My first
Zeiss-brand binoculars were so good they could pick up – in sharp focus –
clumps of purple loosestrife growing in narrow marshlands on the shore of the
Susquehanna River below the Council Cup promontory. From where I stood atop the
rocky point, the distance was a good half mile.
It was the
chance to see migrating raptors – birds of prey – that attracted me to the big
rock pile a couple of miles upstream of Berwick. After all, Council Cup was
much closer to home – Conyngham – than the very well known Hawk Mountain
Sanctuary.
And there
they were: Broad-winged hawks, American kestrels and peregrine falcons in
September, bald eagles and ospreys in October and red-tailed hawks and other
species in early November.
It was
loosestrife that I thought of today, though, when I picked up my just-acquired
copy of the new book Invasive Species and
Global Climate Change.
Invasive,
exotic (i.e., non-native) plants are, in themselves, bad enough for the future
of our natural heritage. But we’re making things much harder to fix with our
unrelenting burning of gunk fossil fuels.
Even folks
who care only about the dollar bill and related economic matters should care
and support efforts to take action. Here’s why: Non-native invasive plants and
animals are taking over ecosystems in every state, crowding out habitat for
native species and costing billions of dollars in control efforts and lost
productivity. In the case of just one invasive – loosestrife – the effects of
its invasion are long-lasting.
It destroys
wetland habitat. Period.
The U.S.
Fish and Wildlife Service offers this assessment: “The impact of thriving
non-native species can be devastating to the environment. Non-native plants
that propagate and become invasive can have tremendous negative impacts—both
ecologically and economically. An estimated 5,000 alien plants exist in
the United States, displacing native species. One example is the European
purple loosestrife. It has been spreading at a rate of 115,000 hectares a year
and has been blamed for reducing the biomass of 44 native plants and endangered
wildlife, including bog turtles and several species of ducks that depend on the
native plants.
“Loosestrife
now occurs in 48 states and costs $45 million per year in control costs and
forage losses.”
Our planet’s
changing climate (again, don’t confuse the daily weather with “climate”), is
hastening the spread of invasive plants and animals to places where they are
invaders, not natives.
The
Pennsylvania Department of Conservation and Natural Resources, the agency that
looks after our state parks and other public lands, says this: “Climate change
adaptation is preparing for and responding to the impacts of climate change.
While reducing greenhouse gases, a process referred to as mitigation, is
essential, it won’t prevent the inevitable changes resulting from to the
greenhouse gases already in atmosphere. Consequently, we need to begin
developing strategies to deal with both the direct and indirect effects of
climate change.”
A Google
search turned up scores of papers and other documents discussing how warmer
temperatures will aid and abet the spread of weedy invasive plants. One that
looks at what is happening in the mid-Atlantic region can be read at www.fws.gov/northeast/climatechange/conference/pdf/235pm_dr_lew_ziska.pdf
In all-day
hikes across Pocono wild lands in the late 1990s, finding a clump or more of
loosestrife and other invasive species like Japanese knotweed was a no-brainer.
These and other alien plants take quick advantage of human activities like
road-building and other development.
What can
nature-watchers do to help?
-
Learn
to identify invading plants and animals;
-
Take
care not to spread them into new areas;
-
Report
invaders to a land manager;
-
Volunteer
to assist with removal or control programs.
Finally, tell the person who represents you in state and
federal governments to take positive action, not to kowtow to moneyed special
interests.
