Relative cost effectiveness of three yellow-eyed penguin conservation measures

Transcription

1 Relative cost effectiveness of three yellow-eyed penguin conservation measures Jonah Busch and Ross Cullen This work has been supported by the National Science Foundation under grant , and by the NSF East Asia Pacific Summer Institute (EAPSI)

2 Outline Introduction: why look at conservation costeffectiveness? About the yellow-eyed penguin Research methods Effectiveness of conservation measures Cost-effectiveness of conservation measures Discussion

3 Conservation is a grand investment US$6 billion annually on nature reserves worldwide (James et al, 1999) US$1.5 billion spent in 2002 by international conservation organizations (Halpern et al, 2006) NZ$106.5 million annually on natural heritage (DOC, 2004)

4 Q: Are we getting our money s worth?

5 A: We have idea! Few well designed empirical analyses assess even the most common biodiversity conservation measures (Millenium Ecosystem Assessment, 2005) If any progress is to be made in stemming the global decline of biodiversity, the field of conservation policy must adopt state-of-the-art program evaluation methods to determine what works and when. (Ferraro and Pattanayak, 2006)

6 Why should we care? Kwing which conservation measures are most cost-effective will enable us to use existing conservation resources most effectively Demonstrating conservation effectiveness will attract new resources (untested assertion)

7 Previous analyses of conservation effectiveness and cost-effectiveness Parks (Bruner et al, 2001) U.S. Endangered Species Act (Abbitt and Scott, 2001; Ferraro et al, in press) TNC conservation easements (Kiesecker et al, 2007) Predator control (Engeman et al, 2002; Shwiff et al, 2005) NZ endangered species conservation programs (Cullen et al, 2001; Cullen et al, 2005)

8 Possibilities for effectiveness evaluation are limited No objective independent or dependent variable (Abbitt and Scott, 2001) No data on biological outcome (Kiesecker et al, 2007)

9 Golden opportunity to evaluate conservation cost effectiveness Yellow-eyed penguin conservation program Stationary, observable species Nest counts across 48 sites, 15 years Three conservation measures used at different sites at different times: Trapping Revegetation Intensive Management

10 About the yellow-eyed penguin (Megadyptes Antipodes) Large, long-lived species Endemic to New Zealand Nest on land; feed at sea Philopatric Begin breeding at age 2-3(F) or 2-5(M) Require sheltered nests in visual isolation One to two chicks a year High juvenile mortality (~80%) Photo Credit:?

11 A charismatic and valuable bird Penguins are highly appealing to humans, though yelloweyed are among the least aesthetic (Stokes, 2006) Yellow-eyed penguins elicit feelings of wonder, improve mood, and increase environmental awareness (McIntosh, 2000) Substantial NZ penguin tourism industry 126,000 overseas visitors viewed penguins in (Ministry of Tourism, 2007) Photo Credit: Penguin place

12 Threatened from all directions Terrestrial Predators (mustelids, cats, dogs) Marine Predators (sea lions, sharks) Trauma Gill nets Disease Starvation Photo Credit: tuxxie.org (Hocken, 2005) Toxic algal blooms (Shumway, 2003) Unmanaged Tourism (Ellenberg et al, 2007) Photo Credit: James D. Watt

13 Conservation status penguins in 1997 Payoff Continuum Not threatened Sparse Range restricted Gradual decline Payout value (McKinlay, 2001); IUCN redlist: endangered (BirdLife International, 2005) Most endangered of 17 penguin species DOC: nationally vulnerable (Hitchmough, 2005) 464 South Island nesting pairs in 2006 (DOC unpubl.) DOC goal: 1000 South Island nesting pairs by 2025 Serious decline Nationally vulnerable Nationally endangered Nationally critical Species Status 6 7 8

14 The penguin conservation mosaic Conservation Actors DOC Yellow-eyed penguin trust Private landowners and conservationists Conservation measures Trapping Revegetation Intensive management

15 Trapping Baited traps for stoats and ferrets Near nest sites, or set along lines Year round, or during nesting season only Rationale: reduce terrestrial mortality Revegetation With native forest species, or with nest boxes surrounded by flax Rationale: indirectly increase breeding success

16 Intensive Management Rehabilitation of sick, injured, and underweight penguins Regular monitoring of nests and traps Rationale: directly increase juvenile and adult survivorship So what works?

17 Data Dependent variable: Nest counts across 48 South Island sites, from (DOC unpubl.) Independent variables: Conservation measures used (compiled from interviews: McKinlay, MacFarlane, Goldsworthy, Sutherland, Ratz, Lalas) Control variables: Site area (McKinlay, 1997) Site location (MapToaster, 2007) Cost (Spencer, McKinlay pers.comm.)

18 Ecometric Specification it=nt/nt-1 change in nests at site i between year t1 and year t X conservation measures taken nest density y year dummy Assumption: use of a particular conservation measure is exogeus to intrinsic probability of its success; E(Xit it)=0.

