presented by lorraine mcinnes photo taken by greg wright
TRANSCRIPT
Movement patterns of Western Diamondback Rattlesnakes (Crotalus atrox) at Bosque del Apache National Wildlife Refuge, New Mexico
Presented by Lorraine McInnes
Photo taken by Greg Wright
Research Objectives
1) Describe rattlesnake movement patterns at
Bosque del Apache?
2) Do movement patterns and hibernacula differ
between riparian and upland habitat?
Project Tasks
Spatial Distributions
Data analysis:
Season and Gender variation, response to Temperature and
Moisture fluctuationsHabitat usage
Data Organization
Vicinity Map
Old
Vicinity Map
New
Distribution
Animal MovementsCreate Minimum Convex PolygonsCalculate Movement ParametersConvert Locations To Paths
Success!!
18 snakes-Routes and Home Range outputs
The wonders of Viewing the Full Extent
Data Editing
To get those results:
Many repetitions, changes in excel and arcmap
Learned many lessons on how to organize this kind of data
Currently:
Have an up to date, edited data file
Simplified, step by step repeatable process to get weekly movement results.
Data
Average size, all snakes (n=18): 31 ha, range 2-81 haAverage size, male (n=11): 35.2 ha, range 5-81 haAverage size, females (n=7): 24 ha, range 2-61 ha
SBDAERR
Sandog
Six S
tall
Bridge
Toile
tte
MLo
opOLD
LFRdNew
S
FeeB
ooth
Fire
shop
Hwy1To
ol
RR Tre
stle
Chucky
Hwy1Mar
sh
Spike
Smok
ey
Hwy1SVC
Mar
shLo
opS
Exit
0
10
20
30
40
50
60
70
80
90
Minimum Convex Polygon-Home Range Area
Hect
are
s
Male
Female
Data
Name Average Distance Total Dist (m) RangeNo Move Days Total Days
Bridge 170.5 1534.5 41.2-382.3 15 24Chucky 55.5 4993.7 1.9-343 78 168Exit 97.9 6901.3 2.2-736.7 23 96Feebooth 59.1 5576.1 3.9-317.5 55 151Fireshop 64.2 4363.7 4.4-612.5 41 110Hwy1Marsh 68.0 4965.8 2.4-167.8 94 168Hwy1SVC 72.0 6980.9 1.1-541.9 169 267Hwy1Tool 84.5 8872.6 1.9-338.1 63 170LFRdNewS 67.9 4754.2 4.3-298.4 90 162MarshLoops 125.6 12053.0 1.4-715.6 63 161MLoopOLD 84.7 2712.0 1.4-435.2 42 76RR Trestle 80.1 7292.4 3.5-390.1 78 171Sandog 97.2 1360.2 2.2-476.9 38 54SBDAERR 31.1 1741.1 1.9-290.2 102 158Six Stall 70.0 3150.6 2.4-241.1 59 106Smokey 96.4 6938.5 5.8-780.8 30 103Spike 123.4 8266.5 2.4-414.7 60 128Toilette 76.1 4108.5 .9-537.4 64 120
Visualizing Snake Movement
Annual Cycle
Next step:
Activity Clustering
Statistical Analysis of Movements to describe movement differences by habitat, season, and gender
*Revisit Spatial Statistics and Regression Analysis Virtual Courses
Road Crossing
Hwy 1 and/or RR was crossed 81 times.
Hwy1Tool-crossed road or tracks 22 times.
Next highest number of crossings: 12
Trials and Tribulations
ArcScene-3D animation
Animation in general
Habitat-spatial join…veg type text to numeric value?!
Hawth’s Tools-route issues continue
Continued Work
Refine movement parameters and generate more descriptive statistics
Animate certain routes to better visualize movement, 2D, 3D-Flythrough tour
Generate habitat use spatial join to determine which habitats the snakes were used more than others
Field work: Characterize new dens and determine site preference based on various parameters-slope, aspect, elevation, proximity to roads, water, man-made structures, etc.
Den Site Suitability model
Questions??