Community Ecology

Community Ecology

Introduction

Introduced Predators Transform Subarctic Islands from Grassland to Tundra D. A. Croll,1 J. L. Maron,2 J. A. Estes,1,3 E. M. Danner,1 G. V. Byrd4

+ Foxes - Foxes

Ecological Meltdown in Predator-Free Forest Fragments John Terborgh,1* Lawrence Lopez,2 Percy Nuñez,3 Madhu Rao,4, 5 Ghazala Shahabuddin,6 Gabriela Orihuela,7 Mailen Riveros,8

Rafael Ascanio,9 Greg H. Adler,11 Thomas D. Lambert,10 Luis Balbas12

Pattern

a, Species–area relationship: earthworms in areas ranging from 100 m2 to >500,000 km2 across Europe76. b, Species–latitude relationship: birds in grid cells (  611,000 km2) across the New World44. c, Relationship between local and regional richness: lacustrine fish in North America (orange circles, large lakes; blue circles, small lakes)61. d, Species–elevation relationship: bats in Manu National Park & Biosphere Reserve, Peru77. e, Species–precipitation relationship: woody plants in grid cells (20,000 km2) in southern Africa78.

Nature 405, 220 - 227 (11 May 2000); doi:10.1038/35012228

Global patterns in biodiversity

KEVIN J. GASTON

Process

Hypotheses: Competing or complimentary

?

Out of the Tropics: Evolutionary Dynamics of the Latitudinal Diversity

Gradient David Jablonski,1 Kaustuv Roy,2 James W. Valentine3

Local Diversity

• Local processes build up to region?• Density/frequency dependence, niches

• Regional processes filter to local?• Source pools, extinction speciation, neutral theory, niches

Biodiversity Hotspots

Biodiversity hotspots for conservation prioritiesNorman Myers, Russell A. Mittermeier, Cristina G. Mittermeier, Gustavo A. B. da Fonseca and Jennifer Kent

Nature 403, 853-858 (24 February 2000)

L. M. Curran et al., Science 303, 1000 -1003 (2004)

Fig. 1. Our case study area, GPNP and its surrounding 10-km buffer (black), is located on the southwest coast of the island of Borneo, in the province of West Kalimantan

(light gray)

• Habitat loss• What do we expect to happen to communities?

– What is a community?– What measures are we interested in? How do they

change?– How do we go about getting at cause and effect in

complex systems?

L. M. Curran et al., Science 303, 1000 -1003 (2004)

Fig. 2. Cumulative forest loss within the GPNP boundary (yellow) and its surrounding 10-km buffer. Forest and nonforest classifications (13) are based on a Landsat Thematic Mapper time series). Classifications are shown for (A) 1988, (B) 1994, and (C) 2002.

Harvesting effects

How do we get from great whale harvests (left) to kelp decline?

Harvesting: Fisheries management

Fig. 1. Fraction of the sea bottom and adjacent waters contributing to the world fisheries from 1950 to 2000 (30) and projected to 2050 by depth (logarithmic scale). Note the strong reversal of trends required for 20% of the waters down to 100-m depth to be protected from fishing by 2020.

The Future for Fisheries Daniel Pauly,1 Jackie Alder,1 Elena Bennett,2 Villy Christensen,1 Peter Tyedmers,3 Reg Watson1

48,000 Years of Climate and Forest Change in a Biodiversity Hot Spot Mark B. Bush,1   Miles R. Silman,2*   Dunia H. Urrego

Representation of pollen taxa

Continuous, high resolution (5mm/yr) core

Continuous wet forest taxa for 50,000 yrs

Gradual change in community composition

Consuelo Ordination

Two basic states(1)30 kyr(2)11 kyrEvidence of

cycles

DCA Axis 1

0 50 100 150 200

Age (

cal y

r bp)

0

10000

20000

30000

40000

50000

DCA Axis 1 vs. Time

• Two major forest types

• Periodic changes– ENSO, drought

cycles, D-O events

• Gradual ~8-10 ky transition

• Non-equilibrium?