stands on the taiga winter range of the Beverly cari- ... adjacent Beverly caribou population with emphasis ... these light burn years with the large burns of other.
Other papers T h e f o l l o w i n g p a p e r b y D o n M i l l e r was p r e s e n t e d , s u b m i t t e d , r e v i e w e d a n d a c c e p t e d b y the editors o f the 7 t h N o r t h A m e r i c a n C a r i b o u C o n f e r e n c e i n T h u n d e r B a y , O n t a r i o . R e v i s i o n s a r r i v e d too late to be i n c l u d e d i n those p r o c e e d i n g s .
W e have i n c l u d e d t h e m i n these p r o c e e d i n g s
organizers. D o n Russell R i c k Farnell D e b b i e v a n de W e t e r i n g
as a courtesy
to the T h u n d e r
Bay
The Seventh N o r t h A m e r i c a n Caribou Conference, Thunder Bay, Ontario, Canada, 19-21 A u g u s t , 1996
Lichens, wildfire, and caribou on the taiga ecosystem of northcentral Canada Don Miller M i l l e r and M i l l e r W i l d l i f e Consultants, 156 Concord R d „ Lee, N H 0 3 8 2 4 - 6 6 3 1 , U S A . Abstract: Terrestrial lichens are unique organisms that are pioneers on bare sand and rock, survive desiccation and reproduce both sexually and asexually. They compete poorly w i t h dense, aggressive vascular flora. W i l d f i r e s require organic matter as fuels, are the driving force i n perpetuation of the Taiga Ecosystem i n a heterogeneous environment and, i f left alone, are self controlling. Caribou w i n t e r i n g on the T a i g a are dependent on: (1) a terricolous lichen forage supply for most of the winter, (2) a heterogeneous environment to cope w i t h predators and the changing nival environment, and (3) natural wildfires to supply these needs. W i l d l i f e control on the Taiga winter range is not recommended as a m a n agement tool for barren-ground caribou. K e y w o r d s : c a r i b o u m a n a g e m e n t , forage use, forest fire, Rangifer,
s n o w cover, w i n t e r range.
Rangifer, S p e c i a l Introduction
Issue N o . 12, 1 9 7 - 2 0 7
a n d h a d n o t increased i n recent years as a r e s u l t o f
Science is a search for t r u t h , b u t i t c e r t a i n l y
has
h u m a n caused fires, as p r o p o s e d b y S c o t t e t ( 1 9 6 4 ) .
been d i f f i c u l t to i d e n t i f y w h a t is fact a n d w h a t is fic-
T h e y c o n c l u d e d that the c a r r y i n g c a p a c i t y o f t h i s
tion
w i n t e r range o f the B e v e r l y c a r i b o u p o p u l a t i o n was
i n the
controversial
subject
o f forest
fires,
lichens, and w i n t e r i n g barren-ground caribou on the
t a i g a of n o r t h c e n t r a l
Schandelmier,
1980).
C a n a d a (see
There
was
Viereck
nothing
&
m u c h the same as it h a d b e e n for c e n t u r i e s . The
barren-ground
caribou
populations
in
wrong
C a n a d a c o n t i n u e d to d e c l i n e t h r o u g h the 1 9 5 0 s a n d
w i t h the o r i g i n a l s u g g e s t i o n that forest fires o n the
h a d n o t s h o w n a n y i m p r o v e m e n t b y the m i d d l e o f
t a i g a m a y have c o n t r i b u t e d to a r a p i d d e c l i n e
of
the 1 9 6 0 s d e s p i t e a n intense a n d c o s t l y w o l f c o n t r o l
caribou populations i n northcentral Canada i n the
p r o g r a m a n d a m u c h r e d u c e d a n n u a l harvest o f c a r i -
m i d d l e of the t w e n t i e t h c e n t u r y ( B a n f i e l d , 1 9 5 4 ) ,
b o u b y n o r t h e r n residents. I n o r d e r to
a n d it c e r t a i n l y was p r o p e r to a s s i g n a range e c o l o -
answers t o w h y these c a r i b o u p o p u l a t i o n s
g i s t to the job o f s t u d y i n g the r e l a t i o n s h i p o f forest
responding
fires o n the t a i g a a n d the effect o n d e c l i n i n g c a r i b o u
research
p o p u l a t i o n s (Scotter,
When
K a m i n u r i a k caribou p o p u l a t i o n (renamed i n
i n the
the Q a m a n i r j u a q c a r i b o u p o p u l a t i o n ) . F o u r separate
1964;
Scotter r e p o r t e d a n increase
1965;
1970).
