On 21 Oct 2011, MigrantWatch reached 10,000 records in the database; and we thought this is a good occasion to summarise how we got here, and to express our appreciation for the participants whose efforts form the backbone of the project.

As you can see from the chart to the right, the total number of registered participants in MigrantWatch showed a big jump in the second half of 2008, and has been rising steadily since then. From January 2010 onwards, we have been getting an average of 12-16 new registrants per month. The total now (as of 17 Oct 2011) stands at 1,334.

Of course, not everyone who registers on the website actually participates by contributing sightings. In fact, only about 550 of those who have registered are actually contributors, having uploaded at least one sighting to the database. The rise in the number of such contributors has been relatively slow since January 2010, averaging about 1-2 every month.

The total number of sightings in the database has grown in fits and starts over the years, showing a jump in the second half of every year (that is, at the start of the winter migration season). The total now stands at a whisker over 10,000.

Who are the MigrantWatchers who have built up the database to this level? Many contributors have uploaded just a single sighting to MigrantWatch; and on the other end of the spectrum, a few have many hundred records under their belt. We would like to emphasise that all contributions are valuable, because they add to the storehouse of information about our birds. So we thank all contributors, regardless of how many sightings that have uploaded. But in addition, we wanted to highlight some particularly active MigrantWatchers – those who have contributed the most to this open pool of information. These star contributors are listed in the table below, in decreasing order of the number of records submitted to MigrantWatch, separated for First sightings of the season, Last sightings of the season, General sightings, and All sightings put together.

So these are the participants who have contributed the largest number of records to MigrantWatch. But what about regularity of reporting? Are there participants who have contributed consistently, month-by-month to the database? The most consistent participants are listed to the right. A consistency score of 1 means that a person has contributed records every month since joining MigrantWatch; and a score of 0.5 means that he or she has contributed records in 50% of the months since joining.

Again, thanks to all of you who have generously contributed your time and efforts to MigrantWatch. As the project begins to accumulate enough records so that interesting patterns emerge and new findings are made possible, we hope you will keep in mind that all this is made possible solely through your contributions!

The 10,000th report on MigrantWatch was uploaded two days ago, on Friday, 21 Oct 2011, with an accompanying photograph. This migrant sighting comes from Mandar Pawgi, Aniket Sayam and Nikhil Wadatkar from Amravati in Maharashtra. Here is a description of the sighting, in Mandar’s words:

On 20th October morning, we made our way to a very famous birding spot in our city, the Wadali tank — a haven for birdlife and birdwatchers. On our arrival, we were welcomed by waterhens, coots, ducks, kingfisher and many other waterbirds. For the past two weeks we had been highly excited to see migratory birds at the tank. This morning, on the eastern corner of the lake, we saw a few waterhens moving actively in the sunlight within the net of Lotus leaves. As we watched them, suddenly Nikhil saw a very beautiful bird with brilliant colours and white spots on the wings. He excitedly called us as this was a new species to us. All the activity put the bird to flight, but before it did so, Nikhil managed to take a few snaps (one is shown below). We were extremely happy to see a new species, which we later confirmed as an Eastern Baillon’s Crake. According to available records the bird is a vagrant at Wadali Tank and surrounds.

The smallest rail found in India, the Eastern Baillon’s Crake Porzana pusilla breeds in Kashmir and in Central and East Asia. This quail-sized swamp bird migrates south and spreads across the subcontinent in September-October, migrating back to its breeding grounds in March-April. It frequents jheels, ponds, marshes and even irrigated cropfields, where it feeds on seeds of aquatic plants, snails, worms, and insects and their larvae.

The greenish bill, white ‘marble’ pattern on the brown upperparts, and short tail separate this species from the much rarer Little Crake Porzana parva, which has a red base to its bill, with wings projecting out more from the body. Eastern Baillon’s Crakes are mostly solitary or are seen in pairs. Because they are more secretive than other crakes, they are relatively difficult to observe, and are easily missed — and there are only 17 reports of this species in the MigrantWatch database so far.

