Forest Fires - An Overview

How Forest Fires Start

Forest fires always start by one of two ways - naturally caused or human caused. Natural fires are generally started by lightning, with a very small percentage started by spontaneous combustion of dry fuel such as sawdust and leaves. On the other hand, human-caused fires can be due to any number of reasons. Some classifications include smoking, recreation, equipment, and miscellaneous. Human-caused fires constitute the greater percentage of forest fires in our forests, but natural fires constitute the great majority of the total area burned. This is because human-caused fires are usually detected early in their duration, and therefore they are usually contained easily. Natural fires, on the other hand, can burn for hours before being detected by firefighting authorities.

How Forest Fires Burn

There are three elements that are required for a forest fire to burn: Heat, Oxygen, and Fuel. This is the so-called "fire triangle". Without all three of these elements, the fire will go out. Furthermore, the fire will spread in the direction of the most abundant supply of the three elements, while its rate of combustion is usually limited by one of the three elements. Once the fire enters the combustion stage, there are three main types of classifications for the fire. A smoldering fire is one that emits smoke but no flame and is rarely self-sustained. A fire is classified as flaming combustion when flames are present. Charcoal can be formed in the absence of oxygen with this type of fire. Glowing combustion is a later stage of the fire and is characterized by a slower rate of combustion and blue flame. Forest fires can also be classified by what part of the forest they burn in:

* Ground fires occur on the ground, often below the leaves.

* Surface fires occur on the surface of the forest up to 1.3 meters high.

* Crown fires are the most dangerous fires and can spread the fastest. They occur in the tops of the trees. They can be: (a) dependent upon surface fires to burn the crowns, (b) active in which they occur at the same rate as surface fires, or (c) the most destructive, independent, where fire can "jump" from crown to crown.

It is not uncommon for two or three types of fires to occur simultaneously.

Fighting Forest Fires

Perhaps the most overlooked aspect of fighting forest fires is communication. It is vital that the proper authorities be notified as soon as possible when a fire occurs. Obviously, a fire, that is detected in its early stages will be much easier to extinguish than a fire that has been burning for some time but has only just been discovered because of lack of communication. Once a fire has been detected, the fire fighters must be transported to the fire and then apply suppression methods.

Transport and Suppression

One difficulty in fighting forest fires is transporting the firefighters to the fire. Obviously, wildland fires often occur in rather rugged terrain, so fire fighters often have to be transported in by air and then walk with their equipment overland. Once crews are to the fire, the suppression method they use depends on the type of fire.

* Ground fires are often best controlled by digging trenches in the soil layer.

* Portable water backpacks and firebreaks are often the most effective methods at controlling surface fires.

* Lastly, if a fire escalates to a crown fire, aerial support is used to suppress the fire with fire retardant chemicals and/or water. However, these fires are often very dangerous and human life always comes first in fire fighting; sometimes these fires are just allowed to burn until they run out of dry fuel.

Forest Fire Prevention

Grass fires are a major concern for firelighters in early spring; they get quickly out of control and can cause serious damage in agricultural and forested lands. Forest fire officials encourage people not to light grass fires or burn debris. Burning dry grass in fields or yard debris can spread to nearby forests.

Consider no-burn options. Many landfills offer designated days when yard debris can be disposed of at little or no cost. Many "how to" publications and advice are available about composting. On-site chipping may be feasible. Limbs and other debris may be piled for wildlife habitat if located where it does not pose a wildfire hazard.

Carelessly lit and tended campfires and smoking are another major concern throughout the burning season.

Every year, countless acres of forests are burned because of human carelessness. To help prevent fires in or near forest land during the forest fire season, the following steps should be followed:

1. Check local regulations regarding permit requirements and "burn ban" restrictions. These are available from your municipality, fire department or department of natural resources. They may include:

a. Obtaining a burning permit for burning grass, brush, slash or other debris in or within a prescribed distance of forest land;

b. A campfire permit and the landowner's permission for an open campfire, cooking fire or bonfire in or near forest land;

c. A work permit for any work in forest land involving two or more people.

2. Bum only natural vegetation or untreated wood products.

3. Burn piles are at least 50 feet from structures and 500 feet from any forest slash.

4. Clear the area around the burn pile of any flammable debris.

5. Keep firefighting equipment handy - a connected water hose or at least five gallons of water and a shovel should be nearby.