o f forest
fires
to
management
p r o g r a m was
efforts
initiated i n
find
an 1966
some
weren't intensive on
the 1989
t a i g a d u r i n g the m i d d l e o f the present c e n t u r y c o m -
b i o l o g i c a l studies were c o n d u c t e d
p a r e d w i t h the p r e v i o u s century, a n d it's i n f l u e n c e
and cooperatively between
o n the p r e f e r r e d l i c h e n forage
supply of caribou
one c a r i b o u p o p u l a t i o n that calves i n the v i c i n i t y o f
1 9 6 6 ) , there appeared t o be a p l a u s i -
K a m i n u r i a k Lake, N o r t h w e s t Territories and usual-
ble cause for the p o p u l a t i o n d e c l i n e . H o w e v e r , it
l y w i n t e r s i n the t a i g a o f n o r t h w e s t e r n M a n i t o b a ,
(Scotter 1 9 6 4 ; was
later
that
Scotter's h y p o t h e s i s
simultaneously
to 1 9 6 9
on this
was
northeastern Saskatchewan and southern N o r t h w e s t
forest
T e r r i t o r i e s ( M i l l e r & R o b e r t s o n , 1 9 6 7 ) . O n e o f these
stands o n the t a i g a w i n t e r range o f the B e v e r l y c a r i -
f o u r studies was o n the t a i g a w i n t e r range r e l a t i o n -
incorrect
reported
1966
because the m e t h o d used to age
b o u p o p u l a t i o n was biased to recent forest
fires
ships w h i c h revealed that c a r i b o u u t i l i z e d a w i d e
(Johnson & R o w e , 1975). Johnson & R o w e reported
v a r i e t y o f habitats
that forest fires i n the w i n t e r range o f the B e v e r l y
w i t h the c h a n g i n g w i n t e r seasons a n d n i v a l charac-
c a r i b o u p o p u l a t i o n were m o s t l y caused b y l i g h t n i n g
teristics o n the t a i g a of n o r t h c e n t r a l C a n a d a ( M i l l e r ,
Rangifer,
S p e c i a l Issue N o . 12, 2 0 0 0
a n d w i n t e r forages
associated
197
1974). Formosov (1946) and N a z i m o v i c h (1955)
users r e q u e s t e d forest fire c o n t r o l to p r o t e c t the bar-
had reported
r e n - g r o u n d caribou's w i n t e r range ( T h o m a s
s i m i l a r n i v a l characteristics
on
the
et
taiga i n Russia. M i l l e r (1976a) reported that w i l d -
1 9 9 6 ) . A s a response to t h i s request a n o t h e r
fires o n the t a i g a were essential to m a i n t a i n a h e t -
was
erogeneous e n v i r o n m e n t ( m o s a i c o f e n v i r o n m e n t s i n
Beverly
Heinselman,
1973)
in w h i c h caribou could
find
initiated on
the
taiga
winter
caribou population i n
al.,
study
range o f
the
1982-1986. As a
result o f t h i s s t u d y a fotest fire c o n t r o l p r o g r a m was
s u i t a b l e forage a n d escape h a b i t a t d u r i n g any n i v a l
p r o p o s e d s p e c i f i c a l l y for the
c o n d i t i o n s t h e y m a y be s u b j e c t e d to o n the
area w i n t e r range o f the B e v e r l y a n d Q a m a n i r j u a g
taiga
during winter. At
the
taiga and
caribou populations (Thomas,
c o n c l u s i o n o f the
Kaminuriak
p o p u l a t i o n study, M i l l e r was g i v e n the
caribou
assignment
b y his e m p l o y e r , the C a n a d i a n W i l d l i f e Service, s t u d y the t a i g a w i n t e r range r e l a t i o n s h i p s
to
o f the
transition
1994).
