Applications of ecological theory to biodiversity conservation: some examples

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1 Applications of ecological theory to biodiversity conservation: some examples Mark C. Andersen Department of Fishery and Wildlife Sciences New Mexico State University

2 Co-investigators, etc. Michael J. O Farrell Dipak Mahato Harold Koopowitz Alan Thornhill Bruce Thompson Ken Boykin

3 The basic question To what extent can theoretical ecology provide guidance on real-world, 21stcentury conservation problems? OR Can theoretical ecology be practical?

4 The examples Reserve design Estimating extinction rates and/or taxon-level or regional vulnerability Assessing and managing multiple threats to multiple species in a landscape context

5 Issues in reserve design Relevant theory: stochastic demography Goal: Ensuring persistence of target population (s) Basic results/principles: Few, other than more is better and every case is a special case Feedback from practice to theory: Not much

(s) Basic results/principles: Few, other than more is better

6 Example: Stephens Kangaroo Rat The point: picking an optimal subset of an available set of parcels of land

7 Example: California spotted owl Andersen & Mahato, 1995, Ecol. Appl. 5(3): The point: Choosing between alternative management strategi when those strategies have different land-use implications

5(3):639-647 The point: Choosing between

8 A broader context: demographic sensitivity analysis Very effective way to evaluate demographic effects of alternative management strategies: Crooks, et al Cons. Biol. 12(4): Heppell Copeia 1998 (2): Heppell and Crowder Bulletin of Marine Science 62(2) (Origins in life-history theory.)

Cons. Biol. 12(4): 889-895 Heppell. 1998.

9 A challenge: Incorporating economics Static: Stephens Kangaroo Rat example Dynamic: What if persistence is not the appropriate objective? What if minimizing the long-term costs of management interventions is the appropriate objective? Rare (Ralls and Starfield, 1995, Cons. Biol.9: )

What if minimizing the long-term costs of management interventions is

10 Looking ahead Economic dynamics and criteria Improving feedback from practice to theory Decreased reliance on canned programs

11 Deforestation and biodiversity Species-area approach Distribution profiles approach

12 Deforestation and Biodiversity: Species-area approach S original = c (A original ) z S new = c (A new ) z

13 Deforestation and biodiversity: distribution profiles Frequency distribution of the number of sites from which 5136 species of Neotropical plants have been recorded

14 Predicting extinctions One-time deforestation episode: = = y n n n t c b a E 1 Continuing deforestation: t t t E a a = +1 and = + + = + + = y n z n z t z n x x n t n t t n c b c b b b 1 1, 1,, 1, E: # of spp. Going extinct a: # of extant spp. b: bins (categories) of distribution profile c: deforestation rate

n x x n t n t t n c b c b b b 1 1, 1,, 1, E: # of spp.

15 Predictions of the model Cumulative extinctions over time. A: constant fraction of habitat lost each year B: Constant amount of habitat lost each year Types : Classes of d.p.s in order of decreasing skewness

$A: constant fraction of habitat lost each year B:$

16 Recommendations Focus attention on regions (for conservation planning) and taxa (for systematic study) that contain large numbers of endemic species Examine ecological and evolutionary traits that may influence the shape of a taxon s distribution profile

numbers of endemic species Examine ecological and evolutionary

17 Looking ahead Added spatial realism Theory development (determinants of distribution profile shape) Useful recommendations for regional conservation planning - relation w/ GAP

18 Risks to species Spatially explicit models of risks to species of concern on military installations (White Sands Missile Range and Fort Bliss) Goal: convert spatial information about land use and habitat characteristics into maps of risk to individual (and multiple) species

Fort Bliss) Goal: convert spatial information about land use and

19 SAR Analysis Procedure Identify comprehensive set of risks Identify feasible management alternatives Assign impact scores for each risk source to each species Map risk scores across region for each species/management combination Map species actual/potential density Produce combined/weighted map

source to each species Map risk scores across region for each

20 Identify comprehensive set of risks Land Use/ Risk Factor Mission X 1, 2, 3, 4 Y 2, 3, 5 Z 3, 6

21 Identify feasible management alternatives Where and how might the various land uses potentially be distributed across the landscape?

22 Assign impact scores for each risk source to each species Species A B C Risk Factors yes/no? weight?

23 Map risk scores across region for each species/management combination At a particular pixel, to which risks will species A (B, C, etc.) be subject? From table produced in previous step; basically turn the table into a map.

24 Map species actual/potential density Potentially an actual map of population density or density classes, or of habitat suitability classes For our purposes, three classes(from GIS habitat models): non-habitat, potentially occupied, verified occupied

25 Produce combined/weighted map Weight the map of risk impact scores for each species/management alternative by the map of species density values to get overall risk to each species Combine species maps for multispecies situations: minimize the average risk, minimize the maximum risk (minimax)

26 Challenges with this approach: practical issues Combining disparate data from multiple sources Choices of measurement scales for quantities of interest Need for useful management recommendations based on practically no data

27 Challenges with this approach: conceptual issues Spatial scale of data vs. spatial scale of results vs. spatial scale of application Appropriate way to deal with multiple species Incorporating uncertainty

28 Conclusions Tasks for theoretical ecologists 1) Look for potential applications 2) Look for opportunities to develop relevant theory Need for reciprocal interaction -- feedback from conservation practice to ecological theory

Monitoring for Conservation Planning and Management. Environmental Evaluators Forum EPA Headquarters, USA June 14 15, 2007

Monitoring for Conservation Planning and Management Environmental Evaluators Forum EPA Headquarters, USA June 14 15, 2007 Key Types of Decisions Prioritization (where Status to allocate scarce conservation