The Effects of Military Jet Overflights on
Dall’s Sheep in Interior Alaska
TABLE OF CONTENTS
SUMMARY
ACKNOWLEDGEMENTS
TABLE
OF CONTENTS
LIST
OF FIGURES
LIST
OF TABLES
INTRODUCTION
DALL’S SHEEP
MILITARY OPERATIONS AREAS
IMPACTS
OF OVERFLIGHTS ON WILDLIFE
STUDY
SITE SELECTION
GOALS
AND OBJECTIVES
CHAPTER
1
Trends in Dall’s sheep populations
in military overflight areas mitigated and not mitigated for potential negative
impacts
INTRODUCTION
STUDY
AREA
METHODS
Aerial
Surveys and Study Area
DATA
ANALYSIS
RESULTS
Survey
Effort
Trends
in Dall’s sheep numbers in aerial survey units
Trends
in Dall’s sheep populations before and after mitigation
Trends
in Dall’s sheep populations in the Yukon-Tanana Uplands
Precision
of Dall’s sheep surveys in the Yukon-Tanana Uplands
DISCUSSION
SUMMARY
CHAPTER
2
Dall’s sheep productivity, and survival rates in interior Alaska in mitigated
and non-mitigated military overflight areas
INTRODUCTION
STUDY
AREA
METHODS
DATA
ANALYSIS
RESULTS
DISCUSSION
SUMMARY
CHAPTER
3
Dall’s sheep behavior in relation to military overflights in interior Alaska
in mitigated and non-mitigated military overflight areas
INTRODUCTION
STUDY
AREA
METHODs
Overflight
Activity
Behavior
DATA
ANALYSIS
Overflight
Activity
Behavior
RESULTS
Overflight
Activity
Sound
Behavior
in Relation to Daily Military Overflight Activity
Behavior
in Relation to Military Overflight Events
Behavior
in Relation to Proximity and Peak Sound Level of Military Overflight Events
DISCUSSION
Overflight
actvity
Dall’s
sheep behavior in relation to military jet overflights
SUMMARY
CHAPTER
4
Daily Movements, Home Range
Size and Habitat Use by Dall’s Sheep in Relation to Study Area, Year, Season
and Military Aircraft Sorties
INTRODUCTION
METHODS
RESULTS
Potential
influence of military aircraft sorties on behavior and habitat use
Behavior
and habitat use by study area, year and sequence
DISCUSSION
SUMMARY
GENERAL
CONCLUSIONS and MANAGEMENT IMPLICATIONS
LITERATURE
CITED
APPENDICES
APPENDIX
A -- Summary statistics
for June/July aerial Dall’s sheep surveys in interior Alaska Military Operations
Areas
APPENDIX
B -- Physical measurements
of Dall’s sheep captured in interior Alaska during March of 1999, 2000, 2001
and 2002
APPENDIX
C -- Incidental mammal
and bird species observed (or tracks observed) while watching Dall’s sheep
(Ovis dalli)
APPENDIX
D -- Results from microhistological
and nitrogen analysis of sheep pellets in 2 study areas in the Yukon-Tanana
Uplands, Alaska
APPENDIX
E -- Graphical and statistical
analysis of the proportion of time Dall’s sheep spent active, the feeding
efficiency, and behavior of Dall’s sheep relative to overflights by small
civilian single engine fixed wing aircraft
APPENDIX
F -- Power Analysis for
Usage Variables
LIST OF FIGURES
Figure
1 -- Dall’s sheep distribution
and military special use airspace (MOAs) in Alaska
Figure
2 -- Location of Military
Operations Areas (MOAs) in interior Alaska
Figure
1.1 -- Military Operations
Areas (MOAs) in Interior Alaska. Areas mitigated for protecting Dall’s sheep
are also shown
Figure
1.2 -- Dall’s sheep survey
units in the Yukon-Tanana Uplands, eastern interior Alaska
Figure
1.3 -- Counts of Dall’s
sheep in Interior Alaska Military Operations Areas
Figure
1.4 -- Densities of Dall’s
sheep in Interior Alaska Military Operations Areas
Figure
1.5 -- Numbers of Dall’s
sheep observed in 7 survey units within the Interior Alaska Military Operations
Areas during summer aerial surveys, 1997-2002
Figure
2.1 -- Location of study
sites in interior Alaska
Figure
2.2 -- Age distribution
of Dall’s sheep captured in 1999, 2000, 2001, and 2002 in interior Alaska
Figure
2.3 -- Body weights (mean
+ SE) of Dall’s sheep captured in interior Alaska at a study site mitigated
for military aircraft overflights and at a non-mitigated site
Figure
