Les Écureuils Volants et Leurs Arbres
touchez, aimez la forêt ! Voilà le message que M. Brownlie nous livre.
Dans les forêts âgées, il existe une interrelation intime entre la santé des arbres
et celle de ses habitants
Dans le cas des écureuils volants, une espèce clef, les forêts leur procurent un
habitat idéal et, en échange, ils répandent une espèce de champignon qui favorise la
croissance des arbres. Malheureusement, les forêts âgées sont maintenant extrêmement
rares au N.-B., ce qui veut dire que lhabitat des écureuils volants (et beaucoup
dautres espèces !) est de plus en plus restreint. Cest un cercle
vicieux : moins il y a de forêts, moins il y a despèces et moins la
croissance des arbres est favorisée par les animaux.
Lauteur vous invite donc à être complice de la nature afin de mieux apprécier
linestimable valeur de nos magnifiques forêts.
- Big Trees
Naturalist and member of the
Fundy Environmental Action Group
hen I see a big, old tree in the
forest I say, "Wow! What a beautiful tree!" Then I put my arms around it to
measure its girth. Of course, it's also so I can rub my cheek against its old, craggy bark
without looking silly. Sometimes I lie down with my head next to the trunk and gnarly
roots, gazing way up into the branches. Obviously, I like big, old trees.
"And the widely spaced trees give them lots of room to move and escape
(photo: G. Forbes)
Flying squirrels also like big, old trees, even though they can't get their arms around
them. For them, maybe it's not so much a feeling as a need.
Everyone knows that flyers glide and this is important in escaping predators such as
marten (a large weasel) and owls. Well, in younger forests the trees are short and grow
close together. So gliding is more restricted and the chances of getting eaten are
greater. In older-growth forests, starting their glide from higher up, flying squirrels
can go further. And the widely spaced trees give them lots of room to move and escape
Older-growth forests also supply large enough trees for nest cavities where these animals
raise their young. In younger forests, flying squirrels are forced to nest in ground
cavities amongst tree roots where they have little protection from weasels.
So, older growth forests are critical, not only for flying squirrels, but also for marten,
pileated woodpeckers, owls, and plants.
Research in Fundy National Park has found that not only do flying squirrels need big, old
trees - the trees need flying squirrels!
How could a tree need a squirrel? Flying squirrels eat truffles. Truffles are the
underground fruits of some types of fungi. These fungi attach themselves to the tips of
tree roots and help the roots to absorb nutrients from the soil. So without truffles,
trees may grow more slowly and may become more susceptible to disease.
When a flying squirrel eats a truffle, the truffle's spores (seeds) are deposited on the
forest floor in the squirrel's droppings and grow into more truffles. So every time a
squirrel eats a truffle, it helps plant more truffles and keep trees healthy and growing
Today, our natural older-growth forests are being cut and replaced by tree plantations
made of single types of trees. Thus we risk losing about 25 species of birds and mammals
which depend upon older-growth forests for their survival. But the loss of flying
squirrels is particularly devastating. Flying squirrels are called a keystone species.
They help keep the forest healthy by spreading truffle spores. When flying squirrels
disappear from the forest, the trees may grow more slowly and may die, thus jeopardizing
the whole ecosystem and all the plants and animals in it.
"What can we do? Go out into natural forests and hug big trees!"
(photo: B. Townsend)
So we need to change the way we harvest our forests. Instead of just maximizing the
production of timber, we must think about how to conserve enough habitat in New Brunswick
for flying squirrels.
For example, the provincial government's forest policies now require forestry companies
cutting on Crown lands to keep 10% of the softwood forests in an older condition. Also, in
1992, New Brunswick agreed to establish a network of protected areas. Although government
staff had identified 54 potential sites, only part of one has been officially set aside.
What can we do? Go out into natural forests and hug big trees! The more time we spend
observing nature, hugging big trees, the more we will appreciate what we have left. You
can join a local naturalist group and participate in projects to monitor birds, frogs, and
beetles. Enjoying nature leads to appreciation and support for those groups fighting to
conserve habitats and wildlife that live there.
You may even decide to write your MLA or the Premier to let him/her know you want action
to conserve older growth forests in New Brunswick.
You can click here to send mail to Premier