“…This spatial structure also implies that the larvae recruiting to different local populations may have experienced different developmental environments (Shima & Swearer 2009), and consequently, that relationships between conditions in the larval environment and recruitment strength may be spatially or temporally variable (e.g. Vallès et al 2009). …”

Ocean acidification disrupts the innate ability of fish to detect predator olfactory cues

“…Reef fish larvae typically settle at night when visual predator recognition is likely to be less effective. Furthermore, many reef fish settle around the new moon (Valles et al. 2009), when light levels for visual predator detection are at their lowest.…”

Wind Conditions on the Great Barrier Reef Influenced the Recruitment of Snapper (Lutjanus carponotatus)

“…High variability in recruitment, both within and among seasons, appears to be typical of many coral reef systems (e.g., Doherty, 1987;Tolimieri et al, 1998). A comprehensive understanding of recruitment variability can be attained through investigating the conditions present when successful recruits were known to be in the plankton (Sponaugle and Pinkard, 2004;Valles et al, 2009). Accordingly, the causal factors of recruitment variability could be investigated by forcing a biophysical model with the conditions present during the pelagic larval phases of successful recruits.…”