This week at Macca, an insight into the annual Elephant Seal census.

Count All The Seals!

Spring is my favourite time at Macquarie Island. After the long, lonely, icy and windy months of winter darkness, the island explodes with animals. The gentoos start nesting in the tussocks, the giant petrels are ravenous as they search for food for their young, the king penguins can stop shivering quite so much on the beaches, and of course the main event of spring – the elephant seal breeding begins.

The start of the season is heralded by the arrival of the bulls. These would-be beachmasters have spent the last nine months fattening up on the fish and squid they can catch as they gain bulk for the battles and their long fast that starts on arrival. These big boys with probisci ranging from the new trunk through to the battled scarred full length take up their positions on the beach. Even before the cows arrive the deadly battles began, with might being right for who controls that section of beach. Each day we saw new winners and losers, though it was hard to tell who was who as most bore fresh wounds and a tired expression as they lounged on the beach. Next to arrive were the cows. Heavily pregnant, these mums have spent their winter at sea growing their pup and feeding up for their 6-8 week fast on shore. Initially there were a handful of arrivals each day, but the harems rapidly filled up util barely any spare sand was available on shore.

This marked the start of my adventure. Tasmanian Parks and Wildlife have conducted elephant seal surveys on Macquarie Island since the 1980s. Every weekend the harems on the East and West coast of the isthmus are counted. We count every cow, and every dead pup as a proxy for the cows (who return to sea if their pup dies). For 10 days around the peak of the season it’s all hands to help out with the daily counts of the East and West harems. On the census day, the 15th October, selected sites around the island are counted. Every 5 years the aim is count the whole island. I eagerly put my hand up for as many seal counting sessions as I could fairly take.

I love the absolute drama and chaos of the elephant seal census. It’s brilliant to observe the animals and see the stories of their lives play out – cows fighting as they battle for room in the crowded beach, the kennel call of multiple pups barking for their mums and the cows answering, bulls suddenly charging through the harem sparking absolute chaos as they chase away a contender or fight to get the ‘friendly flipper’ with a cow heading out to sea. All keenly observed by skuas only too happy to play midwife as they look for morsels of placenta and deceased pup. The giant petrels are also keen members of the clean up crew. We had two bulls die on the isthmus, and with their powerful beaks they made short work of the much-anticipated meal nature provided them.

Our 10 days of non-stop action has passed, and we’re now back to the weekly count until the end of November. While it’s a bit quieter and the harems are getting smaller, there is cuteness overload with the fat little weaners lounging on the beach. By the end of the month these weaners will have learnt to swim and start to head out to sea. Then cycle will begin for another year, and next years crew will get witness the magic!

- Dr Kate Kloza | Expedition Medical Officer | 76th ANARE, Macquarie Island 2023.