6. Don't burn if it's too windy to burn - if trees are swaying, flags are extended, or waves appear on open water.

7. Be prepared to extinguish the fire if it becomes a nuisance.

8. Attend the fire until it is completely out.

9. Smoking should not be done while moving from one place to another in forest land. Make sure your butt is out - "dead out!"

10. Power saws must have a proper muffler and be accompanied by a round point shovel or fire extinguisher.

11. Cars, trucks and machinery must have proper exhaust systems when

operated in or near forest land. Exhaust spark arresters are a requirement on certain machines.

12. Know your local emergency telephone number if a fire becomes uncontrollable.

4. Переведите вопросы и ответьте на них:

1. How do forest fires start?

2. What is the cause of natural fires?

3. What can human – caused fires be due to?

4. Why are human – caused fires usually contained easily?

5. What are three elements required for a forest fire to burn?

6. What are tree main types of classifications for the fire?

7. How can a smoldering fire characterized?

8. What is ground /surface/ crown fire? Characterize them, please!

9. What are the difficulties in fighting forest fires?

5. Переведите на слух:

Dry fuel such as sawdust and leaves; выявлять на ранней стадии; the rate of combustion; стадия возгорания; to emit smoke but no flame; низовой пожар; to occur on the surface of the forest; верховой пожар; to spread the forests; тушение пожаров; to transport the firefighters to the fire; бригады пожарников; portable water backpacks; выходить из под контроля; forest fire officials; сжигать сухую траву; to consider no-burn options; представлять угрозу; careless lit and tended campfires; сухостой; flammable debris; тушить окурки; exhaust spark arresters.

6. Переведите устно (рекомендуется для зрительно-устного перевода «с листа» с подготовкой или без подготовки):

Wildfires are common in many places around the world, including much of the vegetated areas of Australia, ‘veld’ of South Africa, forest areas of the United States and Canada, where the climates are sufficiently moist to allow the growth of trees, but feature extended dry, hot periods when fallen branches, leaves, and other material can dry out and become highly flammable. Wildfires are also common in grasslands and scrublands. Wildfires tend to be most common and severe during years of drought and occur on days of strong winds. With extensive urbanization of wildlands, these fires often involve destruction of suburban homes located in the wildland urban interface, a zone of transition between developed areas and undeveloped wildland.

Today it is accepted that wildfires are a natural part of the ecosystem of wildlands, where, at the least, plants have evolved to survive fires by a variety of strategies (from possessing reserve shoots that sprout after a fire, to fire-resistant seeds), or even encourage fire (for example eucalypts contain flammable oils in the leaves) as a way to eliminate competition from less fire-tolerant species. In 2004, researchers discovered that exposure to smoke from burning plants actually promotes germination in other types of. Most native animals, too, are adept at surviving wildfires.

On occasions, wildfires have caused large-scale damage to private or public property, destroying many homes and causing deaths, particularly when they have reached urban-fringe communities.

The aftermath of a wildfire can be as disastrous if not more so than the fire. A particularly destructive fire burns away plants and trees that prevent erosion. If heavy rains occur after such a fire, landslides, ash flows, and flash floods can occur. This can result in property damage outside the immediate fire area, and can affect the water quality of streams, rivers and lakes.

Wildfires burned long before humans evolved. One main component of Carboniferous north hemisphere coal is charcoal left over by forest fires. The earliest known evidence of a wildfire dates back to Late Devonian period (about 365 million years ago).

When the water reserves in the soil are between 100 % and 30 %, the

evaporation of water in plants is balanced by water absorbed from the soil. Below this threshold, the plants dry out and under stress release the flammable gas ethane (ethylene). A consequence of a long hot and dry period is therefore that the air contains flammable essences and plants are drier and highly flammable.

The propagation of the fire has three mechanisms:

* "crawling" fire: the fire spreads via low level vegetation (e.g., bushes);

* "crown" fire: a fire that "crowns" (spreads to the top branches of trees) can spread at an incredible pace through the top of a forest. Crown fires can be extremely dangerous to all inhabitants underneath, as they may spread faster than they can be outrun, particularly on windy days;

* "jumping" or "spotting" fire: burning branches and leaves are carried by the wind and start distant fires; the fire can thus "jump" over a road, river, or even a firebreak.

The Nevada Bureau of Land Management identifies several different wildfire behaviors. For example, extreme fire behavior includes wide rates of spread, the presence of fire whirls, or a strong convection column. Extreme wildfires behave erratically and unpredictably.

