Deer and Plants on the George Reserve, Michigan:

Deer and Plants on the George
Reserve, Michigan:
This is work that was done in the 1960s
and 1970s, so the “It’s Complicated”
includes where it came in my life and
career as well.
Sex and Age, Density, Social Order,
Forage Class, Digestibility, Acorns,
Snow…It’s Complicated
Dale R. McCullough, Prof. Emeritus, ESPM
and MVZ, University of California, Berkeley
Aldo
Leopold
1957, South Dakota State
College
1887-1948
“Father of
Wildlife
Management”
BS in Wildlife Management
Then I had an “Aha Moment!”
A herd of sheep.
The Science Boundary, and its
importance.
Facts: Data based knowledge
____________________________
It is at this boundary where testable
hypotheses can be framed.
Observational studies = correlation.
Hypothesis test = cause and effect.
Inference, paradigm, myth and
religion
1959 Oregon State MS, Wildlife Manage.
Chuck Warren, Population and
ecosystem modeling.
Jerome C. R. Li, Statistical analysis and
experimental design.
H. J. Andrews Experimental Forest
• As a young graduate student
in 1959 I thought:
• “What we really need in
wildlife research is controlled
experiments.”
Alternatives for a natural scientist:
1. Take advantage of natural
experiments.
2. Manipulate one variable in cases
where other variable remain
nearly constant.
1960-66. University of California,
Berkeley
Ph.D. with A. Starker Leopold
In the Museum of Vertebrate Zoology
Tule elk in Owns Valley, CA
1966 Assistant Professor, University
of Michigan, College of Natural
Resources.
The E. S. George Reserve,
near Pinckney, MI.
1966
Deer-proof fenced, 464 hectors (1,146 acres).
Buck
private
White
T. Deer
Col. Edwin S. George, Detroit Industrialist
In 1920s, bought 12 adjacent farms, and fenced
them. Used area for recreation. Flew from Detroit.
1928, introduced 6 deer, 2 males, 4 females.
Colonel
Edwin S.
George
1930, gave to U. Michigan as a natural area for
research. He reserved 40a and house for his use.
1940, George died and his heirs relinquished all
rights to the University of Michigan.
Private deer herd owned by the
University of Michigan, can be managed
without State of Michigan approval.
Herd can be manipulated to test
population responses, collect samples,
measure biological parameters, etc.
Relatively stable environment year-toyear in southern Michigan.
Pre-existing data and materials I came
into possession of:
Annual deer drive population estimates
from 1933 up to the present (33 years).
All jawbones of deer harvested or
found dead were saved since 1952 (14
years).
My research on deer and plants on
the George Reserve:
1966-1987, 21 years,
Supported by a series of grants from
NSF.
1979
First, the deer:
Population dynamics. How does it all
work???
The first thing we need to know is,
duh, how many are there?
Simple question….
Annual deer drive estimates.
Difficult answer.
Reconstructed population estimates.
The deer do not cooperate.
Annual deer drives, 1933-1987. Get lots of
people, preferably 120 or more.
And organize
them.
The drivers reward: A cup of hot chocolate.
Reconstructed population.
Based on jaws since 1952.
Age determined by cementum layers of
first molar for 2+ year-olds.
Aldo
Leopold
1887-1948
Father of Aldo Starker
Leopold, my Ph.D.
advisor.
Thus, I am an academic
“grandson.”
The Irruptive population model
Aldo Leopold
Population
• Deer increase to high levels the first time,
• But, the crash to low levels and,
• Return to a stable lower level thereafter.
Time
Aldo Leopold 1943. Deer irruptions. Wisconsin Conservation Bulletin 8(8):3-11.
Red Pine Plantation
1928 to 1968
White Pine Plantation
1928 to 1968
Second, plants.
I did total plant biomass and
productivity studies for the George
Reserve, but will not cover that here.
This will include only plants with a
direct connection with deer as food.
Methods for Food Intake and Digestion
Food consumption: Rumen fill
Food habits: Rumen separation, fecal
micro histological analysis
Rumen liquor: VFAs by gas chromo.
