This time we look at the arrival patterns of warblers. (Please note that each sighting is shown as a vertical black line.)

From the above illustration we can see that all the above four warbler species start arriving  in early September. However, Blyth’s Reed-warbler appears to stay around the longest (until May). Booted Warbler leaves about a fortnight earlier than Blyth’s (mid-April), while Lesser Whitethroat and Hume’s Leaf-warbler stay only until the second half of March. These interesting patterns have only been revealed thanks to observations logged in by keen MigrantWatchers.

The following figure depicts the arrival patterns of Sandpipers and Common Redshank. (Note that each sighting is shown as a vertical black line.)

The above results show that the Common, Wood and Green Sandpipers, and the Common Redshank all begin arriving in July itself. The Green Sandpiper is the first to leave (early April) while the Common and Wood Sandpipers stick around until the beginning of May. Most Common Redshanks, too, have flown back by early May. Many thanks to all MigrantWatchers whose observations enabled us to come up with these summaries!

In continuation with our presentation of present arrival patterns of our most-reported species, we now feature Black Redstart, Red-throated Flycatcher, Asian Paradise Flycatcher and Common Stonechat.

As in previous summaries each sighting is shown as a vertical black line.

It is apparent from the above chart that Black Redstart and Common Stonechat arrive in mid-September and generally leave by March-end. Red-throated Flycatchers arrive slightly in late September and return by April-end. The Paradise Flycatcher, which is an intra-subcontinental migrant, has records spread over the entire year. (Please note that this summary has only been possible thanks to your contributions!)

Here we present arrival patterns of some of the most-reported species: the Barn Swallow, Brown Shrike, White Wagtail and Western Yellow Wagtail.

Like in previous summaries each sighting is shown as a vertical black line.

As you can appreciate from the above illustration, Barn Swallows and Brown Shrikes arrive around late July/early August and nearly all of them leave by April. The wagtails normally arrive in early September and usually are gone by April-end. (This summary has only been possible thanks to your contributions!)

Does the arrival of the Pied Cuckoo herald the onset of the monsoon? The Pied Cuckoo Campaign was launched in 2009 to collect information to assess this age-old belief.

More than 600 sightings of this wonderful migrant have been contributed by over 200 MigrantWatchers so far; the first sighting dates among these were compared to monsoon arrival, as available with the Indian Meteorological Department (see the graph alongside). Each dot shows the earliest Pied Cuckoo report (after 1 May) for a broad location (an area roughly 200 Km across).

The results are fairly clear: Pied Cuckoos arrive before the monsoon in most parts of central and northern India (they are resident in southern India). You can see this from the pattern that most dots in the picture to the right are below the dotted horizontal line.

But the degree to which the arrival of the Pied Cuckoo precedes the monsoon varies from place to place, as can be seen from the scatter of the dots within each year. And even for the same general location, this varies from year to year (see how the coloured dots are in different places in different years).

What appears to be happening is that, where the monsoon arrives early, Pied Cuckoos arrive a few days before monsoon onset; but where the monsoon arrives late, the cuckoos arrive well in advance of monsoon onset.

So, overall, the old belief is true, and Pied Cuckoos tend to arrive before the monsoon — but to different degrees, depending on when the monsoon begins at each place.

Also see this article on Pied Cuckoo migration.

By Mousumi Ghosh (with inputs from Umesh Srinivasan)

Tips for Identification

If you’re keen to start leaf warbler watching, you just need an ear for it! You can start with the commonly encountered leaf warbler species in our backyard like Hume’s Warbler (in North India) and Greenish Warbler (in South India) and fortunately, both are extremely vocal. Anytime I want to hear a Hume’s Warbler in winter here in Dehradun, I just have to strain my ears a bit and sure enough I can hear one (yes, it’s that common during winter in North India). Both are territorial in winter and call incessantly guarding their precious trees from the canopy. So, let’s get acquainted with some of the commoner species which visit us in the plains in winter (Here is an illustration to help you with some of the terms commonly used while describing warblers):

Hume’s Warbler (Phylloscopus humei):  One of the commonest leaf warblers, it has an overall dull colour with greenish upperparts and off-white underparts. Other features include a long supercilium, weak/absent crown-stripe, prominently pale tertial edges, no white margins to the tail, one prominent pale wing bar (just a faint vestige of the second wing bar may be visible). The darker legs and lower mandibles are diagnostic. Hume’s is among the smaller of leaf warblers; it breeds near the tree-line and is partial to birch forests in the summer. In the winter it is one of the commonest species found all over the plains of North India. It’s solitary in winter and calls incessantly from the crowns of trees. Call: A repeated, disyllabic ringing tiss-yip, buzzy wheezing tzzzeeeeeu, often given interspersed with calls.

