What are the basic reasons for counting wildlife? Know a good example of each.
Are there too few?- wooping cranes
Are there too many?-deer cause damage
Are there enough? -for hunting
Is the population in good or bad shape? -comes down to numbers, environment and relationship to humans
What possible biases occur in population estimation? Know a good example of each kind.
-Conditions-less food changes behavior, weather, accessibility, vegetation
-Observer effort-cover the whole area systematically? Survey enough to be representative?
-Timing-season, time of day
-Animal Behavior-different observability, variation in distribution, hard to see
If somebody asks you to count some species, what 2 questions are the first ones you should ask them?
How important is the info, how precise does it have to be? – census, estimate, index
How much will it cost?
What are the differences between a census, a population estimate, or a population index? Under what conditions are each the most appropriate means to estimate abundance (give an example for each).
Census- complete count of entire population
-Use to count species living in open areas like waterfowl, or small populations
-Use when vegetation or topography conceals animals or when large population
Index-compare relative abundance between areas or changes in abundance from one time to another in the same area.
-seldom provides exact numbers
Know how to get a population estimate from a complete count of a sample.
Know how much of the population you have surveyed, and account for the rest
Know the basics calculations of a mark-recapture population estimate.
N=Total # of individuals in the pop at sampling.
M= # of individuals marked in 1st sample
C=Total # of individuals captured in 2nd sample
R=# of marked individuals in 2nd sample
N= (CM/R), total individuals captured in 2nd sample * # individuals marked in 1st sample divided by # of marked animals in 2nd sample
Know the assumptions needed for mark-recapture estimates.
-Everything is equally catchable
-Marks are not lost (are still tagged)
-Closed population (no immigrations or emigrations
-Marking doesn’t affect catchability (giant yellow collar is more visible, better chance you’ll see marked than unmarked)
Know the differences between inactive and active direct indices? What can go wrong in relying on such indices for population estimation?
-poop, tracks, observations of how many animals you see
Attractive (reactive, active)
-bait stations, trapping surveys, howling
Why does the indirect index of using ungulate biomass to predict wolf density work so well?
Works well because wolves are hard to find because they avoid humans, so finding their scat may be the best option
Know examples of the different kinds of biotic diversity
What are the 2 general types of information genetics can provide for conservation?
Provides an understanding of evolutionary processes (tells us what’s unique)
Identifies levels of genetic diversity
What kinds of genetic samples have been and can be collected?
Organs, blood, hair, poop
Is habitat selection innate or learned or some of both? How do we know this?
It is an innate behavior. This was proven through a study of deer mice. Woodland deer mice inhabit forets, whereas prairie deer mice inhabit grasslands. In a lab, two artificial habitats were created…one a forest and one a grassland. Prairie deer mice preferred the grassland and woodland deer mice liked the forest
Courtship behavior usually helps to reduce the chance of hybridization – what went wrong with black ducks and mallards?
The black duck population has declined because mallards have been replacing them. The ducks nested in forest related wetlands where there was no significant competition with other ducks. Hybridization was unlikely and the conspicuous plumage of the drakes gradually disappeared as natural selection favored birds whose plain, dark plumage offered protective coloration for males as well as for females. Black ducks thus evolved as “drab” mallards
What is “renesting”?
Laying a replacement clutch after an earlier nest is destroyed. Laying another set of eggs
How is a territory different from a home range?
A territory is usually part of a larger unit called the home range, an area in which an individual animal conducts its normal daily activities. The home range may be shared with other individuals, but the territory is exclusive. Territorial areas can just be a space around a single fencepost, and territorial defense can be very violent
What method do animals use to proclaim their territories?
Sometimes can be violent behavior, the headlong battering of a bighorn sheep is a good example. COMBAT, visual displays, threats, sounds, scent-urine
What is a lek?
Common dancing ground-a place where birds gather to display behavioral repertoire of dancing, calling and rattling of tail feathers.
Defense and mating occurs here.
Know the specific examples given for how conservation genetics can be used among species, within species, and among individuals.
-How are species related?-where they come from, looks, common ancestors
-What species is it?-DNA analysis of skin cells in poop
-Geographical history-classfication tree, phylogenies-shows different DNA
-Population Bottleneck-Island Grey fox-no exchange of DNA between islands
-Species or subspecies?
-Who’s breeding with who?-look at relationships, DNA of parents and offspring
-How far do offspring disperse?-pack relatedness
-How many animals are there?-collect hair
Know what a red panda, bananaquit, Darwin’s fox, and prairie chicken are.
Red panda- They tend to have overlapping home ranges in which the individuals rarely interact with each other.