Digestibility: Artificial digestibility trials
Diet quality index: fecal N content
Woody plants in the ecotones (same
seed source) of the same age:
Vary greatly in size,
And in chemical composition.
Forest
Open
Snow
Winter snow cover
Acorns,
a real game changer
Random
Acorn Plots:
100 Total
20 Protected
Tubs
Acorn
Production
No./Sq. M.
1966
11.8
1967
nd
1968
nd
1969
nd
1970
nd
1971
nd
1972
16.59
1973
23.32
1974
14.75
1975
8.06
1976
11.83
1977
16.98
1978
0
1979
15.59
1980
20.24
1981
10.98
1982
3.77
1983
5.66
1984
12.01
1985
16.29
VFA in
Rumen
Liquer
Caloric value (Kcal/ml) for three different deer diets.
B. Coblentz, 1975
Acorns
Grass-forb
Evergreen browse
Acetic
1.164
1.358
1.215
Propionic
0.900
0.817
0.571
Butyric
0.838
0.434
0.245
Valoric
0.26 0.0
0.0
0.0
Caproic
0.239
0.0
0.0
Total
3.405
2.609
2.031
Blood EE as a percent of Dry Matter
Artificial Rumen Studies
Houghton Res. Facility 5.4%
N=25
Geo. Res. 1971-72
N=12
Rumen liquor from deer feeding on
acorns will digest almost any natural
fiber.
75.0%
Now, let’s look at social behavior again.
Importance of female matrilineal
groups, and dispersal of mainly
3.5-year-old females from these
groups.
Overlapping home ranges
Daughter 3
Daughter 2
Matriarch
Grand-daughter
1
Daughter 1
Conclusion: Yes, it is complicated.
But:
Long-term studies,
In conjunction with hypothesis tests,
Yields understanding.
So much for biology.
Management Implications:
Harvest to obtain maximum yield.
The need to harvest females to obtain
higher yields.
The on-going wars over shooting
does.
Kill 58 animals at K=178
Reduction over winter = 58 head
Spring recruitment = 45
Net decline after one year = 13 head (120 +
45 = 165)
• White-tailed deer have a large densitydependent response to harvests.
• You have to kill the hell out of them to have
much of an effect.
• You can’t skip years.
Kill 58 animals at K=178
Mule deer have less phenotypic plasticity
than white-tailed deer
• Black-tailed deer on the Pacific Coast, a
subspecies of mule deer, are rather different
from typical mule deer. They are somewhat
intermediate in plasticity, but generally were
considered nearer mule deer than whitetailed deer.
Black-tailed deer are on the N. Pacific Coast.
Fort Hunter Liggett, California
66,776 Ha
• Productivity of the George Reserve (MSY per
square Km per year = 10.8
• Productivity of Fort Hunter Liggett = 0.96
California
Coastal
Oak-Grassland
Hopland Field
Station
Hopland Field Station, California
2149 Ha Productivity 4.52
We want coyotes to love sheep.
And they do--love them to death!
Guy Connolly
Guy Connolly
Hypothesis: Doe kills will increase buck
kills
• Buck kills taken by controlled (equal effort
across years) legal hunting.
• Doe kills taken by me by illegal (efficient)
methods. DFG collecting permit.
• 20 per year for 3 years, 30 per year for 4 years.
Coyotes have greater reproductive
capacity (4-5 pups/year. Deer have 2
fawns/year).
Otherwise, their life-history traits are
similar for age at sexual maturity, life
span, etc.
Coyotes are territorial, deer are not.
Deer numbers 300
Coyote numbers 11-13
Coyotes are not able to breed without
a territory.
Mortality of coyote pups is very high.
Uniform grassland feeders; same quality.
Tule elk population rates of increase, “r”
Theoretical maximum
0.393
Owens Valley (desert)
0.139
Point Reyes (coastal)
0.171
Grizzly Island (marshy)
0.310
Great
whales
are like
elephants
Eventually data proved my case.
Thank you!
And, I’ll take your questions now.
He keeps going, and going, and…….opps,
stops!!
The End