Mapping Nutritional Resources Across Landscapes:
Why, How, Results
John and Rachel Cook
Photo: Scott
McCorquodale
Elk Herds Declined (1990s)
_
Herd
_Blue Mountains (WA)
Olympics (WA)
Nooksack (WA)
North Rainier (WA)
South Rainier (WA)
Blue Mountains (OR)
Clearwater Basin (ID)
Change
30% Decline
30% Decline
80% Decline
50-70% Decline
30-50% Decline
25% Decline
25% Decline
Cow Summer Body Fat Dynamics
18
2.9 Kcal DE /g
(64% DDM)
Percent Body Fat
16
14
Began Nutrition Treatments
Began nutrition
treatments
12
2.65 Kcal DE/g
(58% DDM)
10
8
6
2.40 Kcal DE/g
(53% DDM)
High Medium Low
4
2
March
June
October
Cumulative Breeding (%)
Autumn Breeding Dynamics
100
High Nutr.
80
60
Medium Nutr.
40
20
Low Nutr.
0
20 Sep
4 Oct
18 Oct
1 Nov
27 Sep
11 Oct
25 Oct
8 Nov
Breeding Date (Julian day)
300
Probability of Breeding
1.0
0.8
0.6 1997
0.4
1996
0.2
0.0
0
5
10
15
20
Total Body Fat (%)
25
y = 266.7 x 1.5543
(1/x)
290
280
270
260
5
10
15
20
Total Body Fat (%)
25
Calf Growth and Winter Survival
1997
100
80
High Nutr.
Body Mass (kg)
120
100
Medium Nutr.
80
Low Nutr.
60
40
20
27 Aug
26 Oct
60
40
20
y = -109.9 + 3.1656x - 0.0120088x
2
2
r = 0.63; P < 0.001
0
60
80
100
120
140
120
140
1998
100
80
y = 4.1 + 0.479x
r 2 = 0.38; P < 0.001
60
40
20
Weaned
1 Jul
Days of Winter Survived (no.)
140
26 Dec
0
60
80
100
Beginning Body Mass (kg)
Documenting Patterns of Nutritional
Limitations in Wild Herds
22 elk herds in 5 states
12 years (1998 to 2010)
Twice/year captures
~ 3,000 elk sampled
Wild Elk Capture
Nooksack
Forks
Chehalis Val.
Wynoochee
Green River
White
River
Pe Ell
Data Collected:
Colockum
Ø Body fat
Ø Age
Ø Pregnancy status
Ø Lactation status
Ø Weight
Ø Blood, fecal samples
Yakima
South
Rainier
Hanford
Mount St. Helens
Wenaha
Sled
Springs
Springfield
Roseburg
Yellowstone
Cody, Wyoming
Black Hills,
South Dakota
Rocky Mtn Nat’l
Park, Colorado
Rocky Mtn
National Park
San Luis Valley, Colorado
Autumn Body Fat of Lactating Wild Elk Cows
Autumn body fat (%)
15
Coastal
Plains and
Foothills
Cascade
Foothills and
Mountains
Inland
Northwest
Central
Rocky
Mountains
Adequate
nutrition
Adequate
nutrition
Adequate
nutrition
Adequate
nutrition
Highly deficient
nutrition
Highly deficient
nutrition
10
5
Highly deficient
nutrition
Highly deficient
nutrition
0
Rectangle denotes 1 herd;
Each dot represents 1 year of data;
Vertical lines are + 1 S.E.
Pregnancy Rates of Lactating Cow Elk
95%(3)
64%(2)
53%(2)
74%(2)
Black Hills, SD:
82% (all,1)
66%(all,4)
78%(7)
80%(2)
Rocky Mtn. NP,
CO: 78% (1)
San Luis Val.,
CO: 88% (2)
86%(3)
86%(2)
79%(4)
50%
(all,2)
80%(2)
89%(2)
71%(2)
90%(6)
88%(2)
Reject
the hypothesis that nutritional influences
are of little or no practical relevance
and
the hypothesis that summer nutrition is
ubiquitously satisfactory and thus is of
little or no practical relevance
Instead,
The relevant
questions are how
severe, where,
why, and what can
be done about it?
General DDE – Animal Performance Relationships
Percent of maximum
120
Poor
Poor
Marginal
Marginal
Good
Good
Excellent
Excellent
<2.4 (53% DDM)
2.4-2.7
2.7-2.9
>2.9 (64% DDM)
100
80
60
40
20
0
Digestible energy of diets (kcal/gram of food)
Calf growth
Yearling growth
Yearling preg
Adult fat
Adult preg
Breeding times
Winter survival
Digestible Energy Content of Consumed Forage:
Our Nutrition Variable for Resource Mapping
 DE plays a key, usually dominant role in virtually all life processes
and it greatly affects how much food ruminants can eat each day…the
“multiplier effect”.
There is considerable precedence…National Research Council
presents livestock nutritional requirements guidelines several ways,
including DE content of food.
