Part 2

Many people want martins in their yards because, it’s been said, these birds eat 2,000 mosquitoes a day. While it’s true that they eat flying insects, don’t expect purple martins to eliminate mosquitoes in your yard completely. Martins prefer dragonflies, which prey on mosquito larvae. If you want to help rid your yard of mosquitoes, put up a bat roosting box. One bat can eat thousands of mosquitoes a night.

Martins are entertaining creatures, however, and you’ll enjoy watching their antics in your backyard. You have the best chance of attracting martins if you put a house on the edge of a pond or river, surrounded by a field or lawn. Martins need a radius of about 40 feet of unobstructed flying space around their houses. A telephone wire nearby gives them a place to perch in sociable groups.

Martins nest in groups, so you’ll need a house with a minimum of four large rooms—6 or more inches on all sides, with a 2½ inch entrance hole about 1½ inches above the floor. Ventilation and drainage are critical factors in martin house design. Porches, railings, porch dividers and supplemental roof perches, like a TV antenna, make any house more appealing.

You can also make houses from gourds by fashioning an entrance hole and small holes in the bottom for drainage. If you use gourds, it’s not necessary to add railings and perches. Adult martins will perch on the wire used to hang the houses. Before you select a house, think about what kind of pole you’re going to put it on. Martins occupy a house ten to twenty feet off the ground. Some poles are less cumbersome than others.

Gourd houses are the easiest to set up. String them from a wire between two poles, from a sectional aluminum pole, or on pulleys mounted to a crossbar high up on a pole.

You can mount lightweight aluminum houses for martins on telescoping poles, providing easy access for maintenance and inspection. Because of their weight (more than 30 pounds), wood houses should not be mounted on telescoping poles. You’ll have to use a sturdy metal or a wood pole attached to a pivot post. The problem with this lowering technique is that you can’t tilt the house without damaging the nests inside. If you put your house on a shorter, fixed pole, ten to twelve feet high, you can use a ladder to inspect and maintain it.

_Flycatchers_

The great crested flycatcher and its western cousin, the ash-throated flycatcher, are common in wooded suburbs and rural areas with woodlots. Their natural nesting sites are abandoned woodpecker holes. Flycatchers may nest in a bird house if it is placed about ten feet up in a tree in an orchard or at the edge of a field or stream. This is a longshot, but well worth the effort if you are successful.

_Woodpeckers_

You can attract all types of woodpeckers with a suet feeder, but only the flicker is likely to use a bird house. They prefer a box with roughened interior and a floor covered with a two-inch layer of wood chips or coarse sawdust. Flickers are especially attracted to nest boxes filled with sawdust, which they “excavate” to suit themselves. For best results, place the box high up on a tree trunk, exposed to direct sunlight.

Try building a birdhouse for the other species of woodpeckers following the guidelines in this booklet. You might be surprised!

_Owls_

Most owls seldom build their own nests. Great horned and long-eared owls prefer abandoned crow and hawk nests. Other owls (barred, barn, saw-whet, boreal and screech) nest in tree cavities and bird houses.

Barn owls are best known for selecting nesting sites near farms. Where trees are sparse, these birds will nest in church steeples, silos and barns. If you live near a farm or a golf course, try fastening a nest box for owls about 15 feet up on a tree trunk.

Screech owls prefer abandoned woodpecker holes at the edge of a field or neglected orchard. They will readily take to boxes lined with an inch or two of wood shavings. If you clean the box out in late spring after the young owls have fledged, you may attract a second tenant—a kestrel. Trees isolated from larger tracts of woods have less chance of squirrels taking over the box.

Selecting a House

In the bird house business, there’s no such thing as “one size fits all.” Decide which bird you want to attract, then get a house for that particular bird. Look through any book or catalog and you’ll see bird houses of all sizes and shapes, with perches and without, made of materials you might not have thought of: recycled paper, gourds, plastic, rubber, pottery, metal and concrete. The proper combination of quality materials and design makes a good birdhouse.

