ENCS 356 final

• ratio of cell contents to cell structure
• cell contents: good stuff
• cell structure: hard to digest

• higher crude protein, phosphorous, cell soluble levels
• lower fiber and lignin

• low
• high levels of lignification

• forbs and shrubs
• cell solubles and protein

• carbohydrates
• fats
• proteins
• minerals
• vitamins

• 1. maintenance
• 2. reproduction
• 3. growth
• 4. storage

• grazers
• browsers
• intermediate feeders

• consume primarily grasses, bulk feeders
• ex. cattle, elk, bison, bighorn sheep, horses

• mostly forbs and shrubs throughout the year, concentrate selectors 
• ex. moose, pronghorn, mule deer, domestic goats

• can adjust their diet to whatever is available
• ex. domestic sheep, caribou

• ruminants (microorganisms)
• monogastric with enlarged cecum (hindgut fermenters)
• monograstric without enlarged cecum

• pro: excellent survival under moderate quality forage
• disadvantage: intake limited by passage rate (ie. can't cope with extended exposure to low quality forage)

• pro: intake NOT limited by forage quality, can survive under low quality forage conditions
• con: problems with limited forage quantity, esp. with inefficient digestion (need to eat lots)

• 1. body size
• 2. digestive system
• 3. mouth size and shape
• 4. rumen reticular volume

• phenology
• environmental conditions
• plant growth form/species 
• plant species composition
• management

• selection of higher quality plants while feeding
• selection of actively growing plant communities

• identify and avoid high risk areas
• avoid moving livestock when hungry
• provide efficient salt (avoid cravings)
• ensure adequate water and sufficient feed to facilitate passage rates and breakdown of toxins 
• control poisonous plants (mowing, targeted herbicides)
• avoid overgrazing and forcing animals to eat plants they wouldn't normally pick

• <1% of solar energy converted to primary production
• <20% of primary production is consumed by herbivores
• conversion efficiency is <10%

• energy capture
• harvest
• conversion efficiencies

• gains per animal 
• gains per unit land area

• animal type
• stocking density
• stocking rate (timing, duration, frequency)
• location of grazing (animal distribution)

browse and palatable herbage

daily amount of forage required to meet nutrition requirements

forage demand/forage available

max level of plant defoliation that facilitates continued vigorous growth

• plant species available (and grazing tolerance)
• plant phenology
• plant vigor
• susceptibility of the site to erosion
• objectives of the rangeland manager

max number of animals that can be supported on a particular rangeland

number of animals that can be sustainably supported given current management

• max number of animals that an area can support (assumes all forage is consumed, FA=FD)
• no SUF
• no buffer to deal with variability

forage digestibility (eg. quality) limits intake

animals in poorer condition consume greater quantities of moderate to high quality forage

dietary difference allow for greater production when multiple sp. are present

• intensity
• frequency
• duration
• extent (spatial)

• plant growth
• biomass
• plant community composition
• plant-plant interactions
• biophysical properties (ex. litter)

a detailed protocol specifying the type, number, timing, and physical distribution of grazing animals

• defer or rest key species
• obtain more uniform use of forage
• increase livestock productivity
• provide opportunity for sacrifice areas to recover
• increase wildlife productivity

total period of time during which grazing could sustainably take place given the inherent conditions of the region

actual time period during which grazing takes place within a particular area

timer interval bw successive grazing periods

nonuse for a full year

delay of grazing in a pasture until seed maturity for key forage species

movement of cattle from one pasture to another on a schedule

• zero grazing
• transhumance

• seasonal suitability
• defered rotation
• rest rotation

• HILF
• LIHF
• SD
• time control

• topography
• climate (variable ppt)
• wildlife
• trees
• water distribution
• vegetation type (ex. grazing resistant)

livestock not exposed to landscape, food brought to them

• animals migrate bw adjacent land areas on concert with major phenological changes
• reflects grazing history wild animals had with landscape

• animals confined to a single pasture at low densities for the entire growing season
• pro: selectivity, max per animal weight gain, least amt fencing
• con: forage use is uneven, retrogression in over-used patches

livestock graze each vegetation type when it is most suitable

• animals not allowed on a portion of the range until after growth is well advanced 
• allows vegetation to reach maximum growth

• similar to DRG, except at least one pasture remains ungrazed all year to allow plants to produce seed
• pro: helps with livestock distribution, wildlife
• con: pastures that aren't getting rested get heavier use, reduces livestock performance bc less selectivity

• multiple herds, moderate/conservative stocking
• effective where there is year-round potential for regrowth

• designed for localized ppt events
• ex. desert systems where forbs are responsive to rainfall

• livestock are moved after utilization reaches high levels (~70%)
• long rest periods
• high utilization grazing

• livestock are moved frequently after light utilization
• shorter rest periods
• high performance grazing

• livestock are kept at higher densities and moved frequently, generally after 1 or 2 days, following the rule of "maximum of 1 bite per plant per grazing period"
• animals move based on plant growth/development

• 1. establish objectives and priorities in multi-species management
• 2. determine essential requirements for all
• 3. determine habitat potential to meet multiple sp. objectives
• 4. assess species interactions
• 5. monitor impacts of livestock management on associated wildlife
• 6. modify management (adaptive management)

grazing of 2 or more species on the same range to obtain more efficient use of forage