T h e s c o r c h i n g o f the large acreage o n the
taiga
a n d the t r a n s i t i o n zone w i n t e r range o f the B e v e r l y c a r i b o u P o p u l a t i o n , as r e p o r t e d u n u s u a l for t h i s area ( J o h n s o n
in
1979,
is
not
& R o w e , 1975). In
adjacent B e v e r l y c a r i b o u p o p u l a t i o n w i t h
emphasis
s o m e s u m m e r s , p r a c t i c a l l y n o t h i n g is b u r n e d i n this
o n the i n f l u e n c e o f w i l d f i r e s . T h i s p a p e r
includes
p a r t i c u l a r w i n t e r range area a n d the c o m b i n a t i o n o f
b o t h the second t a i g a w i n t e r r a n g e s t u d y , w h i c h was
these l i g h t b u r n years w i t h the large b u r n s o f o t h e r
r e p o r t e d as a d i s s e r t a t i o n ( M i l l e r , 1 9 7 6 b ) a n d s u m -
years, l i k e i n 1 9 7 9 , average o u t to a b o u t one p e r c e n t
marized
scorched annually ( W e i n & M a c L e a n , 1983).
at
the
second
International
Reindeer/
C a r i b o u S y m p o s i u m ( M i l l e r , 1 9 8 0 ) ; a n d the i n i t i a l study
of
(Miller,
the
Kaminuriak
1974;
caribou
1976a). Essentially
population
the
results
these t w o w i n t e r range studies agreed w i t h sive studies
an
essential
dominance
component
i n terrestrial
lichen
o f the g r o u n d cover i n m u c h o f
the
exten-
t a i g a . A l s o u s i n g d a t a c o l l e c t e d i n the 1 9 6 0 s a n d
caribou
early 1 9 7 0 s o n the t a i g a o f n o r t h c e n t r a l C a n a d a , i t
and i n N e w f o u n d l a n d of w o o d l a n d
shows h o w w i l d f i r e s v a r y b e t w e e n years, w h a t p o r -
c a r i b o u ( B e r g e r u d , 1 9 7 1 ; 1 9 7 2 ) t h a t w i l d f i r e s i n the
t i o n o f areas w i t h i n the m a r g i n o f the b u r n e d areas
t a i g a d i d n o t appear to i n f l u e n c e these p a r t i c u l a r
a c t u a l l y was i g n i t e d , a n d w h a t role w i l d f i r e s p l a y i n
caribou populations.
the p e r p e t u a t i o n o f t e r r e s t r i a l l i c h e n s . F i n a l l y , also
(Skoog,
i n A l a s k a of barren-ground
of
T h i s p a p e r a t t e m p t s to s h o w t h a t these w i l d f i r e s are
1968)
During
the
m i d a n d late
1 9 7 0 s there were
a
using
field
observations
i n the
1960s and
1970s d u r i n g
dence o f forest fires a n d o n the e x i s t i n g t e r r i c o l o u s
g r o u n d c a r i b o u i n h a b i t the t a i g a , i t w i l l be s h o w n
fruticose l i c h e n flora i n the t a i g a a n d adjacent t r a n -
h o w c a r i b o u u t i l i z e d b o t h the b u r n e d a n d u n b u r n e d
s i t i o n zone ( b e t w e e n t a i g a a n d t u n d r a ) i n N o r t h
habitats
America (Rowe
l i c h e n a n d n o n - l i c h e n forage s u p p l i e s i n response to
Johnson 1976;
&
& Scotter,
Rowe,
1975;
Viereck,
1973;
Makinow &
Kershaw, 1977; Johnson,
1979,
1973;
Kershaw,
a n d others).
