Fire’s Effects on Wildlife
description
Transcript of Fire’s Effects on Wildlife
![Page 1: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/1.jpg)
Fire’s Effects on Wildlife
![Page 2: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/2.jpg)
Direct Effects• Few studies, marked re-capture approach ideal
– Body size and mobility, i.e. burrowing, influence direct mortality
• Life cycle stages are impacted differently• Depends on fire regime
– Frequency, intensity, extent, and season– Extent-small area, greater ability to repopulate
• Must look at populations rather than the individual
![Page 3: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/3.jpg)
Indirect Effects
• Fire severity and resulting successional patterns dictate wildlife habitats and the effect on wildlife
• Importance of fire regime
• (+/-) Consumer response is species dependent
![Page 4: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/4.jpg)
Mechanisms of post-fire population change
• Population response to fire regulated by:– Availability of food resources– Changes in cover– Movement of populations in/out of
burned/unburned areas (migration, immigration)
![Page 5: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/5.jpg)
Understanding the Consumer Response to Food Resources
• Fire alters production, species availability, and food quality
• Migration and immigration • Short term effects
– Deer mice in prairies or grasslands• Some mortality during fire may decrease populations • Adapted to postfire environment: insects, wind-
dispersed seeds, soil seed bank• Populations may increase several-fold in burned areas
![Page 6: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/6.jpg)
Understanding the Consumer Response to Food Resources
• Alternatively, shift in food sources– Ex. Australian eucalypt forest
• Bettongs exploit fire adapted fungus
-- Ex. Primates in Borneo shifting food sources
• Flowers and fruits unavailable• Shift to foliar/herbaceous vegetation and caterpillars/larvae of wood boring insects
![Page 7: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/7.jpg)
Consumer Response and Food Quality
• Pulse of higher quality new growth– Increase in protein (nitrogen content) in new
growth– New tender shoots with greater digestibility– Increase in population growth rates
• Ex. Domestic grazers
![Page 8: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/8.jpg)
Changes in Cover• Burned vegetation results in drastic change in both physical and
thermal cover– Grasshoppers – decline after fire, require a well-developed litter layer
for habitat– Earthworms – found 10-20 cm below soil surface, direct affects only
with severe fires; may increase postfire due to increased plant productivity
• Physical protection from predation– Structure provides protective habitat– Affects visibility
![Page 9: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/9.jpg)
Red-cockaded woodpecker in loblolly pine forests
• Forage behavior of woodpeckers: – Foraged at greater heights in areas of tall and dense
midstory vegetation– Concentrate foraging activities in forest stands or
openings with reduced midstory vegetation• Fire regime in Loblolly pine
– Fire-maintained, frequent surface fires – Changes in fire regime: fire suppression
![Page 10: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/10.jpg)
TTYP• Why do red-cockaded
woodpeckers require fire in order for long-term survival of their populations in loblolly pine forests?
• What are the specific mechanisms?
![Page 11: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/11.jpg)
Mortality of Cavity Trees
• Disturbance by prescribed burning, thinning, winds, and southern pine beetle increases cavity tree mortality.
![Page 12: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/12.jpg)
Balancing Protective Cover and Food Availability
• Tallgrass prairie example• Bird response
• Increase in seed/insect availability• Decrease in cover, nesting habitat, and predator
protection
• Small mammal response • Some small rodents, i.e. prairie vole, are small
navigate litter layer and find seed• Other larger rodents, prefer burned area with
easier seed access
![Page 13: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/13.jpg)
Structural Diversity• Interspersion of food resources and
cover
• Positive or negative effects depending on the severity and extent and the wildlife considered
• Reduced habitat heterogeneity by large extent, severe fires
![Page 14: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/14.jpg)
Example: Structural Diversity• Habitat diversity
and complexity, each supports a specific faunal community– Ex. Snags
important for birds, mammals, reptiles, amphibians, and invertebrates
![Page 15: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/15.jpg)
Plant Succession and Animal Response: moose & caribou in boreal forests
• Discuss the following questions:– How are moose/caribou affected by fire?– How would you design a management plan to
manage for moose OR caribou?– How would you design a management plan to
manage for moose AND caribou?
![Page 16: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/16.jpg)
Plant Succession and Animal Response
• Browsers in North American boreal forest– Caribou eat lichen, slow
growth, easily burned• Caribou in late
successional – Moose eat woody
resprouts (birch, aspen)• Moose in early
successional
![Page 17: Fire’s Effects on Wildlife](https://reader033.fdocuments.net/reader033/viewer/2022050721/568167c8550346895ddd1667/html5/thumbnails/17.jpg)
Structural Diversity and Patchiness• Mature cover provides
refuge for migration• Adjacent high quality
growth in burned areas
• Mosaics of food resources and cover create structural diversity– Ecotones - boundaries