That Bird Blog – Bird Care and History for Pet Birds

Those Observant Parrots
Parrot keepers are well aware that individual birds often “take to” one person or to people of one sex only, and respond with aggression or fear to others.  Long –term pet parrots most definitely react differently to the various people living in the household – seeming to know what they can “get away with” with one person,  when to expect a scratch on the head from another, and so on.

The Brightest Birds
Wildlife biologists at the University of Washington have recently (August, 2008) confirmed that crows do indeed recognize and remember the faces of individual people.  Crows and their relatives – jays, ravens and magpies – are among the most intelligent of birds, and are often compared to parrots in this regard.  I’m quite sure that the results of this research would be duplicated if conducted on parrots.

The Experiment
Researchers wearing masks designated as “dangerous” trapped, banded and released crows on the university’s grounds.  While subsequently walking about the campus wearing the “dangerous” masks, the researchers were consistently scolded and mobbed (harassed) by crows….when unmasked or wearing “neutral” masks, the researchers went unnoticed.  When paired with “neutral” mask wearers on walks, only the “dangerous” researchers drew the crows’ wrath.

Birds Teaching Birds
What’s more, although only 7 crows were trapped (the experiment was later repeated with a larger sample), 47 individual crows scolded the researchers.  Although crows will respond to the alarm calls of others, in some instances the originally trapped crows were not present when others sent up the alarm – obviously the trapped crows had somehow passed along their new-found knowledge to their neighbors!

Implication for Conservation
We’ve long known that fledgling birds will imprint (bond with, to the exclusion of their own species) upon general human characteristics…while hand-rearing barn owls and other species destined for release, I always work from behind a curtain, and such is standard protocol at most zoos.  This study, however, offers the first concrete evidence of individual face recognition.

I’m sure you parrot owners have many stories of your pets’ own remarkable abilities.

An interesting article providing further evidence of the keen environmental and people-oriented awareness possessed by parrots is posted at:
http://www.nipsparrot.org/Educational%2520Articles_files/Phobic%20Parrots-Wilson-Edited_files/Phobic%20Parrots-Wilson-Edited.htm

Ants and other insects, interesting as they may be in their own right, are the bane of pet and zoo keepers alike.  Eliminating them around pets is especially difficult as commercial sprays are harmful to a wide variety of creatures (ourselves included, no doubt!), with birds being particularly sensitive (please see my article “Protecting Birds from Hazardous Fumes” for further information).

Ants are extremely resourceful creatures.  When working with leaf cutter ants (Atta cephalotes) at the Bronx Zoo, I observed a dramatic increase in the queen’s egg production shortly after empty nesting chambers were added to the colony’s enclosure – the workers somehow communicated to her the fact that more space was available.  So merely poisoning a few workers will not reduce ant numbers at all – in fact, it may set up a call for more eggs!

What is needed is a toxin that will be taken by the worker ants to the nest, and shared with the queen and larvae.  A number of commercial ant baits promise just this, but usually deliver mixed results.  The most effective and relatively benign poison I’ve run across consists of a mixture of 2 tablespoons of Boric Acid to 6 tablespoons of sugar, dissolved in a quart of water.

To apply the bait, soak cotton wads or household sponges in the solution and place them into small plastic containers (i.e. take out food containers).  Cut small access holes along the bottom and keep the containers tightly covered to retard evaporation.  Re-dip the sponges when they begin to dry.  Use latex gloves when handling the mixture.  A wide variety of ant species accept this bait, and it usually eliminates the colony in short order.  It is tasty and toxic to roaches as well, but I have another trick up my sleeve for them…please stay tuned.

Overview
Today I’d like to cover a bird that, while generally illegal to keep in the USA, is one of the largest and most impressive species that might reasonably be encountered anywhere within the USA, and beyond – the Great Horned Owl.

Their occasional propensity for living near people (until recently, a pair nested in Battery Park, Manhattan) results in a number being injured each year.  I have cared for several such birds, and suggest that anyone interested in doing likewise apply for the necessary state permits and seek training as a Wildlife Rehabilitator.  Hand-raised Great Horned Owls are gaining popularity with European aviculturists, and a few are even used, falconry style, to hunt game.

Physical Description
One of the largest of the world’s 135 owl species, in the Western Hemisphere the Great Horned is exceeded in size only by the Great Gray Owl (which it outweighs) and the Snowy Owl.  It reaches 25 inches in length, and the wings may span 5 feet (sizes vary greatly among various populations).

The eyes are bright yellow, the throat white and the head is topped with prominent ear tufts.  The color ranges from white in the Arctic to near black along the Pacific coast, but most individuals are varying shades of mottled tan, brown or dark gray.  Females may be up to 20% larger than males.
Range
The vast range encompasses nearly all of North and South America.  At least 13 subspecies are found from northern Alaska and Labrador through the southern 2/3 of Canada, in all 48 lower states and Mexico and south to the extreme southern tip of South America.  Only the Barn Owl, which lives on all continents except Antarctica, is more widespread.

