I was watching a documentary about the Himalayas the other day.
One of the species mentioned was the bar-headed goose and its grueling annual migration, which takes them from the high plateaus of Mongolia, where they spend summer to India, where they stay over winter. To do so they have to cross some of the toughest terrain and highest peaks in the world. According to the documentary, in order to do so, the geese fly at heights of up to 9000 meters.
However, research by Charles Bishop of Bangor University in Wales, UK, whose team tracked a flock of geese across the mountains seems to indicate this is not quite so straight-forward. Their findings indicate that rather than flying high-up and straight-ahead, the birds follow a roller-coaster, terrain-hugging flight route at heights rarely above 150 meters over ground level. By doing so, they save up to eight percent of energy, which is significant, in view of the fact that the bar-headed goose is a fairly heavy bird and that they spend the entire flight flapping their wings rather than gliding. The predominant gain of this strategy comes from higher oxygen content and air pressures at the lower altitudes.
But once more, as I have discussed before, there was one thing that struck me about all this:
The geese do all this incredible stuff, essentially the equivalent of running multiple, successive marathons at great height – incessantly honking.
Now, if I had to put my finger on one single, easy way to save energy, I would suggest to knock off the honking. I think, apart from anything else, I would find it more than just a bit annoying and monotonous if that were the only in-flight entertainment all the way from Mongolia to India. Seriously. Ok, it may be a nice, group building exercise initially, but it wears a bit thin as time goes by, like after the first half hour. And probably by the time you reach India, you are so sick a tired of the honking that you are ready not to hear another honk for the next… six months, I suppose, until it is time to fly back to Mongolia. Probably just as well I am not a goose. If I were, I would be one very grumpy goose, or easily recognizable by the fact that I am the odd one out in the flock, wearing a pair of big Sennheiser noise-cancelling headphones.
In fact the honking reminds me a bit of people you see jogging and chatting all the while. Make up you minds! Run or chat! Both, simultaneously, just seems like a weird combination.
So, I reckon bar headed geese could also profit greatly from my Cacophony Bonnet™ (pat. pending) I developed with Owls in mind, to save them all that twit-wooing, but of course it would work equally well for Himalaya-defying geese.
Never let it be said that I do not have an open mind!