Ants sometimes "infest" nests in boxes. Fire Ants can be a serious problem, as they will kill and eat nestlings. Other ant species may not harm eggs/young, but may pester them by crawling on their bodies.
To control crawling insects after the first egg is laid, try:
Remove old nests immediately after babies fledge, as detritus and feces may attract ants.
Some monitors remove unhatched eggs - if they break, they might attract ants. (Always wait at least 72 hours after first nestling hatches before removing an egg. Some birds like chickadees often remove them themselves.)
I'm not sure what species these are - I call these "sugar ants." They are unlikely to harm nestbox contents, but may swarm all over the box and your hand when disturbed. Click here for higher resolution photo. I occasionally find them in nests in CT.
Tanglefoot - USE WITH CAUTION! FOLLOW INSTRUCTIONS CAREFULLY! Wrap green garden tape around
the mounting pole, right under the box, or UNDER the baffle and then apply the Tanglefoot
to the tape (put tape on tightly so ants can't crawl under it). When the Tanglefoot loses its effectiveness, just
cut the green tape off and remove it. Be careful not to put it where a bird could come into contact with it as it is sticky and will be almost impossible to remove from the bird! If you get
it on your clothing a solvent (e.g., GO-JO cream available at Sam's, or Citra-Solv) will remove
it. It may be available at a feed store, nursery, or some hardware
stores such as Ace, True Value or Aubuchon, or can be purchased online. (If Tanglefoot does get on a bird, call a rehabber or use mineral oil to dilute the tanglefoot. Then use soap (Dawn liquid detergent) and WARM water. Around the eyes do the same but with a Q-tip. Rinse thoroughly)
Dip Q-tips in an ant repellant called "Terro" and staple them to the outside bottom of the box, and tape a few to the pole.
Greasing (automotive or all purpose) poles is okay, but when the temperatures get hot the grease may run, whereas Tanglefoot will not. Vaseline or a mixture of turpentine and lithium grease may be painted in a 4" wide ring around the mounting pole (directly under the nestbox, or if there is one, under the baffle, to prevent blue feathers from coming into contact.) It will harden in the sun, so reapply twice during nesting season.
Place a small moat around the bottom of the mounting pole (e.g., put a "Bundt" style baking pan down over the pole and fill with water.)
Herbal deterrents: (effectiveness?) put a small amount of crushed sage or crushed peppermint leaves under the nest.