the v a r i o u s w i n t e r seasons
early
n u m b e r o f i m p o r t a n t papers p u b l i s h e d o n the i n c i -
feeding
on
terrestrial
a continuously changing
lichens,
arboreal
nival environment.
paper a t t e m p t s to s h o w h o w a successful control
o f fire m a d e p a r t i c u l a r reference t o n o r t h e r n C a n a d a ,
C a n a d a , as p r o p o s e d b y T h o m a s ( 1 9 9 4 ) , w o u l d u l t i -
a n d one
mately
by Viereck
& Schandelmeier Klein
(1980) i n
(1982) i n a
reduce
in
rather
the than
taiga
of
The
wildfire
A r e v i e w p a p e r b y K e l s a l l et al. ( 1 9 7 7 ) o n the effects
A l a s k a a n d adjacent C a n a d a .
program
barren-
northcentral
increase the
carrying
c a p a c i t y for w i n t e r i n g b a r r e n - g r o u n d c a r i b o u . A n d
review paper entitled, "Fire, Lichens and C a r i b o u , "
finally
c o n c l u d e d t h a t there were l o n g t e r m benefits f r o m
c a r i b o u m a n a g e r s need to m o n i t o r the
fire
h u m a n p o p u l a t i o n increase a n d a c t i v i t i e s
on
the
taiga
and
short
term
consequences.
the paper c o n c l u d e s
w i t h a proposal
that
effects in
of the
B u n n e l l et al. ( 1 9 7 5 ) r e p o r t e d o n a c o m p u t e r s i m u -
t a i g a t h a t can seriously t h r e a t e n w i n t e r i n g c a r i b o u .
lation study involving Canadian W i l d l i f e
W i l d f i r e m a y b r i e f l y c h a n g e h o w c a r i b o u use
Service
the
c a r i b o u b i o l o g i s t s w h o h a d s t u d i e d or were s t u d y -
taiga b u t people and their activities w i l l eventually
ing barren-ground caribou populations i n northcen-
d e t e r m i n e w h a t p o r t i o n o f the t a i g a w i l l be a v a i l -
t r a l C a n a d a . T h e y c o n c l u d e d t h a t a n increase o f f o r -
able for w i n t e r use b y c a r i b o u .
est
fires
b y five t i m e s
the n o r m a l
1
percent
per
a n n u m w o u l d have " l i t t l e effect o n the p o p u l a t i o n . " In
1979,
however,
a reported
1
1/4
million
Lichen Ecology L i c h e n s are u n i q u e o r g a n i s m s
i n m u c h o f the t a i g a , e s p e c i a l l y
the
ground
s i t i o n zone o f n o r t h c e n t r a l C a n a d a a n d the c a r i b o u
x e r i c , sandy soils. M o s t o f the u p l a n d s i n the t a i g a
198
flora
that d o m i n a t e
hectares were b u r n e d i n the t a i g a a n d adjacent t r a n -
Rangifer,
on
S p e c i a l Issue N o . 12, 2 0 0 0
a n d t r a n s i t i o n zone o f n o r t h c e n t r a l C a n a d a is c o m -
A n o t h e r characteristic
about
l i c h e n s that
is
of
posed o f a x e r i c , w e l l - d r a i n e d , p u r e s a n d m a n t e l .
m a j o r i m p o r t a n c e to c a r i b o u - b e s i d e s taste, n u t r i t i o n
(Ritchie,
pioneer
a n d a b u n d a n c e - is the species or g r o u p s o f species
relationship
a v a i l a b l e for f o r a g i n g . T h i s i n v o l v e s the successional
1962;
organisms
that
Argus,
1966)
are
a
in
They
are
symbiotic
b e t w e e n a f u n g a l ( m y c o b i o n t ) and one or m o r e a l g a l
sequence f o l l o w i n g d i s t u r b a n c e ,
(photobiont)
T h e r e are m a n y w i l d l i f e b i o l o g i s t s , ecologists
components
( H a l e , Jr.,
1996). T h e p r i m a r y charactenstic
1967;
Nash,
of lichens
that
s u c h as
wildfire.
