Name: North America's 3 Billion Lost Birds | SciShow News
Uploaded: 2019-10-28T02:05:12.000Z
Duration: 5 min 6 s
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thanks to things like habitat loss, climate change,

a study published in the journal Science,

by researchers from institutions across North America,

provided shocking evidence of just how bad things have gotten.

bird populations in the United States and Canada

Which works out to almost three billion birds

scientists used multiple bird monitoring survey datasets

they also used weather radar to track migrating species in flight,

who may not have shown up on the other ground-based surveys.

Although some species increased in abundance,

For example, those radar surveys indicated

a drop in the volume of migrating birds of around 14%

And grassland birds were particularly affected.

Their numbers have gone down by more than half since 1970,

and almost three quarters of grassland species are in decline.

And it's not because of really rare birds going extinct.

90% of the total loss in numbers happened in bird families that are pretty common,

including warblers, blackbirds and sparrows.

The study also outlined groups that have made a comeback,

like waterfowl, whose numbers have increased

who were helped by endangered species legislation.

The president of the National Audubon Society has called it a “full-blown crisis”.

See, the disappearing birds are an indicator

of the health of the environment in general.

North American ecosystems have been so affected by peopl

e that they can't support wildlife in the same way they used to.

but the authors suggest that habitat loss --

But human population growth could also be bad news for birds,

thanks to everything from pet cats to reflective windows.

And that's where we can do something about this bird crisis.

Some of the authors of the study also put out a list of things we can do on a personal

You can, for example, put stickers or screens on windows

Or plant more native trees and avoid pesticides

to make the outdoors a safe and inviting place for birdlife.

or even get a catio so they can experience the great outdoors

Whiskers might actually feel more comfortable when she's around you.

That's according to a study published this week in the journal Current Biology,

which found that cats actually form attachments to people

in a similar way to dogs and even human children.

Which contradicts cats' reputation for aloofness.

This study used a modified version of a classic psychological test

In that test, researchers look at how young subjects react

to a caregiver coming back after a short time away.

the young one's attachment instincts kick in

and that should offer some relief to the infant.

/But/ a young animal can't spend its whole time glued to Mom.

It also needs to explore and learn about the world.

That's where the secure base part comes in.

The caregiver offers a safe, comfortable point to come back to.

The test offers a way to stress young animals

and then see whether their stress is calmed by the caregiver's return.

Kittens who were securely attached to their human would greet them,

but then spend their time between their secure base and exploring their surroundings --

presumably checking in for chin scratchies once in a while.

Those that were insecure showed more signs they stayed/ stresse,

even after the caregiver came back, like licking their lips or twitching their tails.

70 could be classified using this technique.

were secure, which might explain why we think they're aloof

if they see us but aren't rubbing up against us as soon as we come home.

these attachments are pretty set once they form.

The researchers enrolled some of the kittens in socialization classes