Bananaquit- a bird species, scientists are not sure if there are subspecies or not
Darwin’s fox (Darwin’s zorro)-critically endangered, related to wolves
Prairie Chicken-was abundant in North America, but became rare because of habitat loss. They were all brought into captivity and eggs were taken care of. Has a mating ritual called “booming”. They defend their ritual grounds.
Know (find out) where China, Puerto Rico, the Channel Islands, Chile, Glacier National Park, and Botswana are on a map.
What is a “feedback extinction vortex” and what is the result of it?
It increases habitat loss and degradation, age specific reproduction and survival go down, causes a decrease in population growth rate, lowers effective population size, causes a decrease in genetic variation and an increase in inbreeding, and probability of extinction goes up, and increases impact of random events
Why might inbreeding be bad?
Physical defects, defective sperm, decreases survival
How can the effects of inbreeding be managed?
Bring animals into captivity and watch over them
What kinds of animal behavior are important to wildlife conservation?
Activity Patterns-avoid predators
Social Interactions-mating, raising young, protection to find resources
What is a home range and how is knowledge of home range size useful in conservation?
Home range-the area an individual animal uses for obtaining resources; food, mates, and care for its young-the place they live as adults to get resources
Useful in conservation: If resources are abundant, an animal needs a small home range whereas if they are more spread out, then the home range needs to be larger. Usually the larger the weight of the animal, the larger the home range. Fruit and meat eaters need a larger range than plant eaters
Why do home ranges vary in size among species and within a species?
It depends on the available resource distribution and abundance, weather
What is different among species that are range residents, migrants, or nomads? Why do species migrate?
Range residences live in the same place year round, can use the same resources throughout the year
Migrants spend part of one season in one place, like salamanders-usually is an annual event, long distance, and results from seasonal changes in resource abundance and distribution
Nomads have unpredictable resources, the same resources aren’t available in the same places year after year because of time and distribution. Usually large scale movements
What are territories, what kinds are there, and what purpose do they serve? Know examples.
Territory is the defense of a geographic area
Direct defense-fights, aggression-tigers
Indirect defense-displays, marks
Know the different mating systems or strategies (and examples); how they might affect sociality of a species?
Seasonal-wolves follow migratory prey, goldfinches sing in spring to defend family territory
Mating-prairie chickens have a display to attract females
Nesting-albatrosses must have enough room around their nest so that they don’t bother or peck each other. They have tiny territories but a huge home range
Feeding-tortoise has a mobile territory, wherever it is it wants to be alone
What is different among species that are solitary, live in pairs, or live in groups?What are some benefits of being part of a social group?
Solitary-Females with young, live life on their own except for mating—leopards
Pairs-monogamous-mated pairs like red foxes stay together all the time
Groups>2-have dominance hierarchies, who runs things?
Have a pecking order to maintain social standing
African wild dogs-females and males have separate hierarchies
Despotism-single ruler where everyone else is lesser—queen bee, blacked jackals
Advantages of a group:work together for resources
What does a dominance hierarchy do?
Decides who runs things and maintains social standing and pecking order so that there is little fighting
What is “despotism” and why is the naked mole rat known as a species in which this social system is rather unique?
Despotism is when there is a single ruler. Naked mole rats have a female as the queen
What is the latent heat of water and why is it important?
Latent heat of water-the heat necessary to raise one gram of water one degree C = 1 calorie..it is important because it keeps the environment stable (temp and humidity) and keeps physiology stable (body temp)
How does water get put into the landscape (3 ways)?
Rainfall, groundwater, and runoff/snowmelt
What are 3 important aspects of water quality?
Sediment-when turbidity is low, water is clear. Highly turbid areas allow less sunlight for plants to carry out photosynthesis.
Temperature-increased temp can increase productivity; don’t have to use as much energy to keep warm. But is also bad because hot waer invites diseases
Nutrients-humans can change nutrients-too little can restrict productivity. Too much can be toxic. Pesticides can affect water bodies
Know the difference between eutrophic and oligotrophic systems.
Eutrophic-enriched nutrients, hard to see through water
Oligotrophic- Low in nutrients, very clear
How does water affect animal distribution and animal populations?
Corridors-water as “connector”-roadways between different habitats used to find mates
Barriers-not every animal can swim, so water is a barrier, especially when frozen
Island biogeography-Animals that live on islands are separated from each other by water. This influences the number of species on islands-near/far to mainland (degree of isolation), large or small, etc.
