Abstract

The Grouper Moon Project, a collaboration with Reef Environmental Education Foundation (REEF) and the Cayman Islands Department of Environment, has generated nearly two decades of research pertaining to fish spawning aggregations in the Cayman Islands. During this time, the Cayman Island government has made major strides in protecting essential grouper spawning aggregation sites. Survival at early life stages is critical to the recovery and sustainability of these eco-nomic and ecologically important species in the Caribbean. During a 2016 spawning event in Little Cayman, scientists with the Grouper Moon Project collected embryos (Nassau grouper, Epinephelus striatus and tiger grouper, Mycteroperca tigris) in situ at fertilization. Collection from individual spawning rushes (10 Nassau and 6 tiger) allowed for comparison of ma-ternal influence on embryo and larvae survival and condition. Fertilization rate, survival to hatch, larval survival without food and morphological measurements of embryos and larval were measured. Fertilization rate was high (>90%) for both species. Hatch success was consistently high for tiger grouper (98-100%), but varied between females of Nassau grouper (16-98%). Nassau grouper larvae survived without food 4-7 days post hatch (dph) at 26°C and 6-8 dph at 24°C. Tiger grouper larvae survived without food 6-8 dph at 26°C. Overall there was less variability in survival rates between females of tiger grouper and the larvae appear to be more robust to limited food availability at this early life stage. Maternal influ-ence on embryo and larval condition and size may influence hatch success and larval survival, particularly in Nassau group-er

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