Summer is here in Sydney (but so are the stingers)

As Sydneysiders flock to the coast in anticipation of the warmest day since March, an armada of blue boots washed up on the state’s beaches from the Entrance to Thirroul, riding in warm north-easterly winds.

Kevin Crick, president of the Woonona Surf Life Saving Club on the south coast, said he was used to seeing blueboots “appearing out of nowhere” but the timing of their arrival this week was strange.

“We don’t usually catch them this early,” Crick said, “They’re prolific, they always show up, it’s just unusual to have so many people here this early.”

A mass arrival, or “bloom,” of blueboots—sort of stinging warships—occurs every summer when favorable weather and reproductive conditions coincide, with the last major event occurring in 2021. During the week, the midday shift on Saturday brought north-easterly winds that were favorable for blueboots hitting Sydney beaches.

Bluebottles have been spotted on a number of beaches along Sydney’s coastline, and swimmer warnings are being issued at Wylie’s Baths and McIver’s Ladies Baths ocean pools.

The bloom comes as a high of 32 degrees is expected in Sydney on Sunday, with a “very high” UV index of nine. Jake Phillips, a meteorologist at the Bureau of Meteorology, said the forecast showed a “fairly warm week overall” with temperatures falling slightly before returning to the 30s on Wednesday and Thursday.

“The long-term average (for this time of year) is 23.7 degrees. If we reach the projected maximum, we will be well above average, but not in record territory.”

What is a blue bottle and how does it sting?