If you are having a bad day and need a quick pick-me-up, this photo of "the happiest animal on earth" seemingly asking for a hug may just do the trick.

The irresistibly adorable shot of a quokka is the latest #quokkaselfie to capture hearts on Instagram.

The photo, first posted by Instagram user Campbell Jones on the photo-sharing platform on Jan 26, shows the Australian marsupial leaping towards the camera, with what appears to be a smile on its face.

Mr Jones, 21, took the shot in January on his first trip to Rottnest Island, The West Australian news site said in a report on Monday (Feb 27).

He was cycling with his girlfriend when he went past a quokka and got off to get a photo with it, he told Sunrise Perth News.

The photo has since gone viral and has been reposted many times by smitten users.

Rottnest Island, off the coast of Western Australia, is reportedly the "last stronghold" of quokkas and is home to 8,000 to 12,000 quokkas, according to the official Rottnest Island website.

The herbivorous creatures, which are about the size of a cat, are protected animals.

The quokka is said to be curious, unafraid of humans and harmless - traits that perhaps have earned it the title of "the happiest animal on earth".

The hashtag #quokkaselfie is a popular one on Instagram, with more than 11,000 shots of people with the friendly creatures.

However, visitors to the island are reminded in a video by Rottnest Island posted on YouTube in September last year (2016) not to touch or feed the wild animals.

According to Rottnest Island's website, anyone who deliberately interferes with wildlife on Rottnest Island - including feeding - can be fined A$150 (S$162) under the Rottnest Island Authority Act 1987, and potentially fined up to A$10,000 under the Wildlife Conservation Act 1950.

Those found guilty of acts of animal cruelty can be fined up to A$50,000 and jailed for up to five years.