Water limited environments-not much water-limits organisms, less diversity
Area of wetlands-ducks love this habitat
Precipitation and survival-rainfall at a particular time can affect survival. For example, if it is too cold and wet in the spring, turkey chicks will die. If there is medium precip and it is warmer, insects will flourish and turkeys will thrive
What are some behavioral and physiological responses or adaptations to variable water availability?
Wildebeest- Migrate, rain in February in South, grass grows, wildebeests have young, females get max nutrition and milk. Young start grazing and grow quickly. July and August-starts drying out, very dry in July, hard to find grass to eat. Migrate to Northern area where there is food, then move back in summer
Metabolic water-water produced in one’s own body after chemical reactions. Kangaroo rat gets almost all their water metabolically
Saltwater-a species challenge, many birds have evolved to be able to use it-can extract salt out and use the freshwater
Know 3 major ways that water, or lack of water, causes disturbance to the environment.
Floods-wood turtles in MA live in rivers and streams, some got washed away in a flood 20 miles down river from home. They may not be able to get back to where they came from
Drought-lack of water
Snow depth-can mean life or death-starts affecting deer’s energy balance and way to get around, takes a lot of energy
How do beavers affect water flow and their ecosystem?
succession of beaver impoundments lotic (flowing water) to lentic (still water). Build a dam so that there is winter housing. Changes surrounding environment and water. Beavers eat trees.
Name 3 ways in which we manage water for wildlife.
Potholes-humans make ponds in potholes to help wildlife
Dam removal-can be controversial because it may hurt indigenous people, but it balances things out when they are removed
Wildlife guzzlers-places where we make protected water areas for desert animals-often have tops over them and wells that pump water to the surface
What are 2 major soil “concerns”?
Desertification-turning of otherwise productive places into deserts. Caused by forest clearing and over grazing to a point where plants can’t be sustained. Can happen because of mismanagement or climate change
Erosion-loss of soil from particular areas. Caused by poor plowing, soil management, plant management, water erosion
How do animals impact soil?
Burrows-prairie dogs dig up dirt, bring it from way down to the top of the land, moves the nutrients
Sediment storage- Beaver dams-slows down sediment and everything settles out
Roosts and nutrient loads-egrets-many birds sitting in an areas, pooping amd depositing nutrients (including nitrogen) on the ground-gets into water and soil
Why are there stone walls in New England forests?
These areas used to be farmlands and walls were built to prevent the livestock from going onto the farmlands
When in the 20th century did farming practices change dramatically? How so?
After WWII-1940’s-changes in mass production-had to come up with food, there was much more effort to be more productive with agriculture, increased mechanization (machinery) and efficiency of distribution of crops
What are the effects of farming on wildlife? Give specific examples.
Direct loss-when hay fields are mowed in June, bird nests are chopped up, cover is removed
Pesticide Use-causes bioaccumulation. In small doses, they stay in the animal and add up
Fertilizer use-runoff goes into water bodies, causes algal blooms, starvation of fish, changes habitats
Clearing of hedgerows and woodlots-reduce habitat diversity-some people plow up to the edge of the road because it is potential farmland
Fall plowing-total loss of winter cover and food (stubble)-stems that are 6 inches high, serves as cover and food. Wind erosion. Siltation of remaining wetlands (soil gets into nearby areas)
In what ways can farmlands be managed or restored to provide better wildlife habitat?
Field borders-leave borders on fields instead of plowing. Will help quality of soil and wildlife, woodland, shrubs and grasses
Brush piles-for rabbits, quail, nesting birds-provides habitat
Wetlands-don’t fill in and plow wetlands-have their own purpose for water filtration, flood prevention and habitat for wildlife
Conservation tillage-Instead of turning the soil over to kill the root systems of native plants so that they don’t compete with what you plant, use a blade that goes a few inches below the soil. This will kill the roots, but it will leave them there reducing wind erosion and land erosion
What is the Conservation Reserve Program? What kinds of things does it fund?
Originally part of the 1985 farm bill. Includes milk subsidsies, food stamps, farming subsidies. In 1985 people came up with idea of conservation reserve program because farmers were going out of business. (Land prices were high, crop failure, crop prices were low. Economically troubled farm system)
Congress decied to invest $18 billion to 375,000 farmers in 47 states. Targeted 36.4 million acres, 2/3 of which were in the Great Plains
Program: we will pay you to take a large part out of your agricultural production and turn it into something that is good for wildlife. Pay you not to grow tomatoes. Pay you to grow wildlife. Make up for losses and keep farmers going
Keep land out of agriculture for 10 yrs
What is sexual dimorphism? How can it affect the habitat selection of an animal?
