Birds on the Western Front

Question

I don't understand what this paragraph is saying:
The partridge of the war zone shows no signs of such sensitive nerves. The rattle and rumble of transport, the constant coming and going of bodies of troops, the incessant rattle of musketry and deafening explosions of artillery, the night-long flare and flicker of star-shells, have not sufficed to scare the local birds away from their chosen feeding rounds, and to all appearances they have not been deterred from raising their broods. Gamekeepers who are serving with the colours might seize the opportunity to indulge in a little useful nature study.

Answer 1

Partridge is a type of gamebird which you've probably heard in the popular holiday song "12 Days of Christmas". When the author says, "The partridge" he is referring to the birds that can be found around the war zone. The next sentence describes the action of the war zone, the loud noises and busy traffic of the location, and concludes that the birds must not be afraid of the heavy foot traffic and noises because they continue to eat and raise their young there. "Gamekeepers who are serving with the colours" most likely refers to soldiers serving their country ("the colours" representing the colors on a country's flag) and the sentence is stating that because there are birds around the war zone the soldiers can enjoy a bit of nature.