Materials

Wood is just about the best building material for any birdhouse. It’s durable, has good insulating qualities and breathes. Three-quarter-inch thick bald cypress and red cedar are recommended. Pine and exterior grade plywood will do, but they are not as durable.

It makes no difference whether the wood is slab, rough-cut or finished, as long as the inside has not been treated with stains or preservatives. Fumes from the chemicals could harm the birds.

There’s no need to paint cypress and cedar, but pine and plywood houses will last longer with a coat of water-based exterior latex paint. White is the color for purple martin houses. Tan, gray or dull green works best for the other cavity nesting species. The dull, light colors reflect heat and are less conspicuous to predators. Don’t paint the inside of the box or the entrance hole.

Regardless of which wood you select, gluing all the joints before you nail them will extend the life of your bird house. Galvanized or brass shank nails, hinges and screws resist rusting and hold boxes together more tightly as they age.

Resist the temptation to put a metal roof on your bird house. Reflective metal makes sense for martin houses up on a sixteen-foot pole, but when it’s tacked onto the roof of a wood chickadee house, the shiny metal is more likely to attract predators.

Natural gourds make very attractive bird houses. They breathe, and because they sway in the wind they are less likely to be taken over by house sparrows and starlings.

Grow your own gourds and you’ll have dozens to choose from in the years ahead. If you don’t have the space to grow them, a coat of polyurethane or exterior latex (on the outside only) will add years to the one you have.

Properly designed pottery, aluminum (for purple martins only), concrete and plastic houses are durable, but don’t drop them.

Be sure to provide ventilation, drainage, and easy access for maintenance and monitoring. Concrete (or a mix of concrete and sawdust) offers protection other houses cannot: squirrels can’t chew their way in.

Design

How elaborate you make your bird house depends on your own tastes. In addition to where you place the box, the most important considerations are: box height, depth, floor dimensions, diameter of entrance hole and height of the hole above the box floor.

Refer to the following chart before building your nest box, keeping in mind that birds make their own choices, without regard for charts. So don’t be surprised if you find tenants you never expected in a house you intended for someone else.

Nest Box Dimensions

Species Box floor Box Entrance Entrance Placement (inches) height height (inches) diameter (inches) (inches) height (feet)

American Robin[1] 7×8 8 —— —— Eastern & Western 5×5 8-12 6-10 1½ 4-6 Bluebirds Mountain Bluebird 5×5 8-12 6-10 1½ 4-6 Chickadee 4×4 8-10 6-8 1⅛ 4-15 Titmouse 4×4 10-12 6-10 1¼ 5-15 Ash-throated Flycatcher 6×6 8-12 6-10 1½ 5-15 Great Crested Flycatcher 6×6 8-12 6-10 1¾ 5-15 Phoebe[1] 6×6 6 —— —— 8-12 Brown-headed/Pygmy/ 4×4 8-10 6-8 1¼ 5-15 Red-breasted Nuthatch White-breasted Nuthatch 4×4 8-10 6-8 1⅜ 5-15 Prothonotary Warbler 5×5 6 4-5 1⅛ 4-8 Barn Swallow[1] 6×6 6 —— —— 8-12 Purple Martin 6×6 6 1-2 2¼ 6-20 Tree and Violet-Green 5×5 6-8 4-6 1½ 5-15 Swallows Downy Woodpecker 4×4 8-10 6-8 1¼ 5-15 Hairy Woodpecker 6×6 12-15 9-12 1½ 8-20 Lewis’s Woodpecker 7×7 16-18 14-16 2½ 12-20 Northern Flicker 7×7 16-18 14-16 2½ 6-20 Pileated Woodpecker 8×8 16-24 12-20 3×4 15-25 Red-Headed Woodpecker 6×6 12-15 9-12 2 10-20 Yellow-bellied Sapsucker 5×5 12-15 9-12 1½ 10-20 Bewick’s/House Wrens 4×4 6-8 4-6 1¼ 5-10 Carolina Wren 4×4 6-8 4-6 1½ 5-10 Barn Owl 10×18 15-18 4 6 12-18 Screech-Owl and Kestrel 8×8 12-15 9-12 3 10-30 Osprey 48×48 platform Red-tailed Hawk/Great 24×24 platform Horned Owl Wood Duck 10×18 10-24 12-16 4 10-20

