The sound of bird chatter is music to a nature lover's ears, and it's always a happy sight to see birds swooping into the garden to nab caterpillars and other insects. Yet our wild bird friends can turn into foes when they start pecking up seedlings or stealing berries. When it comes to birds in the summer garden, sometimes you must step in and show them who's boss.
First, there are some bird control methods that just don't work. Hot pepper sprays are widely recommended to as a bird repellent, despite the fact that 30 years of research has shown that birds lack sensory receptors for capsaicin, the active principal in hot peppers. Mammals such as squirrels, rabbits or dogs can be deterred with hot pepper brews, but not birds. A fundamental weakness also makes ultrasonic devices worthless for bird control: birds cannot perceive ultrasonic sounds any better than we can. Garlic oil falls into a marginal category. In a New York study, European starlings fed bird seed scented with garlic oil reduced their food intake and started looking for a less aromatic food supplies, but who wants strawberries that smell like garlic?
Bird Netting and Other Barriers
There is no question that the most effective way to control birds feeding on blueberries, raspberries and other high value fruits is to cover them with some type of net barrier. Products sold as bird netting will keep out birds, but I had two problems with it – the netting snares easily on thorny bramble fruits, and hummingbirds sometimes became entangled in it. Neither of these issues are relevant if you attach the netting to a rigid frame, so that it forms an enclosure around plants that is tight on all sides, but building a walk-in berry cage that will hold up to wind and weather is a complicated project. As an alternative, you can try lengths of voile or wedding net (tulle) fabric, draped over plants and fastened with clothespins. For temporary protection of ripening berries, these featherweight fabrics are hard to beat.
Of course, not all fruits are at risk. Birds on all continents recognise cherries and strawberries, but in the US non-native red raspberries are not fed upon as heavily as native black raspberries and blueberries, which wild birds have been eating for aeons. In the UK, birds can't get enough blueberries and redcurrants, but seldom touch golden raspberries or gooseberries.
Scaring Away Hungry Birds
Crops that are only moderately attractive to birds often can be protected with various scare devices, keeping in mind that you might need a variety of methods. When Dutch researchers surveyed bird control methods at six large airports around the world, they found that the best bird control was achieved by watching the birds closely and changing scare tactics when they stopped being effective.
In large spaces like airports or farm fields, persistent birds like blackbirds and starlings scatter when they think they see a gigantic hawk hanging over the field. In the UK, the aptly-named Terror Hawk and Terror Kite convince birds to move on as they dance from 7 m (20 ft) poles, as can the Helikite, which stays airborne with the help of a helium-filled balloon.
But in a small garden, you can try cheap and easy bird control solutions like trimming fruit trees or berry bushes with pieces of reflective tape, small wind chimes that make noise and have metallic surfaces that reflect light, or old CDs or little mirrors. Blackbirds in particular seem wary of bright yellow anything, including plastic streamers. Some people tie plastic grocery bags around the outer edges of their gardens to deter birds and other pests, but flash tape and mirrors are much prettier.
Most of these low-grade bird repellents will work for a week or two, and then you must change to something else. Small stuffed animals mounted on posts near ripening berries can be a fun rotation on the bird control front, and scarecrows can deter birds for a month if you reposition his or her hat and clothes and move it about from time to time. This is easiest to do if the scarecrow starts its life in a lawn chair that can be easily picked up and moved.
You can also use mean-looking scare-eye balloons, or even make one from a beach ball. As long as the object is strange, quivers or moves, and is bright yellow and bears circle-in-a-circle markings that look like the open mouth of a hawk, it will deter birds.
Personally I don't want to have such hostile-looking objects in my garden, so I'll stick with netting, shiny things, and an occasional scarecrow to establish peaceful coexistence with the wild birds that come after my crops. When the weather is kind and I attend to the garden with care, there is enough to share and we are all well fed and happy.
By Barbara Pleasant