Tourists visit a Adélie penguin colony on Brown Bluff in Antarctica, in this undated photo.

The increase in Antarctic tourism has put pressure on the continent's wildlife, experts say.

During the height of summer tourist season, for example, boats visit the same penguin colony day after day.

The influx of tourists has forced many members of the Antarctic and Southern Ocean Coalition to consider a mandated cap on people allowed to visit Antarctica each year.

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