Tree Swallow (Tachycineta bicolor)
The tree swallow is the only swallow described in this section that does not breed in Europe. The breeding range of this bird that closely resembles the common house martin is restricted to all of Canada south of the northern tree limit and parts of the USA (north of the line from southern California to Virginia crossing western Colorado, northeastern Kansas and Louisiana). It winters in Central America (including Mexico), Cuba and parts of the southern USA.
When not breeding it is a very sociable bird that lives and migrates in large flocks. In December of 2009 a flock that was estimated at one million birds - a very large flock indeed - was observed in the vicinity of Vacherie, Louisiana, USA.
My Flight Muscles *
Do you have any idea why we birds are able to fly? It is not as easy as you might think. Our entire organism had to be specially designed for flight by our Creator. It’s not enough just to have feathers. We can move our wings up and down without effort. Most four-legged animals, on the contrary, move one foot forward, then another. You do the same thing with your arms, without thinking about it, when you walk. Of course, it’s a small thing. But without this instinctive moving of both sides at once, I couldn’t fly a single metre. Furthermore, we have to move our “fore-feet” (i.e. our wings) back and forth faster than any other animal. The record is held by our smallest colleague, the tiny, 3-centimetre tall hummingbird. He is able to flap his wings 80 times per second. If you had the same ratio of strength to weight that he has, you would be able to throw 56 sacks of cement higher than one metre into the air – every second. So you see, flying requires a lot of strength. That means our flight muscles – in relation to our body weight – are among the strongest muscles in the animal kingdom. They make up one-third of our body weight.
Scientists have discovered that an eagle produces a constant energy equivalent of one-tenth of a kilowatt. I admit that I can’t do that. But I am a lot smaller. Just think what the energy producing capacity of a human is. It’s no more than that of the average eagle. With such a pitiful energy capacity, you wouldn’t be able to handle even gliding for one minute, let alone any kind of powered flight.
The swallow continues its story: My feathers
* quotes from the book "If Animals Could Talk"