2.4 -- The logistic relationship
between the probability of pregnancy and body weight (kg) for adult Dall’s
sheep ewes in the Yukon-Tanana uplands, Alaska
Figure
2.5 -- Lambs:100 ewes and
yearlings:100 ewes observed in July in interior Alaska during an aerial survey
Figure
2.6 -- The Kaplan-Meier
survival probability function for Dall’s sheep radiocollared in the Yukon-Tanana
Uplands, interior Alaska
Figure
2.7 -- The Kaplan-Meier
survival probability function for Dall’s sheep radiocollared in the Yukon-Tanana
uplands, interior Alaska at 2 study sites
Figure
2.8 -- The logistic relationship
between the probability of survival and body weight (kg) for adult Dall’s
sheep ewes in the Yukon-Tanana uplands, Alaska
Figure
3.1 -- Location of study
sites in interior Alaska and their relation to Military Operations Areas (MOAs)
Figure
3.2 -- A comparison of
the number of overflight events observed during the course of field studies
in 2000 and 2001
Figure
3.3 -- Mean (+SE) proportion
of sheep active during scan samples
Figure
3.4 -- Mean (+SE) distance
from rock observed in sheep bands at the start of observation periods
Figure
3.5 -- Feeding efficiency
of Dall’s sheep during scan sampling
Figure
3.6 -- Mean (+SE) behavior
of Dall’s sheep from scan samples
Figure
3.7 -- Mean (+SE) proportion
of Dall’s sheep active in: 1) the 10 minutes before a military overflight
event ; 2) during a military overflight event; and 3) 10 minutes after the
overflight event
Figure
3.8 -- Mean (+SE) feeding
efficiency of Dall’s sheep in: 1) the 10 minutes before a military overflight
event ; 2) during a military overflight event; and 3) 10 minutes after the
overflight event
Figure
3.9 -- Mean (+SE) behavior
of Dall’s sheep in: 1) the 10 minutes before a military overflight event ;
2) during a military overflight event; and 3) 10 minutes after the overflight
event
Figure
3.10 -- Mean (+SE) proportion
of Dall’s sheep active during military jet overflights grouped by proximity
Figure
3.11 -- Mean (+SE) proportion
of Dall’s sheep active during military jet overflights grouped by 2 minute
mean Leq (dBA)
Figure
3.12 -- Mean (+SE) feeding
efficiency of Dall’s sheep during military jet overflights grouped by proximity
Figure
3.13 -- Mean (+SE) feeding
efficiency of Dall’s sheep during military jet overflights grouped by 2 minute
mean Leq (dBA)
Figure
3.14 -- Mean (+SE) behavior
of Dall’s sheep during military jet overflights grouped by proximity
Figure
3.15 Mean (+SE) behavior
of Dall’s sheep during military jet overflights grouped by 2 minute mean Leq
(dBA)
Figure
4.1 -- Average number of
military sorties launched per day into MOA 1, 1999-2002, in eight 2-week sequential
periods within years
Figure
4.2 -- Average MCP home
range size of sheep in relation to number of military sorties launched per
day into MOA 1, interior Alaska, late-April through early-August, 1999-2002
Figure
4.3 -- Average 2-week minimum
total distance traveled by sheep in relation to number of military sorties
launched per day into MOA 1, interior Alaska, late-April through early-August,
1999-2002
Figure
4.4 -- Average terrain
ruggedness used by sheep in relation to number of military sorties launched
per day into MOA 1, interior Alaska, late-April through early-August, 1999-2002
Figure
4.5 -- Average MCP home
range size (km2) for Dall’s sheep in the West Point study area,
interior Alaska, late-April through early-August, 1999-2002
Figure
4.6 -- Average MCP home
range size (km2) for Dall’s sheep in the Cirque Lakes study area,
interior Alaska, late-April through early-August, 1999-2002
Figure
4.7 -- Average minimum
total distance (km) traveled in 2-week sequential periods for Dall’s sheep
in the West Point study area, interior Alaska, late-April through early-August,
1999-2002
Figure
4.8 -- Average minimum
