Announcements

• Reading Assignments– BSCI363: Chapters 4 and 5– CONS670: Chapters 8 and 15

Tragedy of the Commons

The Value of Ecosystem ServicesEcosystem Service Value ( Billions)

Gas Regulation 1,341

Climate Regulation 684

Disturbance Regulation 1,779

Water Regulation 1,115

Water Supply 1,692

Erosion Control 576

Soil Formation 53

Nutrient Cycling 17,075

Waste Treatment 2,277

Pollination 117

Biological Control 417

Refugia 124

Food 1,386

Raw Materials 721

Genetic Resources 79

Recreation 815

Cultural 3,015

TOTAL 33,268

Costanza, R et al. 1997. The value of the world's ecosystem services and natural capital. Nature 387:253-260.

Deforestation of the Seafloor

• The area of seabed trawled worldwide is ~ 150 times greater than the area of forest clearcut each year (an area twice the size of the lower 48 United States).• Although some spots escape trawling by chance or because they don't have fish, each square foot of the world's continental shelves is trawled every ~ 2 years

http://www.mcbi.org/btrawl/wnpaper.htmlWatling et al. 1998. Disturbance of the seabed by mobile fishing gear: a comparison with forest clearcutting. Cons. Biol. 12. 1180-1197.

Marine Reserves

• Based on a review of more than 100 marine reserves– population densities were on average 91% higher

– biomass was 192% higher

– average organism size was 31% higher

– species diversity was 23% higher

• Responses tended to be rapid (1-2 years after protection) and persistent (> 40 years).

The Scientific Theory of Marine Reserves. AAAS Session: Science and the Biosphere, 2001.

Marine Reserves

• Reserves may contribute to recruitment both inside and outside of reserve boundaries

• Fisheries interests should benefit from this spillover, recruitment enhancement, and sustainable harvest.

The Scientific Theory of Marine Reserves. AAAS Session: Science and the Biosphere, 2001.

Outline

• Ecosystem Ecology– Biodiversity and ecosystem services– Ecosystem services– The economic value of ecosystem services

• Biodiversity Management– Equilibrium Theory of Island Biogeography– Modern Approaches

Habitat Fragmentation

Species Area Curves

S = CAZ (log S) = Z (log A) + (log C)

From: Gotelli, N. J. 1995. A primer of ecology. Sunderland, MA: Sinauer Assoc. 1-206 p.

Equilibrium Theory of Biogeography

Species richness on islands or habitat patches is a balance between colonization and extinction

Colonization Dynamics

# Island Species

Col

oniz

atio

n

Island spp., “S” P

Mainland pool ofspp., “P”

C declines to 0 where # island species = P (no more colonists available)

Extinction Dynamics

# Island Species

Ext

inct

ion

Island spp., “S” P

Mainland pool ofspp., “P”

E is proportional to the total number of species. E reaches its maximum value at P

Turnover Dynamics and Island Spp. Richness

Extinction

Colonization

# Island Species

Tur

nove

r (i

.e.,

E o

r C

)

P

S

T

T = point where extinction rate = colonization rate.T determines the species richness for an island (S).

Nonlinear E and C

C

E

# Island Species

Tur

nove

r (i

.e.,

E o

r C

)

P

S

T

E

C

# Island Species

Tur

nove

r (i

.e.,

E o

r C

)P

ST

Pattern and conclusions are identical for linear and nonlinear E and C

Review: Metapopulation Models

• E decreases as patch size (area) increases.

• C increases as distance between patches decreases.

ES

Colonization

Tur

nove

r (i

.e.,

E o

r C

)

P

EL

SS SL

# Island Species

Area Effect

SS SL

P

Distance Effect

ExtinctionCN

# Island Species

Tur

nove

r (i

.e.,

E o

r C

)

P

SNSF

CFSN

P

SF

Number of Species on an Island

CN

Tur

nove

r (i

.e.,

E o

r C

)

P

SNS

SFL

SFS

CF

ES

EL

SNL

# Island Species

SNL

P

SFN

SNS

SFS

Application of Island Biogeography

The good, the bad, and the ugly . . .

Distance and Species Richness

From: Gotelli, N. J. 1995. A primer of ecology. Sunderland, MA: Sinauer Assoc. 1-206 p.

Contributions of ETIB

• Metaphor of refuge as an island or spaceship

• Interest in the fragility of the biota of individual refuges and causes of this fragility

• Rules of refuge design?

Hanski, I. A., and G. M.E., editors. 1996. Metapopulation biology: ecology, genetics, and evolution. San Diego, CA: Academic Press. 512 p.

“Island Biogeographic” Reserve Rules: IUCN, WWF

?

?

Good: Make reserve as large as possibleBad: Scaling is species / process specificUgly: Abandon small reserves

Good: True for spp. w/ large range req.Bad: False for spp. w/ small range req.Ugly: Not based on ETIB

Good: True for “interior” spp.Bad: False for “edge” spp.Ugly: Not based on ETIB

Good: Potentially increase connectivityBad: Effectiveness remains unclearUgly: Increase synchrony of populations

?

Fundamental Problems w/ ETIB?

Area (Samples)

Spec

ies

• Alternative explanations for species-area relationship– Sampling

– Habitat diversity

• How do we define TURNOVER?

ETIB and Forest Reserves

Pimm, S. L. 1998. Ecology: The forest fragment classic. Nature 393:23-24.

ETIB and Forest Reserves

• Spp. lost in small fragments– Top predators– Primates– Army ants and company

• What about frogs?– Limited by breeding sites– Peccaries

Reserve Rules vs. Reality

• Reserve design will be species specific.

• Reserve design will be site specific.

• The idea of “optimal” reserve design may miss the point entirely.– We are rarely faced with these alternatives.

• ETIB is considered by many to be a “false start” in Conservation Biology

Application of ETIB

• Application of ETIB to reserve design has been widely criticized

• “Faunal collapse” refers to the loss of species following insularization.– Broadly accepted– Basis for many estimates of extinction rates– Caveats

• Considerable error when used for prediction

Extinctions of large mammals in parks and reserves

Park Name Area (km2) Age (yrs) # spp.lost

% spp.lost

Bryce Canyon 144 61 5 36

Lassen Volcanic 426 77 6 43

Mt. Ranier 976 85 7 32

Rocky Mtn. 1049 69 2 31

Yosemite 20083 94 4 25

Grand Teton-Yellowstone

10328 83.5 1 4

Kootenay-Banff-Jasper 20736 84.5 0 0

Newmark, W. D. 1995. Extinction of mammal populations in western North American national parks. Conservation Biology 5: 67-78.

Application of ETIB

McDonald, K. A., and J. H. Brown. 1992. Using montane mammals to model extinctions due to global change. Conservation Biology 6: 409-415.

Application of ETIB

McDonald, K. A., and J. H. Brown. 1992. Using montane mammals to model extinctions due to global change. Conservation Biology 6: 409-415.

Application of ETIB

McDonald, K. A., and J. H. Brown. 1992. Using montane mammals to model extinctions due to global change. Conservation Biology 6: 409-415.

Community Ecology and Conservation: Nested Communities

4 8 5 1 15 19 16 13 3 18 12 9 11 7 6 14 10 2 17

Eu x x x x x x x x x x x x x x x x x

Ed x x x x x x x x x x x x x x x x x

Ml x x x x x x x x x x x x x

Mf x x x x x x x x x x x

Sp x x x x x x x

Op x x x x x

Sb x x