Finish PVA.Begin Habitat

Fragmentation and LossWed. Mar. 16

PVA Output

Orangutans and PVA --1000 yr MVP

Isle Royale NP Wolves and PVA

Failure

Hindcast PVA "predicted" 1980's management practices and conditions would yield populations greater than the MVP.

• Parvovirus

• Prey decline

Types of PVAs

Count-based PVAno real demographic data – population parameters

are based on whole populations.

Demographic (Stage-Based) PVA

Multi-site PVAs (some types are spatially explicit)

Rules of Use

1. Use the PVA consistent with available high quality data.

2. Understand the workings of canned models

3. Provide confidence intervals

4. Relative gauge –decline? steady? increase?

5. Don't go too far, especially in generational terms.

Critiques of PVAs

Uncertainties in the data – carried forward!

Requirement for very high quality data sets

Emphasis on a single species – this is usually not the real issue in conservation (it can be, however).

Use in determining whether or not a species will drop below its "ecologically functional population size."

Habitat Degradation and Loss

Land Use History in New

England

Results of Land Use in New England

Agroecology 101

Loss of Native Vegetation in the USA

What is the single greatest cause of diversity loss in native plant diversity in the US?Why are some areas less touched?

Forms of Habitat

Degradation

Land Use Intensity and Species Loss in Africa

Why do bird populations seem to do a bit better, relatively speaking.

Documenting Habitat Loss

Note recent trend to loss of wetlands and tropical lands and even some desert.

Conservation Risk Index

(by WWF and TNC)

CRI =

CRI = Converted/Preserved

Critical = CRI>25 + >50% conversionEndangered = CRI>10 + >40%Vulnerable = CRI>2 + >20%

Critical = 64Endangered = 80Vulnerable = 161

At- Risk Plant Diversity Hotspots

Map generated by conservation international

Endangered Ecoregions

Critical = CRI>25 + >50% conversionEndangered = CRI>10 + >40%Vulnerable = CRI>2 + >20%

Critical = 64 (dark grey)Endangered = 80 (medium grey)Vulnerable = 161 (light grey)

Some Examples of Habitat Degradation and Loss

Habitat Conversion:Clear Cutting

"Clear-Cutting"

in Forests

and Oceans

Damage from

Trawlingwww.skytruth.org

Trails tend to persist many hours

http://archives.starbulletin.com/2008/02/25/news/story01.html

http://i.livescience.com/images/080220-trawling-plumes-02.jpg

Trawls

http://app2.iris.usm.maine.edu/gulfofmaine-censusdev/wp-content/images/Technology/STPCOImage04b.jpg

Bar Trawl

http://app2.iris.usm.maine.edu/gulfofmaine-censusdev/wp-content/images/Technology/STPCOImage01b.jpg

Otter Trawl

Habitat Conversion:The South Florida Example

http://fpc.dos.state.fl.us/r

http://farm6.static.flickr.com/

Draining and Managing the "Glades"

http://en.wikipedia.org/wiki/File:USGS_Northern_Everglades_image_2001_.jpg

Effects of Dikes and

Canals

http://thisisbeirut.files.wordpress.com/2010/09/

Natural and Agricultural Zones