Thursday, March 31, 2016

Jerdon's Leafbird


Since we started this little bird bath two years ago, there has been a gradual increase in the number and type of birds that visit it all through the day. Since the last few weeks we noticed a pair of Jerdon's leafbirds ( Chloropsis jerdoni ) regularly arriving for a bath every evening. Poor light in the secluded area meant that photographs came out blurred. Yesterday however, I did some pruning of the nearby trees and today there was light.
I was also delighted to have both the male and the female bird in the same frame and in the above photograph the bird with the black throat patch is the male and the one with a light blue patch is the female.


Jerdon's leafbird is named in honour of Thomas Caverhill Jerdon a British physician, who while working in India from 1836 to 1870 studied the flora and fauna of the region where he was posted and eventually covered a large portion of India.

Jerdon's studies covered not just birds but also  plants, ants, amphibians, reptiles, birds and mammals.

Several species of plants including an entire genus (Jerdonia, ex. Indian Violet), three species of lizards, three species of snakes and a whopping thirteen species of birds are named after him. Well if that was not enough, Impatiens jerdoniae is named after his wife Flora Jerdon.


In the two years that we have maintained a bird bath, I have made the following observations about the birds choice for a bath.
Our initial bird baths were not successful because they were too deep. After trying various household items, saucers  seemed to be the item of choice.
Birds prefers shallow sided vessels, from where they can drink without slipping into the water.
A rough surface like a stone, will help the bird to grip and small birds always prefer saucers with stones and larger ones like crows and cuckoo's saucers without stones.
Ensure the saucer is on a sturdy, slightly raised surface and will not tip over. The stone serves this additional purpose.
We change water twice a day, since the heavy rush of birds during summers empties the shallow saucers in 3 to 4 hours. Birds visit soon after feeding, so morning and evenings are rush hours.
A simple bird bath is all that you need to always have birds around you- Why cage birds and steal their freedom away.   

Thursday, March 24, 2016

Common Greenshank


Hidden somewhere in my hardisk was this photograph I clicked in January this year at Neura wetlands in Goa. It is when I posted the Redshank yesterday, did I remember about the Greenshank.

The Common Greenshank (Tringa nebularia) is very similar to the slightly smaller Marsh sandpiper and especially if the Marsh sandpiper is well fed then identification can go haywire. There are slight variations in colours and patterns that experienced birders readily use, but I prefer to watch the bird beak. the Greenshank has a slightly upward curving beak, while the Marsh sandpiper has a straight beak.

The bird breeds in sub-arctic region (anywhere from Scotland, northern Europe to North Russia) and visits in Indian subcontinent during winters.

If you love reading, and especially about nature, then there is a wonderful book that I can recommend, that I personally enjoyed. It is titled  'Greenshanks' by Desmond Nethersole-Thompson, Maimie . They spent days and years watching, observing and studying Greenshanks and this book is a wonderful compilation of those observation.

Wednesday, March 23, 2016

Common Redshank


A shank is the part of a leg, from the knee to the ankle- hence it's a no brainer why this bird is called the Common Redshank (Tringa totanus ).
The bird, breeds in NW Himalayas and is a winter visitor to Goa. Now that summer is here- I guess its soon migration time for this guy.
I spotted the bird, when boating along the mangroves of the Salim Ali bird sanctuary this Sunday and it was a wonderful feel to be among the serene waters of the Mapusa river and meander along the roots of the mangroves .


Everywhere that we sailed we saw the coast bordered by mangroves. At many places however mangroves were cleared to build fish farms and retaining walls for the fish farms. The picturesque red mangroves had produced aerial roots that appeared to grow like stilts from branches. Prop roots arching from the side of trunks gave the trees a spider like appearance.

 These dense tangles of roots, penetrate the water and act as sediment traps. Mud and debris washed in with the tides and dead leaves falling from trees are caught among the roots and gradually accumulate to build dry land. It is this slow process that created the Salim Ali Bird sanctuary, where we went birding and massive coastal areas like the Sunderbans and Everglades.
The labyrinth of roots make it difficult for marauding animals to travel through mangrove swamps (man included) and thus the birds, like the Redshank featured today favour it as nesting and resting site.


The hanging spaghetti like objects in the above photograph are called Propagule. Most of the trees that we saw were the Rhizophora mucronata commonly called the red mangrove. The propagule is how the tree propagates. Generally seeds fall on the ground and then sprout and eventually grow into plants and trees. The mangroves however have evolved a slightly different mechanism. If the seed of a mangrove plant were to fall like any other plant, it would float in water and never anchor itself to the river bed.  So after the Rhizophora mucronata  flowers and pollinates, the seeds begin to develop when attached to the tree itself. These can grow upto a meter long and when mature detaches from the mother plant and roots itself on the ground below to grow into a new tree. 

Tuesday, March 22, 2016

Darter


Perched on the top of a mangrove tree was a solitary Darter (Anhinga melanogaster) and on closer examination it turned out to be a juvenile bird.
The darter is named so, because unlike many birds that catch fish between their beaks, the darter impales its prey like a skewer piercing kebabs.
Darters and their relatives the Cormorants, although spend a great deal of time diving in water, have their feathers so constructed that they get thoroughly wet. This is advantageous to these birds because by losing the air trapped beneath them, they become much less buoyant and so can dive in pursuit of fish with greater ease. When they have finished fishing, they have   to stand on the rocks wings outstretched drying themselves.
If you remember your science classes in High school or higher secondary, then you will surely recollect the tiny little fruit fly (Drosophila melanogaster ) - that tiny fly and this large bird both share the same species name; melanogaster meaning black bellied.
The species name, Anhinga, comes from the Brazilian Tupi language meaning snake bird. When swimming only the colored neck of the darter appears above water so the bird looks like a snake ready to strike and hence the name. 

Monday, March 21, 2016

Mugger Crocodile

A birding trip on Sunday on the Mapusa river in Goa had a surprise in store for us. Resting among the mangrove trees that line the Salim Ali Bird sanctuary, were two Mugger Crocodiles (Crocodylus palustris Latin for 'Crocodile of the marsh/ swamp). 
The name "mugger" is adapted from Hindi word magar, meaning crocodile- so the name basically means crocodile crocodile. 
These shy crocodiles are one of the three crocodiles that are found in India and because of their dwindling number they are classified as Vulnerable. 
Crocodiles are related to birds; as surprising as that may sound they shared a common ancestor 240 million years ago.   


The crocodiles were very well camouflaged and if not for our sharp eyed boatman/ guide we would have definitely not spotted these awe inspiring crocodiles.
Living on the banks of the gently flowing Mapusa river, the crocodile probably survives on a diet of fish and perhaps occasionally indulges on birds.



One of the classic way of differentiating a crocodile from an alligator is by looking at its teeth. In the above photograph, you can see the fourth tooth pointing upwards. When their jaws are shut, crocodiles flash some teeth that point upwards, unlike alligators.


So were crocodiles always part of Goa's ecosystem- perhaps yes, but there is an interesting story first narrated by the 16th Century chronicler Joao de Barros who swore that the crocodiles were introduced by 'Adil Shah of Bijapur, as a guard against surprise attacks and to prevents slaves from escaping'. Whatever be the case, the Portuguese themselves regularly sent prisoners of wars and condemned criminals as an a la carte item in the crocodiles otherwise sea-food diet.
Despite all the horrible history, the crocodiles did not appreciate our presence and a few minutes later they quickly scampered into the water.