Climate Change Subtle Indicator: Sedentary Cattle Egret in Akure
By DEPO ADENLE
From elementary school through secondary school AND university, cattle egrets usually arrived during the beginning of the Harmattan season, usually the coolest and driest period of the year. As soon as the rainy season began which is warm and humid, they usually disappeared.
While I do not know exactly when the trend changed, two or three years ago, I started noticing these white pretty birds that migrated to southwestern Nigeria during the Harmattan moving down pretty early, say, August.
Picture Credit: Depo Adenle, July 06, 2012.
Now, it is a different story as they have virtually refused to migrate away from the southwest.
The situation as regards the migration of this bird is in agreement with Wikipedia’s essay on it which notes that some populations of Cattle Egrets are migratory, others are dispersive, but distinguishing between the two can be difficult for this species. In many areas populations can be both sedentary and migratory. In western Africa migration is in response to rainfall.
I’ve spent most of the last ten months at Akure, a city in the rainforest belt of Nigeria. The period covered the last part of last year’s rainy season and continuing through the dry season and right into this year’s rainy season.Throughout, the cattle egret has been nesting on one spot along the Akure-Owo Express Highway.
Since this is at variance with the supposed migratory pattern of these birds, this seems an indication of changing seasons in this area of Nigeria, and I became curious, especially why a flock that numbers in the hundreds has made its home in the same place at Akure up till now.
Is this another subtle pointer to the global climatic change?