A five-foot Blue shark (Prionace glauca) has caused New Jersey lifeguards to close a beach after it came too close to shore for comfort.
Video footage from a holidaymaker clearly shows the creature swimming close into the beach at the Seaside Park, and apparently floundering in the surf before heading back out to sea.
While swimmers may have been somewhat alarmed by the proximity of the shark, beach control officials were more philosophical, commenting that "they're out there all the time feeding on dead fish, but this one just happened to come in closer than normal."
This is the third time in recent weeks that shark sightings in the area have led to beach closures.
Blue sharks
In late July, a pair of Blue sharks was spotted just outside the surfline at a nearby beach, prompting lifeguards to remove swimmers from the water.
While some experts think the sharks’ behaviour may be down to injury or sickness, others believe it is due to unseasonably high sea temperatures.
Shark expert George Burgess from the University of Florida suggested that warmer waters may have increased the numbers of food fish present, which in turn has attracted their larger predators.
"These could be sharks that are normally there in September, when nobody is in the water to see them," explains Dr Burgess.
Shark sightings
While shark sightings often conjure up Jaws-like images, the likelihood of being attacked by a shark is very low. In the US, there are around 16 shark attacks each year and fewer than one fatality every two years.
In reality, man poses a far greater danger to sharks: more than a quarter of all shark species are exploited by humans, and half of all shark species are listed as endangered on the IUCN Red List.
However, despite the scare, Blue shark attacks are actually uncommon and the species is not usually considered a particular danger to humans.