total distance (km) traveled in 2-week sequential periods for Dall’s sheep
in the Cirque Lakes study area, interior Alaska, late-April through early-August,
1999-2002
Figure
4.9 -- Average proportional
use of the sparsely vegetated landcover class for Dall’s sheep in the West
Point study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.10 -- Average proportional
use of the sparsely vegetated landcover class for Dall’s sheep in the Cirque
Lakes study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.11 -- Average proportional
use of the timber landcover class for Dall’s sheep in the West Point study
area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.12 -- Average proportional
use of the timber landcover class for Dall’s sheep in the Cirque Lakes study
area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.13 -- Average proportional
use of the grass-shrub-herb landcover class for Dall’s sheep in the West Point
study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.14 -- Average proportional
use of the grass-shrub-herb landcover class for Dall’s sheep in the Cirque
Lakes study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.15 -- Average maximum
relative green plant biomass (NDVI) at sites used by Dall’s sheep in the West
Point study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.16 -- Average maximum
relative green plant biomass (NDVI) at sites used by Dall’s sheep in the Cirque
Lakes study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.17 -- Average elevation
use for Dall’s sheep in the West Point study area, interior Alaska, late-April
through early-August, 1999-2002
Figure
4.18 -- Average elevation
use for Dall’s sheep in the Cirque Lakes study area, interior Alaska, late-April
through early-August, 1999-2002
Figure
4.19 -- Average slope (%)
use for Dall’s sheep in the West Point study area, interior Alaska, late-April
through early-August, 1999-2002
Figure
4.20 -- Average slope (%)
use for Dall’s sheep in the Cirque Lakes study area, interior Alaska, late-April
through early-August, 1999-2002
Figure
4.21 -- Average terrain
ruggedness use for Dall’s sheep in the West Point study area, interior Alaska,
late-April through early-August, 1999-2002
Figure
4.22 -- Average terrain
ruggedness use for Dall’s sheep in the Cirque Lakes study area, interior Alaska,
late-April through early-August, 1999-2002
Figure
4.23 -- Average proportional
use of southern aspects (136-225o) for Dall’s sheep in the West
Point study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.24 -- Average proportional
use of western aspects (226-315o) for Dall’s sheep in the West
Point study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.25 -- Average proportional
use of northern aspects (316-045o) for Dall’s sheep in the West
Point study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.26 -- Average proportional
use of eastern aspects (046-135o) for Dall’s sheep in the West
Point study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.27 -- Average proportional
use of southern aspects (136-225o) for Dall’s sheep in the Cirque
Lakes study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.28 -- Average proportional
use of western aspects (226-315o) for Dall’s sheep in the Cirque
Lakes study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.29 -- Average proportional
use of northern aspects (316-045o) for Dall’s sheep in the Cirque
Lakes study area, interior Alaska, late-April through early-August, 1999-2002
Figure
4.30 -- Average proportional
use of eastern aspects (46-135o) for Dall’s sheep in the Cirque
Lakes study area, interior Alaska, late-April through early-August, 1999-2002
Figure
E.1 -- Mean (+SE) proportion
of Dall’s sheep active during scan sampling in: 1) the 10 minutes before a
small single engine aircraft overflight event; 2) during a small single engine
