Nesting Behaviour of Birds: Simple nest

This post of mine is continuation of nesting behaviour of birds.Simple nests or twig nests are built using plant material mainly twigs and sticks.The twigs are gathered on tree branches to build a simple platform just to support the eggs. Some nests have a depression on the middle but generally they don't have any inner or outer side.The eggs can be seen through the nest from below.common example of simple nests are those build by pigeons,doves, herons,Gulls and Eagles.

Nesting Behaviour of Birds: No Nest

The most simple form of nest is no nest at all.Many birds donot build any nest.They either lay eggs directly on the bare ground or rock surface. Some make simple scrap on the ground to lay eggs. It is observed that birds who leaves the nest soon after hatching, generally build this type of nest or more accurately they don't need complex nest at all.Nightjars lay their two eggs directly onto the ground.Birds like Plovers, Pratincoles, Lapwings, Little tern make simple scrap to lay eggs. As the eggs are on open surface they generally camoufladge with their surrounding and there by protected from predators. The picture above is a Little ringed Plover Nest with egg on open ground near a river bank.

Nesting Behaviour of Birds

Nesting Behavior of Birds

There is a common misconception that Birds build nests to live in it. It is not true. The fact is that birds build nest to lay eggs, raise their chicks, protect them from predators and adverse climate. Birds are notable for their instinct to build nest like humans and other animals. The nest varies from no nest (e.g Pratincoles) to very complex nest ( Baya weaver).

The nesting behavior of birds, the shape and size of nest varies according to their habitat, climate, breeding season, size and physiology of bird and amount of threat by predators. Broadly the nests can be divided into 12 categories.

1. No nest/ scrap nest

2. Simple twig nest

3. Cup nest

4. Cup nest with roof

5. Ball nest

6. Hanging / very complex nest

7. Mud nest

8. Hole nest in ground

9. Hole nest in tree

10. Floating nest

11. Edible nest

In my upcoming posts I will deal details about the individual nests.Birds are notable for their ability to build their nests most skillfully.

Sunbird, The Nesting

Nesting Season of Sunbird varies from February to June.Both the Purple and purple-rumped Sunbird has similar nesting behavior.I have discussed in detail how they build their nest in my post " Sunbird, The nest". The female generally lays 2 to 3 eggs of grayish color with brown spots.The female incubates the egg for a period of about two weeks.The young birds are fed by both the parents.The chicks feed almost 3 times more than their body weight.It is my personal observation that both the parent visit the nest almost 40 times in an hour to feed the chicks. Fledging period is almost 12 days.It is a great pleasure to watch the chicks coming out of the nest and jumping from branch to branch and the parents following them.

Purple Sunbird

Image via Wikipedia

Purple Sunbird
Species : Nectarinia asiatica
Family : Nectarinidae
Size : Smaller than sparrow

This is another species of Sunbird commonly found in Asiatic region.The only difference here is the color of the male. The breeding male is metallic black with a smooth shiny surface which ranges from green to purple . An orange patch is found on the armpit.Female are same are olive above and yellowish below. In both the species i.e purple sunbird and purple rumped sunbird the females look similar.For more information please read my post " The Purple Rumped Sunbird".

Sunbird, The Nest

Fig. The female Sunbird building the Nest

The nest of sunbirds are architectural marvel. It is generally suspended from a branch at a height of around 10ft from ground. It looks like an oval or oblong purse-shaped pouch with a hooded side-entrance.The collection of nest material and nest building are performed by the female alone with the male only accompanying the female.Before building the nest both male and female first select the appropriate branch of a tree.The female hover around it for a inspection and one can easily confused it with a humming bird. The nest materials consists of soft grasses, dry leaves, barks, pieces of paper and cobwebs.Cobwebs are generally used as a glue material. The nest is about 300 to 600 mm long from tail to tip.The diameter is around 50 to 70 mm at the broadest part.The outer layer consists of coarse materials like dried leaves, barks and even paper and polythene pieces.The inner layers consists of finer materials like cotton fibres or silky substances of seeds and flowers.The nest I observed mostly. The interior of the nest contains the egg chamber which is the thickest portion of the nest i.e 30mm thick.The interior gives utmost comfort to the chicks to grow.On a an average a nest is built with in 10 to 15 days.

Purple-rumped Sunbird

Fig. This is the female and male purple-rumped sunbird

Purple-rumped Sunbird

Species Nectarinia zeylonica

Family Nectarinidae

Size About 10 cm

Purple-rumped Sunbird is a colorful and very active tiny little bird.This bird is endemic to Indian subcontinent and a common resident breeder in India, Sri Lanka and Bangladesh. Purple-rumped Sunbirds are smaller in size i.e less than 10 cm long.The male and female looks different.The males have a dark metallic maroon upper side with a blue-green crown which glitter on sunlight. Metallic violet patches are also found around throat and only visible at certain angle.The female has a white throat followed by yellowish breast.The upper side is olive or brownish. They have medium-length thin down-curved bills and tubular tongues which are made for nectar feeding. This photograph is taken at Debrigarh wildlife sanctuary , Sambalpur, India.