NESTBOX TROUBLESHOOTING CHART

by Don Wills

PROBLEM	CAUSE	OPTIONS FOR SOLUTION

Box filled with domed nest, adults or nestlings dead with heads pecked	House Sparrow	Don’t put bluebird boxes in house sparrow habitat Remove sparrow nest and trap male with in-box trap. Move box to a more suitable location at least 1/2 mile from livestock barns.

Feathers and white eggs on top of bluebird nest	Tree Swallow	Twin existing box with another box located 10-25 feet away.

Box filled with twigs, eggs thrown out of box or speared	House Wren	Locate boxes at least 150 ft from wooded or brushy habitat. Hang boxes from tree branches or twin with smaller design box.

Straw nest with large blue eggs	European Starling	Clean out nest, make sure entrance hole hasn't been enlarged by woodpeckers. Repair entrance hole with aluminum or steel plate.

Eggs or young gone Nest material pulled out of entrance. Scratch marks around entrance	Raccoon	Mount all boxes on smooth steel posts, plastered with grease or use predator guard.

Eggs or young missing, nest material disturbed, feathers on ground	Domestic Cat	Mount box on predator proof steel pole with lots of grease or steel cone shaped predator guard. Keep box at least 6 ft above ground.

Young dead with head missing or mutilated	Weasels	Keep box in open area away from rock piles or fence rows. Mount box at least 6 ft high with predator proof post.

Box full of loose plant fibres containing seeds and usually having a strong smell.	Deer Mice	Carefully remove nest remembering that deer mice nests could contain Hanta Virus in the dust. Make sure box is mounted on steel post with predator guard or grease.

Adult bluebirds reluctant to go in box.	Wasps or Yellow Jacket Nest	Apply soap to the underside of the roof. Carefully remove paper nest or set out another box nearby.

Nest full of ants usually found under nest.	Ants looking for dry area for eggs	Remove nest or if the box contains eggs or young add new grease along the entire steel pipe. Ants wont go through grease. The ones left in box should not bother the young birds.

Nestlings with white larvae attached to legs or elbows, black pupae or gray maggots under nest	Blowfly	Raise nest carefully with a flat tool and sweep out the maggots. Tap the bottom of the nest to remove any still in the grass. It takes more than a hundred maggots per box to cause damage to the young.

Nestlings dead or chilled in wet nest.	Rain in Box; Wet adults have entered box. Nestlings abandoned	Face entrance hole away from east winds. Make sure box is tightly constructed with proper overhang Plug ventilation holes, replace wet nest material with dry grass. Remove dead young or foster orphans if possible.

Adult dead in nest for no apparent reason	Injury from vehicle collision; pesticide poisoning	If box is near road, turn entrance to face away from road. Never put up boxes in an area that is heavily sprayed with insecticides.

Both parents disappear	Been killed	If you keep accurate records and have many other pairs, the nestlings can be fostered successfully Never add more young to a box than the adults can handle. If no nests are available, arrange to have them delivered to a rehab centre or look to other bluebird trails in your area. The young must be kept warm and fed with mealworms until arrangements are made.