In southern California, under the influence of Santa Ana winds, wildfires can move at tremendous speeds, up to 40 miles (60 km) in a single day, consuming up to 1,000 acres (4 km²) per hour. Dense clouds of burning embers push relentlessly ahead of the flames crossing firebreaks without pauses.

The powerful updraft caused by a large wildfire will draw in air from surrounding areas. These self-generated winds can lead to a phenomenon known as a firestorm.

French models of wildfires dictate that a fire's front line will take on the characteristic shape of a pear; the major axis being aligned with the wind. In the case of the fires in southeastern France, the speed of the fire is estimated to be 3% to 8% of the speed of the wind, depending on the conditions (density and type of vegetation, slope). Other models predict an elliptical shape when the ground is flat and the vegetation is homogeneous.

Another type of wildfire is the smouldering fire. It involves the slow combustion of surface fuels without generating flame, spreading slowly and steadily. It can linger for days or weeks after flaming has ceased, resulting in potential large quantities of fuel consumed and becoming a global source of emissions to the atmosphere. It heats the duff and mineral layers,affecting the roots, seeds and plant stems at the ground.

Fires play an important role in the natural changes that occur in Earth's ecosystems. The diversity of plant and animal life in the world's forests, prairies, and wetlands is (partly) dependent on the effects of fire; in fact, some plants cannot reproduce without fire. Fire initiates critical natural processes by breaking down organic matter into soil nutrients. Rain then moves these nutrients back into the soil providing a rejuvenated fertile seedbed for plants. With less competition and more sunlight, seedlings grow more quickly. Wild animals deal with fire remarkably well. Birds fly out of the fire area, large animals leave the danger zone by escaping to ponds and streams, while others return to their burrows. Usually few animals are killed by fire.

Prescribed fire is one of the most important tools used today to manage Earth's diverse ecosystems. A scientific prescription, prescribed fires help create a mosaic of diverse habitats for plants and animals. If all fire is suppressed, fuel (grasses, needles, leaves, brush, and fallen trees) can build up and allow larger, and sometimes uncontrollable, fires to occur. If enough fuel builds up, the fires could be so intense that they may destroy the seeds in the soil and hinder new tree and plant growth. By burning away accumulated fuels, planned fires make landscapes safer for future natural fires.

State of the science. By 1990, global tropical deforestation was occurring

at a rate of about 1.8 percent of the world's total forest lands per year. Approximately 142,000 square kilometers of rainforest are eliminated annually - an area slightly larger than the state of Arkansas. Using data from satellite sensors, aircraft, and ground-based initiatives, scientists are working to develop a new global fire monitoring program that will enable them to better understand the myriad implications of this growing problem. Specifically, efforts are underway to quantify the total area of forests and grass land burned each year and to more precisely estimate the amount of resulting emission products. These newer and better data will facilitate development of more robust computer models that will enhance scientists' abilities to predict how biomass burning will impact climate, the environment, and air quality.

Since the beginning of the industrial revolution, humans have transformed about 40 percent of Earth's land surface and have increased carbon dioxide levels by about 25 percent. Scientists estimate that from 1850 to 1980, between 90 and 120 billion metric tons (90-120 trillion kilograms) of carbon dioxide were released into the atmosphere from tropical forest fires. Comparatively, during that same time period, an estimated 165 billion metric tons of carbon dioxide were added to the atmosphere by industrial nations through the burning of coal, oil, and gas. Today, an estimated 5.6 gigatons of carbon are released into the atmosphere each year due to fossil fuel burning. Burning of tropical forests contributes another 2.4 gigatons of carbon per year; or, about 30 percent of the total. Over the last decade, it seems that the regional distribution of biomass burning has increased worldwide, as well as the length of burning time. The result is a continuing increase in the release of emission products, and an increase in the severity of their impact on climate and on the environment. Scientists estimate that in just a few months the burning that took place in 1997 in Indonesia released as many greenhouse gases as all the cars and power plants in Europe emit in an entire year. After carbon dioxide, the most significant greenhouse gas is methane, another emission product from biomass burning (about 10 percent globally). Although methane is about 200 times less abundant than carbon dioxide in the atmosphere, molecule for molecule methane is 20 times more effective at trapping heat. Since the beginning of the Industrial Revolution, methane has doubled in the troposphere.