aircraft overflight event ; and 3) 10 minutes after the overflight event
Figure
E.2 -- Mean (+SE) feeding
efficiency of Dall’s sheep during scan sampling in: 1) the 10 minutes before
a small single engine aircraft overflight event ; 2) during a small single
engine aircraft overflight event; and 3) 10 minutes after the overflight event
Figure
E.3 -- Mean (+SE) behavior
of Dall’s sheep during scan sampling in: 1) the 10 minutes before a small
single engine aircraft overflight event; 2) during a small single engine aircraft
overflight event; and 3) 10 minutes after the overflight evenT
Figure
E.4 -- Mean (+SE) proportion
of Dall’s sheep active during scan sampling during overflights by small civilian
single engine aircraft grouped by proximity
Figure
E.5 -- Mean (+SE) proportion
of Dall’s sheep active during scan sampling during overflights by small civilian
single engine aircraft grouped by 2 minute mean Leq (Dba)
Figure
E.6 -- Mean (+SE) feeding
efficiency of Dall’s sheep during scan sampling during overflights by small
civilian single engine aircraft grouped by proximity
Figure
E.7 -- Mean (+SE) feeding
efficiency of Dall’s sheep during scan sampling during overflights by small
civilian single engine aircraft grouped by 2 minute mean Leq (dBA)
Figure
E.8 -- Mean (+SE) behavior
of Dall’s sheep during scan sampling during overflights by small civilian
single engine aircraft grouped by proximity
Figure
E.9 -- Mean (+SE) behavior
of Dall’s sheep during scan sampling during overflights by small civilian
single engine aircraft grouped by 2 minute mean Leq (dBA)
Figure
F.1 -- Power curves for
detecting sortie effects. Average daily distance traveled and home range
size power curves were calculated
LIST OF TABLES
Table 1.1.
-- Summary statistics for survey effort of summer aerial Dall’s sheep
surveys in interior Alaska, Military Operations Areas from 1997 – 2002
Table
1.2 -- MANOVA results investigating
survey effort and its effect on Dall’s sheep counts in interior Alaska, Military
Operations Areas
Table
1.3 -- Sightability of
Dall’s sheep in Yukon Charley Rivers National Preserve, Alaska 1997 – 2002
Table
2.1 -- Dall’s sheep pregnancy
in interior Alaska at a study site mitigated for the impacts of military aircraft
overflights and at a non-mitigated site
Table
2.2 -- Cause of death
for Dall’s sheep captured in the Yukon-Tanana Uplands of interior Alaska at
a study site mitigated for military aircraft overflights and at a non-mitigated
site
Table
2.3 -- Summary of measures
of productivity of Dall’s sheep in the Yukon-Tanana Uplands of interior Alaska
Table
3.1 -- Dates of Cope Thunder
exercises in interior Alaska Military Overflight Areas and dates crews were
in the field observing Dall’s sheep and military overflights, during 2000
and 2001
Table
3.2 -- Number of overflight
events by aircraft type and proximity to Dall’s sheep observed while watching
Dall’s sheep behavior in interior Alaska during 2000 and 2001
Table
3.3 -- The amount of time
spent observing Dall’s sheep, the number of overflights, and the amount of
time gathering sound level data during 2000 and 2001 at 2 study sites in the
Yukon-Tanana Uplands of Interior Alaska
Table
3.4 -- Minimum and maximum
sound levels measured during overflight events in interior Alaska during 2000
and 2001
Table
3.5 -- Number of occurrences
of sound levels measured during overflight events while observing sheep in
interior Alaska MOAS in 2000 and 2001
Table
3.6 -- Summary of ANCOVA
results examining factors affecting the proportion of time Dall’s sheep were
active
Table
3.7 -- Summary of ANCOVA
results examining factors affecting the feeding efficiency of Dall’s sheep
Table
3.8 -- Summary of MANCOVA
results examining factors affecting the behavior of Dall’s sheep (percent
bedding, standing, feeding, walking, and running)
