Quoting Delores Wendt, an active member of Bluebird Restoration of Wisconsin, “The most important part of a bluebird program is to put up bluebird houses and monitor them. If you feel that you don’t have time to monitor them, I suggest that you don’t put them up, and I repeat, don’t put up unmonitored bluebird houses.” That may sound a bit harsh to many bluebirders out there, but it is very sound advice. There are many different statewide bluebird organizations across the country and they all stress that same point. Bluebird boxes must be monitored on a regular basis. So, in turn, Bluebirds Across Nebraska has also adopted this policy and will stress the importance of trail monitoring.
Many people put up bluebird houses with only the best intention of doing the right thing for the bluebirds. But for numerous reasons, after time, the houses are very seldom checked or are totally abandoned. Putting up bluebird houses is a commitment to increasing the bluebird population. The privilege of helping a wildlife species doe not normally fall on the average citizen. This endeavor usually falls upon wildlife managers or professional biologists such as those working with the peregrin falcon and bald eagle projects, etc.
The only way to achieve the goal of Bluebirds Across Nebraska, which is to increase the bluebird population in Nebraska, is to enroll as many people as possible across the state to join in out efforts by putting up bluebird houses and properly monitoring them. There are many reasons for monitoring bluebirds boxes. Listed below are ten of the most important reasons for monitoring bluebird boxes on a regular basis.
- Initial Checking Of Boxes In Early Spring; Necessary Relocations–Remove all mice nests if boxes have not been left open. Clean boxes thoroughly and make, necessary repairs. Relocate any boxes in high predation areas or in areas encroached by wren habitat. Where pesticide use is anticipated later in the season, boxes should also be moved to a safe location. (Pesticide use is more of a problem in during bluebirds’ second nestings).
- Removal Of Wasps, Wasp Nests, Ants, And Gnats– Bluebirds will not nest in a box occupied by wasps. Ants or gnats swarming over un-weathered nestlings can cause death. Ants, gnats, and wasps can be taken care of with a pyrethrin based product. Pyrethrin-based products are the only products recommended for use in boxes. A band of grease around the mounting pole will stop ants from reaching the box.
- Blowfly Larvae– Blowfly larvae can easily be checked if boxes are monitored on a weekly basis. In a time frame as short as seven days, what is a mild infestation can become severe if not taken care of. Blowfly larvae can kill nestlings. If a few larvae are found, lifting up the nest and gently shaking it may dislodge the larvae and they can be brushed out. If the infestation is more severe, the larvae can be treated with a pyrethrin-based product.
- Wet Nests– A wet nest can be deadly to nestlings and is more likely to happen in early spring when temperatures are cooler (the first nesting attempts). Top-opening boxes, leaky roofs, and clogged drainage holes can all lead to moisture and water accumulation in nesting boxes. This, in turn, leads to hypothermia in the nestlings. When checking a box, it is important to check the nest itself and not just the nestlings. It the weather is cool and a wet nest is found, a wet nest can be replaced. The nestlings can be removed with great care, placed in cloth in a box, and a new cup shaped nest made out of dry grass can be made to replace the old one.
- Abandoned Nestlings– On rare occasions when both parents are killed, you might find abandoned nestlings. A nestling can be considered abandoned when they have not been fed for a period of four daylight hours. It is usually impractical to observe the nesting box from a distance for four hours, so something such as a piece of thread, a leaf, a tiny stick, or a piece of paper can be placed off to the side in the box entrance hole. The parents can then push it out of the way to feed the nestlings, which will let you know if the nestlings have been abandoned or not. If you determine that the nest is abandoned, distribution of the nestlings can be made to other boxes. Be careful to match the nestling age with those in the “new’ nest and be sure not to have over six nestlings in one box. Never try to hand raise a nestling. This must be done by a licensed rehabilitator. If further advice is needed, contact a BAN representative.
- Sparrows– Boxes that are placed too close to buildings and in areas where animals and poultry are fed are very susceptible to house sparrows. Boxes placed in such areas and not monitored definitely have an adverse effect on bluebirds because house sparrows using the nesting boxes may have as many as four or five broods a season. Also, bluebirds that nest in areas with a high sparrow presence are vulnerable to sparrow attacks, commonly killing the adult bluebird in the box and destroying eggs and nestlings. Boxes placed in areas heavily used by sparrows should be moved or a sparrow trapping program should be started.
- Wrens Usurpation– The wren is quickly taking over the sparrow’s long-held title as “the bluebirds worst enemy.” Wrens can pierce or carry out bluebird eggs and will sometimes kill young nestlings. Not that long ago, a box placed 50 feet from cover (brush or trees) was generally safe from wrens. Now, because of the over population of wrens on bluebird trails, 200 feet is considered the “safe’ distance. To avoid this growing problem, place your boxes away from wren habitat whenever possible. (Bluebirds’ first nesting attempts are usually safe from wrens as the wrens arrive later in the spring.)
- Raccoons, Cats, And Snakes– Ideally, a box should be mounted in a manner that denies raccoons access to it. Once a raccoon discovers he can get into a box or a series of boxes on a trail, it will raid them on a regular basis and your trail will become a predator highway. Mounting poles can be greased or coated with silicone spray. This will greatly deter raccoons and snakes. Snake guards can also be placed on the pole. Cats also pose a great threat. A Noel predator guard is very effective for keeping both raccoons and cats out of boxes. Cats can easily snare an adult bluebird while it is attempting to reach the box or fledglings after they have left the nesting box.
- Removal Of Old Nests– It is very important to remove the nest as soon as the nestlings have fledged, making it available for other nesting attempts. It is also important to thoroughly clean out the box after each nesting.
- Self Gratification– The warm and rewarding feeling of regularly checking the bluebirds through their nesting cycle should be reason enough for monitoring your trail. Bluebirds are one of the few birds that readily accept human help and continuous observation. Walking your trail shouldn’t be considered work, but a privilege. It is rewarding to know that you are really making a difference.
Special Note–Boxes should not be checked during cold or rainy weather. Nestlings need the warmth kept in the nest during inclement weather.
- Bluebird Trails, A Guide to Success by Doreen Scriven
- Bluebird Restoration Association of Wisconsin, for information used in writing this article.
This information has been provided to you by Bluebirds Across Nebraska. Be a part of the conservation solution. Join BAN. Write to P. 0. Box 67157, Lincoln, Nebraska 68506-7157.