Storey's Guide to Raising Chickens (33 page)

For a sizable flock, especially pastured, a guardian animal such as a dog or burro makes a good investment. If you opt for a canine, be sure he’s reliable. A poultry breeder once remarked that her thriving repeat business was largely
due to dogs — not just neighborhood dogs and roaming packs that preyed on chickens, but also pets owned by the same people who kept her busy hatching chicks to replace all the chickens that were eaten.

If you have a problem with a predator that comes back repeatedly, you might call your local wildlife or animal control agency to see if they’ll send out a trapper. Another option is to set a trap yourself. If you use a live trap with the intent of releasing the predator in some far-off location, be aware that many animals are territorial and eventually find their way back home. Others come in families, so catching one won’t necessarily solve your problem. And if your marauders are a family of ’possums, think twice about eliminating them — you may end up with a rat problem instead.

A predator-control option favored by many rural folks is to stand guard and shoot. If the marauder is your neighbor’s dog, be sure to check local laws regarding
your obligation to notify the neighbor about your intentions. And if you’re dealing with a wild animal that’s protected by law, your best option is to eliminate the point of entry.

One perfectly legal method that works on every predator prowling between dusk and full daylight is a solar-powered blinking red light called Nite Guard. The pulse of light it emits once every second between dusk and daylight gives a wary predator the impression another animal is watching, causing the prowler to skulk away. It even works on two-legged thieves, who believe it’s a security system. We mounted one next to the chicken-size door of our henhouse and have had no more problems with early-morning pilfering of feed, eggs, or chickens.

My first flock of chickens came with a 1-acre (0.4 ha) ranchette in a rapidly suburbanizing area, where the chief threats were dogs, rats, and ever-tightening zoning regulations. Because of the latter, we now raise chickens on a rural farm at the end of a dirt road, where a steady and varied parade of industrious wildlife attempts to share our birds. Because the wild animals delight us as much as they attempt to frustrate our poultry-keeping efforts, and because we are encroaching on their territory, we do our best to identify the source of any predation and take appropriate defensive measures to protect our flocks while letting the wildlife be.

Under temperate conditions a chicken doesn’t need central heat and air to remain comfortable year-round. In cold weather, a chicken’s body warms itself by producing approximately 35 BTUs per hour through physical activity and metabolic processes sustained by feed. In moderately warm weather a chicken’s body cools itself by transporting internal heat to the external environment with the aid of its circulatory, respiratory, and excretory systems. In extremely hot or cold conditions, however, your chickens’ temperature-regulating systems may need a little help.

During long periods of extreme cold or heat, laying hens stop production and all chickens suffer stress. Chickens generally suffer less in cold weather than in hot weather, as long as their drinking water doesn’t freeze and their housing is neither damp nor drafty. When temperatures reach 104°F (40°C) or above, chickens can’t lose excess heat fast enough to maintain the proper body temperature and may die. A chicken’s body controls temperature by transferring heat between itself and its environment in the four ways described on the next page.

Radiation
involves heat transfer between a chicken and nearby objects. If the environment is warmer than the bird’s body, nearby objects warm the bird; if the environment is cooler, heat radiates from the bird to the environment. Examples of radiation control include putting a reflective roof on the coop to prevent radiant heat gain from the sun in summer and insulating the roof to prevent radiant heat loss from birds in winter. At low temperatures most of the heat a bird’s body loses is through radiation and convection.

Convection
is the transfer of heat between a bird and the surrounding air. Drafts and breezes cause warm air close to a bird’s body to be replaced by cooler air. In winter convection causes a bird to chill. At low temperatures you can reduce convection by eliminating drafts that carry away warm air trapped in a bird’s ruffled feathers.

In summer convection cools a bird but only as long as the surrounding air is cooler than the bird’s body temperature of 103°F (39.5°C). At air temperatures above 70°F (21°C), improve convection by opening doors and windows and, if necessary, by installing a fan. At 85 to 90°F (29 to 32°C), a chicken exposes more of its body to moving air by holding out its wings.

Conduction
is heat transfer between a chicken and objects its body contacts — floors, litter, nests, and so forth. As you might expect, warm objects warm the bird, cool objects cool it. The parts of a bird’s body having the most contact with external objects are its feet, but since the feet are quite small, their conductive influence is minimal. Holes for dust baths are also sources of conduction: cool soil or fresh litter can be a significant factor in keeping a bird cool in summer; warm, composting litter provides warmth in winter.

Excretory heat transfer is a type of conduction that occurs when a bird drinks cool water, warms the water within its body, and eliminates the warm water in its droppings. At high temperatures chickens increase the rate of heat loss by drinking more than usual, which causes their droppings to become loose and watery. Off-color droppings during the heat of summer may be a sign the birds aren’t getting enough to drink. At high temperatures, excretion and evaporation account for most of a chicken’s body-heat loss.

Evaporation
is the loss of latent body heat that occurs when the environmental temperature approaches a chicken’s body temperature, and its body heat vaporizes liquid on the body’s surface. Evaporation is an effective cooling method only when the relative humidity is low. Each 17°F (9.5°C) increase in air temperature doubles the air’s capacity to carry moisture, up to a point — air at any temperature can accept only so much moisture, and if the air is already saturated, it can’t hold any more.

Respiratory heat transfer is a type of evaporation occurring when a bird inhales air that’s cooler than the bird’s body, and exhales moisture-laden warm air. The moist-air passages in the bird’s extensive respiratory system — which include not only lungs but also air sacs among its organs, and air spaces in some of its bones — help a bird lose internal body heat. In warm weather a bird increases the rate of heat loss by panting. Since coops tend to be high in humidity due to moisture produced by respiration and excretion, good ventilation and proper litter management are important temperature-controlling measures.

Low humidity on summer days lets you take advantage of evaporation to cool birds by frequently hosing down the coop’s outside walls and roof, and occasionally misting adult chickens, when the following conditions prevail:

Air temperature is above 95°F (35°C).

Air humidity is below 75 percent.

Air circulation (convection) is good.