Swarms of dragonflies have been filling the skies in California, with onlookers spotting hundreds of the creatures overhead and even witnessing them mate on top of people’s hats.
The insects have reportedly taken over parks, grassy areas, ponds and rivers throughout the Bay Area as they hunt for food during a pivotal phrase in their life cycle.
From June through August, entomologists called the summer months in the US ‘peak dragonfly season,’ meaning these large flying bugs are emerging from underwater breeding grounds and becoming common sights around local lawns and meadows.
Squadrons have been seen flying over grassy hills near Lake Merritt in Oakland, along the Russian River near Guerneville and gathering around new plants in San Francisco’s Dolores Park.
One person in the Bay Area said: ‘I never ever used to see dragonflies. Since the last maybe year or year and a half there are SO MANY all over the city.’
While a giant swarm of flying insects can be unnerving, these swarms can actually be a positive for the West Coast, as the dragonflies are actively hunting their main source of food – mosquitoes.
Chris Grinter, senior collection manager of entomology at the California Academy of Sciences, told SFGATE: ‘Cool weather, wind currents, and an abundance of food (mosquitoes) are likely contributing to the high numbers.’
Adult dragonflies can kill up to 100 mosquitoes in a single day, while their larvae act like underwater predators which kill and eat mosquito larvae in their breeding grounds – such as pools of standing water throughout the populated urban area.
A close-up of a dragonfly landing on a plant (Stock Image)
Pictured: A dragonfly swarm seen on a beach in Rhode Island in 2024
Dragonfly season is not confined to just California. Newly hatched and grown insects are emerging from their ponds and lakes across the US.
Massive dragonfly swarms were seen blitzing past beachgoers in Rhode Island in July 2024 as they migrated to warmer breeding grounds along the East Coast.
The creatures are able to survive longer in the South and near the West Coast, which typically sees the climate stay hotter as summer turns to autumn.
Dragonflies start laying eggs near the start of summer, sometimes as early as April, right after the adults emerge from the water, mature and mate.
They deposit their eggs in or near water, or into plants or mud along local water sources.
The eggs usually hatch within days or weeks, with the nymphs growing underwater throughout the cooler months.
The next generation of dragonflies emerge as full-size adults the following spring and summer.
The busiest time to see flying adult dragonflies is June through August, with their numbers often at their highest now as they going hunting for local pests to eat. They also eat gnats and other types of flies, making them natural insect repellents for people.
Dragonfly swarms are emerging from water sources as fully grown insects searching out mosquitoes for food (Stock Image)
In the Bay Area, where the swarms are growing now, researchers say there are around 30 different species of dragonflies in the region.
They can fly up to 35 mph, grow up to five inches in length and have wingspans over around six inches.
That makes them look like flying ballpoint pens with wings the same length as your average smartphone.
Luckily, dragonflies are harmless to humans.
They have no stingers, do not carry venom and do not see humans as food.
Another California resident on social media claimed: ‘It’s the entire region. Washington Square Park has millions right now. Thousands by the Ferry Building this morning. Tons at Golden Gate Park yesterday.’
