Sparrow Spookers: Designs & Instructions

A ready-made, weather-resistant Sparrow Spooker is now commercially available from Sparrowtraps.net. This spooker is readily mounted on any style box. The height and spread of the “V” shape are adjustable. it comes with two mounting brackets so you pop it on the box that is “chosen” as soon as the first egg is laid. It comes with a roll of Mylar tape that you can cut to size and clip on the horizontal bars. Bluebird landlords were involved in its design. To keep it from spinning, put a little duct tape around the rod where it goes through the white holder.

Photos courtesy of Sparrowtraps.net.

• One vertical piece about 12″ long. Vertical piece can be made from a yardstick, dowel, black plumbing hose, or a piece of plastic pipe.
• One to three horizontal pieces that are as long as the roof. The same materials can be used for horizontal pieces. Chopsticks (from Chinese restaurants) also work well.
• Strips of flexible, reflective material – ideally mylar. (not transparent or translucent).
  • Strips are often 1/2″ x 6″. If you’re not sure how long they will need to be once the spooker is installed, leave them long and cut them with scissors after installation. If the strips are too long, they may not hold up under windy conditions.
    • Buy a roll of Bird Repellent Scare Tape Holographic Bird Scare Ribbon, Double Side Bird Deterrent
    • Buy mylar (shiny, silvery material) signs (e.g., Happy Birthday banners) from a party supply/Dollar Store/Wal-Mart. (Pieces of mylar balloons tend to curl up. The mylar used in banners is thicker, you can make the strips as long as needed, and there is less waste.)
    • A Coleman Emergency Blanket (from Wal-Mart or Target) is also made of mylar, and only costs several dollars.
    • C. Layton made two years’ worth of strips from one blue foil bag that Wal-Mart potato chips come in (after the chips were consumed:-).
    • Aluminum foil does not work as well (doesn’t flap, falls off), but can be used in a pinch, as can tree flagging material, which does not last.
  • The strips may be attached to the horizontal piece with a glue gun, duct tape, or staples. Lately I’ve been using a long piece of duct tape folded over the horizontal dowels as shown in the temporary spooker above (don’t leave anything sticky out that a perching bird might get stuck to.)
• A means to attach the device to the nestbox – e.g., screw, hose clamp, duct tape, cable tie, etc.
  

Instructions for making a sparrow spooker:

1. Drill hole(s) the diameter of the horizontal pieces into the vertical piece of wood (or a 1″ piece of waste drain hose – fits well if box is mounted on a metal conduit pipe).
   • Design #1 diagram uses two dowels in a “T” configuration. In Design #2, the dowels stick out over the nestbox roof in the shape of a “V,” and extend to the front edge of the roof. The original Design #3 uses a vertical piece only.
   • Design#4 relies on an “L” shaped plastic plumber’s elbow to connect horizontal and vertical pieces.
   • Whatever you use, it shouldn’t be too heavy.
2. Glue the dowels into the wood strip for Designs #1 and 2. Don’t use wood that is too heavy.
3. Attach the Mylar strips at even intervals to the horizontal pieces (3 or 4 per dowel) so they hang down loosely over the roof, just brushing the roof. If the strips are too long and hang over the entrance hole, the bluebirds may not like it, although some folks use that set up.
   • If you’re not sure how long to make them, cut them extra long and then after mounting the spooker on the box, trim so they just brush the roof.
   • Try a staple gun for attaching.
   • If you use duct tape, it may deteriorate in rain. You can lay the duct tape out lengthwise, draping it over the horizontal piece, and then sealing it to itself. Be sure no sticky parts are exposed as birds may perch on it.
   • If you use hot glue, it may melt in the sun, so put the glue on the inside where the mylar touches the dowel, or also use duct tape for added adherence.
   • Another option (shown in Design #1) is to drill holes in the vertical pieces, and then pull the mylar through the hole and knot it.
4. Mount the sparrow spooker to the back of the bluebird house so that there is a distance of about 8″ between the roof line and the top of the device. This will allow the mylar strips to blow freely in the wind. The strips should almost touch the roof of the house. In order to avoid addling eggs, do not shake the box during installation (e.g., avoid drilling or remove nest during drilling.) Be careful not to split a wooden roof when you attach a screw (pre-drilling is a good idea here but see note above.) Connection options include:
   • a hose clamp on the pole if it sticks up above the roof, for easy removal after fledging
   • as shown in Design #1
   • with locking cable ties as shown in Design #4)
   • If the spooker wants to fall over, you can put a nail/screw on either side of it to hold it upright, or use two screws one over the other.
5. If you have a bluebird trail in a public location, you might want to thumbtack a little laminated tag onto the side of nestboxes with Sparrow Spookers installed, to explain to interested public what the mylar device is.  It might encourage them to try one out. (Thanks to Paula Ziebarth for this idea.)

Acceptance by Bluebirds: Different species and different individuals of the same species behave different, and may react differently to anything noticeably new. By putting the spooker up after the first egg is laid (egg laying typically occurs in early morning, before 1 p.m.), you will have confirmation of acceptance (and will not have to worry about interrupting incubation), as long as a new egg is laid the next day. You will also be protecting the nest while it is unoccupied, since the female does not begin incubating the eggs until she finishes laying all her eggs.

If desired, observe the box after installation. In my experience, the female usually accepts it almost immediately–it may take the male 10-30 minutes. Males have been seen grabbing the end of a piece of mylar and shaking it or pulling on it right after installation.

