Conservation - PowerPoint PPT Presentation

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Conservation

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Should be good for elephants, etc (Same argument for Viagra saving Rhinos) Poaching ... kExp is revenue as in fishing. C(B) E is cost of poaching and increases ... – PowerPoint PPT presentation

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Title: Conservation


1
Conservation
2
Elongated Elephant
3
Bulte, Van Kooten
  • CITES
  • Bans TRADE in endangered species
  • Reduces Demand
  • Should be good for elephants, etc
  • (Same argument for Viagra saving Rhinos)

4
Poaching
  • Poaching model is the fishing model, but adds
    enforcement.
  • P price
  • E effort (poaching
  • B enforcement effort
  • X stock
  • F fine (punishment)

5
  • kExp is revenue as in fishing
  • C(B) E is cost of poaching and increases in B,
    enforcement. Costs of evading getting caught.
  • T E (zkEx p) expected value of punishment
  • TE is likelihood of getting cauth
  • Last element is the fine where z is a parameter
  • Notice that this term has two Es which drives
    everything

6
Zero Profits for Long Run
  • 0 kExP C(B) E TE (zkEx p)
  • Zero long run profits
  • Gives E(P, B, )
  • Point is that poaching increases in price and
    decreases in enforcement.
  • h kEx is harvest

7
Look at the Table
  • CITES goes Along with
  • DECREASED enforcement
  • Reminiscent of Kip Viscusis idea of a taste for
    danger. (Gov makes you wear seatbelts, so you
    drive faster to get in your danger quota.)

8
(No Transcript)
9
Social Planner Problem
  • 1 Elephant 4.7 cows in terms of forage
  • D(x) is foregone forage
  • W(B) costs of enforcement
  • R(x) are the existence values and tourism values
  • zTh is the value of the govt seized ivory
  • Q is total sold ivory including legal harvest and
    illegal

10
maximand
  • At each time
  • P(Q) Q R zTh cE D(x) w(B)
  • S.t. dx/dt G(x) h y
  • Assumes CITES, only a local market

11
With trade
  • Here P(Q) is world price
  • Big question is how much local price is below
    world price, even after otpimization.
  • Now problem is linear in y, so get most rapid
    approach

12
Model is really
  • Most efficient way to harvest animals
  • Poach or cull
  • Right number of animals
  • Since CITES doesnt prohibit govt from culling,
    it just reduces price.

13
Bulte and KC
  • Program this up with Zambia values and they get

14
Payoff Slide
15
So
  • Elephants are on their way DOWN, Cites or no.
  • CITES doesnt do that much.
  • Underlying reasonstrong local market, possibly
    driven by smuggling.

16
San Joaquin Kit Fox
17
ESA
  • Endangered Species Act
  • Listing
  • Take
  • Includes annoying
  • Applies to private land too
  • Habitat Conservation Plans
  • Can include a whole county
  • E.g. each acre of toad habitat you take you have
    to buy 5 acres and preserve them elsewhere

18
  • The ESA was not thought to be radical when it was
    passed. Barely any debate.
  • Court action and interaction with NEPA made it a
    very powerful tool
  • The HCP element allowed negotiation and it is now
    just another part of doing business

19
ESA
  • See Gardner Shogren
  • Most listed animals arent going to recover
  • There is far too little money allocated to
    recovery plans to make progress
  • Total value of the animals would need to be
    improbably high for it to be right for Congress
    to allocate that much money

20
Who gets listed?
  • Amy Ando sets up model where listing depends on
    things like fur
  • And also depends on pressure group activity
  • She records whether there was comment for or
    against a listing. That is her measure of
    pressure.

21
  • Payoff to a group depends on the other groups
    actions. The more pressure the other group
    applies, the more beneficial it is for the group
    to apply pressure.
  • Defines a game where the Nash non coop soln is of
    the form P(i) a bP(j) for the two groups i
    and j.

22
  • comes down to lobby is a function of furriness
    and other groups action.
  • finds that other groups action doesnt matter
  • but furriness does.

23
Bollworm
24
Pests
  • Pests are un elephants.
  • They are small
  • We want them dead but
  • We dont want to kill ourselves and everything
    else killing them

25
Pest Control
  • Cotton, veggies are a big users of pest control
  • Obvious problem is that pest control materials
    can
  • Run off and kill good things
  • Bio accumulate and kill bigger animals
  • Like ddt and birds
  • Some materials cause cancer, reproductive harm
    and so on.
  • FERPA regulates these things
  • Sunding, Zilberman, Siebert worked on costs of
    regulation in CA

26
Cotton
  • Livingston, Fackler
  • Two pests, boll wevil and budworm
  • Two controls BT cotton and pyrethroids
  • Also a refugia
  • Place where we dont use control/controls
  • Problem Bugs become immune to controls.

27
Biology
  • Assume single gene for resistance
  • x,X alleles for resistance/suspectibility for BT
  • y,Y for pyrethroids
  • x(t,i) proportion of allele in growing season t
    and generation i. Multiple generations per
    season
  • g is probability of xy etc

28
  • Since each plant has two (is diploid) alleles
    there are 9 genotype frequencies.
  • See paper for a list and their probabilities.
  • Each plant is two choices from the four possible
    xy combos with their frequencies g.
  • This makes a 9 vector of frequencies for a
    generation

29
  • Pests spend some time in refugia and some in
    cotton.
  • first generation, 95 of pests in non selective
    environment
  • then 98 of budworms in cotton
  • and so on.

30
  • Different survival rates in refugia vs in
    sprayed/Bt cotton.
  • So at end of generation, different percent of
    alleles in population.
  • Bigger refugia, higher percent of suspectibles
    maintained.

31
Problem
  • Max money
  • subject to allele dynamics
  • choose refugia size, how much to spray
  • findings use less sprayed refugia and less
    refugia all together.
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