Conclusion

1. Conclusion here • Be sure you have clear justifiable objectives for control….not just because you think it will work! • Be sure you have data on collateral effects from control efforts • Be aware that you are embarking on a long term commitment. • DON’T enter into it lightly!!

2. Ok, it is justified • How do you do it? • First is by manipulating mortality: killing them! • Humane considerations need to be taken into account (often difficult to do). Even the most obviously deleterious species will have defenders. • The worse thing to do is make a sport of it!

3. Your set to kill • What should be the appropriate control strategy? • Return to harvest strategies: the one that was most prone to overharvest? • Fixed quota harvest! • Saw earlier that even if you have a stable population, can remove enough to cause overharvesting.

4. That is what you want! • You want to exceed the maximum sustained yield! • Add to that the instability of populations, a fixed quota harvest, set to overharvest would provide the maximum control and could even cause the population to go extinct.

5. Again, trick is how many • Because you can overharvest anywhere on the curve, setting the target kill then affects the time it takes to reach eradication.

6. Examples • Setting the kill rate of feral goats in a New Zealand park at 90%, each year would lead to eradication in 12 years. • If it was only 50% it would take 50 years!

7. Other factors? • Again, easy to say we will kill certain number of animals/year but… as mentioned, the less there are, the harder they are to get! • Adjust to hunting pressure • Adjust habitat to hard to get to places, • Adjust behavior: cows in Mexico. • Judas goats

8. Besides hunting them? • Poisons! • Whole storehouse of chemical poisons have been used on “pest” species. • Most famous: • 1) Warfarin on rodents, blood thinner, literally bleed to death. • Strychnine: used on wolves, coyotes, and anything else that eat carrion. • 1080: Sodium fluoroacetate is an organic compound and an organofluorine compound that is a well known metabolic poison. Tasteless and odorless, perfect!

9. M-44 or Coyote getter: exploding device that expels cyanide into the mouth of the animal that bites it. • Many others

10. Historic use • Used indiscriminately, spread over 1,000s of km sq. • Helped exterminate the wolf in the west. • Not so effective on coyotes! • Along with reducing populations of hundreds of other species! • Many are persistent and animal that dies from them will kill others that eat on them!

11. Current use • Much more controlled, many banned • Still use M-44s for “target” operations • Needless to say more environmental problems related to their use than any benefits.

12. Besides hunting or poisoning them? • Biological controls • Effective against insects but less so against vertebrate wildlife. • Showcase is Myxoma against rabbits in Australia. • Still not 100 %, rabbits developed immunity and Myxoma reduced virulence (not evolutionarily advantageous to kill ALL your hosts! About 20% of previous highs.

13. Other forms? • So finding a biological agent is not so great but… • If you can’t augment mortality, try the other end and reduce natality! • Controlling fertility • One way is to introduce sterile males! • Screwworms in southeast US.

14. Flood the market! • Flood the market with sterile males and females (if they only mate once) will not be successfully inseminated. • Again, useful for insects but more problematic for vertebrate pests! • Unless you can sterilize them at a distance, e.g. chemicals OR use contraceptives.

15. But… can they be effective? • List of 17 characteristics of an ideal chemosterilant program for rodents! • Highlights • Orally effective and at low doses • Permanent or long-lasting and effective both sexes • At least genus specific and inexpensive • Highly palatable and biodegradable

16. More! • No acquired tolerance or genetic resistance! • Humane: no stressful symptoms • Sufficiently stable • NOT translocated into plants, especially crops!! • Is it possible??? • Do we want to go this route???

17. Is it possible? • A lot depends on breeding systems of species. • Usually will not be controlled by action against only males. • If breeding by dominant female suppresses subordinate females, sterilization programs could actually INCREASE productivity unless you sterilize a sufficient number.

18. Even without breeding system considerations, often reduced litter production can result in increased fertility of the females that are not sterilized or receive the contraceptive! • In rabbits in Australia, female sterility had to reach 80% or more for a decline to occur! • Last note: again, long term commitment unless you can cause extinction!

19. Others? • Immunocontraception • Causing an increase in antibodies that hinder reproductive processes. • Has been used in elephants, horses, white-tailed deer, and seals. • Must be injected and often more than once in less than one year, and repeated yearly!

20. Effectiveness? • Obviously only on small populations that are easy to catch! • Other: genetic engineering! • Tie a gene that can disrupt reproduction to a low virulent virus (e.g. Myxoma for rabbits). • Problems with this!!!

21. Other than killing them or reducing reproduction? • Indirect methods: • 1)Exclusions: fences (Farmer Brown and Peter Rabbit!), chemical repellents • Can be small scale or large: Australia built a dingo proof fence spanning 8614 km!! • Keeps out other species too!! • Environmental costs high.

22. More? • Sonic deterrents: alarm calls, ultrasonic sounds, etc - Unfortunately, not very effective • Habitat and food manipulation - found could reduce red squirrel damage on young pines by air dropping sun flower seeds! - Other examples: some have been effective, others not so. Mixed results.

23. Summary • Control operations rarely meet the necessary criteria • 1) when benefits exceed the costs • 2) when “pest” species is in fact the cause of the perceived problem • 3) when control has an acceptable impact on non-target species.

