Categories
Nature

Weaving for Love…

Southern or Masked Weaver male
Masked Weaver or Southern Weaver male. Photo by Sheldon_55 from Pixabay.

This brightly colored resident of Southern Africa has an incredible skill being able to weave a sturdy nest from strips of grass, bamboo or palm leaves. He goes through a whole routine to find a mate by firstly building the nest, which in itself takes around 15 hours. Then he does a whole lot of singing and fluffing his feathers around shaking them in a wings spread courtship display.

Eventually he will get a females attention and he will flutter around full of excitement, making an incredible fuss, often having to see off other would be suitors in the process. Each time he displays he moves closer to the nest he has built until eventually hanging from the entrance at the bottom of the nest and flapping his wings, all the time singing away.

Weaver nest display
weaver courtship display at base of nest showing entrance. Photo by Daniel Albany from Pixabay.

He then flies away from the nest opening, inviting her to inspect the house that he has built for her. This might take a while with multiple repeats to and from the nest at any point she may become bored with the whole charade and fly off leaving him to start searching for another female.

If he does manage to get her to inspect the nest, she will grasp the underside of the nest with her feet and then enter it from the opening near the base. She will disappear into the nest while he watches, ever hopeful…

If she thinks its good enough it remains as it is and they will start to prepare it by lining it with soft feathers in preparation for breeding…

However, if she doesn’t like it, nobody else will either !

She lets rip !

Tearing the whole thing apart before leaving him all alone and probably wondering what he did wrong!

Never the less, as the master of resilience, he starts again and builds yet another nest ( he may build up to 25 in a season) before trying to entice the next female. He may need to go through this process a number of times in a single season before being accepted.

Once successful and the kids have left home, he may start the whole process again having multiple broods in a season, each one with a different female.

These nests are typically built near water, often in the long dangling branches of the weeping willow tree, or a palm tree, other times in the reeds and even in suburban gardens.

Weaver nest built in reed bed
Weaver Nest built using reeds. Photo by Lynn Greyling from Pixabay.

As can be seen the nest built using reeds is pretty straight forward but the one hanging from a tree is sort of upside down with the entrance at the bottom. However, his design work has catered for the likelihood of the eggs rolling out by making the living area a little recessed from the entrance and a little bit lower.

So why build it like this in the first place?

The advantage of the entrance being below should be seen in conjunction with another feature. He has stripped off all growth on the branch that his nest is hanging on, but why?

The answer is snakes, by having no growth on the branch it makes it more difficult for a snake to access the nest, especially with the entrance below. Its not impossible, but rather difficult.

As a further defense, these little birds often create colonies and if a predator is in the vicinity they make an incredible noise and indulge in flying towards the predator in an intimidating manner.

After all of this the female will lay 2 beautiful blue eggs but could be up to 5 in number. Then it will take 12 days to hatch them. At this point the male helps with feeding the chicks and after 21 days they are ready to fledge. The main diet of these birds are insects, grain and even nectar, they readily accept picnic scraps and other hand outs.

Weaver eggs
Weaver eggs. Photo by Dennis Larsen from Pixabay.

Weavers are the only birds that are able to tie knots!

Categories
Nature

Elegance and Beauty

Asian Peacock
Peacock. Photo by Bishnu Sarangi from Pixabay.

The stunning peacock and National bird of India.

Lets start with getting the grammar right…

The male is the ‘peacock’, the female is a ‘peahen’, a group of these birds are referred to as either an ‘ostentation’, a ‘muster’ or a ‘party’. A group of females are called a ‘bevy’ and the babies are ‘pea-chicks’.

I had the good fortune to have a large piece of land and decided to buy some peafowl, one male and two females. I kept them in an aviary for a few days for them to get used to the place and realize that this was where the free food was…

After letting them out to range freely I noticed the male had disappeared. After about three days he returned, with two more females. To this day I don’t know where they came from or who owned them. Then he disappeared again and brought another female home. with breeding that summer, I soon had 14 birds. They really loved the tall trees on my property and I only seemed to gain birds.

A very good Turkish friend of mine explained to me what was happening – The male was creating a harem!

Another interesting fact that I learned was that one should not underestimate these birds ability to fly. I had the opportunity to see this skill in practice when watching a transfer of a new bird from a transport cage into an aviary when the peacock broke free and took to the air. It went high and far, very far – straight for some large trees close to the horizon and it didn’t stop on the way!