l i c h e n o l o g i s t s w h o have r e p o r t e d o n t h i s
and
subject,
p e r m i t s t h e m to d o m i n a t e the g r o u n d f l o r a i n the
a n d m a n y are g o o d for areas s t u d i e d . T h e best g e n -
taiga
eral d e s c r i p t i o n o f t h e l i c h e n flota i n m y o p i n i o n is
is that
which
they
destroys
can s u r v i v e severe
vascular
flora
and
desiccation most
other
bryophytes.
b y A h t i ( 1 9 7 7 ) , w h o has n u m e r o u s p u b l i c a t i o n s o n c a r i b o u range i n N o r t h A m e r i c a ( A h t i , 1 9 5 9 a ; b ;
L i c h e n s d o m i n a t e the g r o u n d flora i n m u c h o f the
1 9 6 4 ; A h t i & H e p b u r n , 1967)
and r e i n d e e r ranges
t a i g a u n t i l an a c c u m u l a t i o n of o r g a n i c m a t t e r w i t h
i n S c a n d i n a v i a ( A h t i , 1 9 6 1 a ; b; A h t i et al.,
its m o i s t u r e r e t e n t i o n characteristics occurs o n the
F o l l o w i n g is his g e n e r a l sequence o f t h i s l i c h e n suc-
surface o f the sandy soils. T h i s r e t e n t i o n o f w a t e r i n
cession
the a c c u m u l a t e d
1977)
plants
to
organic
become
matter
established
expense o f the l i c h e n
permits
and
vascular
t h r i v e at
the
flora.
to as the sparsely treed t a i g a stands o n u p l a n d sites o f b l a c k spruce {Picea mariana)
a n d jack p i n e
(Pinus
e i t h e r alone or i n c o m b i n a t i o n s , w i t h a
d o m i n a n t g r o u n d cover o f l i c h e n s . T h e s e are
the
l i c h e n w o o d l a n d s i n the t a i g a that are
important
caribou
especially.
feeding
sites,
"Boreal
Coniferous
true g e n u s a n d therefore uses
in
mid-winter
oligotropha, L. uliginosa 3. C u p l i c h e n stage,
a n d L. granulosa
the l o w l a n d m u s k e g s a n d also g r o w o n the
slopes
w h i t e b i r c h (Betulapapyri/era).
These esker sites m a y
be
especially
but
the
south
dominant.
years after
d o m i n a n t (e.g. C.
nuta var. cornuta, C. gracilis var. dilata,
C.
fire; cor-
crispata,
C. gonecha) 4. F i r s t reindeer l i c h e n stage, 30 (-50) rangiferina
a n d tops o f eskers, w h i c h are often sparsely treed by
(-50)
s u b g e n . Cladonia
Cladonia
g r o w i n dense mats. T h e y g r o w o n h u m m o c k s i n
all winter,
as a
Cladonia):
10-30
years after fire; Cladonia
on
(Ahti,
2. C r u s t o s e l i c h e n stage, 3 - 1 0 years after fire; Leadea
H o w e v e r , these are not the o n l y sites w h e r e l i c h e n s
fed
Zone"
or taiga. ( A h t i does not accept Cladina
1. B a r e s o i l stage, 1-3 years after fire.
L i c h e n w o o d l a n d is w h a t has often been referred
banksiana),
i n the
1968).
a n d C. uncialis
Since
I have
(-120) C,
dominant.