[1]_Use nesting shelf, platform with three sides and an open front_

Now that you have the correct dimensions for your bird house, take a look at how to make it safe: ventilation, drainage, susceptibility to predators, and ease of maintenance.

_Ventilation_

You should provide air vents in bird boxes. There are two ways to provide ventilation: leave gaps between the roof and sides of the box, or drill ¼ inch holes just below the roof.

_Drainage_

Water becomes a problem when it sits in the bottom of a bird house. A roof with sufficient slope and overhang offers some protection. Drilling the entrance hole on an upward slant may also help keep the water out. Regardless of design, driving rain will get in through the entrance hole. You can assure proper drainage by cutting away the corners of the box floor and drilling ¼-inch holes. Nest boxes will last longer if the floors are recessed about ¼ inch.

_Entrance Hole_

Look for the entrance hole on the front panel near the top. A rough surface both inside and out makes it easier for the adults to get into the box and, when it’s time, for the nestlings to climb out.

If your box is made of finished wood, add a couple of grooves outside below the hole. Open the front panel and add grooves, cleats or wire mesh to the inside. Never put up a bird house with a perch below the entrance hole. Perches offer starlings, house sparrows and other predators a convenient place to wait for lunch. Don’t be tempted by duplexes or houses that have more than one entrance hole. Except for purple martins, cavity-nesting birds prefer not to share a house. While these condos look great in your yard, starlings and house sparrows are inclined to use them.

_Accessibility_

Bird houses should be easily accessible so you can see how your birds are doing and clean out the house. Monitor your bird houses every week and evict unwanted creatures such as house sparrows or starlings.

Be careful when you inspect your bird boxes—you may find something other than a bird inside. Don’t be surprised to see squirrels, mice, snakes or insects. Look for fleas, flies, mites, larvae and lice in the bottom of the box. If you find insects and parasites, your first reaction may be to grab the nearest can of insect spray. If you do, use only insecticides known to be safe around birds: 1 percent rotenone powder or pyrethrin spray. If wasps are a problem, coat the inside top of the box with bar soap.

Here’s how to check your nest boxes for unwanted visitors:

Watch the nest for 20-30 minutes. If you don’t see or hear any birds near the box, go over and tap on the box. If you hear bird sounds, open the top and take a quick peek inside. If everything is all right, close the box. If you see problems (parasites or predators), remove them and close the box.

A bird house with easy access makes the job simple. Most bird houses can be opened from the top, the side, the front or the bottom. Boxes that open from the top and the front provide the easiest access. Opening the box from the top is less likely to disturb nesting birds. It’s impossible to open a box from the bottom without the nest falling out. While side- and front-opening boxes are convenient for cleaning and monitoring, they have one drawback: the nestlings may jump out. If this happens, don’t panic. Pick them up and put them back in the nest. Don’t worry that the adults will reject the nestlings if you handle them. That’s a myth; most birds have a terrible sense of smell.

If you clean out your nest boxes after each brood has fledged, several pairs may use the nest throughout the summer. Some cavity-nesting birds will not nest again in a box full of old nesting material.

In the fall, after you’ve cleaned out your nest box for the last time, you can put it in storage or leave it out. Gourds and pottery last longer if you take them in for the winter. You can leave your purple martin houses up, but plug the entrance holes to discourage starlings and house sparrows.