• modification of available forage
• alteration of vegetation structure
• disease transmission
• trampling (exposure time x stocking rate)

• alteration of plant community species over time
• wildlife injury and altered movement due to infrastructure
• water development may increase in the area of suitable habitat
• range improvements like burning, spraying, etc

• 1. wild ungulates and facultative grazing
• 2. horses and wild burros
• 3. waterfowl
• 4. upland avifauna

• strategic grazing by livestock of a given area in mid to late summer to stimulate regrowth during fall
• relies on having adequate moisture for regrowth

• 1. provide high quality winter forage
• 2. remove mature vegetation (graze later in season)
• 3. provide current year's growth (rest?)
• 4. maintain vigour (all treatments get deferment or rest)

• July 15
• gives birds time to nest 
• minimize trampling damage

• public land (regulation and enforcement)
• private land (paid hunting-fishing, nature camps/retreats, etc)

• "common use" grazing increases efficiency of animal production relative to forage available
• native ungulates better adapted to endemic diseases, landscapes, climatic conditions
• lower input costs (vet bills, breeding,etc)
• simultaneous benefits to other wildlife that use the same habitat/resources

• controversial today, used to be common practice
• best kind of management is "proactive prevention" - minimize contact with predators (guard dogs, donkeys, know when are where is risky, etc)

• can be hard to control, can sometimes be predicted
• regulated by many factors (ex. climate), most importantly can be excasperated by overgrazing

• evolutionary factors (increase survival value on habitat selection)
• behavior factors (provide the mechanism by which areas are selected)

• generalists
• some specialists tho (pandas, koalas)

• biomass regulates foraging (and therefore intake)
• composition and quality of forage
• phenology

notion that animals "know" what nutrients they ned and actively "select" forage containing these nutrients (~innate ability)

• notion that animals "learn" what nutrients are beneficial by 
• 1. mimicking their parents
• 2. post-ingestive feedback

• location and availability of water
• topography (steep slopes - avoidance or preference)
• safety (ie. risk of predation)
• time of year (summer vs winter)
• location and availability of shade (forest and riparian)
• insects
• wind (better in summer, bad in winter)
• other behavioral considerations (breeding, calving, etc)

range of ambient temperatures within which an animal does not need to expend additional energy cooling or heating itself

• strategically use topography (ex. south-facing slopes) and vegetation for thermal and safety cover
• develop a winter coat and fat reserves

• seasonally migrate with forage availability
• estivation (lowering of metabolic rate)
• ungulates experience strong seasonal patterns of weight gain and loss

• spatially preferred areas of the landscape 
• ex. valley bottoms, riparian areas
• the first choice to livestock

• areas used predominantly after primary areas are depleted
• ex. slopes, forests
• second-choice

areas ungrazed by livestock

• areas inherently avoided by animals
• excessive slopes
• heavy timber
• lack of water

• avoided through management
• fenced out riparian areas, areas with poisionous plants, critical wildlife habitat

• adjustments made to available forage when quantifying grazing capacity to account for uneven use 
• not the same as SUFS!
• MFs stress the difference between communities across the landscape

array of plants available when an animal lowers its head to feed

• diet selection
• feeding behavior

• characteristics inherent to the individual plant that elicit a selective response by a herbivore
• regulated closely by plant "avoidance" mechanisms

• proportional choice made by a herbivore in selecting one plant species for consumption over others
• varies by animal species, plant availability, time of year

• density of prey
• search efficiency
• total time spent
• total search time for all prey
• handling time per prey item
• number prey eaten during period of search time

f(x): travel to patch + searching + feeding

= bite rate x bite size

• travel time is short
• search time is high (more choosey)
• actual foraging time is short (pick the best and fill up quickly)

low bite rates, large bites

high bite rates, small but quality bites

• travel time decreases
• relative proportion of time spent actually foraging within a feeding station increases
• animal get less choosey, more opportunistic
• dont have luxury of going to higher quality FS

• total foraging time may decrease due to slower passage rates (low digestibility)
• actual nutrient intake may decrease

• water developments
• disperse salt and mineral supplements
• trail development for access (to get animals into areas like forests)
• riding (forced animal movement)
• specialized grazing systems

• soil chemistry
• GHG emissions
• local productivity

• microclimate modification (ex. litter loss -> xerification)
• soil changes (ex. soil compaction)
• competition bw plant species
• magnification of non-uniform competition

the less defoliated plant AND/OR the more grazing tolerant plant

• notion that maximum species diversity is associated with intermediate levels of disturbance (ex. grazing)
• competitive species dominate under low levels of disturbance
• only ruderal species can dominate under high levels of disturbance

the tendency of neighbouring plants to utilize the same quantum of light, ion of mineral nutrient, molecule of water or volume of space

• retrogression changes to production
• strategy of plant species to cope with fire (ex. colonizers, tolerators)
• nature of fire influences retrogression

• frequency
• intensity
• timing/season

contributes to increased woody vegetation

repetitive variation in vegetation, soil, etc with changes in slope, aspect, relief

source points for the entry of water, nutrients, salts, etc to the soil profile

points of discharge for water, nutrients, salts, etc (local, regional)

• salt levels
• nutrient levels
• effective moisture regimes
• length of growing season
• textural differences