Additionally, its concentration has been increasing about 1 percent per year, so scientists are concerned that its relative significance as a greenhouse gas may dramatically increase in the future, although there are indications that this increase may have slowed down in the last decade. Nitrous oxide (N₂O) concentrations have been increasing at about 0.3 percent per year for the last several decades. Yet, nitrous oxide has a lifetime of 150 years in the atmosphere, which contrasts sharply with the 10-year lifetime of methane. A single nitrous oxide molecule is the equivalent of 206 carbon dioxide molecules in terms of its greenhouse gas effect. Biomass burning accounts for about 2-3 percent of the total amount of tropospheric nitrous oxide. Emissions of nitrous oxides and methane are further associated with the production of tropospheric ozone. Unlike "good" ozone in the stratosphere (upper atmosphere) that acts as a shield to screen out the sun's harmful ultraviolet rays, ozone in the troposphere is a pollutant that, when breathed, damages lung tissue and is also harmful to plants.

Greenhouse gases - such as carbon dioxide, methane, and nitrous oxide - are mostly "transparent" to incoming solar radiation; that is, they rarely interact with sunlight. However, these gases are very efficient at trapping heat radiated from the Earth's surface by absorbing and re-emitting it. There is a wide margin of error in the estimates of biomass burning given above significantly more error than in our estimates of industrial emissions.

7. Переведите письменно текст, расположив абзацы в логической последовательности:

Russia had less forest fires due to natural causes,not bureaucratic efforts

1. "It seems that it was а long time ago since chief forest managers, seated

in Moscow, were in forest, otherwise they would not have been so optimistic, ­comments Vladimir Zakharov, ISEU forest Campaign coordinator. - The easiest way to learn about the real situation would be to ask directly those working on location".

2. Indirectly, Mr. Kasparov confirms these comments. He admits, that the worst fire situation was in Ural Federal region due to weather conditions - high temperature, no rain, and strong wind. This leads to conclusion that overall situation with forest fires in Russia is а matter of luck and weather.

3. Federal Forestry Agency of Russia draws the results of forest fire season 2004. Manipulation with numbers gives the ground for positive work assessment. "In year 2004 in the forests managed by Ministry of Nature Resources 21 980 fires occurred, which is 1,3 times less than in year 2003. This is due both to favorable weather conditions and introduction of targeted funding for forest fire prevention and extinguishing" - claims Albert Kasparov, head of Forest Protection Department of Federal Forestry Agency.

4. Aviation Service of Forest Protection (AviaLesookhrana) experts have their own opinion on the issue. Even is the number of forest fires is lower this year, this does not necessarily mean positive assessment of the work done. Absolute assessment, with favorable weather conditions impact taken in account, gives different understanding of the year results. With such favorable weather, number of fires might have been much less, forest fire experts say.

5. The high-position forestry bureaucrat follows with statement that necessary amount of fuel and food was supplied timely, as well as repair of equipment and fire prevention activities were done.

6. True situation with funding was not also as optimistic as painted by Mr. Kasparov. Forest firemen calculations show that money was enough for only а month of work. Only weather conditions allowed to "stretch" the funds until August. After that there was а silent order - to fly out to location that are closer to the airports. The situation was saved only due to the absence of the autumn peaks of the fires. All this helped to cover up lags in the funding policy.

8. Переведите текст устно и письменно (может быть использован для абзацно-фразового перевода):

Forest fire and biological diversity

R. Nasi, R. Deппis., Е. Meijaard, G. Appleate aпd Р. Мооrе

Fire serves an important junction in maintaining the health of certain ecosystems, but as a result of changes in climate and in human use (and misuse) of fire. Fires are now a threat to many forests and their biodiversity.

Fire is а vital and natural part of the functioning of numerous forest ecosystems. Humans have used fire for thousands of years as а land management tool. Fire is one of the natural forces that has influenced plant communities over time and as а natural process it serves an important function in maintaining the health of certain ecosystems. However, in the latter part of the twentieth century, changes in the human-fire dynamic and an increase in ЕI Nino frequency have led to а situation where fires are now а major threat to many forests and the biodiversity therein. Tropical rain forests and cloud forests, which typically do not burn on а large scale, were devastated by wildfires during the 1980s and 1990s (FAO, 2001).

