The biggest threat to a colony of more than one million chinstrap penguins in the subantarctic right now isn't from below, it's from above.
An erupting volcano on Zavodovski Island, part of the South Sandwich archipelago has scientists worried about what the ash clouds could mean for the species which resides there.
Mt Curry, on the north of the island, has been erupting since March this year.
The British Antarctic Survey (BAS), which recently re-mapped the chain of volcanic islands, was told of a large 7.2 magnitude earthquake which hit the area in June.
Satellite imagery confirmed not one, but two volcanoes in the South Sandwich Islands were erupting - Mt Curry and Mt Sourabaya on Bristol Island to the south of the group.
Mt Curry erupting on Zavodovski Island taken by fishing observer David Virgo (BAS)
Photos taken by fishing vesels in the area captured the ash clouds on the island which showed the main vent was on the western side. However, the prevailing wind was blowing it to the east which is where the colony of chinstraps is. It's the largest grouping in the world and shares the area with around 180,000 macaroni penguins.
Satellite photos showed between one third and half of the island has so far been covered in ash.
Researchers were concerned about the time of year the eruption was happening. The adult penguins were in the process of moulting - that is, shedding their old feathers for new ones which meant they couldn't leave the island.
"We don't know what impact the ash will have on the penguins. If it has been heavy and widespread it may have a serious effect on the population," BAS geographer Dr Peter Fretwell says.
BAS penguin ecologist Mike Dunn says the ash could be significant for the penguins.
"When the penguins return to breed later in the year, it will be interesting to see what impact this event has on their numbers."
Two scientific expeditions are scheduled to visit the area later this year which will look at the impact the eruption has had.
No humans live on Zavodovski Island which is part of 10 others in the group - all of which are of volcanic origin.
The BAS says this is the first time an eruption on Zavodovski Island has been seen, though there's evidence it happened in the 1970s and potentially in the 1980s and as late as 2012.
South Georgia and the South Sandwich Islands are a British Overseas Territory.