Sexual dimorphism is when males and females are readily distinguishable from each other. In some sexually dimorphic species, each sex tends to occupy separate habitats during the year. For example, female mountain sheep, and lambs, both more vulnerable than males, occupy steep slopes where food is of lower quality but there are fewer predators. The males select areas with higher quality food despite the greater abundance of predators
What is imprinting? What two purposes does it serve?
Imprinting is a type of permanent learning that takes place during a relatively brief period of responsiveness early in the life of some animals.
The two purposes it serves are:
1-establishes a bond between mother and offspring
2-establishes a means by which males recognize the females of their species
How is migration different from dispersal?
Migration is the simple act of moving from one spatial unit to another, across land and water
Dispersal is when young animals leave the home range where they were reared and wander to new locations
What is a flyway?
Lincoln classified the migratory routes for birds across North America into 4 flyways-Mississippi, Central, Atlantic and Pacific. Each flyway corresponds to a major route followed each year by millions of waterfowl and other birds.
What is a hibernacula and how does it relate to snake migration?
Hibernacula-winter dens for rattlesnakes. They migrate seasonally between these hibernacula and their breeding and foraging areas.
Describe 2 different kinds of migratory behavior of some mammal species. How are they the same/different?
Several kinds of bats spend the summer in New England, but hibernate in Winter in Massachusetts, CT, and VT
Sperm whales move around in response to availability of their primary food, cuttlefish, which abound where cold and warm waters mix. Females and young bulls rarely leave the tropical waters in Africa and South America, but in summer the older bulls venture as far as the Bering Sea and then return again in the autumn to join the females in the warmer oceans
Do lemmings really migrate, or do they just disperse?
They do migrate, but for short distances down mountainsides from their breeding grounds. They migrate individually from high population densities to low population densities
Who manages migratory animals and under what authorities?
The Federal Government, under the Migratory Bird Treaty Act (1918), and the Ramsar Convention (joined by US in 1987)-promotes conservation of wetlands. International Whaling Commission
What are the major forests in the world?
Deciduous, coniferous, throughout the Northern globe
How recently did the U.S. government get serious about forest land protection (i.e., protect more that 100,000 km2 of forestland in the form of National Forests)?
Not until the early 1900’s, they were enlarged 8x by Teddy Roosevelt and Gifford Pinchot
How recent is concern about wildlife management on forested lands?
1950’s-wildlife biologists were hired
Who owns forestland in the Southeast, the West, and Massachusetts?
Southeast-Mostly privately owned, but also owned by corporations and individuals
West-Mostly federally owned, some private
Massachusetts-Mostly private, some public, some forest industry
Define succession, silvaculture, sustained yield management, even-age and uneven-age management, and rotation time.
Succession-replacement of one plant with another-refers to both plants and wildlife
Silviculture-regeneration, tending, and harvesting of the forest
Sustained yield Management- “constant” supply overtime
Even aged management-clearcutting, shelterwood cut, cut all trees in a patch
Uneven age management-selective vutting, cut some but leave others
Rotation time-the number of years between the time a tree or stand is cut and the time it is replaced by another harvestable tree or stand
How is clearcutting good for wildlife?
Leave some snags and some big trees, provides lots of browsing area, shrubs begin to provide cover
What are snags and why are they important to wildlife? How about deadwood/woody debris?
Snags are dead or mostly dead standing trees. they are used for nesting, living in cavities, and perches
Dead/woody debris-used for cover, homes, finding food, insects
What role does fire play in wildlife conservation?
Changes landscape dramatically, and wildlife
Get rid of old trees and allow new trees to grow to lessen competition
Why manage forests in Massachusetts?
Maintain species abundance-birds, keep the system going
Know tree size classes.
seedlings <1" dbh
sapling/pole (firewood) 1 9" dbh
sawtimber (boards) >9″ dbh
Are most bird and mammal species habitat generalists (use more than 1 forest successional stage) or specialists?
Most are generalists.-use more than 1 type
Predators often select individual prey animals that show some oddity in color, behavior, or location.” Explain how bluegills, rock doves, mice and horses are examples of this.
Bluegills that were infected with parasites that produced normal coloration are ata greater risk of predation by bass than are normal bluegills
When goshawks hunt in a prey population dominated by white birds, most of the kills are dark colored rock doves. Conversely when the dark rock doves were more common, the goshawks attacked the small percentage of white birds
Conspicuous mice on a dark background are more vulnerable than those where contrast is lacking
Mountain lions select brown colored young horses, which were underrepresented because they resembled mule deer
Why does “a mountain live in mortal fear of its deer”?
Because the deer browse the mountain until it is empty of plants
What does the Lotka-Volterra Model illustrate about predator-prey systems, i.e. what does it illustrate about how the predator and prey populations interact?
