0:00

Today in Science from Wired. When

0:30

you need mealtime inspiration, it's worth shopping Kroger. No

0:45

matter what tasty choice you make, you'll enjoy

0:47

our everyday low prices. Plus, extra ways to

0:49

save, like digital coupons worth over $600 each

0:51

week. You can

0:53

also save up to $1 off per gallon at

0:55

the pump with fuel points. More

0:57

savings and more inspiring flavors. Kroger,

1:03

fresh for everyone. Fuel restriction

1:05

supply. Today, how a

1:07

Firefly course is saving Japan's favorite glowing

1:09

insect. The fireflies of Moriyama

1:11

City have long been prized and

1:14

hunted for their yellow-green glow. To

1:16

bring populations back up, amateur

1:18

conservationists are hitting the books. At

1:22

the third meeting of the Moriyama City

1:24

Firefly Forest Museum's 8-week Firefly course, a

1:27

conservation training program for adults, egg

1:29

collection begins. Each female

1:31

Genji Firefly, Nipunoluciana cruciata,

1:34

can lay up to 500

1:36

of the caviar-like orbs, carefully

1:38

depositing them across the mossy banks of

1:41

rivers and streams in blankets of pale

1:43

yellow. In the wild,

1:45

only a tiny fraction of the eggs survive.

1:48

River pollution, flood prevention measures,

1:50

overfishing, and excess urban light

1:52

devastated the insect's population in

1:54

the 20th century. But

1:56

at the museum, artificial breeding and rearing methods

1:58

will coax the eggs. 30,000

2:01

Genji Fireflies into larva, a

2:03

phase in which they live like

2:05

tiny, voracious underwater explorers. Each

2:08

month, the 10 students of the

2:10

Firefly Course return to the museum

2:12

to learn about the breeding and

2:14

rearing techniques of the Genji and

2:16

their primary food source, freshwater snails,

2:18

thierody. "'Hundreds of thousands

2:21

of water snails are required to

2:23

feed the larva,' explains Firefly Forest

2:25

Museum director and Firefly Course teacher

2:28

Michio Furukawa. They'll help

2:30

the fireflies multiply up to 20 times

2:32

between birth and maturity, growing in length

2:34

from the thickness of a grain of

2:36

rice to the diameter of a penny.

2:39

By the student's seventh meeting, about 5,000 of

2:42

the hatchlings will have survived long enough

2:44

to be released from their breeding tanks

2:46

into the museum's man-made river in February.

2:49

Only the hardiest of the bunch will reach the

2:51

final stage of adulthood, the one that glows. 30

2:54

years ago, when the Moriyama City

2:56

Firefly Forest Museum first opened, the

2:59

future looked dark for the revered

3:01

Genji Firefly, whose populations had barely

3:03

begun to recover more than six

3:05

decades after Japanese conservationists recognized that

3:07

their lights were going out. It

3:10

wasn't always this way, especially in

3:12

Moriyama, where swift rivers and pristine

3:14

natural banks made for the ideal

3:16

Genji habitat. In Japan,

3:19

fireflies have long been the harbingers of

3:21

summer, taking to the skies in June

3:23

and July in a flickering dance of

3:25

courtship that lights up the night. Moriyama's

3:28

Genjis were especially prized for

3:30

their vivid yellow-green glow, drawing

3:32

tourists from around the country by at

3:35

least the mid-19th century. But

3:37

eventually, intrepid entrepreneurs realized that they

3:39

could make money by capturing and

3:41

shipping the tiny insects from Moriyama

3:43

to population centers like Osaka, Kyoto,

3:45

and Tokyo than they could by

3:47

waiting for urbanites to come to

3:49

them. Throughout Japan's Meiji period,

3:51

which stretched from 1868 to 1912, a

3:55

commercial firefly industry gorged on the

3:58

colonies emerging from Moriyama's waterways. In

4:00

just one night, a single firefly hunter could capture as

4:02

many as 3,000 of their prey, scraping

4:06

the earth with bamboo brushes to

4:08

frighten just-mated egg-laying genji from the

4:10

riverbeds. The next morning, the

4:12

insects were carefully packaged and shipped off

4:14

to form the luminous blinking decor at

4:16

fancy hotels, restaurants, and private gardens. This

4:20

episode is brought to you by Delete.me. Hey

4:22

guys, Zeke Robinson here from the wired.com

4:24

podcast. And if the podcast has taught

4:27

us anything, it's that cybercriminals are out

4:29

there, and they're clever, and

4:31

they are relentless. And as

4:34

technology and AI get bigger and

4:36

faster and smarter, so are the

4:38

cybercriminals. All they need is a

4:40

few tidbits of your personal information, and they can

4:42

send you phishing emails, they can get at your

4:44

bank accounts, they can open accounts in your name,

4:47

steal your identity, they can even use the information

4:49

to stalk you or dox you. So

4:51

to take steps to protect myself, I chose

4:54

Delete.me. Delete.me is a subscription

4:56

service that removes your personal information from the

4:58

largest people search databases on the web. You

5:00

sign up, you log in, you fill out

5:02

what they call a data sheet, which is

5:04

eight crazy simple steps for me. You hit

5:06

the submit button, and they're opposed to take

5:08

it from there. So take control of your

5:10

data and keep your private life private by

5:12

signing up for Delete.me. Now at a special

5:14

discount for our listeners, get 20% off

5:17

your Delete.me plan when you

5:19

go to join delete.me.com/wired and

5:21

use promo code WIRED at checkout.

