# Presentation: 125584

## Notice: The views expressed here are those of the individual authors and may not necessarily reflect the views and policies of the United States Environmental Protection Agency (EPA).  Scientists in EPA have prepared the EPA sections, and those sections have been reviewed in accordance with EPA’s peer and administrative review policies and approved for presentation and publication.  The EPA contributed funding to the construction of this website but is not responsible for it's contents. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.

**Notice: The views expressed here are those of the individual authors and may not necessarily reflect the views and policies of the United States Environmental Protection Agency (EPA).  Scientists in EPA have prepared the EPA sections, and those sections have been reviewed in accordance with EPA’s peer and administrative review policies and approved for presentation and publication.  The EPA contributed funding to the construction of this website but is not responsible for it's contents. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.**

## The Effect of Broad-Scale Habitat Condition 

**on the Location and Quality of **
**Migratory Bird Pathways **

**Roger Tankersley, Jr.**
**Tennessee Valley Authority**
**Kenneth H. Orvis**
**University of Tennessee, Knoxville**

## Migration

**--Seasonal movement from one region to another by**
**chance, instinct, or plan**

**Long Distance Migratory Birds**

**--Avian species whose breeding and wintering habitats**
**are separated by more than 20 degrees latitude**

**Neotropical Migratory Birds**

**--Birds that migrate between nearctic breeding **
**grounds and neotropic wintering grounds**

## Slide 4

## Slide 5

## Slide 6

## Base Landcover

**Base Landcover**

**Available Habitats**

## Slide 8

## Habitat Condition Results:  

- Forest fragmentation and density influence habitat selection during
- migration, especially for long-distance forest migrants.
- Long-distance forest migrants appear to select relatively unfragmented,
- dense forest areas with simple patch boundaries and little coniferous
- canopy.  They avoid heavily disturbed areas with high road densities
- and a high percentage of agriculture in the surrounding landscape.
- These species appear to effectively sample widely separated habitats
- en-route, suggesting that inherited genetic cues for migratory pathways
- and habitat selection play an important role in stopover selection.

## --Habitat  

- Spatial Distribution is key
**--Orientation:**
- Stellar compass, magnetic compass, olfactory navigation, infrasound.
- Probably inherited, and likely a constant direction.  Species composed
- of many individuals migrating in slightly different ways.
**--Nightly Flight Distance:**
- Largely determined by morphology--body size, wing shape, musculature.
- Re-fueling determines available energy.

_**Models of Migration Pathways**_

## Local Forest

- Density

- Percent Agriculture

- Road Density

- Integrated Habitat

## Slide 12

## Slide 13

## Broad Front vs. 

**Broad Front vs. **
**Directed Migration**

**--Broad front migration = **
**no significant impact from**
**removing one stopover**
**--Direct migration = **
**possible significant impact to **
**particular breeding populations**

## Habitat

**Habitat**

**Pathways**

**Application to ReVA**

## Other Applications and Future Research:

**--Future scenarios based on landcover change**
**--Climate Change**
**--Environmental assessment tool for Windmills**
**and other vertical obstructions**

## Mahalanobis Distance 

**Mahalanobis Distance **
**Habitat Modeling**

**--More robust models**
**--Based on “Ideal” **
**habitat conditions**
**--Can be used as a probability**
**of survivorship**

## Possible Climate Change Effects

**--Likely to have shifting species distributions**
**--Likely to become asynchronous with leaf-out and insects**
**--Modern habitat landscape makes it difficult for species to**
**adapt quickly enough**

## Slide 19

## Slide 20

## Assessing Environmental 

**Assessing Environmental **
**Impact of Windmills**

**--Windmills abundant in western U.S.**
**--Many projects planned in the east**
**--Bird impacts may be significant**

**Project goals:**
**--Examine overlap between quality**
**wind sites and migratory corridors**
**--Create environmental decision tool**
**that incorporates avian considerations**
**early in the decision process**

## Slide 23

## ACKNOWLEDGEMENTS

**Funded by EPA Regional Vulnerability Assessment **
**program, through an interagency agreement with TVA.**
**Volunteer birders who sampled 128 patches.**
**Statistical help and reading of early manuscripts.**
**Pathways modeling available in *****Conservation Ecology***
**http://www.consecol.org**