Birds hitting windows

Birds hitting windows is a common problem. Depending on the lighting, a window – even a relatively small one – can behave like a mirror. A bird in a hurry, such as one threatened, can mistake the window for open spaces.

With most household windows and doors, a crash happens only rarely, if ever. However, if you have windows – particularly picture windows – that birds regularly collide with, consider a product like Window Alert. These are plastic decals that are virtually invisible to humans on the inside of the house, but are very visible to birds on the outside.

According to the manufacturer, “The decal contains a component which brilliantly reflects ultraviolet sunlight. This ultraviolet light is invisible to humans, but glows like a stoplight for birds.”

The product functions sort of like those advertising coatings that you see on commercial vans and city buses that cover not only the metal surfaces of the vehicle but also the windows. People inside can see out perfectly well, though from the outside the window looks like part of a sign.

The decals, which come in various shapes including leaves and snowflakes, are sold in many stores that serve bird watchers and feeders. For more information, see windowalert.com.

The hungry hawks

The striking Rich Josephs photograph of this of a Red-tailed Hawk consuming a crow is a dramatic example of why hawks and other raptors were once hated and hunted. Hawks, owls and eagles feed on a variety of birds and smaller mammals. For hawks and owls, at least, mammals and birds are their primary source of food.

Catching squirrels, rabbits, mice, and birds in the wild is often not easy, and requires skill, stealth and timing. More often than not, the raptor is unsuccessful and the prey escapes.

When farmers took over much of the landscape in the 18^th and 19^th Centuries, they eliminated some raptor prey, but also introduced others. What’s more, some of the new fare were easy pickings.

Chickens were so popular with some hawk species that any hawk that attacked domesticated fowl was called a “chicken hawk.” However, the Red-tailed Hawk was probably what farmers saw most, and was the most feared “chicken hawk.”

In a way, this is unusual. Red-tails are not true “bird hawks.” Many Accipiters like the Sharp-shinned and Cooper’s Hawks feed primarily on birds and are designed to catch them on the wing – they are smaller, sleeker and have long tails that allow them to maneuver quickly. By comparison, the bigger Red-tailed Hawk is not as agile. It can catch an occasional crow or waterfowl, but it’s unlikely a Red-tail could nail the chickadee or titmouse that a Sharpie can catch.
When the European farmers arrived, they provided virtually flightless fowl to the native raptors. Domesticated chickens were slow, fat and tasty. It was Red-tail heaven – until the farmers got good guns. Hawks were treated as vermin, bounties were paid for their bodies, and countless numbers of them were killed.

Even in modern-day Ridgefield, “chicken hawks” are at work. Last fall, we got a call from Wendy Llewellyn who had recently returned to maintaining full-sized, egg-laying chickens at her home. One day, “they were making strange noises,” she said. She looked outside and “there was what I assume was a hawk, trying to take off with one of them,” Wendy said. “I ran out and the hawk dropped the chicken.”

A week earlier, her cat had been limping. “When I brought her to the vet, he said she looked like she had been in a fight and was covered with lacerations,” Wendy said, wondering whether it was a tom cat – or the hungry hawk.

Small mammals are the main fare of the Red-tail, our most common hawk, and if the opportunity arises, the Red-tail may attack small dogs and cats.

“Large raptors, such as Red-tailed Hawks and Great Horned Owls, can indeed kill a small pet,” says Hawks Aloft, a raptor conservation organization. “We have received dozens of inquiries about six-pound dogs, ten-pound dogs, etc., all the way up to a 60-pound dog. There is no specific cut-off weight at which your pet’s safety is guaranteed. If the size of your dog or cat is similar to or not much larger than naturally occurring raptor prey, there is a risk.”

Early one morning a couple years ago, I was walking our nine-pound Chihuahua, Charley, down the road when suddenly I saw a Red-tail flying straight at us, only about eight feet off the ground. I am sure he was eying Charley, who was about 10 feet ahead of me on a leash. However, as soon as the hawk noticed me, he veered upward and headed off into the woods.

We never leave Charley alone in the yard. He and any other small dog or cat could be lunch for not only large raptors, but coyotes, the recently reintroduced Fishers (large, mammal-eating weasels), perhaps foxes, and maybe even cougars (reliably sighted in Ridgefield last year).

So keep Fido and Kitty indoors or under surveillance.

Saving money on feeding birds

With everyone economizing in these tight times, feeding the birds may seem a luxury that should be shelved until “prosperity” returns.

Certainly, the birds don’t need our food to survive winter, except perhaps in unusually severe conditions. Most of their food is obtained from the wild, not feeders.

Nonetheless, bird feeding is one of North America’s most popular pastimes, with an estimated 55 million people owning feeders. The reason most people feed the birds is the close-up connection with nature that it offers. Feeding birds are simply fun to watch. And in these times, we could use some fun!

So let’s feed with efficiency as well as economy. With that in mind, here are some suggestions.

• Perhaps the most important consideration in having an efficient feeding station is squirrels. These wily rodents can quickly consume large amounts of expensive seed. Make sure your feeder is absolutely squirrel proof — which is not impossible. The best setup I’ve found is mounting on a six-foot pole, away from nearby trees (from which the squirrels can leap), and using a cone to prevent their climbing up the pole (see photo). There hasn’t been a squirrel on our feeder in years.
  