5:24

The only way to get 20% off is

5:26

to go to join delete.me.com/wired

5:28

and enter code WIRED at

5:30

checkout. That's join

5:33

delete.me.com/wired code WIRED.

5:37

For years, it was Moriyama's fireflies that

5:39

had the honor of being presented to

5:42

Emperor Meiji as a precious gift, which,

5:44

in Japanese culture, symbolizes passion and the

5:46

fleeting impermanence of all living things. Harvesting

5:50

fireflies was a big business, says

5:52

Tufts University biologist and firefly researcher

5:54

Sarah Lewis, author of Silent Sparks,

5:57

The Wondrous World of Fireflies. It

5:59

was all also a death sentence, not

6:02

just for those fireflies which, when released

6:04

in cities or kept in lanterns or

6:06

cages there, had no appropriate habitat

6:08

to lay eggs or grow into larva,

6:10

but for the firefly ecosystem back home.

6:14

Because it was easiest to capture female

6:16

Genji as they laid their eggs on

6:18

the mossy riverbank, she explains, there were

6:20

fewer and fewer left to produce the

6:22

next generation. Meanwhile a

6:24

fast urbanizing Japan was turning

6:26

Moriyama's once ideal Genji habitat

6:28

into a toxic, pesticide-spiked morass

6:30

in which few fireflies could

6:32

survive. Concrete was laid

6:35

on the banks where there was once

6:37

moss to protect their eggs, wastewater and

6:39

industrial runoff seeped into the clear waters

6:41

where the larva grew, overfishing

6:43

disturbed the juvenile insects and their snail

6:45

food source. More than

6:47

a century later, Moriyama's firefly population is

6:50

rebounded only slightly from its near extinction

6:52

in the first half of the 20th

6:54

century. When it was established

6:56

in 1990, the Firefly

6:58

Forest Museum's founders set its

7:00

rustic, wood-clad institution in the

7:02

kind of habitat Genjis would

7:04

find irresistible. They dug

7:07

a fast-moving artificial stream and planted

7:09

its banks with soft, protective moss.

7:12

They brought in trees from the nearby

7:14

Yasu River, planting them in a shady

7:16

grove without lights that might confuse the

7:18

amorous bugs during mating season. Inside

7:21

the museum they mated and bred the Genjis.

7:23

It is still the only public institution to

7:25

do so on a large scale according to

7:27

Furukawa. Today the process

7:29

begins in the fall with moss-layered

7:32

trays in which, flashing male and

7:34

female fireflies, a signal of their

7:36

sexual receptivity, generate thousands of fertilized

7:38

eggs. When they hatch,

7:40

the larva are transferred from the moss to

7:42

tanks filled with artificially flowing spring water. They

7:45

grow there in a gluttonous orgy of

7:47

snail consumption until February, when the larva

7:49

are hardy enough to move to the

7:52

man-made Firefly River, joining their naturally bred

7:54

cousins for the remaining months of snail-noshing.

7:57

Then, together, the fireflies leave the water and

8:00

take flight beginning in June. The

8:02

sciences sound, but despite their efforts, the

8:05

number of Genji fireflies has not increased

8:07

so much in the region, says Furukawa.

8:10

Habitats continue to decrease due to urbanization,

8:12

and Moriyama City is constantly debating what

8:14

to do in the future. Unless

8:17

they preserve existing habitat and create

8:19

new spaces for the insects, fireflies

8:21

will continue to suffer. No

8:23

matter how many fireflies the museum and

8:26

its acolytes are able to produce in

8:28

the artificial firefly forest, those

8:30

that survive into the next generation

8:32

have no need to move beyond

8:34

the optimized habitats into dirtier, more

8:36

urbanized natural environments. That's a

8:38

major problem for actually restoring their

8:41

populations. Sometimes people try

8:43

to increase only the fireflies and

8:45

forget to conserve the whole habitat,

8:47

says Yuichi Oba, an environmental biologist

8:49

who studies fireflies at Chubu University

8:52

in Kasuga, Japan. They

8:54

can release the cultured larva to the river,

8:56

but if the river is still dirty, of

8:58

course the larva cannot survive. That's

9:01

where the museum's educational objectives come in.

9:03

Throughout the year, Furukawa lectures on the

9:05

revered insects' history and ecology in elementary

9:07

and high schools. The museum

9:09

also offers educational resources such as

9:12

the eight-week firefly course for adults

9:14

and other training and awareness campaigns,

9:16

including the museum's magazine, From the

9:18

Firefly Forest. Though they've

9:21

been slow to pan out, similar efforts are

9:23

happening elsewhere. The Okazaki City

9:25

Firefly School, in addition to educating

9:27

local children and families, organizes community

9:29

cleanup efforts in and around the

9:32

Odagawa River. These efforts may

9:34

make a difference in the long

9:36

run, explains Daichiro Kato, a firefly

9:38

researcher at Kagoshima University in Kagoshima,

9:40

Japan. I believe

9:42

that if the general public becomes more

9:45

interested in and engages in conservation activities

9:47

nationwide over the next 10 to 20

9:49

years, the local environment will

9:51

be restored little by little and may

9:53

contribute to the long-term recovery of the

9:55

firefly population. But for Genji

9:58

firefly populations to have a chance,