Integrating Plant Succession, Disturbance,
and Elk Nutrition
Habitat predictor variables
Stand/site
characteristics
Stand age
Animal response variables
Understory
vegetation
characteristics
Canopy cover
Animal foraging
outcomes
Bite mass
Composition
Bite rate
BA, QMD, TPH, HT
Repro, Surv
Biomass
Season
DDP, DDE
DP, DE
Climate
Foraging time
Palatability
Soils
Performance
outcomes
Integrating Plant Succession, Disturbance,
and Elk Nutrition
Macroplots:
n = 349 total
n = 89 w/elk
Nooksack S.A.
Willipa Hills S.A.
Springfield S.A.
Examples of Accepted/Avoided Forage
Accepted Forage
Selected Forage
Neutral Forage
Avoided Forage
Deciduous shrubs:
Big leaf maple
Hazelnut
Cascara
Forbs:
Queen’s cup beadlily
Northern bedstraw
False Solomon’s seal
Oxalis
Most grasses
Deciduous shrubs:
Alder
Elderberry
Salmonberry
Many forbs
Ferns:
Lady fern
Evergreen shrubs:
Salal
Oregon grape
Rhododendron
Ferns:
Deerfern
Swordfern
Most conifers
Digestible Energy of Elk Diets
3.4
Digestible energy (kcal/g)
r2 = 0.50-0.55;
3.2
P < 0.001
3.0
2.8
2.6
Maintenance =
2.7 kcal/g
2.4
2.2
MHZ & PSFZ WHZ
2.0
1.8
0
300
600
900
1200
Neutral + selected biomass (kg/ha)
1500
Equations to Predict Dietary Digestible Energy
(DDE)
n
r2adj
P
MHZ & PSZ Habitats, All Study Areas
DDE = a + b1(NeuB) + b2(SelB) – b3(NeuB*SelB)
14
0.43
0.036
WHZ Habitats, Nooksack
DDE = a + b1(NeuB) + b2(SelB) – b3(NeuB*SelB)
19
0.39
0.015
WHZ Habitats, Willipa Hills
DDE = a + b1(NeuB) + b2(SelB) – b3(NeuB*SelB)
26
0.46
0.001
WHZ Habitats, Springfield
DDE = a + b1(NeuB) + b2(SelB) – b3(NeuB*SelB)
28
0.57
0.0001
Equationsa,b
a
NeuB = Neutral spp biomass; SelB = Selected spp biomass
b P < 0.075 individually for each predictor variable.
3.2
Observed DDE (kcal/g)
Dietary DE (kcal/g)
Prediction Accuracy of DDE Equations
Observed Predicted
3.0
2.8
2.6
2.4
2.2
0
25
50
Stand age (years)
75
3.4
r 2 = 0.62
3.2
b = 0.98
3.0
2.8
2.6
2.4
2.2
2.2 2.4 2.6 2.8 3.0 3.2
Predicted DDE (kcal/g)
3.2
All study
3.0
areas
2.8
Observed
Nooksack
Predicted
Willipa Hills
2.6
Springfield
All study
areas
2.4
2.2
10
10
16
12
16
12
15
Thi
nne
d
Unt
hin
ned
10
LwCCF
LwESS
13
LwCCF
LwESS
2
LwCCF
LwESS
2.0
Hi-C
CF
Hi-E
SS
Dietary DE (kcal/g)
Prediction Accuracy of DDE Equations
CCF = Closed canopy forest (>65% CC); ESS = Early Seral Stage (<65% CC
Hi = High elevation MHZ & PSZ habitats; Lw = Low elevation WHZ habitats)
Overstory canopy cover (%)
Overstory canopy cover (%)
Overstory Canopy Cover Development
100
80
60
Western hemlock zone
40
20
0
0
100
200
300
400
500
600
700
100
80
Pacific fir zone
60
40
Mountain hemlock zone
20
0
0
100
200
300
Stand age (years)
400
500
Understory Production (kg/ha)
Understory Production (kg/ha)
3,500
Springfield, OR
3,000
Conifer
E. Shrub
For. Ferns
PTAQ
Sedge
Grass
Forb
D.Shrub
2,500
2,000
1,500
1,000
500
0
1
6
9
3,500
14 18 21 24 30 34 37 40 44 55 58 63 73 92 153 307 479 642
Springfield, OR
3,000
Age > 50 years,
Mean “accepted” biomass = 50 kg/ha
2,500
2,000
Avoided
Neutral
Selected
1,500
1,000
500
0
1
6
9
14 18 21 24 30 34 37 40 44 55 58 63 73 92 153 307 479 642
Stand Age (years)
Digestible Energy of Elk Diets
Digestible energy (kcal/g)
3.4
Age > 50 years,
Mean “accepted” biomass = 50 kg/ha
3.2
3.0
2.8
Maintenance
2.6
2.4
2.2
MHZ & PSFZ WHZ
2.0
1.8
0
300
600
900
1200
Neutral + selected biomass (kg/ha)
1500
Equations to Predict Forage Biomass Groups
Equationsa,b
n
r2adj
P
MHZ & PSZ Habitats, All Study Areas
AccB = a - b1(CC) + b2(CC2) + b3(HWd)
70
0.70
<0.001
NeuB = a - b1(CC) + b3(HWd)
70
0.72
<0.001
SelB = 1/(a + b1*CC)
70
0.30
<0.001
a AccB = accepted spp biomass; NeuB = neutral spp biomass; SelB =
selected spp biomass; CC = canopy cover; HWd = hardwood stems.
b P < 0.05 individually for each predictor variable.