Leaving your wood and concrete houses out provides shelter for birds, flying squirrels and other animals during winter. Each spring, thoroughly clean all houses left out for the winter.

_Limiting Predator Access_

Proper box depth, and roof and entrance hole design will help reduce access by predators, such as raccoons, cats, opossums, and squirrels. Sometimes all it takes is an angled roof with a three-inch overhang to discourage small mammals.

The entrance hole is the only thing between a predator and a bird house full of nestlings. By itself, the ¾-inch wall is not wide enough to keep out the arm of a raccoon or house cat. Add a predator guard (a ¾-inch thick rectangular wood block with an entrance hole cut in it) to thicken the wall and you’ll discourage sparrows, starlings, and cats.

Bird House Placement

Where you put your bird house is as important as its design and construction. Cavity-nesting birds are very particular about where they live. If you don’t have the right habitat, the birds are not likely to find the house. You can modify your land to attract the birds you want to see by putting out a bird bath, planting fruit-bearing shrubs, including more trees or installing a pond with a waterfall.

Once you’ve matched up the right bird house with the appropriate habitat, you have to know where to put the nest box. Should you hang it from a tree limb, nail it to a fence or mount it on a pole or a tree trunk?

Most species require a fairly narrow range of heights for nest boxes. After checking the table in this brochure, pick a height that’s convenient for you. After all, you will want to watch what goes on and keep the box clean. If you want to watch chickadees from your second floor window or deck, fifteen feet is reasonable but it’s a lot easier to clean out a box at eye level.

Here are some tips on where to put bird houses:

don’t put bird houses near bird feeders.

houses mounted on metal poles are less vulnerable to predators than houses nailed to tree trunks or hung from tree limbs.

use no more than four small nest boxes or one large box per acre for any one species.

put about 100 yards between bluebird boxes and 75 yards between swallow boxes. (If you have both species, pair the houses with one bluebird box 25 feet from a swallow box.)

don’t put more than one box in a tree unless the tree is extremely large or the boxes are for different species.

if you have very hot summers, face the entrance holes of your boxes north or east to avoid overheating the box.

Protection from Predators

_Cats_

Nesting birds are extremely vulnerable to cats, as are fledglings and birds roosting for the night. Bell collars on cats offer birds little protection. Nailing a sheet metal guard or cone to a tree trunk is unsightly, but may deter less agile felines. Houses mounted on metal poles are the most difficult for predators to reach, especially if you smear the poles with a petroleum jelly and hot pepper mixture. The best deterrent is for owners to keep their cats inside whenever possible.

_Dogs_

Pet dogs are a hazard to nestlings in the spring and summer. Don’t let your dog run loose during nesting time.

_Squirrels_

Red squirrels, and sometimes gray squirrels, can become a serious menace to bird houses and the birds themselves. If you find your nest hole enlarged, chances are a red squirrel is the culprit. Once inside the box, squirrels make a meal of the eggs and young. Adding a predator guard made of sheet metal to the entrance hole is usually enough to keep squirrels out.

_Raccoons and Opossums_

Raccoons and opossums will stick their arms inside nest boxes and try to pull out the adult, young, and eggs. Adding a ¾-inch thick predator guard to the bird house or an inverted cone to its pole support is a simple solution.

_Snakes_

Snakes play an important part in the balance of nature. If you find one in your bird house, don’t kill it. Snake-proof your house by putting it on a metal pole lathered with petroleum jelly or red cayenne pepper.

_House Sparrows and Starlings_

If you don’t discourage them, these two nuisance species introduced from Europe will harass or kill cavity-nesting birds. Since house sparrows and starlings are not protected by law, you may destroy their nests. But remember, other birds are protected by law.

_House Wrens_

House wrens sometimes interfere with the nesting success of other birds by puncturing their eggs. But, unlike the house sparrow and starling, these birds are native to North America and are protected by law. Don’t be tempted to intervene when wrens appear at your backyard birdhouse.

