Posts Tagged 'maharashtra'

baya weavers nesting

Posted by on 04 Sep 2016 | Category: photography, prakriti

It is nesting season for the baya weavers!

Baya weaver birds are small, sparrow-size birds which resemble the sparrows during the non-breeding season. During May-June, as the breeding season approaches, their gonads (sexual glands) become active and the adult males develop yellow and black color plumage on head, breast and throat; and their bills also darken. By the time the monsoon starts, the males are in bright yellow summer colors, and ready for breeding through the monsoon season (June-September).

baya weaver nest building

Why do they breed during the summer monsoon? Obviously, the grass is green during this side of the monsoon! Baya weavers forage in flocks for seeds on wild grass like these below, which are plenty after the monsoon rains. This is also the time when insects are plenty, especially to feed their young. How many bayas can you count in the image below?!

a group of baya weaver birds feeding on grass seeds

Nesting success? Baya weaver nests are exclusively built by the males and then displayed to the females. What are the factors on which the female makes it selection? Among birds, elaborate nests and decorations built by males may help females to assess a male’s quality. One of the most popular architectural attributes of the weaver nest is the entrance tube, which can get as long as 90 cm. Female birds are also selective in choosing nests which provides safety (in terms of nest height and location). So what does the baya weaver base their selection on? Is it the architecture or the location?

baya weaver nest building at Pune, Maharashtra

Safer on thorny trees: Observation shows that the female weavers are inclined towards nests which are safely located in thorny trees, farther away from the trunk and situated high above the ground. Thornless trees have higher rates of snake predation than thorny trees. Nesting success also increases with with thickness of the supporting branch and for nests which are woven with fine fiber.  Thick branches may stabilize nests during strong monsoon winds, and may also be less likely to break.

baya weaver and a garden lizard against the blue sky

Despite these precautions, garden lizards like the one above, and tree mouse do occasionally raid these nests.

Some history: Baya weavers and their unique nesting nature were first recorded in Ain-i-Akbari, the 16th-century document recording the administration of Akbar’s empire, and which is part of the a much larger document, the Akbarnama. The Volume III translation by Colonel H. S. Jarret talks about wild/domesticated bayas: “The baya is like a wild sparrow but yellow. It is extremely intelligent, obedient and docile. It will take small coins from the hand and bring them to its master, and will come to a call from a long distance. Its nests are so ingeniously constructed as to defy the rivalry of clever artificers.”

Species: Ploceus philippinus
English: Baya weaver
Location: IITM colony, Pune, Maharashtra
Date: 3 Sep 2016

References:
1. Balasubramanian, K. S., & Saxena, R. N. (1973). Effect of pinealectomy and photoperiodism in the reproduction of Indian weaver birds, Ploceus philippinus. Journal of Experimental Zoology, 185(3), 333-340.
2. Fazl, A., & Jarrett, H. S. (1983). The Ain-i-Akbari:. Royal Asiatic Society of Bengal. (No. 61).

3. Quader, S. (2006). What makes a good nest? Benefits of nest choice to female Baya Weavers (Ploceus philippinus). The Auk, 123(2), 475-486.

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Indian Grey Hornbill—the seed dispersers

Posted by on 07 Aug 2016 | Category: photography, prakriti

There are about 54 species of hornbills in the world, out of which 9 occur in India. The hornbill pictured here is the Indian Grey Hornbill, which is common across the Indian subcontinent, except the wettest (Western Ghats and northeast) and the driest (northwest) parts of the country.

Indian Grey Hornbill, Ocyceros birostris at Pune, Maharashtra

Breeding/Nesting
Hornbills have unique breeding habits, where the female confines herself into a nest cavity in a tree, with only a narrow opening through which the male shares the food throughout the nesting period. For the Indian grey hornbills, the total nesting period is about 87 days, where the female is confined to the nest cavity for an average of 76 days. Most of the grey hornbill nests are in hollows of the Mahagony tree family, located nearby riverine habitats. Deforestation, agriculture and other developmental activities have restricted the range of many species like these hornbills.

Grey hornbills as seed dispersers
Hornbills play a key role in seed dissemination, germination and regeneration of trees. This is because they are mainly frugivores (fruit consuming) and can break up/swallow large fruits, and regurgitate the seeds without damaging, making them the perfect dispersers. Since they travel long distances in search of fruits, they are capable of moving these seeds to distant locations.

Grey hornbills are effective seed dispersers for trees such as Premna tomentosa (a teak like tree), Putranjiva, Fern trees and even Sandalwood trees! Many of these are medicinally and commercially valuable trees but they generate very few seeds and propagation depends on birds like these hornbills.

Mid-air play and fight
Like many other hornbills, the grey hornbill has a long curved bill, which has a casque (helmet) on the top. The male hornbills engage in midair clashes where they jar against each other’s casques to establish their dominance and as part of their social play. This behaviour is known as aerial jousting.

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olive ridley turtles—and dinosaurs

Posted by on 27 Mar 2016 | Category: prakriti

Watching these Olive Ridley turtle hatchlings making their first steps to the sea is an emotional experience!

Olive Ridley Turtle hatchling, Velas, Maharashtra

Olive Ridley turtles are among the five species of marine turtles which are known to inhabit Indian coastal waters and islands. Odisha on the eastern coast of India hosts one of the largest mass nestings (known as arribadas) of these turtles, supporting a nesting population of probably more than half a million.

There are Olive Ridley turtle populations elsewhere in the Indian Ocean too, scattered around from Sri Lanka to Kerala to Pakistan on the west coast. We went to one of these nesting sites or “rookeries”, snuggled amid a laid-back village called Velas, on the coast of Maharashtra. While half a million turtles nest on the Odisha coast, only a few hundreds visit the Maharashtra coast. Conserving these few turtles are important as they are critically endangered species.

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oriental plain tiger

Posted by on 11 Apr 2014 | Category: photography, prakriti

The plain tiger enjoys a celebrity status of being the first butterfly in the recorded history. It was depicted in a painting, with its distinct colors and patterns, in the tomb of Nebamun in Egypt, circa 1350 BCE – that’s more than 3300 years before!

oriental plain tiger, male at korlai, maharashtra

It’s a tiger not merely in its stripes and colors. It is a terror to potential predators too! Their bodies contain toxic alkaloids from plants, which they have devoured as a larvae. Birds and predators memorize and associate the unsavoriness of these butterfly species with their patterns and habits, and try to avoid them. This, in turn, is found to have evolutionary consequences in other “edible” butterflies, which ended up mimicing similar colors and patterns in order to escape from the predators.

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castle curlew and its church

Posted by on 20 Sep 2012 | Category: india, photography

Peeping into the Arabian Sea, nestling between Alibag and Murud, the popular tourist spots of Mumbaikars, is a world much unknown to the most of Maharashtra – Korlai.

Korlai is a 2 faced village, both by its geography and its soul. Both sides of the village are straddled by the sea, with the marathi fisher-folks on one side, and the indo-portuguese speaking villagers on the other side.

Korlai Fishing Village at the foothills of Castle Curlew

Standing prominent on the rocky headland side of the village is the 16th century Korlai fort, built by the Portuguese. Accounts, though hazy, says that it was originally ‘Castle Curlew’, built by Felipe Mascarenhas who was the 26th Viceroy of Portuguese India. When it was functional, the fort was protected on the inland side by a ditch, and accessible only by a drawbridge.

One of the interesting pieces of work inside the Korlai fort is the St Mathew’s church built circa 1630. Though now it is an abandoned, idling edifice, its features still give out the strategies and thoughts gone behind its construction.
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