Equations to Predict Forage Biomass Groups
n
r2adj
AccB = a - b1(CC) + b2(CC2) + b3(HWd)
276
0.68
<0.001
NeuB = a - b1(CC) + b2(CC2) + b3(HWd)
276
0.65
<0.001
SelB = a - b1(CC) + b3(HWd)
276
0.46
<0.001
Equationsa,b
P
WHZ Habitats, By Study Area
a AccB = accepted spp biomass; NeuB = neutral spp biomass; SelB =
selected spp biomass; CC = canopy cover; HWd = hardwood stems.
b P < 0.05 individually for each predictor variable.
Western Hemlock Habitats
Accepted biomass (kg/ha)
2,500
Nooksack Willipa Hills Springfield
2,000
1,500
Hardwood-riparian
stands
1,000
500
0
0
20
40
60
80
Overstory canopy cover (%)
100
Prediction Accuracy of Forage Equations
1,800
Observed Predicted
600
400
200
0
1
5
9
200
100
1
5
9
13 17 21 25 29 33 37 41 45 49 53 57 63 69 73 82 107 146 192 307 494
Stand age (years)
900
600
300
0
13 17 21 25 29 33 37 41 45 49 53 57 63 69 73 82 107 146 192 307 494
300
r 2 = 0.68
b = 1.00
1,200
600
Observed (kg/ha)
Selected spp (kg/ha)
1,500
Stand age (years)
400
0
Observed (kg/ha)
Neutral spp (kg/ha)
800
500
0
200 400 600 800 1,000
Predicted
(kg/ha)
2
r = 0.45
b = 1.00
400
300
200
100
0
0
50
100
150
200
250
Predicted (kg/ha)
Prediction Accuracy of Forage Equations
Observed
Predicted-1
Predicted-2
3.0 All study
areas
2.8
Nooksack
Willipa Hills
2.6
Springfield
All study
areas
Thinn
ed
Unth
inned
Lw-E
SS
Lw-C
CF
Lw-E
SS
Lw-C
CF
Lw-E
SS
Lw-C
CF
2.2
Hi-ES
S
2.4
Hi-CC
F
Dietary DE (kcal/g)
3.2
CCF = Closed canopy forest (>65% CC); ESS = Early Seral Stage (<65% CC)
Hi = High elevation MHZ & PSZ habitats; Lw = Low elevation WHZ habitats)
Nutrition Succession Trajectories
Western Hemlock-Salal Habitats
Dietary DE (kcal/g)
3.4
Nooksack
3.2
3.0
Willipa Hills
2.8
Springfield
Maintenance
2.6
2.4
2.2
0
50
100 150 200 250 300 350 400 450 500 550 600 650
Stand Age (years)
Nutrition Succession Trajectories
Western Hemlock-swordfern Habitats
Dietary DE (kcal/g)
3.6
Nooksack
3.4
3.2
Hardwood-riparian
3.0
2.8
Maintenance
Springfield
Willipa Hills
2.6
2.4
2.2
0
50
100
150
200
250
300
350
Stand Age (years)
400
450
500
550
600
Nutrition Succession Trajectories
Mountain Hemlock & Pacific Fir Habitats
Dietary DE (kcal/g)
3.4
Nooksack
3.2
3.0
2.8
Willipa Hills
Maintenance
Springfield
2.6
2.4
0
50
100
150
200
250
300
Stand Age (years)
350
400
450
500
Pacific Fir & Mtn
Hemlock Zones
Percent of Area
80
60
40
20
Percent of Area
0
Percent of Area
Poor
80
Marginal
Good Excellent
Oregon Cascades
60
40
20
0
80
Poor
Marginal
Good Excellent
Washington Coast Range
60
40
20
0
Percent of Area
Washington Cascades
Poor
80
Marginal
Good Excellent
Oregon Coast Range
60
40
20
0
Poor
Marginal
Good Excellent
Location: Preg%; BF%
Nooksack: 95%; 13%
Forks: 64%; 6%
Wynoochee: 53%; 6%
Green River: 78%; 10%
White River: 86%; 11%
Willipa Hills: 74%; 6%
Mount St. Helens: 70%; ?%
Springfield: 80%; 10%
Suislaw: 50%; ~5%
Steamboat: 88%; 7%
Toketee: 69%; 9%