_Insects_

Many insects lay their eggs and pupate in bird houses. Inspect your bird houses for signs of gypsy moths, blow flies, wasps, ants, gnats and bees. Keep bees and wasps from attaching their nests by coating the inside of the roof with bar soap. In areas where gypsy moths abound, avoid placing boxes in oak trees, which the gypsy moths favor.

Pyrethrin and rotenone insecticides are recommended for killing fly larvae, bird lice and mites after birds have finished nesting for the season.

Attracting Birds

As people learn to enjoy the beauty of birds around their home, they may wish to improve the “habitat” in their yard so that more birds will visit their property. You can attract birds by placing bird feeders, nest boxes and bird baths in your yard, and by planting a variety of trees, shrubs, and flowers. These can provide good nesting sites, winter shelter, places to hide from predators and natural food supplies that are available year-round.

Landscaping for Birds

The most surefire way to attract birds to your backyard is to make certain the appropriate habitat is available to them. You may be lucky and already have a good supply of food, shelter, and water available for our feathered friends. In that case, you have to do little more than stand back and watch.

However, for most backyards, bird habitat must be created. It’s called “landscaping for birds” and it can be as simple or extravagant as you wish. Whatever the approach, anyone who has ever tried this type of landscaping comes away with a real love for it after their first sparkling hummingbirds hover at the coral bells, or the perky catbird comes down for a drink of water from the birdbath, or the sleek waxwings gather en masse to sample bittersweet berries.

Benefits of Landscaping for Birds

You can derive many benefits from landscaping to attract birds to your yard:

_Increased Wildlife Populations_

You can probably double the number of bird species using your property with a good landscaping plan.

_Energy Conservation_

By carefully arranging your conifer and hardwood trees, you can lower winter heating and summer cooling bills for your house.

_Soil Conservation_

Certain landscape plants can prevent soil erosion.

_Natural Beauty_

A good landscaping plan contributes to a beautiful, natural setting around your home that is pleasing to people as well as birds.

_Wildlife Photography_

Wildlife photography is a wonderful hobby for people of all ages.

_Birdwatching_

Try keeping a list of all the birds you see in your yard or from your yard. Some people have counted nearly 200 species of birds in their yard!

_Natural Insect Control_

Birds such as tree swallows, house wrens, brown thrashers and orioles eat a variety of insects.

_Food Production_

Some plants that attract wildlife are also appealing to humans. People and wildlife can share cherries, chokecherries, strawberries, and crabapples.

_Property Value_

A good landscaping plan can greatly increase the value of your property by adding natural beauty and an abundance of wildlife.

_Habitat for Kids_

Some of the best wildlife habitats are the best habitats for young people to discover the wonders of nature. A backyard bird habitat can stimulate young people to develop a lifelong interest in wildlife and conservation.

Basics of Landscaping for Birds

Landscaping for birds involves nine basic principles:

_Food_

Every bird species has its own unique food requirements that may change as the seasons change. Learn the food habits of the birds you wish to attract. Then plant the appropriate trees, shrubs, and flowers to provide the fruits, berries, seeds, acorns, nuts and nectar.

_Water_

You may be able to double the number of bird species in your yard by providing a source of water. A frog pond, water garden, or bird bath will get lots of bird use, especially if the water is dripping, splashing or moving.

_Shelter_

Birds need places where they can hide from predators and escape from severe weather. Trees (including dead ones), shrubs, tall grass and bird houses provide excellent shelter.

_Diversity_

The best landscaping plan is one that includes a variety of native plants. This helps attract the most bird species.

_Four Seasons_

Give birds food and shelter throughout the year by planting a variety of trees, shrubs and flowers that provide year-round benefits.

_Arrangement_

Properly arrange the different habitat components in your yard. Consider the effects of prevailing winds (and snow drifting) so your yard will be protected from harsh winter weather.

_Protection_