Baby reef fishes swim for gold

New research has shown that baby coral reef fishes outperform all other baby fish in the ocean.Adam Downie, the lead author, is a PhD student at James Cook University's ARC Centre of Excellence for Coral Reef Studies (Coral CoE at JCU).Mr Downie stated that young coral reef fishes are the best aquatic athletes. They swim around 15-40 m per second.For comparison, herring babies can swim up to two lengths per minute, while Michael Phelps, the Olympic gold medalist, can swim only 1.4 lengths per minute.Mr Downie stated that swimming performance in baby fishes is related to their association with a reef.A reef fish must navigate the open ocean currents and waters when they are a baby looking for a home. They need to have a greater swimming ability than non-reef fishes in order to be successful at this task."We believe habitat association has shaped swimming performance in the early stages of these marine fishes' lives," stated Dr Peter Cowman (also from Coral CoE at JCU) and Senior Curator for Biosystematics from Queensland Museum’s Project DIG."In our study we compared over 200 marine fish species across their 150-million years of common ancestry. Dr Cowman stated that baby fishes that are able to settle on a reef in later life, regardless of whether they are tropical or temperate, have developed larger muscles and a faster swimming speed than their non-reef cousins.These muscles and organs are developed quickly by the babies of reef fish, which is a sign that they are great athletes. These attributes are not present in other fishes, such as the herring which lives out its entire life in open water."These tiny creatures don't exist as passive particles in the ocean," stated Associate Professor Jodie Rummer from Coral CoE and JCU's College of Science and Engineering. They are highly skilled athletes."Swimming machinery is formed early in a fish’s life. Some do it faster than others.Another study by Mr Downie found that the health of the coral reefs where baby reef fishes live could have an impact on their athletic performance. These young fishes could be deprived of their natural habitats and require more energy to survive. This could lead to problems in their growth, swimming, and other vital activities.Mr Downie stated that while reef fishes can be great swimmers in their early years, their home conditions can have a huge impact on their performance and their ability to become healthy adults.Global coral reefs are being destroyed by climate change, pollution and boat traffic.Dr Rummer stated that future reef fish populations are at risk as a result of the ongoing global coral reef damage.She stated that "compromising the health and well-being of baby fishes is detrimental to the health of adult populations, and thus entire marine ecosystems.""There are approximately 17,000 marine fish species," Mr Downie stated. They are essential for any functioning marine ecosystem, and crucial for fisheries which provide nearly half the world's population with food.He stated that "our findings demonstrate how critical it is to urgently reduce human impact on these fragile species, ecosystems."Healthy reefs are good for fish health and the planet's well-being.###PAPERSDownie A. Leis J., Cowman P. McCormick M. Rummer J. (2021). "The effect of habitat association on swimming performance for marine teleost fish larvae" Fish and Fisheries. DOI: 10.111/faf.12580Downie A., Jones R., Rummer J., Chivers J., Rummer J., Rummer J., Chivers D., Ferrari M., McCormick M. (2021). "Exercising a juvenile reef fish in a degraded coral habitat reduces oxygen uptake rate." Coral Reefs. DOI: 10.1007/s00338-21-02113-xCONTACTAdam Downie (Townsville AEST)P: +61(0) 403 587 0250E: Adam.downie@my.jcu.edu.auJodie Rummer (Townsville AEST)P: +61(0) 439 161 171E: jodie.rummer@jcu.edu.auPete Cowman (Townsville AEST)P: +61(0)490 231 223.E: peter.cowman@qm.qld.gov.auCONTACT US FOR MORE INFORMATIONMelissa Lyne/ Coral CoE, Sydney, AESTP: +61(0)415 514 332E: melissa.lyne@jcu.edu.au