24. Summary • Most clearly justifiable for exotic species • Less so for natives: Often are not pests in that there are a lot of them, perceived as such because using a resource we want. • Should we be disrupting ecosystem structure: reducing predators, or medium to small mammals .

25. Summary • Control methods far from species specific and usually a lot of collateral damage is done. • Lastly… • Considering managing and controlling wildlife species we have to ask ourselves….

26. Is this the way it should be? • If all we want is to “ranch” a single species, ok. • Lets manage them like cattle and control their predators/competitors • But is that all we want? • Is that what is good for the ecosystems that support these desired species?

27. What should our management goals be? • Sacrificing keystone species and ecosystem health for one single focused use of the ecosystem. • Remember it is the intact ecosystem that best supports the species we desire: Alaska/Africa • Not saying we should discontinue hunting, just that it should not be the only focus in resource management.

28. Original views here • America has always used the utilization of natural resources, in this case wildlife, as the focus of its resource management • But is one species management the only vision America had?

29. Remember • Started with a point in time: concern about our wildlife resources, theoretically could have gone in an infinite number of different directions. • What other directions were there?? • Return to history

30. Return to the past • Said concern started with Massive abuses of natural resources • Concern grew from this and led to 3 different perspectives on how to manage resources.

31. A look at the past • Resource Conservation Ethic. - resources to be used but just need to control the use. • Romantic Transcendental Conservation Ethic - Nature has other uses than just economic gain. - Advocated protection of large pristine areas

32. A look at the past • Evolutionary-ecological land ethic - based on ecological awareness - Nature more than collection of parts - cannot discard some based on usefulness - Also, not a temple to be worshipped

33. A look at the past • Evolutionary-ecological land ethic -Complicated, interconnected, functional - result of long term evolutionary change - We can use the system but not alter basic structure

34. A look at the past • Which of the three dominated? • Resource conservation ethic most attuned with growing country and economy. • No Brainer!! • This is what we have been talking about. • Still believe nature was to be used, just not abused, sort of….

35. A look at the past • Tried to use what we wanted wisely • Still discarded what we did not want or need. • Time when we eliminated wolves from lower 48 • “range management” use for cows

36. A look at the past • Extraction not only function of ecosystems • Other aesthetic, non extracting recreational, supportive roles. • We needed clean water, air, recreational areas, open spaces, wilderness. • Survival depended on functioning ecosystems.

37. A look at the past • This awakening a mixture of the two ethics: • Romantic-conservation- save for inherent value Evolutionary-ecological – we need all the parts!

38. A look at the past • Started talking about ecosystem integrity, biodiversity, keystone species, etc. • Saw natural systems as dynamic entities where change essential part of system • Changed from managing elements of the system to managing processes. -fire management rather than fire suppression.

39. Today • All the past laid the foundation for the next logical step: • Ecosystem Management as opposed to resource management

40. Ecosystem management • What is it • Not as easy as it may seem. Books give no less than 14 definitions!!! • Here are some of them.

41. “Ecosystem management is not just about science nor is it simply an extension of traditional resource management; it offers a fundamental reframing of how humans may work with nature” Ecosystem management integrates scientific knowledge of ecological relationships within a complex sociopolitical and values framework toward the general goal of protecting native ecosystem integrity over the long term R. E. Grumbine

42. Ecosystem approach = promoting ecological integrity while allowing human use on a sustainable basis S. L. Yaffee Ecosystem management is a concept of natural resources management wherein national forest activities are considered within the context of economic, ecological, and social interactions within a defined area or region over both short and long term An Assessment of Forest Ecosystem Health in the Southwest

43. Another • Approach to maintaining or restoring the composition, structure, and function of natural and modified ecosystems for long term sustainability • Based on Collaboratively developed vision of the desired future conditions, integrating ecological, socioeconomic , and institutional perspectives • Applied in geographical framework defined by natural ecological boundaries.

44. Common factors • Large scale • System wide perspectives • Emphasis on composition and processes • Integration across various spatial temporal scales • Participation of stakeholders/consensus decision making.

45. Dominant Themes in Ecosystem Management • Hierarchical context • Interagency cooperation • Recognition of • ecological boundaries • Organizational change • Humans as ecosystem • components • Ecological integrity • Research and • data collection • Goals set by human values • Monitoring • Adaptive management

46. What are these things? • These are the “parts” necessary for an ecosystem management plan. • Structural framework, not just definition but a visual image of what it is. • But what are its goals?

47. Fundamental Goals of Ecosystem Management • To mange ecosystems so as to • assure sustainability • To maintain ecological integrity of the • system (i.e., healthy ecosystems)

48. Sustainability • Maintenance of the potential of ecosystems to produce the same quantity and quality of goods and services in perpetuity

49. Ecosystem Goods and Services Ecosystem “goods” • Food • Construction materials • Medicinal plants • Wild genes for domestic plants and animals • Tourism and recreation

50. Ecosystem Services • Maintaining hydrological cycles • Regulating climate • Cleansing water and air • Pollinating crops and other impt. plants • Generating and maintaining soils • Storing and cycling essential nutrients • Absorbing and detoxifying pollutants • Provide beauty, inspiration and research