The birds I had to deal with were all of the Asian variety but there is also an African variety from the jungles of the Congo. First discovered in 1936 after an extensive search initiated after a feather was found.

African peafowl
Congo Peafowl. Photo by Wikipedia.

For this exercise we will focus on the more popular Asian varieties, being blue (from India and Sri Lanka) and green varieties (found from Myanmar (Burma) to Java). The male’s tail is referred to as a train and is regrown each year. As a defense against predators peafowl normally alight into the nearest tree. They are also very noisy birds, especially in mating season.

They nest on the ground, normally under a bush or thicket and lay up to 6 eggs but can be more. They hatch after about 28 to 30 days and the young are pretty independent in terms of feeding,being ground feeders.

Peahen with chicks
Peahen and peachicks. Photo by Mahnoor Qadri from Pixabay.

They will scratch around eating what they find, which will typically be plants, insects and anything else that opportunity presents such as amphibians or even scorpions.

I was always amazed at how the youngsters managed to get up into trees to roost with the parents at night, often encouraged by the mother with a clicking sound. Sometimes they didn’t quite make it to the top branch and one would find them arrayed on various branches below the mother.

It will take the pea-chick males another 3 years before they have a train like their father and they can expect to live for around 25 years. The albino variety of these birds are pure white and there are also some with a mix depending on their genetics.

White peacock
White peacock. Photo by Paul Brennan from Pixabay

The male is truly magnificent when attracting the female with his train erect and the ‘eyes’ of the feathers catching the sunlight especially when he shakes or rattles the tail giving a shimmering effect. This train is up to 60% of the bird but he loses all the tail feathers for winter and regrows them in the breeding season.

Peacock display
Peacock display to attract a mate. Photo by shajinnambiar2000 from Pixabay.

Around 2000 years ago the Romans raised peafowl both for the table and ornamental use but the Mesopotamian cultures had them 2000 years before that and the prior to that the Chinese kept them after importing them from India!

Categories
Nature

From Sprint to Stupor

Hummingbird in flight Photo by Domenic Hoffmann from Pixabay

This amazing bird is found in South and North America and migrates annually, flying a total of 1 300 miles (2 100 km)at a rate of 500 miles (800 km) a day. There are in the region of 320 to 340 species but lets dig a little deeper.

The beautiful hummingbird with all its agility and energy that enable its wings to beat at such a rate, being an average of 53 beats per minute but up to around 80. To support this activity requires blood flow and energy and in both of these areas this masterpiece has unexpected ability.

Wait for this ! The heart beats at over 1 263 beats per minute, given that humans in a healthy condition is around 60 to 70 its kind of WOW! there is another side though – it slows down on a cold night to between 80 to 150 beats a minute.

And what about energy usage when flying at high speed?

Hummingbirds move from flower to flower sipping up between 3 to 7 calories a day. Not much, right?

Actually in the context of the birds size its like a human having in excess of 150 000 calories a day!

Like that isn’t enough – we as humans consume glucose and fructose by eating fruit (there is also sucrose present but not our focus at this point).The human body uses the glucose for energy and converts the fructose into fat.

Our hummingbird, according to a Toronto university study is able to break down and use both glucose and fructose as energy making this birds metabolism quite incredible. this is quite unique and no other vertebrates can achieve this.

This allow our little friend to optimize energy use from 2 perspectives – firstly is can use the energy consumed really quickly and secondly, because it doesn’t have to do the human thing of converting to fat and storage, it doesn’t have excess weight to carry around which in itself demands more energy.

Another comparison from the Toronto Scarborough article – to fuel its flying speed, if our hummingbird was the same size as a human it would need one can of soda every minute!

There is more in nectar though – it also contains traces of proteins, salts, acids and essential oils and when our humingbird drinks, its tongue moves in and out at the rate of about 13 times a second .

Hummingbird feeding. Photo by dpexcel from Pixabay.

Pulling ourselves clear of the digestive system and we find that the hummingbird is also unique in that it is the only bird that can fly backwards.

They can also fly from side to side as well as the conventional up and down that most birds do. the difference to most birds is that the hummingbird has greater shoulder flexibility allowing a 180 degree movement with the tips of their wings tracing a figure of eight pattern. Simply by changing the angle of its wings this little marvel can change its direction in mid flight.

