Understanding the life history strategy of species can clarify their functional role, and contribution to the productivity and resilience of an ecosystem. We use otolith microstructure analysis to study the life history of 2 widespread and abundant Caribbean reef fishes, genetically identified here as the glass goby Coryphopterus hyalinus and masked goby C. personatus. Our analysis reveals that these species exhibit an extreme life history relative to other vertebrates due to their short lifespan, small adult body size, early maturity, and continuous growth in body length throughout reproductive age. We find that pelagic larval duration (PLD) varies widely, and average larval growth influences PLD where faster-growing larvae have shorter PLDs. We show that average daily growth substantially decreases during the settlement transition to reef habitat, approximately coinciding with reproductive maturity. Continuous somatic growth throughout reproductive age can serve to support greater fecundity in older, larger-bodied females and enhance survivorship. Several features of the ecology (i.e. broad depth range, planktivorous diet) and life history (i.e. small adult body size, quick generational turnover, short lifespan) of C. hyalinus and C. personatus indicate that they play a key trophic role in transferring nutrients from pelagic plankton to Caribbean reef predators and the reef benthos. Our analyses highlight why life history traits related to survival, reproduction, and population dynamics can enhance our understanding of ecosystem-scale processes and functioning on coral reefs.

Video cameras recorded the diurnal visitation rates of transient (large home range) piscivorous fishes to coral patch reefs in The Bahamas and identified 11 species. Visits by bar jack Caranx ruber, mutton snapper Lutjanus analis, yellowtail snapper Ocyurus chrysurus, barracuda Sphyraena barracuda and cero Scomberomorus regalis were sufficiently frequent to correlate with a range of biophysical factors. Patch-reef visitation rates and fish abundances varied with distance from shore and all species except S. regalis were seen more frequently inshore. This pattern is likely to be caused by factors including close proximity to additional foraging areas in mangroves and on fore-reefs and higher abundances close to inshore nursery habitats. Visitation rates and abundances of C. ruber, L. analis, O. chrysurus and S. regalis also varied seasonally (spring v. winter), possibly as fishes responded to temperature changes or undertook spawning migrations. The abundance of each transient predator species on the patch reefs generally exhibited limited diurnal variability, but L. analis was seen more frequently towards dusk. This study demonstrates that the distribution of transient predators is correlated spatially and temporally with a range of factors, even within a single lagoon, and these drivers are species specific. Transient predators are considered an important source of mortality shaping reef-fish assemblages and their abundance, in combination with the biomass of resident predators, was negatively correlated with the density of prey fishes. Furthermore, transient predators are often targeted by fishers and understanding how they utilize seascapes is critical for protecting them within reserves.