Habitat
Extremely varied, including tundra, deserts, swamps, grasslands, agricultural areas, city parks, mixed and coniferous forest, salt marsh, rainforest edges and mountain slopes.

Densities can be quite high in prime habitat.  Suburban areas, with their mix of towns, fields, forests and parks, prove quite inviting to Great Horned Owls.  Wildlife rehabilitators on Long Island, NY rarely release birds there as nearly every suitable area has been claimed by a nesting pair.

I have found Great Horned Owls nesting in California desert caves and abandoned buildings in NYC, along a salt water bay in a NYC suburb, at a rainforest edge in Costa Rica and on farms in the Venezuelan llanos.

Diet
This is our most powerful owl, and one of the world’s most formidable avian predators.  Over 260 prey species have been recorded, including raccoons, opossums, muskrats, flying squirrels and other rodents, smaller owls and birds to the size of red-tailed hawks and great blue herons,  small alligators, snakes, turtles and frogs, large insects, fish (will wade in shallow water) and road-killed animals.

It is one of the few predators that regularly takes striped skunks and porcupines.  It will, in most “un owl-like” fashion, do battle on the ground – I still recall a striking series of photos from the 1960’s Time-Life Nature Library Series depicting a Great Horned Owl “wrestling” with (and nearly losing its life to) a large bullsnake.

Owls living near farms take ducks, turkeys, geese and other fowl, and have been observed walking into coops to snatch chickens.  In NYC and other urban areas, Great Horned Owls feed largely upon rats and roosting pigeons, but have been known to take domestic cats.

Reproduction
In the northeastern USA, mating occurs in January, and females are incubating eggs by February, when snows are still likely.  The owls often appropriate the nests of red-tailed hawks and other large birds – sometimes driving off or even killing the owners.  Depending upon the habitat, rock ledges, tree cavities, abandoned buildings, barns, large cactus plants or even the ground may serve as a nest site.

The female lays 1-5 eggs and incubates the clutch for 35-40 days (males in some populations may incubate as well).  The young are fed by both parents and fledge in 8-10 weeks.

Both parents are extremely aggressive in defending the nest, and quite literally will not cease their attacks until the intruder, human or otherwise, has been driven off.  A coworker of mine at the Bronx Zoo once entered a pair’s exhibit without a hard hat and landed in the hospital with severe scalp lacerations as a result.

Great Horned Owl pairs defend specific home territories for many years, but forage singly outside of the breeding season.

Miscellaneous
Owls are often referred to as “Birds of Prey”, along with hawks, falcons, eagles and vultures.  They are not, however, related to any of these birds.

Great Horned Owls are classified within the owl family Bubonidae (the Eagle Owls) and are the only representative of the group to dwell in the Americas.  Eleven other eagle owl species, all large, formidable predators (the massive European eagle owl occasionally takes deer fawns), are found in Europe, Africa and Asia.  In terms of their role in the environment, eagle owls are considered to be the nocturnal equivalent of the diurnal eagles and larger hawks.

Next time I’ll discuss Great Horned Owls in captivity, and relay a few personal experiences.

Further information on the Great Horned Owl, including photos and voice recordings, is posted at:
http://www.owling.com/Great_Horned.htm

Image originally posted by Billy Hunt and referenced from Wikipedia Commons.

Please see Part I of this article for an overview and a list of other toxic plant species. Many of the plants listed there and below are also toxic to mammals, and therefore should not be offered to hamsters, gerbils, mice, chipmunks or other pets. Insect-fanciers have an easier time – some of the most deadly plants are avidly consumed by stick insects, leaf insects and other herbivorous species.

You can read about the symptoms of plant poisoning in birds and other pets at:
http://davesgarden.com/guides/articles/view/395/

In years past, caged canaries were used to warn coal miners (by becoming lethargic and/or deceased) that oxygen levels were dropping or toxic fume levels were rising – so much so that the term Canary in the Coal Mine now enjoys popular usage is applied to many situations.  Canaries and other birds are extremely sensitive to airborne hazards – useful to miners but troubling to pet owners.

The most commonly encountered fumes likely to cause problems in the average household arise from the materials used to treat non-stick cookware  – Teflon and similar products applied to pans, toasters, irons and the like.  When over-heated, these coatings release gasses that, while seemingly harmless to humans and furry pets, can kill birds. 

Move your bird to a safe area when cooking or using an oven in self-cleaning mode, and try not to burn anything (good advice in general!).  Good ventilation is an important safety measure, but may not be enough in some situations.

Aerosol cookware coatings are also dangerous to birds if overheated.  Other products to avoid using around your feathered friends are air fresheners, general cleaning products, insecticides and cigarettes (most will be safe once dried and cleared from the air by time and ventilation).  A number of insecticides are marketed as “pet safe” – these are usually formulations of Precor, Pyrethrin or Fenoxycarb – but it is best to wait until they have dried before returning your pet to treated areas.

Additional information on airborne and other hazards pet birds may face is posted at:
http://www.bird-haven.org/toxicproducts.html