It would be unusual for a spooker not to be accepted within an hour or two. (I have heard of one instance where it was NOT accepted by the female, and she only returned to the box after the spooker was removed. That is why observation is useful.)

Avoid installing the spooker when it is very windy, as this may affect acceptance. If they don’t seem to accept it right away, leave the spooker up but take a rubber band and bunch the streamers to the top post out of the way. Then let one or more of the streamers down every day to desensitize them.

Can I put the spooker up before an egg is laid? Some people have so many problems with House Sparrows that they want to put a spooker up BEFORE an egg is laid. I do not really recommend it for these reasons:

1. HOSP could become accustomed to it, and this very useful tool could lose its effectiveness! You might end up training HOSP to overcome their fear of the best HOSP deterrent there is so far. (I heard at least one report where a spooker was put up during nestbuilding and a pair of HOSP did overcome their fear of it.)
2. It could possibly deter bluebirds (or other native birds) from using the box, since they are not as committed as they are when they have laid an egg.

Instead, I recommend monofilament (which reduces HOSP interest in a box if put up before the male ‘bonds’ with the box) and other methods (passive and active) in the interim.

One person did report putting sparrow spookers on two nestboxes early – one during bluebird nest building (before egg was laid), and one before Tree Swallows occupied a box (the previous swallow occupant was killed by HOSP). In both cases, the bluebirds and Tree Swallows did accept the “early” spooker and went on to successfully nest. More data is needed on this practice. Another person left one up after fledging, and the bluebirds went on to build a second nest. However, see concerns above.

We really do not know why the spooker or the magic halo deter HOSP and not other birds. Perhaps as seed eaters, their vision is not as good as birds that are predominantly insect eaters. When placed on a mealworm feeder, a spooker was not accepted by blues. A Magic Halo is a better choice for a FEEDER – it is NOT intended for use on a nestbox.

If the spooker is on a box in a public place, you might want to thumbtack or staple a laminated message to the box for educational purposes: “The mylar “sparrow spooker” above this box is meant to keep nonnative House Sparrows from killing the Tree Swallow adults/eggs/nestlings that occupy this nest box.”

Failures: I have heard of the following instances of spookers failing:

• One with Design #3
• One where non-iridescent material was used
• One with unknown design
• One with Design #2, after the male bluebird disappeared. Failure may have been associated with particularly aggressive male HOSP, and mylar curling up and thus not extending or fluttering properly.
• One with a standard, recommended design – a female HOSP entered the box on several occasions (but did not harm nestlings)
• Two with standard design, while HOSP nests and eggs were being removed in neighboring boxes. See discussion of HOSP revenge syndrome. Instead of removing nests and eggs, addle the HOSP eggs so they are nonviable and return them to the nest. (This will not help with single males.) The safest, most effective solution is to trap both the male and the female to completely eliminate the possibility of an attack.
• One where the spooker was not removed between first and second nestings, and the strands deteriorated and no longer brushed the nestbox roof.

A Spring 1995 issue of Sialia contained a report that Wayne Davis and Beth Blankenship experimented with four streamers made of plastic flagging, hung from the front of the roof of slot boxes. With this set up, the bird would have to go in between the flagging to enter the box. No deterrent effect was observed either on bluebirds or HOSP.

Acceptance by Other Species:

• Note that Sparrow Spookers do NOT deter House Wrens, which may also peck and remove eggs and very young nestlings. See more info on deterring House Wrens.Several people have had Tree Swallows accept Design #1 and #4. They may balk. I tried Design #2 on a pair of TRES in CT and it was not accepted after 15 minutes so I removed it (it was very windy when I tried). See recommendation on wind. Little information is available about acceptance of sparrow spookers by other cavity-nesters, or pre-egg laying.
• One person reported successfully using a sparrow spooker on an active bluebird nest to deter mobbing Tree Swallows trying to take over the nestbox.
• It would be reasonable to expect that titmice and chickadees, which are more sensitive to monitoring, might take issue to a spooker. Anne-Marie Palermino succesfully used a spooker on a chickadee nest, although hole restrictor (smaller than 1.25″ diameter) may be a better choice for these birds.
• Claudia Daigle successfully used one on a House Finch nest.
• Pam Stenner used a variation on an Ash Throated Flycatcher nest. She said “they are so secretive and shy that I wasn’t sure how they would take to a spooker. So I put up a spooker “frame” –a piece of wood that I could hang the mylar streamers from, before they even started building a nest. After they had laid a couple of eggs, I hung just one mylar streamer far away from the entrance hole. When they were okay with that, I added more one at a time–each one closer to the entrance hole.” They accepted it.

A sparrow spooker is an invaluable tool to protect nesting bluebirds. However, nothing besides trapping and elimination is foolproof. To effectively manage HOSPs, I recommend using a combination of passive and active control techniques.

Sources and Acknowledgements:

• House Sparrow Deterrent from NABS and Gwen Newton-Denton. Note: I have a copy of the Spring 1985 edition of Sialia, the quarterly NABS journal, and could not find the drawing above in it.
• Posts on the Bluebirding Forum
• Posts on the Bluebird Nut Cafe – see http://www.bluebirdnut.com/Competitors.htm#spooker
• Drawings by Yvonne Domings and E.A. Zimmerman.
• Photos by Pam of NJ, Cher Layton and E.A. Zimmerman.
• Sparrowtraps.net Sparrow Spooker
• Dalen HST100 3/4-Inch by 100-Foot Holographic Bird Scare Tape