• Use a feeder that distributes the seeds efficiently and does not allow them to spill onto the ground. Some tube feeders tend to be wasteful. I like a feeder that provides a platform for the birds to land on and carefully pick a seed, without spilling or tossing others on the ground.
  

• Some people don’t like large birds like Mourning Doves or Blue Jays hogging the food. You can buy feeders aimed at only small birds. This will, of course, reduce overall seed consumption, but also reduces the variety of birds you’ll see.
  

• To minimize waste, buy seeds that your birds like. The best all-around food is hulled (shelled) sunflower seeds, but these may be beyond your budget. Whole black oil sunflower seeds are cheaper than hulled, but more expensive than mixes. However, cheap mixes may contain many “filler” seeds that are thrown away by popular feeder birds. They wind up as food for squirrels, chipmunks and maybe even mice on the ground.

• Shop around, of course. I can’t recommend a best source, but I always buy locally instead of on the Internet (who wants to pay shipping on 50 pounds of seed?). Look for fall sales at feed and hardware stores (though bargains are becoming less common as prices rise).
  

• You get the best prices buying in quantity, but make sure you have a cool, dry place in which to store the seeds; otherwise, the seeds can mildew or go rancid, and you wind up wasting money on spoiled seeds that birds won’t eat or, worse, may get sick eating. Put the seeds in a strong sealed container like a big garbage can, so that they won’t attract mice or squirrels (even in your cellar or garage).
  

• Many birds love suet. I’ve found that the “suet cakes” sold commercially do not last long — often, they have crumbled within a few days under hard whacks of visiting woodpeckers. I use real suet, the stuff butchers cut off beef. It lasts much longer and is enjoyed by a half dozen varieties of birds. Not many years ago, suet was something that butchers mostly considered waste. Some was packaged at 10 or 25 cents a pound and sold to savvy bird feeding customers. Today, meat arrives at most markets already “de-fatted,” and the butchers actually have to buy the suet from wholesalers! Thus, you will see suet prices that would have amazed an old-time butcher — a couple of dollars a pound for something they used to throw away or send to rendering plants. Nonetheless, in the long run, real suet may still be less expensive and more efficient than cake suet.
  

• Don’t waste money on a suet feeder. Use a mesh bag that produce, such as onions, garlic and avocados, is packaged in. Dispose of it after it’s been used for a while. When you buy suet, get the butcher to cut up the chunks into one-inch cubes, which are easier to fit into small mesh bags.

The wise and wary corvids

Many people have remarked on the story that appeared in a recent issue of The New York Times about a scientist’s discovering that crows can recognize individual human faces, but a perhaps more remarkable account of crow intelligence appears in the current issue of Bird Watcher’s Digest

It’s long been known that the corvids – crows, ravens, magpies, and jays – are quite smart, doing things like using tools and employing automobile traffic to break open nuts.

The Times story told of a wildlife biologist at the University of Washington who did an experiment in which crows on campus were trapped and banded by students wearing a “caveman” rubber mask. A Dick Cheney mask was used as a “neutral” mask by students not involved in the trapping.

In the weeks and months that followed, student volunteers who walked around campus with caveman masks were yelled at by the crows, which ignored the Cheney-masked students. Two years later, the number of crows recognizing the caveman mask as dangerous had spread to many birds that had never been trapped, indicating that parents and others in the community had taught offspring that this was a dangerous face.

In the current Bird Watcher’s Digest, columnist David Bird (yes, his real name – he’s a professor of wildlife biology at McGill University in Toronto) recounts an experience witnessed by ornithologist Russ Balda, which appeared recently in The Wilson Journal of Ornithology.

Mr. Balda was watching a crow eating seeds on a large platform feeder in Flagstaff, Ariz. Unlike other birds that came and went, the crow just stood there, hogging the feeder.

A Steller’s Jay landed on the edge of the platform and started scolding the crow for about 10 seconds. The crow ignored the pest, so the jay got closer and started making feinting movements at the crow. The crow then turned and faced the jay, which backed off.

The crow resumed eating, but the jay kept returning and repeating its harassment performance. Then the jay tried aerial techniques, swooping down on the crow a couple of times, without actual body contact.

After that didn’t work, the jay did something that astounded Mr. Balda. It flew to a mahogany tree and broke off a twig about four inches long. With the twig in its mouth and the narrow end pointed outward, the jay landed on the platform and lunged at the crow, narrowly missing it with the stick.

The crow jumped toward the jay, which dropped the twig and moved backward. The crow then picked up the twig and lunged at the jay!

The jay then took off, followed by the twig-wielding crow in hot pursuit.

In effect, and perhaps in fact, both the jay and the crow were employing a weapon – perhaps the first time this kind of “combat” has ever been observed, at least, by a scientist.

Weapon use of a different sort – bombing – has been observed in a couple of species. Professor Bird points out that Black Eagles have been recorded dropping sticks on the heads of intruders to their nests. “A female American Crow was observed dropping pine cones, not once but three times, onto the head of a human climber ascending to its nest,” he said.

