"The bites are often small but the reaction can swell to the size of a 20 cent piece or bigger."
Mount Maunganui pharmacist Mark Bedford of Amcal Mount Dispensary has been researching the Mount Mauler for the past 14 years and believes its scientific name is phycosecis limbata.
"It's in full season now. They are in their larvae stage between November and February and that's when most people are at the beach," he said.
"Then after that [the bugs] grow into black beetles and fly away."
Mr Bedford said the larvae tended to live in the soft sand at the bottom of the dunes, meaning it was best for beach-goers to sit below the high tide line.
The bug bites were not painful or noticeable when they were occurring.
But two or three days later, itchy welts appeared on the skin, he said.
A general antiseptic or antihistamine cream would relieve minor cases but infected bites could mean a trip to the doctor for steroid cream.
Although they were dubbed the Mount Mauler, Mr Bedford believed the bugs were a menace on all East Coast beaches.
Meanwhile, tens of millions of clear, squishy organisms are washing up along the Western Bay coastline.
According to Bay of Plenty Polytechnic marine studies tutor David Guccione, the clear, globular masses were not baby jellyfish or jellyfish eggs but a collection of organisms called salps.
"Salps are the fastest reproducing animal in the ocean. They are multi-cellular organisms, each one of the little balls is an animal that reproduces asexually and they combine to form long chains," he said.
"They're important [to the marine ecosystem] in that they take lots of carbon dioxide out of the atmosphere because they graze near the surface and then their droppings, which are rich in carbon, get deposited on the ocean floor in sediment."
Salps are about the size of an old 5c piece and generally live in deep ocean water. However, wind and sea currents push them to shore. Mr Guccione said they were most prolific in temperate and polar seas.