Proposed Framework for 

Species / Habitat and Use Site 

Proximity Analysis

Steve Kay, Pyxis Regulatory Consulting, Inc.

April 22, 2014
Interim Approaches Step 1 Methodology

• Documents process at a high level

• Data neutral approach

• Determines the Action Area based on:

– The spatial location of the use site(s)

– The lowest relevant toxicity value for the 

most sensitive species that results in the 

farthest distance from the use site(s)

• Action Area is the sum of both areas
Proposed Implementation Principles

• Live within the overall rules set by EPA and the 

Services

• The proximity analysis should be:

– Automated, efficient and cost effective

– National in scope

– Sub-county in spatial detail

– Data source independent

– Transparent and reproducible

• Ideally an evolving process that becomes more 

effective over time
Conceptual Implementation

Determine

Action Area

(Most Sensitive Species)

Conduct

Proximity

Analysis

1. Spatially represent species / critical 

habitats

2. Identify species / critical habitats that 

overlap with the Action Area

1. Determine off-site portion of Action 

Area for most sensitive species

2. Spatially represent use site(s)
Hypothetical Scenario

• Insecticide used on orchards / vineyards

• Toxicology

– Highly toxic to insects

– Slightly acutely toxic to birds

– Possible sublethal (chronic) effects to mammals

• Action Area Distances

– Insects = 150 meters (approx. 500 feet)

– Birds = 90 meters (approx. 300 feet)

– Mammals = 60 meters (approx. 200 feet)

• Action Area Distance: 150 meters
Use-Sites: Orchards and Vineyards

Source: 2014 GESTF 

Pesticide Use Sites Dataset 
Action Area Distance from Use Sites
Species / Habitat Locations – All Taxa

Source: USFWS ECOS 

Critical Habitat Portal
Spatial Proximity Analysis
Proximity Analysis – Tabular Results
Proximity Analysis – Results by Taxon

0

5

10

15

20

0 1 - 60 61 - 90 91 - 150 >150

Birds

Insects

Mammals

Most sensitive Taxon

Action Area distance

Number of Species Total

Taxon Within Action Area Outside Action Area Species

Insects 16 57% 12 43% 28

Birds 14 78% 4 22% 18

Mammals 17 77% 5 23% 22

TOTAL 47 69% 21 31% 68
Proximity Analysis – Results by Occurrence

0

1000

2000

3000

4000

5000

6000

0 1 - 60 61 - 90 91 - 150 >150

Birds

Insects

Mammals

Most sensitive Taxon

Action Area distance

Number of Critical Habitat/Species Locations Total

Taxon Within Action Area Outside Action Area Occurrences

Insects 64 351 415

Birds 866 4895 5761

Mammals 394 1390 1784

TOTAL 1324 6636 7960

Number of Critical Habitat / Species Locations Total

Taxon Within Action Area Outside Action Area Occurrences

Insects 64 15% 351 85% 415

Birds 866 15% 4895 85% 5761

Mammals 394 22% 1390 78% 1784

TOTALS 1324 17% 6636 83% 7960
Conceptual Per-Taxon Implementation

Action Area

(Per-Taxon / Species)

Proximity

Analysis

1. Spatially represent species / critical 

habitats

2. Identify species / critical habitats that 

fall within the Action Area

1. Determine off-site portion of Action 

Area for each taxon / species

2. Spatially represent use site(s)
Species / Habitat Locations 
Proximity Analysis – Tabular Results
Proximity Analysis – Results by Taxon

0

5

10

15

20

0 1 - 60 61 - 90 91 - 150 >150

Birds

Insects

Mammals

Insect

AA Dist.

Number of Species Total

Taxon Within Action Area Outside Action Area Species

Insects 16 57% 12 43% 28

Birds 14 78% 4 22% 18

Mammals 16 73% 6 27% 22

TOTAL 47 69% 21 31% 68

Bird

AA Dist.

Mammal

AA Dist.
Proximity Analysis – Results by Occurrence

0

1000

2000

3000

4000

5000

6000

0 1 - 60 61 - 90 91 - 150 >150

Birds

Insects

Mammals

Insect

AA Dist.

Bird

AA Dist.

Mammal

AA Dist.

Number of Critical Habitat/Species Locations Total

Taxon Within Action Area Outside Action Area Occurrences

Insects 64 15% 351 85% 415

Birds 550 10% 5211 90% 5761

Mammals 195 11% 1589 89% 1784

TOTALS 809 10% 7151 90% 7960
Proposed Framework - Summary

• Is flexible

– Can use any spatial data

– Allows more detailed or current data to be easily integrated

– National assessment performed at high resolution

• Is efficient and cost effective

– “Expensive” spatial proximity analysis only rerun when 

underlying use site or species data is updated

– Tabular summarization allows rapid assessment of multiple 

Action Area distances or other “what-if” scenarios

• Facilitates per-taxon assessment by making 

multiple Action Area distances easy to analyze

• Facilitates identification of potential interaction 

sites that need further investigation
Q & A

Steve Kay

Pyxis Regulatory Consulting, Inc.

Tel: 253-853-7369

Email: Steve@PyxisRC.com