All the advantage is in the wings as these little fellow cannot walk or hop without using their wings and even then its not very effective. These little creatures are designed for a single role, nectar specialists. Their only leg function is to perch.

They can not smell but are very visionary, attracted by flower colors and surprisingly defend their territories, regularly attacking other birds such as Jays, Crows and even Hawks!

All hummingbirds are single mothers, once the mating has completed the male moves on. The females nest is made up of moss,lichens etc and binds it all up with spiderweb, making the little nest hard to find.

A hummingbird lays 2 eggs at a time and the egg size is smaller than a jelly bean. A chicken egg weighs in the region of 40 times as much as a humming birds egg. It takes between 15 to 18 days before it hatches.

Mom feeds the babies by inserting her beak into their mouths and regurgitating a nectar/bug mixture. After about 3 weeks the little ones are ready to fledge or leave the nest.

hummingbird reverse flight
Hummingbird revere flight. Photo by Francesco Bovolin from Pixabay.

During its night time tupor, the birds heart beat slows to 30 to 150 beats a minute and its temperature drops from 40 C to 18 C which conserves a lot of energy.

Categories
Nature

The Wandering Albatross

The graceful wandering albatross
The Graceful Albatross in flight. Photo by getspotted on pixabay.

The Royal Northern Albatross is the largest bird with a wingspan of more than 3 m (10 ft). These remarkable birds fly over the ocean foraging for up to 13 000 km (8 000 miles) in a single trip. They are estimated to travel in the region of 190 000 km a year (118 000 miles) !

Since the days of sailing ships sailors were amazed that the bird seemed unaffected by the weather and effortlessly flew for great distances. The even flew into the wind with what appeared to be little effort. The Albatross was most probably made famous by the poem “The Rime of the Ancient Mariner” by Samuel Taylor Coleridge and first published in 1798. The poem reflects the superstitious nature of the sailors of the day seeing the bird as a good omen. The story gets a little more complicated when the mariner shoots the bird and has to wear it around his neck as punishment.

The birds typically spend 5 years at sea and return to land when ready to breed. These amazing birds can live up to 60 years of age. There has been a study on the islands of Midway where the returning albatrosses collide with aircraft while soaring over the runways. The estimation is that around 34 000 bird have been killed but this has appeared not to have had much of an impact on their numbers. The suggestion made to reduce the problem was to flatten the ground for 750 ft (230 m)from the center of the runway which would reduce the air currents around the runways that the birds use.

So, what do the birds eat while at sea? and what about sleep?

Studies have shown that some birds prefer certain diets but generally they eat a mixture of foods such as squid, fish, crustaceans,krill, zooplankton and carrion. But who eats the albatross?

The albatross is predated on by the tiger shark but also other large predatory fish. This highlights their need to stay airborne rather than resting on the sea. Hence the belief is that they sleep on the wing but there are no studies as yet to support this.

Albatross taking off from the water
Black Browed Albatross taking off from the water. Photo by jmarti20 from Pixabay.

From a breeding perspective the oldest recorded female still laying eggs ad raising chicks was a Laysan Albatross and she was 63 years of age!

An albatross pair for life but are nevertheless promiscuous with a study that involved a mass paternity test that revealed just over 10 percent of young were not related to the father that was helping to raise them. The study also found that the males were equally promiscuous but the pair stayed committed to raising their chicks no matter who the father was.

Albatrosses form colonies usually on isolated islands, usually on headlands with good approaches to the sea. The birds are philopatric meaning they return to where they were born when they are ready to breed. Although birds have reached sexual maturity at 5 years they spend time in the colonies, often every year for a few years before actually breeding themselves. Incubation lasts around 70 to 80 days, making the albatross the record holder for the longest wingspan as well as being the longest incubation of any bird.

The chick is brooded for 3 weeks at which time it is able to defend itself and thermoregulate itself. From here on the parents feed the chick. The interesting point here is the parents alternate long and short foraging trips when feeding the young.

Albatross baby
Albatross chick. Photo by kklinzing from Pixabay.

How do the birds manage to stay in flight for so long?

Their technique is to find a skyward draft and to face into the wind. This gradually lifts the bird higher and higher until it is so high that feels the need to return to a lower point. It will then move out of the draft and glides back down to the ocean finding another upward draft and repeats the process.

The real incredible part is how the bird manages to navigate back to its breeding island and its flight techniques are instinctively there…