This Fly Torpedoes a Bindweed Bee’s Nest | Deep Look

A “bee fly” looks a bit like a bee, but it’s a freeloader that takes advantage of a bindweed turret bee’s hard work. The bees dig underground nests and fill them with pollen they collect in the form of stylish “pollen pants.” As the bees are toiling on their nests, the flies drop their *own* eggs into them. But the bees employ a tricky defense against the flies.

DEEP LOOK is an ultra-HD (4K) short video series created by KQED in San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.

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In the spring in California, male bindweed turret bees get into brawls with their peers as they search for a female to mate with. Males pile onto each other and form so-called “mating balls,” an inaccurate name, since no mating is occurring. Rather, the males are getting into fights. The female they’re vying for is caught at the bottom, and sometimes the battle is so intense the males accidentally kill her. But, if she survives, she and the male who won steal away and mate.

Once they’ve mated, females dig through compacted dirt to make a nest underground, where they’ll lay their eggs. The majority of the world’s bee species – 70 percent – are ground-nesting. The bindweed turret bees in this video chose a dirt parking lot near the town of Winters, in the Central Valley. These native bees are known by the scientific name Diadasia bituberculata.

Females tirelessly scoop earth with their mandibles, softening it by dousing it with nectar they collected earlier. They work side by side, but each is “queen” of her own castle.

As they dig out their nest, they often build a turret at the entrance. These dirt towers usually aren’t vertical: Many of them are tunnel-like, with a sideways entrance. Others curve down. With their entrances facing away from the sky, the turrets protect the bees’ nests when bee flies start dropping their eggs from the air.

--- What is another name for a bee fly?
Bee fly is the common name for the more than 4,000 species of flies in the family Bombyliidae.

--- How do bee flies parasitize bees?
The Paravilla fulvicoma bee flies in our video drop their eggs into the nests of bindweed turret bees. When the fly’s egg hatches into a larva, it digs tiny hooks into a bee larva. But the bee larva doesn’t die. It grows by feeding on the pollen that its mother packed for it inside the nest. As the bee larva grows, the fly larva sucks it dry and kills it. Then the fly finishes growing into an adult and pushes up through the ground to emerge the following spring.

--- How do you tell a bee fly from a bee?
Even though bee flies have hairy bodies like bees, if you look closely, you can tell them apart. Bee flies have big eyes that cover a large area of their heads. And bee flies’ antennae are short compared to bees’ antennae.

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#beeflies #nativebees #deeplook

[eaterofcrayons]

The way they wiggle and shuffle or ploop their way into their tiny tube homes with a bumfull of pollen is unexpectedly adorable

[dukethespider]

The buzzes they make while digging are so cute.
The pollen pants are beautiful.

[xerolith]

Those shots of the pollen pants just sliding down the tunnels was hilarious. Well done!

[manbeard]

2:25 they are so cute when they crawl to their nests.

[OptimusPrime-odzh]

Nature is odd weird and amazing all at the same time

[bonk]

This channel truly deserves much more recognition than it has, the amount of information and clear footage is marvelous

[yamihikarilightdark]

The music is my favorite part. It’s the icing on the cake seeing lil wiggly bee bums with pollen pants. :)

[thomaslai]

2:00 And not a few days ago, I was walking around Aberdeen, and seeing bindweed flowers thought to myself, “surely, these are morning glories!”

Thanks for the clarification, Deep Look!

[momoooring]

I'm just here for the "Pollen Pants" ;_; so freaking cute!

[EmperorHelix]

Hey Deep Look, request to know if you'll make a segment on the Spotted Lanternfly? They're an invasive menace in the northeast and your channel is perfect to help bring awareness and educate us on this insect. Thank you!

Edit: typo correction

[suyci]

The camera work is nothing short of amazing. Great job!

[pencilsniper]

2:21 the little teenie tiny feet sticking out 😆😂

[BlackRedsBumblebeeWasp]

0:57 Aww, so cute!! What a beauty, keep it up!!!

[zezekingyo]

Forget this. If I were a zoologist, I would've called that the "Cuckoo fly" for reference

[frankeneh-lffb]

I thought bee flies only attacked tree bee nests not ground bee nests!

But why is betrayal EVERYWHERE when you're SMALL?

[blablableh]

Props to the ppl who helped protect the bees, good Karma and noted.

[alpacaofthemountain]

Nature can be both horrifying and adorable at the same time

[Deas-Mhumhna]

Unfortunately, bindweed in Colorado is aggressively invasive. Choking out native plants and wrapping around structures. We are told and tasked to remove any we find. Luckily we found an insects that eats bindweed so the numbers in our native areas should be dropping into a controlled population.

[DJwizz]

Man the male bees are on the next level of thirsty lol

[caottico]

Hey everyone, thanks for tuning in to another fantastic video! I'm always impressed by the clever and captivating content in these videos. The way the text is presented adds an extra layer of interest, and I can't get enough of how enchanting these little creatures look through a macro lens.