Jacobin Cuckoo and the Somali Jet

BINOMIAL NAME: Clamator jacobinus

Since the beginning of my birding days, this was one bird that greatly fascinated me; a very ordinary looking black and white crested bird. In this post, I have tried to put together some very interesting bits and pieces of information that I have managed to glean and hopefully understand correctly about this species. As this is just a compilation of stuff read online and saved in a text file, I haven’t been able to give all the references about the sources.

A metaphor of deep yearning in Kalidasa’s “Meghadoota,” the chātak or the Jacobin cuckoo, pied cuckoo, or pied crested cuckoo is a member of the cuckoo order of birds that is found in Africa and Asia. It is a widespread resident as well as partially migratory in India. One population of the  Jacobin cuckoo (JC) is said to be a summer (monsoon) breeding migrant to India. It has been considered as the harbinger of the monsoon rains due to the timing of its arrival around late May or early June. This species has been widely mentioned in Indian mythology and poetry as a bird with a beak atop its head that thirsts for the rain.


There are 3 geographical races of the JC  (Freidman 1964):

  1. Clamator jacobinus pica: This is the migratory race which arrives in northern and western India from Africa in late May and early June, the popular rain visitor. It spends its non-breeding time in Eastern and North Eastern Africa. However, Rasmussen and Anderton (2005) suggest serratus as being the valid name for the Afro-Indian migrants.
  2. Clamator jacobinus jacobinus: The resident race of Sri Lanka and southern India (south of 15 degree N) which breeds from January to March. It disperses widely during the monsoon and may intermingle with the migratory race.
  3. Clamator jacobinus serratus: Resident race over a large part of tropical Africa south of Sahara.

Now, some very interesting facts about the migratory JC :

  • The migratory JCs are seen in northern and western part of the Indian Peninsula, generally north of the 15 degree latitude.
  • The migratory JCs arrive generally around the last week of May and first week of June (Ali and Ripley, 1987)
  • The arrival dates are earlier for coastal regions than the interior and also generally one week earlier along the Konkan coast than in Gujarat

What is the exact migratory route of these birds??

It is said that the JCs take an Arabian Sea route along the shores of the Arabian Peninsula. Jamdar (2005) suspects the role of the Somali Jet, a fast stream of air over the Arabian Sea, in carrying the migratory population from Africa to Asia.

What is the Somali Jet and its exact role?? jacobin-pranav1

The Somali Jet is a low level jet stream that forms in the northern summer over the western part of the Indian Ocean off the Madagascar Coast. This jet stream after formation in April off the Mauritius Coast moves NE towards northern Madagascar and then runs over the plains of Kenya, Somalia and southern Ethiopia during May covering the non-breeding range of the Jacobin Cuckoo that migrates to India. The Jet traverses the northern part of the Arabian Sea before reaching the Indian shore in June. The Somali jet is almost 200 km wide (Halpern and Woiceslyn 1999) and reaches the Indian shore like a front. It mostly strikes the western shore of India, north of 10 degree N. Hence probably the migratory JCs are mostly confined to the northern part of the Peninsula. The formative period of the Somali jet, when the winds are still to be well established is the time when the migratory JCs arrive in India, i.e. the last week of May and first of June. This cuckoo being a slim myna-sized bird with a weak flight might be preferring this weaker Somali Jet. The JCs use the landward section of the current close to the Arabian shoreline. The front first touches Konkan coast and then moves towards Gujarat. Hence it might be sighted earlier along the Konkan coast than in Gujarat.

Jacobin Cuckoo and Common Rosefinch; Birds of two different migration cycles seen at the same time – One a summer (monsoon) visitor & the other a wintering guest.

No ringing evidence exists regarding the actual migration as per what I have read.


Brood parasitic cuckoos lay their eggs in a host’s nest and rely completely on the hosts to do parental care of their young. In India, the hosts for the Jacobin Cuckoo are mainly the Turdoides babblers. Excellent egg mimicry is seen and the color of the JC egg matches the egg color of the host, typically turquoise blue. Unlike other cuckoos, the Jacobin Cuckoos nestlings are non-evictors of host’s eggs but the parasite chick may hatch earlier and monopolize the parental feeding. This reduces the chances of survival of the host chicks.

I hope you enjoyed reading about the Jacobin Cuckoo as much as I did while putting together the information…!!! 😀 🙂

(Both these amazing Jacobin Cuckoo images have been contributed by young enthusiastic fellow birder, Pranav Deo)


– Until the next post…Ciao friends!!!