Lotka and Volterra developed equations that assume a certain potential rate of increase for the prey population in the absence of predators and a decline in predator populations in the absence of prey
predators have more food when prey populations are high, hence the number of predators increases. the prey population declines. As the prey declines, the predators find less food and their death rate increases until there are so few predators that prey numbers again begin to increase
What is the difference between additive and compensatory mortality?
Mortality factors such as disease, starvation, and predation frequently tend to be compensatory. For example, If a certain percentage of animals dies from predation, then the percentage of animals dying from starvation will be diminished in comparison to that of a predator free population. Conversely, if a certain percentage starves to death, then a smaller percentage of animals will die from predation. Such an effect is said to be compensatory-that is, one cause of mortality largely replaces another-whereas additive mortality involves summing the percentages dying from each cause of death
What are “functional” and “numerical” responses in predator-prey systems?
Functional response-the tendency to eat more prey as its availability increases
Numerical response-when the numbers of predators increase with an increase in the density of the prey population
What are Leopold’s 5 factors that must be considered in piecing together the predator-prey puzzle?
1-density of the prey population
2-density of the predator population
3-characteristics of the prey, including reactions to predators, and nutritional condition
4-density and quality of alternate foods available to the predator
5-characteristics of the predator, such as its means of attack and food preferences
Who are the Hamerstroms?
Frances and Frederick Hamerstrom are field biologists. Lived in the 1900’s. worked with prairie chickens, many other birds
Know how the 10-year snowshoe hare cycle works.
A decline in hare population begins when high numbers of hares produce a shortage of aspen twigs and other winter food. The food shortage results in high mortality of young hares, lowered reproduction the following summer, and consequent reduction of the size of the hare population. The predator to prey ratio thus increases so that owls and lynxes exert a greater effect on the hare population by killing a larger proportion of those that remain available. As hares become scarcer, the predators turn increasingly to ruffed grouse, thereby initiating a decline in grouse population. Eventually the shortage of both species of prey diminishes the size of the predator populations, mainly from emigration and reduced survival of immature owls and lynxes. The scarcity of hares permits regeneration of the vegetation and increased reproductive success in the remaining population. When the number of hares reaches the point where demand for food outstrips the supply of vegetation, the hare population begins to decline and another cycle starts.
How have predator control experiments clarified whether or not predators control prey populations?
It cannot be answered clearly. In some situations, predators do control prey populations, while in others they do not. Predation remains just one of several factors that brings death into balance with birth.
What are four methods used to control coyotes (in reference to predation on domestic animals)?
1-trapping-with steel leg hold traps using bait or scent
2-den hunting-in which pups are killed at den sites
3-shooting-in chance encounters or by luring with distress calls, effective by aircraft
4-poisoning-with any of several substances
What has been the effectiveness of coyote control on reducing sheep mortality? (see the Wagner (1972) data cited in the text).
45% of ranchers reported no loss of lambs to coyotes, and 67% reported no loss of adult animals. But coyotes claimed more than 20% of the lambs on 10% of ranches
As of 1978 what were the most and least accepted methods of non-lethal and lethal control of coyotes? How do you think things have changed since then?
What is Wallace’s line? Explain how the speciation of Darwin’s finches occurred.
Wallaces’ Line is a zoogeographical boundary that coincides with a deep trench in the seabed between the small islands of Bali and Lombok in the East Indies. It remained an effective barrier to faunal dispersal even when sea levels were lowered during the glacial ages of the Pleistocene. Conversely, the islands between Bali and the Asian mainland were surrounded by much shallower seas; the islands joined as a contiguous landmass with Asia when the Ocean receded. Faunal dispersal occurred between the mainland and the islands up to and including Bali but not beyond. The gap between Bali and Lombok still marks the terminus for the Oriental fauna.
Darwin’s finches-arrived from South America and evolved into 14 species. The water between the islands was of sufficient distance to allow time for the development of reproductively isolated populations before additional colonizers invaded from other islands in the Galapagos.
How have studies shown that rainfall or snowfall are related population changes? Give examples.
For many animals, successful breeding is directly or indirectly related to water, usually in the form of precipitation.
Cottontails-The harvest of cottontails on the first day of hunting was related to the combined amounts of rain falling during March and September. Higher rainfall during these months diminished the number of cottontails killed per hunter.
Ducks-depend largely on semipermeable wetlands for nesting habitat-without rainfall the potholes can’t fill up and breeding is reduced.
Bobwhites(bird)-drought reduces number of juvenile quail per female
What causes the weather event known as “El Nino”? What are some consequences of it?
