A few weeks ago, people in Iluka were surprised to see a leopard seal on one of the town’s pretty beaches.
Scientists said the animals weren’t normally seen that far north and warned people to stay away – with razor sharp teeth and a volatile disposition, getting too close to the leopard seal would be dangerous.
But a week or two later it was seen again further north at Lennox Head. Scientists said it looked like it had suffered a hard time since its previous stop in Iluka. They said it didn’t look well at all, skinny and sick.
More recently, its remains were found washed up on the beach at Broken Head in Byron.
But Byron Bay marine biologist Dr Mary Gardner says it isn’t that surprising to see a leopard seal so far from home.
Whereas scientists once thought leopard seals only ate penguins and fish, it turns out they also eat krill, the main source of food further away from coastal areas.
‘The young males like to roam, just like young people like to travel the world,’ she told Bay FM listeners last week, ‘they’ll go to South Africa, so on that basis, perhaps it’s not that surprising to see this sea leopard here at Broken Head’.
Can sea leopards learn to love land again?
Females usually carve out a hole in sea ice for their babies but with less sea ice compared to ten years ago, scientists have been wondering how the species will survive if they fail to figure out how to give birth on land.
But it seems sea leopards can change their spots.
Dr Gardner says a research project involving citizen science in New Zealand has documented over 3,000 sightings of leopard seals.
Females have also been known to travel further than previously thought.
‘The females, when nursing, will eat fur seal pups so they will have enough milk’, Dr Gardner says.
Studies of ancient ice show the animals have been living on New Zealand for more than a thousand years, suggesting the shift to sea ice may have been more recent than previously thought.
But so far, scientists haven’t figured out when the change happened and sea leopards have been using the sea ice holes for as long as records date.
Seals on the other side of the world have similar methods and pups without nesting holes there are at risk of being eaten by polar bears roaming the ice in desperate search of food.
‘This is partly a climate change story and also partly a story of animal resilience,’ Dr Gardner says of the sea leopard return to land.
You can hear a full interview with Dr Mary Gardner via Bay FM’s Community Newsroom.
This article has been updated with a correction: Dr Gardner says there are three months less sea ice available now compared to a decade ago, not ‘three months’ worth of sea ice left’, as previously written.
Here’s a link that should get you to Mary Gardner’s audio interview.
http://programs.bayfm.org/community-newsroom/2019-10-04
Thanks Tim, the link in the article has also been fixed 🙂
Great to see the interest in this story — I was going to write it up for the Echo and it’s been done for me! A few corrections though–
1. not ‘3 months sea ice left’ but ‘3 months less sea ice now compared to a decade or so ago
2. not ‘females go after males’ but females when nursing will eat fur seal pups so they will have enough milk’
3. the vagrants or residents question: In Aotearoa/NZ the records and sightings of leopard seals are around 3,000 3 births on land 34% juveniles the rest adults including a resident in Auckland Harbour marina! The status of leopard seals is now changed from vagrant to resident, giving new protection. The middens show bones from 1200 AD: possible that the leopard seals headed south and far south as colonialists commercialised seal hunting and wiped out populations of fur seals that the leopard seal would hunt. now, as protection sees new expansion in fur seal populations, the leopard seals return.
4. Australian shores may be of interest to leopard seals and a citizen science project would be important to observe changes in vagrancy/residency status for leopard seals.
Thanks Mary will fix those first two points and might leave the extra detail re NZ and call for an Aussie citizen science project to you in case you want to write a follow-up piece which might be nice, especially if you can get pics of the NZ leopard seals which I couldn’t find.