August 6, 1918 – Full diary entry:

“Rain and cold. On guard in trenches all night. Mud + Rats. Fired about 100 rounds. We expected a raid but were disappointed.”

Rats in the trenches? You bet there were. Here’s our old friend Chaplain Edwards in From Doniphan to Verdun:

The rats were numerous and at first the men found it difficult to sleep. Some of the men claimed to have rats with service stripes and wound chevrons. They gave them names and managed to find a good deal of amusement; the strength of the American Army is partly due to that spirit which can find fun in any situation and make a joke out of any difficulty. It was here that the boys invented the trench rat trap. A piece of bread would be placed on the end of a bayonet and the rifle held across the parapet. Pretty soon a rat would come along and nibble at the bait. A trigger pull and the rat was gone.

Some more detail from Spartacus Educational (note: this article is NOT for the faint of heart):

Many men killed in the trenches were buried almost where they fell. If a trench subsided, or new trenches or dugouts were needed, large numbers of decomposing bodies would be found just below the surface. These corpses, as well as the food scraps that littered the trenches, attracted rats. One pair of rats can produce 880 offspring in a year and so the trenches were soon swarming with them.

Where was Robert today? See the timeline.