A family got one hell of a shock after taking a photograph on the beach only to realize there was an alarming sight in the background sparking an appeal for information.

If there’s one thing you don’t ever want to see while on the beach – or even more so, in the sea – well, there’s a few things I can think of.

However, one family’s photograph from their day out on a beach between Bonbeach and Chelsea in Melbourne, Australia, reveals one of the number one sights which would likely send you running for your towel, fleeing and never visiting the beach again.

SES Chelsea Unit took to Facebook to share the images last year. The images show one photograph, with the second more zoomed in, revealing what appears to be a dad and child playing on the beach, another parent and their child behind, alongside a dog and two men standing further into the water.

Oh and if you hadn’t already spotted, it’s made sure to circle what appears to be a fin lying not far from all the people pictured too.

The caption to the images reads: “As many of you would be aware, yesterday, we posted about a shark sighting, just off the beach, between Bonbeach and Chelsea.

“Well later, we received a message from a family, who follow our page, who were at Carrum Beach, earlier in the morning. It was their little ones first visit to the beach, and the gentleman’s partner grabbed a couple of snaps to record the day.

“Later, when they got home, and looked at the pictures, they noticed something in the shallow water, just behind them, was this our shark?”

SES Chelsea Unit explains that when they saw the pictures, they weren’t ‘sure’ what the sighting was so contacted several places for their opinions.

“They all agree that although they can’t confirm it’s a shark, they can’t say that it’s not,” the post continues. “So, what do you think. The family are very genuine, and in fairness, they’re the first to admit that they’re not sure what they snapped, but they certainly would like to know. So if anyone has any genuine ideas of what it might be, please let us know.”

And it didn’t take long for people to weigh in with suggestions.

One Facebook user said: “Possibly the banjo shark around Stefan’s ankles that same day?”

“Let’s say it’s a 20cm dorsal fin, for size percent based on bronze whaler that’s only a 1.5 – 1.8m shark. If it’s a 30cm dorsal that’s a 2.3 – 2.6m shark which on one that big would be a belly to bottom of dorsal height of about 45cm swimming in 60cm of water. So a 1.8m shark of that species with a fairly slender belly could easily go unnoticed and would have been far too small to take a German Shepard let alone a person,” another added.

However, a third commented: “A dog… it’s a dog.. Ps banjo sharks are not actual sharks, they are a Ray.”

A fourth said: “I mean this is not a small shark, but a baby whale. Shark is not that dark. Something is.”

“It’s the back of someone’s head who is laying down in the shallows,” a fifth theorized.

And a final simply resolved: “Better to be safe than sorry.”

So, what do you think?