WELCOME TO SCIENCE MISS SAUNDERS LET’S BEGIN THIS SESSION BY YOU TELLING ME ABOUT WHAT YOU HAVE LEARNT ABOUT THE NASSAAU GROUPER SO FAR… LIFE CYCLE OF THE NASSAU GROUPER WHAT IS THE VALUE OF THE NASSAU GROUPER TO THE BAHAMAS? WHAT IS THE VALUE OF THE NASSAU GROUPER TO THE BAHAMAS? 1. LIST THE STAGES OF DEVELOPMENT FOR THE NASSAU GROUPER 2. RELATE EACH STAGE TO DIAGRAMS AND LOCATIONS 3. DESCRIBE SPAWNING AGGREGATION Let’s begin with a video….. https://www.youtube.com/watch?v=caXbtD_XYts What is a life cycle? • The series of changes in the life of an organism including reproduction. • All animals, including humans, are born, they get older and bigger, and some will go on to have children. In the end, all animals die. We call this a life cycle. • Animals are small when they start life. Over time they grow bigger, and their bodies change. • When they are grown up, they might reproduce and have young The Nassau Grouper • The Nassau Grouper goes through 5 stages of development. • The life cycle begins during mating season which is during the full moon of the winter months (late November through February) when water temperatures are cool. • Fertilization is external, meaning that it occurs outside of the female’s body. • This happens when females release their eggs into the water followed by the release of sperms by the males. • Fertilization can occur in this way because Nassau Groupers gather in one area for mating, and that millions of gametes (sex • When aggregating, Nassau grouper show three color “phases,” or patterns, along with their normal coloring. • Their courtship takes place according to these phases. • It ends near sunset, with a group of them swimming upward quickly; a female in the lead releases eggs, while the males behind her release sperm. • Fish move in groups of 25 to 500. • They travel parallel to the coast or along the shelf edge. • Movements are synchronous. • They return to their home reefs after spawning. READY TO RELEASE.. • White belly - females in the normal color phase but with white abdomens swollen with ova (eggs). SPER M CLOU D WHEN EGG AND SPERM CELLS ARE RELEASED, IT CAN BE SEEN LIKE A Life Cycle STAGE 1: FERTILIZED EGG • DURING SPAWNING RUSH, THOUSANDS OF EGSS ARE RELEASED AND FERTILIZED. • THESE ARE USUALLY FOUND IN THE WATER COLUMNS STAGE 2: EARLY LARVAE • THE EGGS HATCH WITHIN 48 HOURS INTO PELAGIC LARVAE. • THESE LARVAE FLOW WITH THE OCEAN CURRENT AND ARE FOUND IN THE OPEN OCEAN STAGE 3: LATE LARVAE • THE NASSAU GROUPER STAYS IN THE LARVAL STAGE FOR 35 TO 40 DAYS BEFORE TURNING INTO JUVENILE FISH. • THEY REMAIN IN THE OPEN OCEAN JUVENILE GROUPE R • AFTER ABOUT A MONTH, THE FISH IS NOW A JUVENILE GROUPER, • THEY BEGIN TO FLOAT ON CURRENT AND SETTLING EVENTUALLY IN SEAGRASS AND ADULT • THE NASSAU GROUPER MAY TAKE 4 TO 8 YEARS TO REACH SEXUAL MATURITY • ONLY ABOUT 1% OF EGGS FERTILIZE REACK THIS STAGE LET’S LOOK AT THE STAGES… • I & J= EARLY LARVAE • K = LATE LARVAEA • L = JUVENILE • M= ADULT WHAT HAVE YOU LEARNT?