Congratulations to Mandar, Aniket and Nikhil for an excellent sighting, which looks like a juvenile bird from the accompanying photo. Appropriately, the 10,000th MigrantWatch report comes from smack in the centre of the country!

Soon to follow on the blog: a description of the accumulation of sightings to 10,000, together with an appreciation of the MigrantWatchers whose contributions have made this happen.

By Suhel Quader

Up to 11 Oct 2011, 9900 sightings had been reported to the MigrantWatch database. This information is meant to be used, so at MigrantWatch we are gathering our thoughts to put together a comprehensive summary of the data that the project has gathered since it started in July 2007. When it is ready, we’ll send the report to all MigrantWatch participants, with grateful thanks.

In preparing the report, we have been thinking about how best to show a picture of arrival dates of different species (for example, see a crude attempt here). In this post, I’d like to show you some first attempts, and ask for your feedback on improvements and additions.

The picture below shows sighting information from all years of the project (until 11 October 2011) and across all India, for the 23 winter migrants for which there are at least 100 records in the database. Each short vertical line depicts a sighting. The dates are arranged from July to July, corresponding with a typical migration season (rather than a calendar year). To help see the patterns of first sightings, it’s better not to focus on the very earliest sighting dates and instead look at when the main concentration of first sightings is. The yellow boxes in the picture depict when the earliest 1% to 5% of sightings happened. (This is just like the percentile rankings that students get on some exams.) The width of the yellow boxes indicates how spread out the arrival is for each species: wide boxes mean that the earliest sightings are spread out considerably in time. In the picture below, species are arranged in order of the earliest 1% of arrivals (ie, the left edge of the yellow boxes).

What does this summary tell us? We see that shorebirds form a large proportion of early arriving species, which confirms what I’m sure many of us have casually noticed. Ducks tend to turn up a bit later, as also wagtails and warblers. Although only a few MigrantWatch participants keep an eye out for departing migrants (and so information from the end of the season is thin), it seems as though most migrants have left the country by the beginning of May. The departure appears particularly abrupt for species like Rosy Starling, Common Sandpiper, Greenish Warbler and Blyth’s Reed-warbler. Individuals of other species hang on for a while, and several shorebirds have been seen well into June, possibly birds who have decided to skip their return flight altogether and instead over-summer in India.

Of course, this all-India picture obscures variation in migration dates in different parts of the country: migrants don’t suddenly appear everywhere at the same time! To try to look for geographical differences, we have grouped sightings into five regions (excluding the Andaman and Nicobar Islands, and Lakshadweep): North-East, North-West, North, Central, and South. Region-wise sightings for two migrants are illustrated below.

Rosy Starlings first appear in the North-West, as might be expected from their breeding grounds (Eastern Europe to Kazakhstan). Their early initial arrival, in beginning July, is followed by a gradual and unhurried trickle-down to other parts of the country (except to the North-East, where the species does not occur). It takes nearly two months for these birds to reach the South. In contrast, departure dates are more uniform, all around end-April, presumably as the birds hurry back en-masse to their breeding grounds.

In contrast, White Wagtails put in a much later first appearance, starting in the North-East and North (apart from a couple of oddly early sightings in the South). They then appear relatively rapidly in North-West, Central and South — in roughly the opposite East-West sequence as Rosy Starlings. Departure of White Wagtails is less clear, because of the low number of observations.

Do these visual depictions of MigrantWatch information make sense? Are they useful? How can we improve them? Are they too simple? Too complicated? Please do let us know in the comments below; we would like to summarise the data in a manner that is of most use and interest to you! (Of course, as always, you can play around with the data yourself — just login and click on view data/maps to download the entire database.)

And please don’t forget to report your migrant sightings. MigrantWatch is no more and no less than the sum of contributions of all participants; to paint a clear picture of bird migration, the more reports (of first, and last, and general sightings) the better!