Although the ecological impact of fires on forest ecosystems has been investigated across boreal, temperate and tropical biomes, comparatively little attention has been paid to the impact of fires on forest biodiversity, especially for the tropics. For example, of the 36 donor-assisted fire projects carried out or ongoing in Indonesia, а mega diversity country, between 1983 and 1998, only one specifically addressed the impact on biodiversity.

Ecosystem effects of fire

Forest fires have many implications for biological diversity. At the global scale, they are а significant source of emitted carbon, contributing to global warming which could lead to biodiversity changes. At the regional and local level, they lead to change in biomass stocks, alter the hydrological cycle with subsequent effects for marine systems such as coral reefs, and impact plant and animal species' functioning. Smoke from fires can significantly reduce photosynthetic activity (Davies and Unam, 1999) and can be detrimental to health of humans and animals.

One of the most important ecological effects of burning is the increased probability of further burning in subsequent years, as dead trees topple to the ground, opening up the forest to drying by sunlight, and building up the fuel load with an increase in fire-prone species, such as pyrophytic grasses. The consequence of repeated burns is detrimental because it is а key factor in the impoverishment of biodiversity in rain forest ecosystems. Fires can be followed be insect colonization and infestation which disturb the ecological balance.

The replacement of vast areas of forest with pyrophytic grasslands is one of the most negative ecological impacts of fires in tropical rain forests. These processes have already been observed in parts of Indonesia and Amazonia (Turvey, 1994; Cochrane et al., 1999; Nepstad, Moreira and Alencar, 1999). What was once а dense evergreen forest becomes an impoverished forest populated by а few fire-resistant tree species and а ground cover of weedy grasses (Cochrane et al., 1999). In North Queensland in Australia, it has been observed that where the aboriginal fire practices and fire regimes were controlled, rain forest vegetation started to replace the fire-prone tree-grass savannahs (Stocker, 1981).

Impacts of human-induced or severe natural wildfire

On plant diversity

Wildfire is unusual in most undisturbed, tall, closed-canopy, tropical rain forests because of the moist microclimate, moist fuels, low wind speeds and high rainfall. However, rain forests may become more susceptible to fire

during severe droughts, as experienced during ЕI Nino years.

In these forests which are not adapted to fire, fire can kill virtually all seedlings, sprouts, lianas and young trees because they are not protected by thick bark. Damage to the seed bank, seedlings and saplings hinders recovery of the original species (Woods, 1989). The degree of recovery and need for rehabilitation interventions depends on the intensity of burning (Schindele, Thoma and Panzer, 1989).

Tropical forests are also subject to fires started by humans for agricultural clearing. Deforestation fires, which are more common in disturbed forests, can vary in intensity and burn standing trees, at the worst completely burning the forest leaving nothing but bare soil.

There is some concern that salvage logging (removal of dead timber from severely burned logged-over forest or burned primary forest), used as а management and financing tool after fires in Indonesia in 1997-1998, may adversely affect the course of vegetation succession (van Nieuwstadt, Sheil and Kaгtawinata, 2001).Although fire is а frequent natural disturbance in boreal forests and they usually regenerate easily after fire, frequent high-intensity fires can offset this balance. As а result of extremely severe fires in the Russian Federation in 1998, more than 2 million hectares of forest have lost most of their major ecological functions for а period of 50 to 100 years (Shvidenko and Goldammer, 2001). Severe fires have had а significant negative impact on plant diversity. Southern species that are at the northern edge of their geographic range are particularly vulnerable. For example, in Primorsky Кrаy (Russian Federation), human-induced fires have contributed to drastic reductions in the populations of 60 species of vascular plants, ten fungi, eight lichens and six species of mosses during the past two or three decades (Shvidenko and Goldammer, 2001).

Natural fire regimes and fire-adapted plant species

In tropical forests where fires occur every dry season (savannah woodlands,

monsoon forests and tropical pine forests), tree species exhibit adaptive traits such as thick bark, ability to heal fire scars, resprouting capability and seed adaptations. The ecological importance of these annual fires on forest formations is significant. Fire strongly promotes fire-tolerant species, which replace the species potentially growing in an undisturbed environment.

