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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