El Nino is caused by changes in thermal structures of the Pacific Ocean at the equator. Occurs about every 4 to 5 years, during Christmas. The warm water in The eastern Pacific may unleash droughts, floods, and other powerful forces. Surges of warm water, Kelvin waves, flow toward the western coast of South America. Normally, there is an upwelling of nutrient enriched cold water off the coasts of Peru and Ecuador-but this is interrupted and the food web collapses
El Nino may disrupt socioeconomic conditions as well as biological conditions.
The ‘reservoir effect’ is a result of human activities, not natural flooding events, true or false?
Reservoir effects occur naturally on many wetlands, which are maintained by precipitation that is characteristically unpredictable. the areas undergo frequent but irregular wet-dry fluctuations. there is seasonal flooding in river-bottom forests.
What are two benefits of green-tree reservoirs?
1-the trees are not killed, so timber resources are not lost
2-the acorn crops important as foods for wintering waterfowl remain available each year regardless of rainfall
How do beaver ponds affect trout populations and waterfowl habitat?
Significantly more, and larger trout occur in beaver ponds. Access to spawning habitat is lessened
Beaver impoundments often provide nesting habitat for waterfowl. Dams provide cover and water, good composition of cover types, food resources, no humans, etc.
What are ‘gator holes’ and how do they affect the ecology of the Everglades?
Gator holes overlay natural depressions in the limestone floor of the Everglades. Alligators clear marsh vegetation from the depression and then move the debris to the rim, forcing a pool surrounded by a levee of plants and mud. Willows and bald cypress invade the rim. Understory vegetation of the levees consists of grasses, ferns, and other shade plants. The vegetation brings diversity lacking in much of the Everglades.
Gator holes become miniature refuges of freshwater during the winter dry season, maintaing creatures dependent on water
How do oil spills, pits and sumps affect birds?
When covered in oil, are killed-lose insulation when plumage is fouled with oil, oiled birds usually stop feeding and must draw on their body reserves. they eat oil as they try to clean their plumage
oil pits and sumps
Birds mistake the oil for water-they sink and disappear
How do wildlife interact with sewage treatment plants?
Construction of sewage treatment plants often creates wildlife habitat for a number of aquatic species. The waterfowl are attracted by the abundant invertebrate food supplies available in nutrient-enriched ponds. A good place to raise young
What is the source of acid rain and what deadly elements does it contain?
Combustion of fossil fuels, particularly coal, leads to chemical reactions in the atmosphere. Acids form when sulfur dioxide and nitrogen oxides released from smelters, power plants, or other industrial installations combine with atmospheric moisture. Environmental damage occurs when the moisture, now infused with sulfuric acid and nitric acids, falls as precipitation
How are wildlife affected by acid rain?
Acidification has resulted in a decrease in the survival, size, and density of fishes in lakes. Limits egg survival, there is skeletal deformity
Fish eating birds are affected. acidity eliminates clams and snails, each an important source of calcium for birds during egg laying
How does channelization affect riparian ecosystems?
Channelization-straightening streambeds to reduce floods
-often destroys riparian zones bordering the stream and so alters the size and composition of wildlife communities associated with streamside vegetation. It reduces the number of occurring species. Destroys habitats and food
List some water developments that have proven beneficial for wildlife.
-flood prevention lakes (impoundments of various sizes designed to reduce floods by confining excess water in the upper reaches of watersheds
-seeps to collect water
What are some factors that need to be considered when designing artificial water sources for wildlife?
The damage that could be done, the way the animals will respond, existing habitats, soil, climate
What was the experimental flood of the Grand Canyon in 1996?
A large volume of water was released for one week from Lake Powell into Grand Canyon. Because flooding amplifies sediment transport, one of the objectives of this experiment was to rebuild sandbars along the margins of the Colorado River in the GRand Canyon and thereby rejuvenate backwater habitats for humpback chub and other native fishes. When normal dam operations resumed, the recreated habitats steadily decreased in area.
Give some examples of the ways in which soil influences the distribution, abundance and health of wildlife?
-animals that tunnel depend on soil features for the integrity of their tunnels
-soil structure influences the distribution of fox dens
-Kingfishers need soil with mostly sand and some clay for their nesting burrows. The sand aids excavation and improves drainage
-calcium designates pheasant populations
-sodium salts are preferred, but calcium and magnesium salts also attract big game
-better quality soils support larger-bodied animals
How does the location of former glaciers in N. America still affect some wildlife today via the soil?
