How Old Are Our Favourite Great Barrier Reef Animals?

Here’s a fascinating piece of Great Barrier Reef trivia. Have you ever wondered how long marine animals actually live? From turtles and whales to jellyfish and corals, Reef residents span an extraordinary range of lifespans — from just weeks to thousands of years.
Some creatures live fast and disappear quickly, while others quietly persist through centuries of environmental change. Let’s explore the ages of some of the Reef’s most iconic inhabitants.
Sea turtles
Sea turtles are among the Reef’s longest-lived animals, generally surviving for 50 to 100 years. Of the six species found on the Great Barrier Reef, green turtles and leatherbacks may live up to 80–100 years, while loggerhead, olive ridley, hawksbill and flatback turtles typically average 50–60 years. Their slow growth and late maturity make them especially vulnerable to human impacts.
Saltwater crocodiles
Saltwater crocodiles are remarkable for their longevity and resilience. They exhibit negligible senescence, meaning they show few typical signs of ageing such as declining fertility or physical weakness. These apex predators can live for 60 to over 100 years and may continue growing throughout their lives. They can also survive months without food.
Humphead Māori wrasse
The Humphead Māori wrasse (Cheilinus undulatus), one of the Reef’s largest bony fish, typically lives for at least 30 years, with some individuals estimated to reach 50 years. Females may live longer than males, and their slow growth makes populations vulnerable to overfishing.
Humpback whales
Humpback whales generally live for around 50 years, but scientific studies—using earwax analysis—suggest some individuals may live over 90 years. They reach sexual maturity between 5 and 10 years and may migrate, mate and calve for decades. Older whales are thought to play an important role in guiding younger animals during migration.
Coral colonies
Coral colonies are among the longest-living animals on Earth. While individual coral polyps live only 2–3 years, the colonies they form can survive for thousands of years. Some deep-sea corals exceed 4,000 years in age. A black coral (Leiopathes) specimen was estimated to be around 4,270 years old, dating back to the time of Ancient Egypt.
Gobies
Gobies are small Reef fish with short lives, typically 1 to 4 years, although lifespan varies by species. The pygmy goby (Eviota sigillata) holds the record as the shortest-lived vertebrate known, surviving just 59 days. Larger species, such as engineer gobies, may live for over 10 years.
Dolphins
Dolphins usually live 20 to 40 years, though bottlenose dolphins can reach 60 years or more. Many wild individuals regularly live into their forties, with females often outliving males.
Jellyfish
Most jellyfish live for 3 to 12 months, and some species survive only weeks. The notorious box jellyfish typically lives for less than one year, with its adult stage lasting 3–12 months.
From tiny gobies to ancient corals, the Great Barrier Reef is home to animals living on vastly different timescales. Protecting the Reef means protecting not just species, but lifetimes — some stretching far beyond our own.
Contributed with thanks to Tony Fontes

Green Sea Turtle

Photo source: Tony Fontes

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