JUST as humans do with their own speech, birds form regional dialects with their songs and calls and traditionally stick to these to attract mates and defend territories, but a change of tune by the white-throated sparrow in Canada has stunned scientists.

 

The white-throated sparrow?

They are plump, pretty little sparrows, with a largely brown top half and grey feathers below, as well as a striking black and white striped head, a bright white throat and yellow between the eye and the bill. They breed in New England and Canada.

 

In the UK?

There have only been a handful of sightings in the UK over the years, including one in Cornwall in 2010. In winter, they tend to migrate to North America and California.

 

What are they up to?

They have changed their tried-and-tested tune, with the shift from the old song to the new going viral across Canada, journeying 3,000 kilometres in the last decade.

 

What was their old song?

Biology professor, Ken Otter, of the University of Northern British Columbia, has published a study on the developments, stating that their old three-note-ending song was described as sounding like ‘Oh My Sweet Canada Canada Canada Canada’, so that the Canada has three syllables.

Mr Otter told the Canadian Press: “It’s a da-da-da, da-da-da, da-da-da, da-da-da sound. That’s the traditional description of the song going back into early 1900s.”

 

Now?

This historic song has essentially been replaced by a two-note-ending song. Mr Otter said: “The doublet sounds like Oh My Sweet Cana-Cana-Cana-da. They are stuttering and repeating the first two syllables and they are doing it very rapidly. It sounds very different.”

 

And this is unusual?

It’s described as an “unprecedented rate of song-type transition in any species of birds”.

Most bird species are said to be slow to, and indeed unlikely to change their songs, preferring to stick to the birdsong they know over time has helped them defend their territory and attract mates. And although populations of sparrows and other birds can change their tunes, alterations tend to remain regional and not go viral.

 

It’s changing thinking on dialect generally?

The professor said “it’s like somebody from Australia arriving in Toronto and people saying, ‘hey, that sounds really cool,’ mimicking an Australian accent and then after 10 years everybody in Toronto has an Australian accent. That’s why, at least within the scientific community, it’s getting so much interest. It is completely atypical to what you would predict around all the theories that you have about dialects”.

 

There is some precedent?

In a 2017 study by George Mason University in Virginia, birds in Rock Creek Park in Washington DC were found to alter the way they sang when traffic was hurtling along nearby roads, singing in shorter bursts. Although they were heard more easily over the noise, though, the research found other birds didn’t pay attention.

 

Here, though, it’s viral?

Researchers are still investigating what has made the new tune so popular, as research found the white-throated sparrow’s change went viral, spreading rapidly across Canada.

Professor Otter said: “Originally, we measured the dialect boundaries in 2004 and it stopped about halfway through Alberta. By 2014, every bird we recorded in Alberta was singing this western dialect, and we started to see it appearing in populations as far away as Ontario, which is 3,000 kilometres from us.”

 

Now?

As another birdsong variant is being explored - found to be spreading rapidly in the Rocky Mountains - research continues, with experts looking into the role of the female response and possible preference to the different endings influencing the change in tunes.