Corvids’ using tools has been widely reported, and of course, a weapon can be considered a form of tool, but the Flagstaff indicate was different.

“Balda's observation may indeed be the first incident of a bird holding an object in a weapon-like fashion to undertake an aggressive action against another bird,” Professor Bird said.

He adds, “It was a pity that the crow did not have its own stick to duel with the jay.”

Two-ton snakes

What is it about snakes?

Is it that they are legless and armless, so much different from our well-appendaged selves? Is it because they slither so low and we walk so tall?

Or is it just that we fear some rattler or copperhead will sink its fangs into a leg and send us to the Great Beyond?

Prejudice, pure and simple. The snake is a wonderful creature that spends its days making our lives better by gobbling up rats, mice, shrews, voles, and other vermin.

Fear not our snakes. Fear, instead, a real killer: the shiny, glittering, ordinary, everyday automobile.

Over the past century, cars have killed scores of people in my own little town. Not one person has died of snakebite – or even snake-fright.

Mousetrap in a tree

If you were to go walking in the woods on a moonlit night, a dog in a tree might watch you.

More likely, though, the gray fox would have slipped far away before you were anywhere near being seen by him. He would not have been pressed to run up a tree – a feat he can easily accomplish, unique among North American canines.

No, the fox would have heard you coming from a long distance off. Sensitive ears, able to detect a mouse squeak at 300 feet, help make him a valuable pest-control device. Vermin like rats and mice are among its favorite foods and, as disease and tick carriers, one of our least favorite visitors.

Early in the morning, in the pre-dawn light, you may spot the long, low form of a gray fox winding around your lawn, ears up, nose down, a four-footed mousetrap.

Mating matters

The season of nesting is a good time to take a look at the kinds of male-female relationships that exist in the bird world. Many birds form lifetime partnerships – though they may have quick “flings” on the side – while others mate for only short periods or have multiple mates.

Ornithologists describe three kinds of mating arrangements: monogamous, polygamous and promiscuous. In monogamous pair bonds, the birds mate for at least the breeding season, raising their young together. Ornithologist David Lack estimated that at least 90% of nest-raised birds come from monogamous pairs. So do 80% of precocial birds – those able to walk about and feed themselves shortly after birth.

In many, perhaps most cases, monogamous pairs remain mated until one of them dies. Canada Geese are among the most faithful birds, mating for as long as 20 years. Most gulls also pair for life. The Rose-breasted Grosbeaks at the left are monogamous. This system is the most efficient and effective, providing the best protection and service for the brood of nestlings.

Some birds, such as House Wrens, generally stay with one mate for only one brood. In fact, while the male is raising the first brood, the female may take off, find a new mate, and begin a second nest. Talk about energy!

In the case of polygamous pair bonds, one male or one female may have several mates. In the more common arrangement, like the harems of lore, one male has several females. This is called polygyny. Wild Turkeys, Ring-necked pheasants, grouse, Bobolinks, and Red-winged Blackbirds are polygynous. The male generally sticks with and protects his several wives and their offspring while each female takes care of raising the children. This system is more selective than one-on-one mating; The one male that is able to build a harem of several females will be stronger and perhaps healthier than the average male and will likely pass on these traits to offspring.

In a few species, the female makes use of several mates. The Spotted Sandpiper lays eggs in several nests and the males incubate them. This system, called polyandry, allows one female to produce many eggs and is useful in situations where the breeding season is short, such as in the Arctic.

Promiscuous mating occurs when two birds have sexual relations and part company. Typically, and perhaps not surprisingly, the male takes off, leaving it up to the female to raise the resulting family. The most famous practitioners of promiscuous mating are the hummingbirds and woodcocks. Dr. Steve Kress, a noted ornithologist with National Audubon, says that typically, either the brood is small, such as in hummingbirds, allowing the female to raise the chicks alone, or the offspring are precocial, as in woodcocks, able to walk and feed themselves soon after birth.

For a long time ornithologists thought that monogamous birds were totally faithful to one another. However, DNA testing and close observation have revealed that monogamous birds may have fleeting “affairs” with other partners.

Zoologist David Barash and Judith Eve Lipton reported in The Myth of Monogamy in 2001: “When it comes to actual reproduction, even bird species long considered the epitome of social monogamy, and thus previously known for their fidelity, are now being revealed as sexual adventurers. Or at least as sexually non-monogamous.” These include eagles and geese, long thought to be strictly monogamous.

Swans, doves, finches, hawks, wrens, flycatchers, thrushes, and warblers occasionally switch from monogamous to polygamous pair bonds.

What happens when a mate dies during the nesting season?

Birds that form monogamous pairs do so largely to share in the job of raising young. Nesting season is a dangerous time, full of threats to the parents as well as the eggs and nestlings. Predators, as well as disease and accidents, may kill birds, leaving a widow or widower to care for the nest. Among monogamous pairs, it’s difficult or impossible for one bird to find food and protect the nest.

Fortunately, there are what ornithologists Allan and Helen Cruickshank call “a floating population” of unmated birds that are available – even anxious – to jump in and replace missing mates.