Successful populations in the north central states largely coincided with the area covered by the Wisconsin Glacier. Available calcium seemed the most important mineral in relation to self-maintaining pheasant populations
What are salt licks and which elements are obtained from them?
salt lick-a place where animals go to lick salt from the ground. They are natural formations of mineral bearing soils. Include sodium, calcium and magnesium
What animals may be attracted to salt on roadways?
Moose-in Ontario, Canada. from salt applied to de-ice roads
The rich soils of tropical forests provide insurance that deforested areas will rebound quickly with new growth, true or false?
FALSE-After a few short years of crop production, the deforested soils lie wasted and capable of sustaining little more than poor-quality pastures where cattle can forage. little chance that successive processes will again transform the area into tropical rainforest
List 4 ways that tropical deforestation could be slowed down.
-the chinampa system-intensively uses lands already cleared, thereby haltering expansion into additional forest
-small canals around each farm plot provide irrigation and can grow aquatic vegetation, fish in the canals
-agroforestry-farms of both trees and crops
-debt for nature swaps-conservation groups pay the debts of foreign nations in exchange for the protection of rainforests
What are some of the symptoms of desertification?
-declining water tables
-salinization of soil and water
-reduction of surface water
-high rates of soil erosion
-degradation of native vegetation
Most large deserts that are present today, including those of North Africa and the Middle East were formed naturally, true or false?
What are the causes of most cases of desertification?
Desertification develops in times of drought where already vulnerable arid and semiarid lands have been abused. These lands then permanently degrade into deserts
List some ways in which animals move soils.
-pocket gophers transport soils to the surface
-Invertebrates mix soils-earth worms
-Rodents store plant materials below the soil’s surface
-Hooved animals compact soils
How do cattle affect soils differently than native ungulates?
ungulate (hoofed animal)
Native cattle compact soils and may prevent percolation of water. DOn’t cause soil erosion
cattle are herded in tight units because of predators. Intensive herding thus concentrates grazing and contributes greatly to soil erosion. Delicate plant communities are pawed and the protective layer of plant cover is destroyed
What ecosystem (animals and their mutual associations) did bats create in an abandoned mine in Sonora, Mexico?
3 species of bats pooped in a mine and created a cave of feces. Cockroaches east the feces, frogs live in the water pool and eat the cockroaches, sunlight entering the mine supplies photic energy for the aquatic plants and food for tadpoles. Freshwater cave crabs feed on dead bats and frogs. Snakes, raccoons and turtles enter the cave and eat as well.
What and when were agriculture’s four revolutions?
10,000 years ago-wild plants were domesticated in northern China, Mexico, Iraq. WIldlife also evolved
15th century-the product of exploration and discovery (COlumbus, Magellan) Sea routes and trade, worldwide exchange of agricultural commodities. Corn nd potatoes were introduced into Europe
Industrial Revolution-1760-1840-Steam power, fossil fuels, mechanization. COtton gins, reapers and other equipment replaced human and animal labor, increasing production. Railroads carried farm products far
Technology founded the 4th revolution-scientific progress in chemistry and genetics brought herbicides, fertilizers and insecticides. Hybrid crops, increased food yields
What was the Conservation Reserve Program? What did it do?
The CRP was part of the Food Security Act passed in 1985. Farmers voluntarily remove highly erodible land from production for 10 years under agreement with the US Department of Agriculture. Farmers must maintain permanent cover on the CRP land while the government guarantees the landowner a rental payment annually for 10 yrs and shares up to 50 % of the cost of establishing the cover
What management techniques seem to reduce crop depredations?
Depradation-damage to crops
Combinations of scaring tactics, feeding stations, and lure crops
Give two examples of how crops can be lethal to wildlife.
Soybeans are grown in many areas frequented by Canada geese, and at times, these impact in the esophagi of feeding birds. SOme die suddenly and others starve slowly when the impacted soybeans prevent passage of food into the stomach and erode the lining of the esophagus.
Aspergillosis is a fungal infection of the respiratory tracts of birds exposed to molding crops. Wood ducks that fed on recently flooded corn were affected
What type of land experiences the greatest soil loss from wind and water erosion?
What are some unforeseen results of pesticides?
Reducing biological diversity, interrupting food chains, modifying energy transfer, reducing the quality of soil, water, and air, and lessening the stability and resilience of both natural and managed environments
What are the general effects that pesticides have on ecosystems?
environmental damage, ecological disasters, poison wildlife
What are shelterbelts, odd areas, and conservation tillage?
shelterbelts-(windbreaks)-were adopted as a means of protecting soil against wind erosion. They are ecological units offering opportunities for managing game and nongame in otherwise treeless environments
odd areas-small areas unsuitable for cultivation-may be important areas for wildlife
conservation tillage-a newer concept that overcomes wind and water erosion. Stubble and other reside from the previous crop are left on the soil surface, thereby forming a cover that reduces wind and water erosion
What percentage of the world’s land area do rangelands occupy?
