Wildlife Damage Test #2 (Fertility Control)
What are the 2 ways basic ecological models of population
growth indicate to decrease equilibrium density?
- Increase environmental resistance
– Decrease biotic potential
How do you change equilibrium density?
- Increase death rate
– Decrease birth rate
What are the two stages of fertility control?
-Prevents egg from being fertilized
- Kills embryo
What are different methods of fertility control?
– Mechanical and surgical
– Endocrine Disruption
What are some characteristics of ideal contraception?
- Effective in single dose
- No hazard to nontarget species
- No harmful side effects
- No effect on social behavior
What are some reasons to use contraception?
- to reduce wildlife populations
- Reduce fertility of specific animals
What is the best way to reduce the population in a polygynous species?
Sterilize dominant males
What is the one circumstance that allows for the population to be reduced in a monogamous species?
If pair bonds are long-lasting
What is the one circumstance that allows for the population to be reduced in a territorial species?
If territories maintained for long time
Which species is more suited to fertilization control than lethal control?
Fertilization control is not always considered most _______ method of
What are some drawback to fertility control?
- Adverse side effects
- Adverse effects to current offspring
- Lengthen breeding period
- Could effect non-target species
What is done during the surgical method of fertility control?
The removal of reproductive organs.
What is done during the mechanical method of fertility control?
Males--Devices that block sperm passage
What are the advantages and disadvantages of mechanical or surgical methods of fertility control?
Advantage: single treatment, permanent, no
risk to non-target
Disadvantage: surgery usually impractical
What are some methods of fertility control based on
What is the disadvantage of using steroids as a method regarding the endocrine system?
Difficult to administer, side effects, high cost (usually impractical).
What are some advantages and disadvantages to administering GnRH regarding the endocrine system?
Advantages: Rapidly metabolized (no environmental problems or
secondary poisoning + Reversible
Disadvantages: Suppress reproductive and social behavior +Prolong or delay breeding season + Little research
What happens during the Immuno-contraception method of fertility control based on the endocrine system?
Vaccine given to stimulate immune system to produce antibodies that destroy own hormones or gametes.
What are the advantages of gamete based immuno-contraception?
- to affect on reproductive or social behavior
What are the disadvantages of hormone based immunocontraception?
- affected reproductive and social behavior
- side affects
What are the different delivery methods of fertility drugs?
- Remote delivery systems (darts, bullets, etc.)
- Oral delivery (baits)
- Vector delivery
- Controlled Release Methods (mechanical pump, etc)