19 Summary Statistics Statistic n min max median mean st. dev Year Site Population(site i, year t) Population>0(site i, year t) lambda log lambda trapping revegetation intensive management area (Ha) density

20 Regression Results Intercept (0.0232) * (0.0246) (0.0730) Trapping (0.0419) (0.0413) (0.0391) Revegetation (0.0467) (0.0461) (0.0436) Intensive Management (0.0615) ** (0.0631) ** (0.0595) Log Density *** (0.0216) *** (0.0207) Year Dummy (intercept=2006) yes 10 km site effects 3 year lag n

21 Alternate Specifications (4) Spatial autocorrelation includes a separate regressor for number of sites within 10km at which conservation measure was taken (5) Temporal lag conservation measures lagged by 3 years (time from chick to breeding adult) (6) Sea lion controls for single rogue Hooker s sea lion which has feasted massively on penguins at two intensively managed sites

22 Regression Results (2) Intercept (0.0232) * (0.0246) (0.0730) (0.0848) * (0.0725) (0.728) Trapping (0.0419) (0.0413) (0.0391) (0.0451) (0.0413) (0.0393) Revegetation (0.0467) (0.0461) (0.0436) (0.0472) (0.0457) (0.0443) Intensive Management (0.0615) ** (0.0631) ** (0.0595) (0.0641) * (0.0630) *** (0.0742) Log Density *** (0.0216) *** (0.0207) *** (0.0212) *** (0.0206) *** (0.0207) Year Dummy (intercept=2006) yes Yes Yes Yes 10 km site effects Yes No No 3 year lag No Yes No Sealion No No * (0.1111) % 14.3% 12.8% 10.1% 12.7% 21.5% n R2 IM growth rate equivalent

23 Cost effectiveness of conservation measures CEx=(N2006-Nw/o x,2006)/cx Need to kw: Actual nest # s Counterfactual nest # s Cost of conservation measures

24 Actual and counterfactual Actual: ln( it ) 0 1 X it 4 2 ln it 1 3 y it nit nit 1e ( N ( 0, 0 ) N ( 1, 1 ) X i,t 1 N ( 2, 2 ) ln i,t 1 N ( 3, 3 ) y t ) Counterfactual: nˆ it nˆ it 1e (ln( nit ) N ( 1, 1 ) X it 1 ) nit 1

25 Cost of trapping First Year Materials Each Subsequent Year $50 5 $ $ Labor $ Total per trap $50 per trap traps per hectare 0.5 traps per hectare bait and poison per trap per year traps per hectare per hectare per person-hour hour per hectare per week weeks per year $ $87.50 bait and poison per trap per year traps per hectare per hectare $16 per person-hour 1 hours per week 52 weeks per year $ 832 per hectare $832 $1, per hectare $ per hectare per hectare

26 Cost of revegetation First Year Materials Years 2, 4, 6 $ $7,500 Labor Total per plant plants per hectare per hectare $16 per person-hour 4.5 hours 50 people $ per person hour hours people $3,600 per hectare $576 per hectare $11,100 per hectare $576 per hectare

27 Cost of Intensive Management Materials Labor Total $50 $45,000 food and medicine, per nest full time ranger, per site $40,000+$50/nest

28 Average cost per site-year Trapping Revegetation Intensive Management Total Cost $1.456,667 $1,344,252 $2,619,350 $5,420,269 Number of site-years Average cost per site-year $7,141 $9,602 $45,954 $19,927 Total

29 Average cost-effectiveness (1) Simple Nests Nests gained Nests gained/site-year Nests gained/$100,000 (2) w/ density (3) w/ density, year effects (6) w/ density, year effects, sea lion actual (1.0) (1.7) (4.5) (3.1) w/o traps (7.7) (8.0) (8.4) (6.2) w/o IM (5.9) (2.7) (4.4) (3.6) w/o anything (11.7) (9.4) (10.7) (8.4) w/ traps 49.0 (7.6) 53.0 (7.9) 78.7 (7.0) 63.5 (6.1) w/ IM 30.5 (5.7) 65.4 (2.5) 62.3 (2.8) 76.0 (1.9) w/ everything 29.9 (11.7) 97.8 (9.0) (9.9) (8.1) w/ traps 0.24 (0.04) 0.26 (0.04) 0.39 (0.03) 0.31 (0.03) w/ IM 0.54 (0.10) 1.15 (0.04) 1.09 (0.05) 1.33 (0.03) w/ everything 0.11 (0.04) 0.36 (0.03) 0.37 (0.04) 0.42 (0.03) w/ traps 3.36 (0.52) 3.64 (0.54) 5.40 (0.48) 4.36 (0.42) w/ IM 1.16 (0.22) 2.50 (0.10) 2.38 (0.11) 2.90 (0.07) w/ everything 0.55 (0.25) 1.80 (0.17) 1.86 (0.18) 2.09 (0.15)

30 Discussion: Implications for yelloweyed penguin management Intensive management is most effective Trapping is most cost-effective Revegetation may have other benefits Research what makes IM effective Research marine effects on penguins Trial intensive management at more sites, while continuing trapping

31 Discussion: Broader implications for conservation Monitoring biological output is essential Unless species is critically imperiled, leave control sites and monitor these as well Keep track of costs

32 Take home message Evaluating the cost effectiveness of conservation activities can maximize penguins (or any species) provided per dollar spent. Demonstrating conservation cost effectiveness should attract new funding.

33 Thank you! Photo Credit: Dean Schneider?

34 Are treatments exogeus? Add regional dummies: change in significance of explanatory variables Add fixed effects: all explanatory variables become insignificant Difference in area between treated and untreated sites? Not significant. Difference in nest density between untreated sites which will/won t receive treatment later? No for trapping, IM. Reveg occurs at sites with significantly lower nest density. Expected sign on likely bias: If treatments are more likely to be put in place where they are expected to make a difference, then coefficients on effect of treatment are overestimates.