47%-are unsuited for cultivation but produce forage for livestock and wildlife
How does moderate grazing stimulate regrowth of grasses?
Growth in grasses is initiated upward from the base. when upper leaves are grazed, grasses generate new herbage from the stem remaining near ground level, replacing the consumed tissues. Without grazing, many grasses mature into rank vegetation
What aspects of foraging does the “animal unit” fail to recognize?
The AU does not consider different types of foraging pressure; that is, some species might require browse, whereas others subsist primarily on grasses
What are the three main mechanical methods of range management?
mowing-reduces canopies of shrubs and trees but leaves the root systems alone
chaining-removes cover, dragging heavy chains behind bulldozers
root-plowing-reduces cover of woody vegetation, a heavy blade is towed through the soil, severing brush below ground
How are herbicides, fire, and fencing used to manage rangelands?
aerial applications are used to reduce undesirable plants on rangelands
fire favors grass over woody plants-used to maintain grasslands
fencing controls livestock movement without need of herders, prevents intermixing of separately owned stock, and amy promote the proper usage of forage when herds are manipulated between pastures
Overgrazing not only imposes costs to the environment, but may also be financially costly to cattle owners. Explain why?
As vegetation retrogresses with continued overgrazing, crucial soil and water relationships also fail, ultimately reducing the rangeland’s carrying capacity for grazing animals, even after stocking rates are lessened.
How does grazing affect trout habitat? What are some of the solutions?
Grazing near fisheries damage aquatic and streamside communities. Undercut banks, overhanging vegetation, and other conditions desirable for trout were damaged. Stream became 5x as wide, and only 1/5 as deep, warm shallow water and not good habitat
How does burros, an “exotic invasive species”, affect the rangeland ecosystem?
Burros typically concentrate in dry washes where their heavy utilization of forage is pronounced. The heaviest browse occurred near permanent water and the lightest further away. Riparian habitats receive heavy browsing pressure during summer months
they remain in good health despite seasonal differences and can survive in sparsely vegetated areas
What is the basic principle of game ranching?
Native species are far better adapted to local conditions than are domestic livestock. In other words, attempts to raise cattle sheep or goats would be better foregone to raise native species
How do native species compare to exotic species in their efficiency of range forage conversion to protein?
Native species convert range vegetation into meat more efficiently
Jack Ward Thomas got his Ph.D. in wildlife here at UMass; who is he?
He is the former chief of the USDA FOrest Service. he reduced logging on national forests and was president of the Wildlife Society. Loved natural resources
What are life-form associations?
Thomas developed a systematic approach, using categories of breeding and feeding habitats of the various animals used to assess the benefits of each forests management practice
What needs to be considered when assessing the benefits of clear cuts for wildlife?
the kind of wildlife, how large the clear cut area will be, and how long a period of time it will take for reforestation
What is a snag and why are they important to wildlife?
Dead and dying trees which provide nesting, feeding and perching sites for birds
What is a nurse log?
dead and down woody material which provide a base for growth of new trees
What are two adaptations of certain plants to fire?
Longleaf pines’ sprouting seeds produce a root and a ground level bud(1), from which sprouts needles. For 7 years, the sedling remains in this grass stage while storing nutrients. A ground fire at this stage of development burns the needles but doesn’t destroy the root or bud. Thereafter, the young tree draws on nutrients stored in the taproot, and grows and develops thick fire resistant bark(2)
What are the consequences of fire suppression in certain habitats?
Long periods of fire suppression im longleaf pine stands permits large accumulations of combustible ground litter, so the fires that eventually occur are larger and hotter and the fires destroy all species, including the pines
Generally sets back succession
Is a 100-year rotation of timber harvest in old-growth forests successful in simulating the ecological characteristics of the natural stand?
No, they don’t attain the characteristics of present old growth stands
How can forest management create habitats ideal for ruffed grouse?
abundant aspens including saplings, pole-size trees, and mature trees are ideal ruff grouse habitat. Forest management can create these conditions by clear cutting in a pattern in which a patchwork of 4 age classes of aspen are present
What are inbreeding and outbreeding depression?
results from matings between siblings or other members from the same family group and the occurrence of extreme homozygosity (many similar genes)
matings among individuals with diverse genetic backgrounds which may lead to reduced fitness
What were the characteristics of Florida panthers that seemed related to inbreeding depression?
lower semen volume, more abnormal sperm, reduced sperm motility, only one testicle in the scrotum