Nature and Life - Episode 228 (Breeding of Colonial Birds)

Описание: Reproduction process is vital for every living organism.
Because organisms survive from generation to generation through reproduction.
But there are variations in the breeding process of different species.
Birds are occupying a major portion of the animal kingdom.
They generally breed after building their nests.
Though most of the birds make their nests individually, some complete their breeding after making their colonial nests.
Such colonial breeding is their inherent behavior.
Among these birds, there are various species of Herons, Cormorant, Asian Openbill, Adjutant, Weavers etc.
Different species of Herons are seen in Bangladesh.
They have diverse physical structure, color and behavior.
But they go through different physical changes during breeding season.
The changes in color occur for attracting their mates.
Though they roam alone, in pair or in small herds, they unite together in a group during breeding season.
Numerous birds make colony to build their nest together.
Sometimes the members of the same bird species make their nests in a colony.
And sometimes they make their colonial nests with other species too.
Usually different Cormorant species join together with the Herons.
Together they make their colony to complete breeding at the same time.
Sometimes they nest on a single tree, sometimes on several trees.
Their breeding colonies are seen at different places in Bangladesh.
They usually complete their breeding at the end of the rainy season.
They mostly build their nests on the large trees beside the wetlands.
They select the large trees beside the wetlands to easily feed their new born chicks.
In some colonies hundreds of birds are seen to build their nests.
Sometimes they share the same colony for roosting or nesting.
After hatching the chicks, the parents get busy with collecting food.
They bring their food from far away and feed their own chicks.
They spend most of the day time in search of food.
The birds return to the colony just after the dusk and take rest.
These birds generally use the same colony for many years.
The Asian Openbill is a large bird in Bangladesh.
They also build their nests in a colony like the Herons.
The male and female birds make the colony together.
Sometimes they build large nest in other birds’ colony.
They usually don’t breed until they find a safe breeding ground.
Lesser Adjutant is also a colonial bird.
Their population has decreased due to lack of food and tall trees.
They are found in the Sundarbans and some places in the northern regions of Bangladesh.
They build their nest on the top of the trees in breeding season.
Both the male and female take part in building their nest.
Their nest is quite large.
Both the male and female feed their chicks after hatching.
The chicks learn to fly after 30-35 days.
The Weaver bird also breeds in colony.
The nests of the Weaver birds are still found on the palm, coconut or date palm trees beside the country roads.
They build their hut like hanging nests with slender leaves.
They are famous for their striking nests.
The Bee-eaters also breed in colony like them.
Their breeding process is different.
Numerous Bee-eaters breed after building nests in the earthen holes.
Numerous birds are surviving in this world through their colonial breeding.
These birds are the friends of the nature.
They keep the earth beautiful and running.
But due to various reasons their colonial breeding is being hampered.
Their reproduction is being disturbed due to deforestation, people’s unawareness and lack of food.
So the population of the colonial birds is gradually decreasing.
Some species are now at the brink of extinction.
So our ecosystem is being imbalanced.
So, the appertaining authorities have to come forward to conserve the colonies of birds.
General people also have to play role in conserving these colonies.
Only then these birds will sustain in the nature of Bangladesh.