Greenish Warbler (Phylloscopus trochiloides): A common winter migrant in peninsular India, it is one of the larger leaf warblers. It has greyish-green upper parts and off-white underparts. Absence of coronal stripe, yellowish-white supercilium and a single wing bar are other features which help distinguish this species.

During the breeding season, Greenish Warbler occurs close to the tree-line in mixed-conifer forests and rhododendrons. In winter, it is territorial and partial to the canopy, from the top of which it calls incessantly to defend its precious territory. Call:  a disyllabic tisswit or chiswee.

Lemon-rumped Warbler (Phylloscopus chloronotus): This tiny little leaf warbler gets its name from its pale yellowish rump which is frequently exposed as it hovers at the edge of leaves to pick arthropod prey. It’s a rather active bird with olive green upperparts, whitish underparts, dark bill and pale legs. The head is rather distinctive with a prominent pale yellow crown stripe, a broad yellowish supercilium and a very dark eye-stripe which broadens behind the eye and hooks under the ear coverts. Typically two yellowish wing bars are visible, the lower one being larger and more prominent. This species is an altitudinal migrant, spending the summer in the mixed coniferous, oak and rhododendron forests and retreating to the foothills in winter where it joins mixed-species flocks to forage mostly in the mid-canopy and undergrowth. More than two may be part of the same flock, daintily hovering around the vegetation and is an absolute treat to watch! Call: A high-pitched tsip or uist.

Apart from the above there are a number of other species of Phylloscopus warbler that can be observed in the Indian subcontinent. Most of these species migrate over long distances to winter in the Indian plains and peninsular India, some show an altitudinal migration, and a couple of them are resident throughout the year. Here is a very handy key for their visual identification compiled by Umesh Srinivasan.

This concludes our three-part series on Phylloscopus warblers. We hope that these articles helped you in identifying the main species in this difficult group and also provided interesting information about the ecology of leaf warblers. We’d like to know if you liked this series and if you’d like us to run more such articles in the future on the MigrantWatch blog. Please do send in your comments and feedback at mw@migrantwatch.in. 

You can read Part I and Part II in this series of articles on leaf warblers.

Continuing our presentation of year-wise arrival patterns, here we show the results for Barn Swallow.

Please note that each sighting is shown as a vertical black line.

From the above illustration it is evident that Barn Swallows usually arrive around late July/early August and nearly all of them leave by April.

You can explore the Barn Swallow sightings on MigrantWatch here.

In this post we share with you the arrival patterns of Rosy Starling as it moves across the country. As is evident in the illustration below, Rosy Starlings arrive early (around mid to end July) in northwestern India, but then take three to four months to trickle down to the southernmost States!

You can look at all Rosy Starling sightings in the MigrantWatch database here. Many thanks for all who contributed their observations.

Note on how this map was made: you might wonder why, given there are many hundred Rosy Starling records in the database, there are so few points shown here. In each migration season (July to June; five migration seasons in all) we took the earliest sighting for each State; and these State-wise early sightings are depicted here. So, to reiterate, the points shown on the map are the earliest sightings for each State. Multiple  points within a State represent different migration seasons. The labels on the left describe the typical pattern for a given State or region, taking all migration seasons into consideration. You can download the State-wise first sightings in an Excel file here.

As we compile the MigrantWatch 5-year report we are looking at migration timings of various species. Here we present a visual summary for Grey Wagtail over the five years of data collection.

Each sighting is indicated with a vertical black line, just as in this image of sightings of several species.

It is apparent that most Grey Wagtails arrive in September, although their arrival begins in August itself. The earliest record of the season was by Urmila Ganguli on 1st August 2007. Most of them leave by April. Although the chart shows a couple of sightings in June, both these observations are actually from Himalayan areas where the Grey Wagtails likely breed.

To look at all Grey Wagtail sightings in the MigrantWatch database please click here.

Some extracts from Douglas Dewar’s A Bird Calendar for Northern India, published in 1916. Have you heard the a-onk of a Brahminy Duck (Ruddy Shelduck), or a Coppersmith say wow, or the honking of geese overhead in the night?

Taken, with grateful thanks, from Project Gutenberg.