Table
3.9 -- Summary of ANCOVA
results examining factors affecting the proportion of time Dall’s sheep were
active including the affect of military overflight events
Table
3.10 -- Summary of ANCOVA
results examining factors affecting the feeding efficiency of Dall’s sheep
including the affect of military overflight events
Table
3.11 -- Summary of MANCOVA
results examining factors affecting the behavior of Dall’s sheep (percent
bedding, standing, feeding, walking, and running) including the affect of
military overflight events
Table
3.12 -- Summary of ANCOVA
results examining factors affecting the proportion of time Dall’s sheep were
active including proximity and sound level (2 min. mean Leq [dBA])
of military overflights
Table
3.13 -- Summary of ANCOVA
results examining factors affecting the feeding efficiency of Dall’s sheep
including proximity and sound level (2 min. mean Leq [dBA]) of
military overflights
Table
3.14 -- Summary of MANCOVA
results examining factors affecting the behavior of Dall’s sheep (percent
bedded, standing, feeding, walking, and running) including proximity and sound
level (2 min. mean Leq [dBA]) of military overflights
Table
3.15 -- Summary of significant
statistical results from examining factors that may have affected behavior
of Dall’s sheep
Table
A.1 -- Summary statistics
for June/July aerial Dall’s sheep surveys in interior Alaska Military Operations
Areas
Table
B.1 -- Physical measurements
of Dall’s sheep captured for radiocollaring in interior Alaska during March
of 1999, 2000, 2001 and 2002
Table
C.1 -- Incidental mammal
and bird species observed (or tracks observed) while watching Dall’s sheep
Table
D.1 -- Percent occurrence
of plant species and parts in fecal pellets from Dall's sheep in the Yukon-Tanana
Uplands, Alaska, 2000
Table
D.2 -- Percent occurrence
of plant species and parts in fecal pellets from Dall's sheep in the Yukon-Tanana
Uplands, Alaska, 2001
Table
D.3 -- Percent occurrence
of plant species and parts in fecal pellets from Dall's sheep in the Yukon-Tanana
Uplands, Alaska, 2002
Table
D.4 -- Summary of percent
occurrence by forage group in fecal pellets from Dall's sheep, by study area,
month and year in the Yukon-Tanana Uplands, Alaska
Table
D.5 -- Percent nitrogen
in fecal pellets of Dall's sheep by study area, year and month in the Yukon-Tanana
Uplands, Alaska
Table
E.1 -- Summary of ANCOVA
results examining factors affecting the proportion of time Dall’s sheep were
active including the relation to overflights by small civilian single engine
aircraft
Table
E.2 -- Summary of ANCOVA
results examining factors affecting the feeding efficiency of Dall’s sheep
including the relation to overflights by small civilian single engine aircraft
Table
E.3 -- Summary of MANCOVA
results examining factors affecting the behavior of Dall’s sheep (percent
bedding, standing, feeding, walking, and running) including the relation to
overflights by small civilian single engine aircraft
Table
E.4 -- Summary of ANCOVA
results examining factors affecting the proportion of time Dall’s sheep were
active including proximity and sound level (2 min. mean Leq [dBA])
of overflights by small civilian single engine aircraft
Table
E.5 -- Summary of ANCOVA
results examining factors affecting the feeding efficiency of Dall’s sheep
including proximity and sound level (2 min. mean Leq [dBA]) of
overflights by small civilian single engine aircraft
Table
E.6 -- Summary of MANCOVA
results examining factors affecting the behavior of Dall’s sheep (percent
bedding, standing, feeding, walking, and running) including proximity and
sound level (2 min. mean Leq [dBA]) of overflights by small civilian
single engine aircraft
Chapter
1
2004 Sheep Report
http://www.nps.gov/yuch/Expanded/key_resources/sheep/sheep_2004.htm
Doug Beckstead
December 8, 2004