The Pied Cuckoo in 2010 – Mousumi Dutta
First arrival of the Pied Cuckoo in 2010 in relation to the onset of the Southwest Monsoon
by Mousumi Dutta
Mousumi Dutta is a frequent contributor to the MigrantWatch database. She is an avid birder, and spends her spare time on bird and wildlife conservation. She works with the Indian Meteorological Department, and so has a particular interest in bird migration. Mousumi’s MigrantWatch sightings page is here.
India’s climate is dominated by monsoons. Most of its annual rainfall (86%) occurs during the Southwest monsoon months. The monsoon is a key influence on agricultural output as well as the overall economic growth of India. From ancient times it has been believed that the onset of the monsoon is associated with the appearance of the Pied Cuckoo Clamator jacobinus.
The Southwest monsoon normally sets in over Southeast Bay of Bengal on 20 May and then over Kerala on 1 June. An analysis of the first sighting dates of the Pied Cuckoo and the onset of the Southwest monsoon for the year 2010 (see figure below) shows a fairly systematic pattern. In general, the first sighting of this species in a State is 20-25 days in advance of the onset of the monsoon in that State. This appears to be earlier, relative to the monsoon, than reported for last year.
These patterns indicate an interesting relation between the onset of the monsoon and the arrival of Pied Cuckoos. Long term studies are needed to clarify the details of the relationship between the monsoon winds and Pied Cuckoo migration.
Methods
First sighting dates (after January 2010) for Pied Cuckoos for each State were taken from the MigrantWatch database. (Maharashtra and the four southern States were excluded.) Dates of the onset of the monsoon for each State are taken from the Indian Meteorological Department’s monsoon pages (click on “Northern Limits of Monsoon”). The data used to generate the figure are given below. The links under “Reported by” point to the sighting page on MigrantWatch.
State | First Sighting | Onset of Monsoon | Reported by |
Orissa | 16 May | 13 June | Aditya Panda |
West Bengal | 17 May | 14 June | Supriyo Ghatak |
Gujarat | 30 May | 16 June | Nandita Amin |
Madhya Pradesh | 10 June | 4 July | Anand Kumar Bhatt |
Uttarakhand | 27 May | 5 July | Sharad Khanna |
Chandigarh | 6 June | 5 July | Vikram Jit Singh |
Delhi, including NOIDA | 31 May | 5 July | KB Singh, email to MigrantWatch |
Haryana | 22 June | 5 July | Vikram Jit Singh |
Himachal Pradesh | 29 June | 5 July | Devinder Singh Dhadwal |
Rajasthan | 24 May | 6 July | Saandip Nandagudi |
If you would like to make your own visualisation and analysis of Pied Cuckoo sightings, you can download all 300+ records here. Please share your findings with everyone at MigrantWatch – send us (mw@migrantwatch.in) a small blog post and we will put it up.
Gaurang Shukla says:
November 26th, 2010 at 10:32 am
Mousumi,
First of all, congrats for ur efforts, very interesting pattern are emerging but i think more data for long period are required to establish a relationship b`ween migration of P.Cuckoo and monsoon.
gaurang
Prasanna Parab says:
December 7th, 2010 at 11:56 am
Mousumi ji,
Great efforts you have put in this work….. Good to see the results and a lot of knowledge gained from it.
Prasanna Parab
digambar gadgil says:
December 10th, 2010 at 1:30 pm
it is surprising why nobody from mashtra keeps track when this state receives rain before most of these states
Shriram Vaijapurkar says:
December 19th, 2010 at 7:57 am
Gadgil Kaka,I and few others are among the participants in year 2009, who kept and recorded the track of Pied Cuckoos. But unfortunately all that data has been lost by migrantwatch. This year it is to express sadly that no Cuckoos bird seen in MERI or the places where I moved. May it be my fault or badluck, Sir.
Suhel Quader says:
December 23rd, 2010 at 3:58 pm
Dear Shriramji,
I just thought I would clarify that no data from 2009 has been lost. It is true that some sightings, entered over a few weeks between 19th August and 26th Sept 2010 were lost, but the vast majority of records entered into MigrantWatch are safe!
For example, if you click here, you will see all Pied Cuckoo sightings submitted to MigrantWatch from Maharashtra. These include four of your sightings (all in 2009), plus 31 other records. This season, there have been three Pied Cuckoo sightings submitted from Maharashtra so far, the earliest on 20 July 2010 by Kaustubh Pandharipande from Karanja Lad.
Mousumi Dutta, who has authored this blog post, chose to include only those data from Gujarat, Madhya Pradesh, Orissa and further North. But, of course, anyone is welcome to download the entire dataset and re-analyse it in a different way. We would be very happy to post the results of any further analysis! This is one of the major goals of MigrantWatch — to encourage participants to synthesise the information and interpret the patterns of bird migration that emerge.
Thank you,
Suhel (for MigrantWatch)
Mousumi Dutta says:
December 25th, 2010 at 6:02 pm
Thank you all. As I have told this is a very preliminary as well as experimental study. In this study I have included only those states situated above 20 deg lat. In case of Maharashtra I found only one reporting from Nagpur (above 20deg), in that case the date of reporting and starting date of looking for this bird on the same location was same. Considering that the date might not be the first arrival at this point, I have excluded this data.