Fires are а natural and important disturbance in many temperate forests, and this is seen in plant adaptations such as thick bark, which enables а species to withstand or resist recurrent low intensity fires, while less well-adapted associates perish. Some tree species in North America, notably Jack pine (Pinus banksiana) and lodgepole pine (Pinus contorta), have serotinous (late-opening) cones. While closed, these cones hold а viable seed bank in the canopy that remains protected until fire affects the tree. After fire, the cane scales open, releasing the seed into а freshly prepared ash bed. Many plant species have the ability to resprout after being burned, either from the rootstock or the stem (Agee, 1993). Mountain ash (Eucalyptus regnans), а eucalypt of temperate Australia, also requires а site to burn completely and be exposed to full sun for the species to regenerate prolifically (IUCN/WWF, 2000). Forest flammability is high in the Mediterranean Basin and most plant communities are fire prone. Quercus ilex is resistant to mild fires, and woodlands recover without any major floral or structural change (Trabaud and Lepaгt 1980). If fire is neither frequent nor intense, open cork oak (Quercus suber) forests can persist.

Fire, often with high intensity, is the major natural disturbance mechanism in boreal forests. Fire return times (the average interval of time between two fires in the same place in one ecosystem) in natural forests vary greatly, from as little as 40 years (in some Jack pine [Pinus banksiana] ecosystems in central Canada) to as long as 300 years depending on climate patterns (van Wagner, 1978). In Sweden, it has been estimated that about 1 percent of the forest land burned yearly before systematic suppression of fires started in the late nineteenth century (Zackrisson, 1977). Most boreal conifers and broad-leaved deciduous trees suffer high mortality even at low fire intensities owing to canopy architecture, low foliar moisture and thin bark (Johnson, 1992).

Some North American pines (Pinus banksiana, Р. resinosa, Р. тontico/a) and European pines (Р. sylvestris) have thicker bark and generally greater crown base and height, and old tall trees can often survive several fires. The disturbance regime of fire creates succession patterns which cause the mosaic of age classes and communities. Fire refuges exist in some parts of the forest on moist sites with local humidity, where fire may be absent for several hundred years. Fire refuges are vital to the forest ecosystem in the boreal region because many species can survive only in such areas, and then supply а seed source to decolonize the burned areas (Ohlson et а/., 1997).

In the natural forests of the northern and sparsely stocked taiga and forest tundra, particularly on permafrost sites, surface fires occurring at long-return intervals of 80 to 100 years represent а natural mechanism that prevents the transformation of forests to shrub and or grassland (Shvidenko and Goldammer, 2001).

Effects of fire on forest fauna

In forests where fire is not а natural disturbance, it can have devastating impacts on forest vertebrates and invertebrates - not only killing them directly, but also leading to longer-term indirect effects such as stress and loss of habitat, territories, shelter and food. The loss of key organisms in forest ecosystems, such as invertebrates, pollinators and decomposers, саn significantly slow the recovery rate of the forest (Воег, 1989).

Estimates from the 1998 fires in the Russian Federation suggest that mammals and fish were badly affected. Mortality of squirrels and weasels, estimated immediately after the fires, reached 70 to 80 percent; boar 15 to 25 percent; and rodents 90 percent (Shvidenko and Goldammer, 2001).

Loss of habitat, territories and shelter

The destruction of standing cavity trees as well as dead logs on the ground has negative effects on most small mammal species (e.g. tarsiers, bats and lemurs) and cavity-nesting birds (Кinnaird and O'Brien, 1998). Fires can cause the displacement of territorial birds and mammals, which may upset the local balance and ultimately result in the loss of wildlife, since displaced individuals have nowhere to go. The severe fires of 1998 in the Russian Federation led to increased water temperatures and high carbon dioxide levels in lakes and waterways, which adversely affected salmon spawning (Shvidenko and Goldammer, 2001). In areas where frequent burning occurs on а broad scale, preserving а range of microhabitats can make а substantial contribution to conserving biodiversity (Andrew, Rodgerson and York, 2000).

Loss of food

Loss of fruit-trees results in overall decline in bird and animal species that rely on fruits for food; this effect is particularly pronounced in tropical forests. А few months after the 1982-1983 fires in Kutai National Park, East Kalimantan, fruit-eating birds such as hornbills declined dramatically, and only insectivorous birds such as woodpeckers were common because of the abundance of wood-eating insects.

Burned forests become impoverished of small mammals, birds and reptiles, and carnivores tend to avoid burned over areas. The reduction in densities of small mammals such as rodents can adversely affect the food supply for small carnivores.

Fires also destroy leaf litter and its associated arthropod community, further reducing food availability for omnivores and carnivores (Kinnaird and O'Brien, 1998).

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