Thursday 16 February 2012

FOTD #1 - Marsh Warblers

After reading the book "Why Birds Sing" I gathered a bunch of facts that I found interesting and wanted to share. The list ended up being too long for one blog post so I'll break it up into a series of facts - Fact of the Day (FOTD's) - ideal for blog filler ;) But I won't be posting one daily so it's more like Fact of the Intermittent Day (FOTID).

FOTD #1:

Listen to a Marsh Warbler while you're reading about them ;)

Marsh Warblers are a species of warbler that live in marshes (duh) in Europe. They have a long, continuous song that can last up to 30 minutes! Prior to the 1970's, scientists and naturalists believed that the song consisted of parts that are mimicked from other birds in its territory and of its own parts that are unique to the species (i.e. non-mimicked parts). This changed in 1976, when a naturalist took her first trip to East Africa, the wintering grounds of the Marsh Warbler, where she learned the sounds of commons birds in the area. When she returned to Belgium the following year, she was astounded to hear the warblers perfectly imitate many of the African birds. Woven into the marsh warbler's extremely complex song she heard Black-eyed Bulbul notes and bleating Bush Warblers calls, along with colorfully named singers such as the Blue-cheeked Bee-eater and the Fork-tailed Drongo. The Marsh Warbler turns out to have no original song syllables at all. It even imitates birds it can only hear en route to its winter grounds: passing through Tunisia, it picks up tunes from the Boran Cisticola and the Vinaceous Dove. The naturalist had discovered the one bird that can recount its migratory path as a kind of songline, where the journey is mapped into the music itself.

Why has the bird evolved such an incredible mimetic song, perhaps the most complex in the world? Not for mating purposes. Female Marsh Warblers choose mates based on the male's territory, not the quality of his song. The females seem rather uninterested in its awesome complexity. As the song is so complicated and it takes over thirty minutes of continusous singing to get the full repertoire, females would need to sit and listen for ages to evaluate a male's musical skill. Of course they do no such thing. As soon as a female appears, the male stops his singing. Concert over. He then devotes himself to helping her find the best nest site, giving only brief snatches of song along the way. She may never get to hear what her mate can do!

Quoted from "Why Bird's Sing". A review of the book will come eventually.

Photo from here

A bland looking bird, no wonder it needs to attract mates with a respectable territory!

Don't forget about the Bird Song Quiz below. So far one person has them all correct.