Fur seal census
Each year Macquarie Island is visited over the summer months by Antarctic Arctocephalus gazella, subantarctic A. tropicallis and New Zealand A. forsteri fur seals. Historically, late February is the time of year when fur seals numbers peak on the island, before dropping off as pups are weened and adults depart for the sea once again. To coincide with the peak in seal numbers the Macquarie Island Fur Seal program, now in it’s 26th year, conducts an annual island census to record the quantity, age class and species of all fur seals on the island’s coastline. This year’s survey was again successful, with initial figures suggesting an overall slight increase in numbers of seals.
In general, counting fur seals sounds like a straight forward task. For much of the coastline this is true, with seals easy to spot on open beaches and on rock platforms within the breeding colonies. Areas closer to the southern end of the island proved trickier, with seals being sighted more intermittently, and found sleeping on top of rock stacks out of sight. The Northern and Southern tips of the island had the highest concentration of the New Zealand Fur Seals, which are the most difficult to count due to their tendency to head for water as soon as they see or smell a person approaching. Trying to get an accurate count means searchers need to move with swift fluid movements across rocks, combined with some stealth and a sharp eye.
The highlight of this year’s census was recording a pup that appeared to have been born at Hurd Point, at the southern end of the island, away from the rest of the island breeding colonies. It is not unheard of, but recording it's birth highlights the value in having the annual census to pick up such things.