Massive Iceberg Hits 2-Year-Old Penguin Refuge, Clarence Island in Antarctica, No Birds Were Hurt

In what could be described as "perfect timing," no birds were harmed when a sizable iceberg struck Clarence Island's two-year-old penguin refuge in Antarctica.

Massive Iceberg on the Loose

A massive iceberg, about half the size of Rhode Island, recently collided with an Antarctic penguin refuge, which was formed two years earlier from a similar collision. This massive tabular berg, known as D-30A, measures approximately 45 miles in length and 12.5 miles in width, being the largest remnant of D-30.

D-30 was born in June 2021 when its parent berg, D-28, hit land near the Borchgrevink Ice Shelf in eastern Antarctica, splitting into two. D-30A slowly drifted west along the Antarctic coast.

In late 2022, D-30A abruptly changed course and headed for Clarence Island, the easternmost of the South Shetland Islands, despite its much smaller size. It collided with the island's southern coast on September 6, sandwiched the penguin refuge, then spun eastward and eventually departed. Fortunately, the impact caused minimal damage.

Clarence Island and Its Penguin Refuge

Clarence Island hosts a crucial breeding ground for chinstrap penguins, boasting 100,000 breeding pairs each winter. Recent concerns arose when an iceberg collided with the island, potentially impacting this population. Fortunately, timing played in favor of the penguins; they hadn't returned to the colony yet, averting a serious catastrophe.

Heather Lynch, a statistical ecologist from Stony Brook University, emphasized this stroke of luck, highlighting the potential devastation if the collision had occurred a few months later when the penguins were present.

Iceberg collisions with islands can disrupt wildlife significantly, particularly if they become grounded around these isolated landmasses. These ice formations hinder marine creatures from foraging at sea, alter local water temperature and salinity, and obliterate seafloor ecosystems while disturbing the broader food web dynamics. Thankfully, in this case, the penguins escaped a potentially disastrous encounter.

Colliding Icebergs

In late 2020, a major concern arose when the world's largest iceberg, A-68A, seemed poised to collide with South Georgia in the South Atlantic Ocean, a crucial refuge for penguins and seals. Experts feared it might become grounded, remaining there for years. Miraculously, just in time, the colossal iceberg altered its course, bypassing the island before breaking into several pieces.

Clarence Island's unique seafloor likely played a vital role in preventing a catastrophe, as its depth made it less probable for D-30A to become stuck. Christopher Shuman, a glaciologist from the University of Maryland and NASA's Cryospheric Sciences Laboratory, explained that the eastern side of Clarence Island's sheer drop-off allowed the iceberg to pass through.

Nevertheless, had the iceberg lingered, it could have posed severe problems for nesting penguins. While incubating their eggs, these birds rely on partners to hunt for food. Even a brief disruption in access to the colony could have resulted in a failed breeding season, highlighting the delicate balance of nature.

The Plus Side

The frightening close encounter may actually be advantageous for the local fauna as a result. According to researchers, as D-30A crossed the island, it likely produced meltwater that was iron-rich and could have helped the local algae population expand.

D-30A currently appears to be traveling through the Drake Passage, also known as "iceberg alley," where enormous icebergs are dragged into warmer waters and drown. The former largest iceberg in the world, A-76A, was first detected in this waterway in November 2022 and eventually disintegrated 1,500 miles further north in June of this year.