5. S e c o n d reindeer l i c h e n stage 8 0 years after fire; Cladonia
-80
m i t i s , C. arbuscula, (120)
or m o r e
stellaris d o m i n a n t .
i n c l u d e d this
lichen
successional
exposed slopes a n d o p e n tops are u t i l i z e d b y f o r a g -
sequence v e r b a t i m f r o m A h t i ( 1 9 7 7 , p . 165), I m u s t
i n g c a r i b o u i n late w i n t e r a n d s p r i n g w h e n t h e s u n
also g i v e his f o l l o w i n g s t a t e m e n t :
b e g i n s to m e l t s n o w o n exposed sites ( M i l l e r , 1 9 7 4 ) .
"It s h o u l d be n o t e d that the t i m e t a b l e o f t h i s suc-
B a r e patches also appear i n the snow cover o n w i n d -
cession
swept o p e n i n g s a n d i n f e e d i n g craters, p r e v i o u s l y
r e g i m e a n d the c l i m a t i c p o s i t i o n o f the s t a n d , a n d
excavated b y c a r i b o u . T h e n o r t h a n d east slopes ate
different
u s u a l l y s t i l l u n a v a i l a b l e for f o r a g i n g at t h i s
side b y side (Jalas & V a l p a s , 1 9 6 2 ) . "
time
because o f deep, d r i f t e d snow. How
do
terricolous,
from disturbances
fruticose
is g r e a t l y
dependent
rates o f succession
H e also c o m m e n t s lichens
recover
u p o n the m a y be
on "somewhat
moisture
encountered mesic
lichen
forests ( r e c o g n i z e d b y a t h i c k e r h u m u s l a y e r ) " rhat
like caribou cratering, foraging
" t h e r e m a y be a stage of very dense, y o u n g forest,
a n d t r a m p l i n g a c t i v i t y ? L i c h e n s are w e l l a d a p t e d to
w h e n l i c h e n s are t e m p o r a r i l y i n d e c l i n e and even
this k i n d o f c a r i b o u a c t i v i t y i n the presence of a
absent, a l t h o u g h they appear a g a i n w h e n the c l i m a x
s n o w cover because o f t h e i r characteristic o f g r o w -
is a p p r o a c h e d . " A h t i also states, i n the same p u b l i -
i n g n e w p o d e g i a w h e n f r a g m e n t e d or d i s l o d g e d (see
c a t i o n , that there is " . . . a Stereocaulonpaschale
Webb,
some
1998).
This
is
exceedingly
important
continental
because i t p e r m i t s l i c h e n s to not o n l y s u t v i v e c a r i -
(Ahti,
b o u f e e d i n g a c t i v i t y i n w i n t e r , a n d man's foot steps
1 9 5 9 ) , b u t its e c o l o g i c a l
b a c k g r o u n d is n o t
well
w h e n the l i c h e n s ate d r y a n d b r i t t l e i n s u m m e r , b u t
u n d e r s t o o d . " T h i s l i c h e n species is d i s c u s s e d
later
to b e c o m e e s t a b l i s h e d on favorable substrate w h e n
u n d e r the h e a d i n g o f C a t i b o u , L i c h e n a n d N o n -
transported
l i c h e n Forage R e l a t i o n s h i p s .
b y w i n d a n d w a t e r or b y
mammals,
1961a)
stage i n
areas, s u c h as w e s t e r n L a p l a n d
and
northern
Manitoba
(Ritchie,
b i r d s a n d insects.
Rangifer,
Special Issue N o . 12, 2 0 0 0
199
Table 1. Area burned d u r i n g a 16-year interval i n northcentral Saskatchewan and during 12 years i n northwesteri Manitoba as determined from colored aerial photographs compared w i t h previous panchromaric aerial pho tographs. Hectares land
Hectares
Years o f aerial p h o t o g r a p h y
surface i n t e r p r e t e d
burned
(# o f years)
Number
Annual burn
(%)
o f fires
Saskatchewan
575
687
63
411
1955 & 1972
(16)
0.7
41
Manitoba
982
701
19
230
1955 & 1967
(12)
0.2
47
I
R o w e ( 1 9 7 5 ) a n d V i e r e c k ( 1 9 7 3 ) c o m m e n t e d o n th