Vertebrate populations, trophic dynamics and ecosystem function
description
Transcript of Vertebrate populations, trophic dynamics and ecosystem function
Vertebrate populations, trophic dynamics and ecosystem function
Knut Kielland - LTER Symposium 2008
Population status and trends
- integrative ecological functions
Focus:
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
2003 2004 2005 2006 2007
Cap
ture
s/t
rap
nig
ht
Small mammal abundance index from 8 standardized trap lines interior Alaska 2003-2007. Total trap nights = 5,169
Data: Excel data sheets - available
Data from Whitman, ADF&G
Debevec and Flamme 2007
Denali National Park
Data: NPS LTEM program
0
1
2
3
4
5
6
7
8
9
10
Mar
-98
Jul-9
8No
v-98
Mar
-99
Jul-9
9No
v-99
Mar
-00
Jul-0
0No
v-00
Mar
-01
Jul-0
1No
v-01
Mar
-02
Jul-0
2No
v-02
Mar
-03
Jul-0
3No
v-03
Mar
-04
Jul-0
4No
v-04
Mar
-05
Jul-0
5No
v-05
Mar
-06
Jul-0
6No
v-06
Mar
-07
Jul-0
7No
v-07
Trapping Date (Month)
Hare
den
sity (
ind
ha-1
)
Data: LTER archive thru 2006
0
5000
10000
15000
20000
25000
Moo
se p
opul
atio
n (9
5% C
L)Key: Wolf Control Severe Winter Cow Harvest 5-10% Intensive Management Objective
IMO
Moose population in GMU 20A - Tanana Flats (ADF&G)
Data: electronic and hard copy
= 1.07
High Density Low Density
Cur
rent
Ann
ual G
row
th P
rodu
ctio
n (k
g/ha
)
0
200
400
600
800
1000
Remaining Utilized
33%
6%
(Butler and Kielland 2008)
C
P
5X>
20B
25D
20A
20D
21E
20E
19D
19A
0
0.2
0.4
0.6
0.8
0 0.1 0.2 0.3 0.4 0.5
Proportional browse removal (mean plant)
Moo
se tw
inni
ng ra
te
Spearman’s rho = -0.929, 0.005 < P < 0.001
Data from Paragi, ADF&G
“Early Warning”
TWINNING
20A 20A 13A 20D 19D 20C 25D 17AFLATS HILLS
POPULATION (GMU)
Indices of Nutrition Populations ordered by twinning rate
AGE AT FIRST TWINNING
ADULT PREGNANCY
SHORT-YEARLING MASS
2-YR-OLD PREGNANCY3-YR-OLD PREGNANCY
INCREASING NUTRITION
BROWSE REMOVAL
ADF&G data
Moose mobility & snow depth
10
20
30
40
50
60
70
80
90
100
110
120
130
(cm)10
20
30
40
50
60
70
80
90
100
110
120
130
(cm)
UNRESTRICTED
SLIGHTLY RESTRICTED
RESTRICTED
SERIOUS DIFFICULTY MOVING
MOOSE CONFINED
Source: ADF&G
Brisket height
Snow depth
90 -130 cm
40 - 70 cm
40 cm
Data: ADF&G data base under construction
Lynx ecology
1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Year
0
5000
10000
15000
20000
Nu
mb
er o
f ly
nx
Record of lynx export/sealing data for the state of Alaska 1910-2005 (Kielland compilation 2007)
-28 -27 -26 -25 -24 -23 -22
13C (‰)
1
3
5
7
15N
(‰
)
Snowshoe Hares
Microtines
Lynx
Red Squirrels
Grouse
25 Jan – 1 Feb 2008