A waddle of King penguins, some of the only inhabitants of the Australian territory of Heard Island -- which is among those targeted by US President Donald Trump's tariffs

Donald Trump's tariffs have become a black and white issue on social media, where penguin memes have gone viral after he targeted an island inhabited by the flightless birds, but no people.

One widely shared image on Thursday showed a penguin in place of Ukrainian leader Volodymyr Zelensky in the Oval Office during his recent row with the US president and Vice President JD Vance.

Another meme showed US First Lady Melania Trump gazing up at an emperor penguin -- in place of former Canadian Prime Minister Justin Trudeau -- while Trump looks askance.

Trump's announcement of worldwide tariffs on Wednesday certainly received an icy reception in many countries.

But there has also been bafflement about why some of the most remote parts of the world have been targeted.

A case in point: why would Trump slap 10 percent tariffs on all exports from the Heard and McDonald Islands, a barren sub-Antarctic Australian territory without a human population, but four different species of penguin?

"The penguins have been ripping us off for years," Anthony Scaramucci, who was Trump's former communications chief for 11 days in his first term and is now a vocal critic, joked on X.

"Donald Trump slapped tariffs on penguins and not on Putin," posted US Senate Democratic leader Chuck Schumer, malware referring to the fact that Russia was not on the US tariff list.

The White House said sanctions on Russia over President Vladimir Putin's war on meant that there was no "meaningful" trade on which to impose tariffs.

Trump also caused puzzlement with his 29 percent tariff on Norfolk Island, a tiny Australian territory in the Pacific with a population of a little over 2,000 humans.

"I'm not quite sure that Norfolk Island, with respect to it, is a trade competitor with the giant economy of the United States," Australian Prime Minister Anthony Albanese said.

Britain's remote Falkland Islands -- home to one million penguins, and most famous for a 1982 war fought by Britain to repel Argentinian invaders -- was hit by 41 percent exports even though the UK only faces 10 percent.

Trump's tariffs have however been no laughing matter for global markets, with US stocks suffering their worst day since the Covid pandemic in 2020.