A remote island off Victoria's south-west coast, Deen Maar, was once home to Australia's largest fur seal colony. The small rocky island, also known as Lady Julia Percy Island, sits in waters near Port Fairy, 8 kilometres offshore from the tiny town of Yambuk. It is difficult to reach by boat and illegal to visit without a permit. Twenty years ago, the population was thriving, with an estimated minimum of 2,000 seal pups born on the island each summer. Now the population is shrinking, with just 700 pups spotted during a February count. Experts believe hair loss among the seals, which has been linked to pollution, is behind the declining numbers. The Eastern Maar Aboriginal Corporation and Gunditj Mirring Traditional Owners Aboriginal Corporation are the local custodians of the waters around Deen Maar. Eastern Maar's sea country coordinator, Dave Williams, said he became worried about the local seal colony after spotting large patches of fur loss. "When their hair falls out, they can't keep warm, and if they can't spend much time in the water, then they can't feed for as long," Mr Williams said. Australian fur seals have a coarse outer layer of fur that traps air and keeps...