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Groucho the Seal to gain 100kg

  • Thursday 25th July 2013




Our popular resident seal is expected to stack on a whopping 100 kilos over the winter months to help keep warm and get in top seal shape for the breeding season.

Groucho, our largest male seal is expected to tip the scales at 260 kilos by September.


UnderWater World Mammal Manager Mark Ryan said seals naturally experience physical and behavioural changes during the colder months as they become more active and require more food.


“As the seals become more active, their dietary needs begin to change and the team carefully calculate the amount of additional food they require. Groucho eats an average of 10 kilos of fish daily throughout most of the year and needs an additional 15 kilos of fish per day during winter to maintain a healthy lifestyle. The animal care team at UnderWater World increase food intake to a total of 65 kilos of fish between seven seals every day,” he said.


“It’s something that only happens in winter making it remarkable to see the seals, especially Groucho, reach their peak weight and put on one hundred kilos which is equivalent to the weight of five average six year old kids!”


Groucho, who has been here at UnderWater World since 2000, arrived weighing only 11.5 kilos and is expected to put on the most weight during June, July and August.  Groucho will then naturally shed the weight over the summer months.

So come on in and see Groucho and all our amazing seals as they reach their peak size, which occurs only during the winter season!


There are three different species of seals at UnderWater World including the Australian Fur Seal, Australian Sea Lions and New Zealand Fur Seals who all reside in the attraction’s Seal Island.

Mr Ryan said it is common for the three species of seals to experience seasonal changes including weight gain, not only to keep warm but to also prepare them for the breeding season in the spring.


“It is especially common for the male seal to put on weight in winter before the breeding season because it gives him a greater chance to have more mates. The larger the male seal is the more chance he has at defending a larger territory from other bulls,”