A Work of Hope - Feral: Rewilding the Land, the Sea, and Human Life - page 146

off a fishmonger's slab. I have noticed that where large chub lurk, the
crustaceans are more reluctant to emerge from under their stones.
Twice in my crayfish nets I have trapped enormous pike - one of which
must have weighed well over twenty pounds and pulled the net all over
the river as I tried to retrieve it - though I cannot say whether they had
come after the crayfish or the bait. I would be surprised if these aquatic
locusts were not also consumed by barbel, trout and eels. It is possible
that in places where pollution levels are low enough for fish to thrive,
these predators will eventually suppress the crayfish population until it
ceases to threaten some of the native wildlife it now displaces.
Both otters and polecats, native to Europe, appear to drive Ameri-
can mink out of their territories. 75 In the Finnish archipelago the
white-tailed sea eagle, now recovering from near-extinction, also
seems to be reducing the mink's range. 76 This great eagle, recently
reintroduced, could have the same effect in Britain.
Even so, invasive species challenge attempts to defend a unique and
distinctive fauna and flora. Certain animals and plants have character-
istics that allow them to invade and colonize many parts of the world,
and there is a danger that ecosystems everywhere come to contain a
similar set of species, making the world a blander and less surprising
place. Even if they are suppressed by predators, grey squirrels and red
signal crayfish will continue to destroy their competitors (red squirrels
and white-clawed crayfish) by exposing them to the diseases they carry.
We should try to prevent them from spreading further, but accept that
they cannot be eradicated: grey squirrels, mink and signal crayfish now
belong to ecosystems from which they used to be absent, and the best
we can hope for is that they are firmly sat upon by other species.
On the day after our foray into Dundreggan, Alan took me to Glen
Affric, which is said to contain the least altered large area of wood-
land in Britain. 77 It was a bitter, wet day. From the road along the
valley of the river Affric the old forest looked like a giant tray of broc-
coli. When Scots pine is young, it is slim and pointed. But the mature
trees spread out into a broad, rounded canopy. The road wound
round bluffs to which the ancient trees clung, their crabbed and
twisted shapes reflected in the fissured rocks.