You can easily find yellow bulbs online or at your local hardware store. Look for a "bug light" label, or for a warmer color temperature (around 2000 Kelvin).

Light bulbs on the market will range from about 2000K to 6500K, which will appear yellow to white to blue as you move higher on the scale. Candlelight is equivalent to about 2000K and will have a ...

In the morning, they switched off the bulb and looked in the trap to see what it had caught. Over the summer, 8887 bugs fell prey to the light, but some lights pulled in more than their share.