Date: Oct 05, 2020
Title: All About Hummingbirds no captions
Speaker 1 - 00:00:00 > 00:00:04 Ruby-throated hummingbirds are considered
a small hummingbird species.
Speaker 1 - 00:00:05 > 00:00:14 Their average weight is anywhere from about
3 grams to about 3.4 grams, which is about the weight of a nickel in your hand.
Speaker 1 - 00:00:15 > 00:00:19 They're 3.5 inches from the tip of their tail
to the tip of their bill.
Speaker 1 - 00:00:20 > 00:00:23 Females and young birds are slightly bigger
than males.
Speaker 1 - 00:00:23 > 00:00:27 They beat their wings in a figure eight motion
Speaker 1 - 00:00:27 > 00:00:29 60 to 80 times a second.
Speaker 1 - 00:00:31 > 00:00:34 Hummingbirds can fly upwards of 40 mph.
Speaker 1 - 00:00:35 > 00:00:39 Flight muscles make up 25% of their body mass
Speaker 1 - 00:00:40 > 00:00:46 In relation to their body size, hummingbirds
brains are one of the biggest in the avian world.
Speaker 1 - 00:00:47 > 00:00:48 So they're pretty smart birds.
Speaker 1 - 00:00:50 > 00:00:57 Their hearts beat 250 times a minute at rest,
up to 1,200 times a minute in flight.
Speaker 1 - 00:00:57 > 00:01:05 All hummingbirds are characterized by those
iridescent feathers, most especially the males.
Speaker 1 - 00:01:05 > 00:01:08 They have 945 feathers
Speaker 1 - 00:01:09 > 00:01:18 and they will molt those or lose them, each
one, in a systematic and symmetrical way every year and that process is called molt.
Speaker 1 - 00:01:19 > 00:01:31 The brilliant iridescent colors of hummingbird
plumage are caused by a refraction of light through flattened particles in the feather
called platelets.
Speaker 1 - 00:01:31 > 00:01:42 Each of these contain mulls that act like
tiny prisms that break the white light into component colors before reflecting it back
out of the feather.
Speaker 1 - 00:01:42 > 00:01:47 So think of a rainbow, it sort of works the
same sort of way.
Speaker 1 - 00:01:49 > 00:01:54 Ruby-throated hummingbirds bill is soft and
it's easily damaged.
Speaker 1 - 00:01:55 > 00:01:56 It's flexible.
Speaker 1 - 00:01:56 > 00:02:01 It has a rich blood supply and it's very sensitive
to the touch, so you can think of their bill
Speaker 1 - 00:02:02 > 00:02:04 like the tips of your fingers.
Speaker 1 - 00:02:05 > 00:02:10 The bill is also there to help protect the
tongue because the tongue is highly specialized.
Speaker 1 - 00:02:11 > 00:02:13 Their tongues have two grooves at the end
Speaker 1 - 00:02:14 > 00:02:15 and it's forked.
Speaker 1 - 00:02:18 > 00:02:26 Their tongues also look like hollow tubes
and it was long thought that they use their tongue like straws,
Speaker 1 - 00:02:26 > 00:02:32 but in a 2015 study, with a very slow motion
camera.
Speaker 1 - 00:02:33 > 00:02:37 It was revealed that their tongues actually
act like a micro pump.
Speaker 1 - 00:02:38 > 00:02:47 So a Hummer will approach a food source, and
it squeezes his tongue flat compressing it and building up potential energy.
Speaker 1 - 00:02:48 > 00:02:50 Then the tongue hits the nectar
Speaker 1 - 00:02:50 > 00:02:54 the groove spring open to their original tube
like form
Speaker 1 - 00:02:55 > 00:02:58 acting like a pump and sucking that nectar
in
Speaker 1 - 00:02:59 > 00:03:01 and so that they can feed.
Speaker 1 - 00:03:01 > 00:03:06 This all happens 15 to 20 times per second
Speaker 1 - 00:03:06 > 00:03:08 and it happens all day long.
Speaker 1 - 00:03:08 > 00:03:11 As hummingbirds need to eat about every 15
minutes.
Speaker 1 - 00:03:11 > 00:03:14 When it comes to reproduction.
Speaker 1 - 00:03:14 > 00:03:17 The female Ruby-throat is the workhorse of
the pair.
Speaker 1 - 00:03:18 > 00:03:24 Males only job is to defend a territory and
breed with as many females as possible.
Speaker 1 - 00:03:24 > 00:03:26 It's the female who does all the work.
Speaker 1 - 00:03:26 > 00:03:31 She builds the nest, and feeds and raises
the babies.
Speaker 1 - 00:03:32 > 00:03:36 Ruby-throated hummingbirds are currently the
only species known to breed east of the Mississippi.
Speaker 1 - 00:03:38 > 00:03:42 Hummingbird nests are about the size of a
English Walnut.
Speaker 1 - 00:03:43 > 00:03:49 They are made of spider webs, covered in lichen,
and filled with soft fibrous materials.
Speaker 1 - 00:03:50 > 00:03:56 They're unique in that they will expand as
the babies grow because of the spider webbing.
Speaker 1 - 00:03:56 > 00:04:00 The nests are usually found on a downward
branch at the bottom of
Speaker 1 - 00:04:01 > 00:04:06 the canopy, sometimes over water, anywhere
from 8 to 60 feet high.
Speaker 1 - 00:04:07 > 00:04:12 As I said all the work of building the nest
and raising the young is done by the females.
Speaker 1 - 00:04:13 > 00:04:24 Hummingbirds will reuse nests if they were
successful in fledging young from that nest the following year.
Speaker 1 - 00:04:24 > 00:04:31 We also know from studies, that while they
are feeding young in one nest in Tennessee,
Speaker 1 - 00:04:31 > 00:04:34 they are usually building a second one and
getting ready for a second brood.
Speaker 1 - 00:04:35 > 00:04:41 The female Ruby-throat lays two eggs and only
two eggs two days apart.
Speaker 1 - 00:04:41 > 00:04:45 The eggs are about the size of a Tic Tac or
a Black-eyed Pea
Speaker 1 - 00:04:46 > 00:04:56 and unlike other songbirds which lay a whole
clutch of eggs and then begin to incubate ruby-throated hummingbirds begin incubation
as soon as the first egg is laid.
Speaker 1 - 00:04:58 > 00:05:09 So that means that 1 egg will hatch two days
before the other so one bird will always be bigger than the other until they eventually
catch up with each other.
Speaker 1 - 00:05:10 > 00:05:15 She will incubate those eggs for 12 to 16
days
Speaker 1 - 00:05:16 > 00:05:22 sitting on that nest 80% of the day, only
leaving to feed herself and then returning.
Speaker 1 - 00:05:23 > 00:05:29 When the babies hatch after 12 or 16 days,
they're the size of about a bumblebee.
Speaker 1 - 00:05:30 > 00:05:33 They'll double their size and their weight
very quickly
Speaker 1 - 00:05:35 > 00:05:42 and when they're born,they have no feathers
and they're blind
Speaker 1 - 00:05:42 > 00:05:44 but their mother takes very good care of them.
Speaker 1 - 00:05:45 > 00:05:49 She feeds them a slurry that she makes in
her crop
Speaker 1 - 00:05:50 > 00:05:58 of insects for protein, and nectar for carbohydrates,
and it's that slurry that enables these babies to grow.