Why is my ghost shrimp yellow?

I have had this ghost shrimp for about a month and noticed he turned yellow. Does anyone know why this is?

Just blending in with its surroundings. They also go darker in colour if they are kept in water that is stained with tannins.

The only time to worry about the colour of shrimp is if that start turning a milky white in the body. This is a microsporidian or spironucleus infection (can't remember which one), but they can both be treated with salt if you catch it early.