10 Apr 2007 - My name
is Van Beacham and I am 49 years old. I
live in northern New Mexico. I come from
four generations of fly fishermen. I have
been fishing since I was 6 years old and
have been guiding fishing trips throughout
the west since I was 22. I have been a professional
fly fishing guide in southern Colorado and
south-west Wyoming.
I have been witness to many of the effects
that warmer temperatures are having on the
river systems and the fish that depend on
them.
As a kid I remember the wet cycle when
we had greater than average snow pack and
lower temperatures. This was from about
1970 up into the 11000s when the snow stuck
around all winter long. We never had spikes
of 60ºF (16ºC) degree weather
in January like we do now.
Some of these wet/dry cycles we know are
natural. What is different over the last
ten years or so is that temperatures are
way above what we ever saw before. Around
Albuquerque, New Mexico, for example, we’ve
lost a month of winter — a month of time
between the last frost and the first frost.
In the Rocky Mountain west and further
north there has been even more changes.
At high elevation (greater than 5000-7000
feet, or 1500-2100 metres) I’ve been seeing
temperatures 5-10ºF (2-5ºC), sometimes
even 25ºF (12ºC), warmer than
average.
Earlier snow pack runoff
We are losing snow in a time of year when
we should be gaining it. This has been the
story for the last 8-10 years, and it’s
getting worse and worse. Recently, we had
lots of snow — slightly above the average
— but it was so warm that the runoff happened
much faster than normal and was over by
June and July. The rivers were all raging
and, instead of a slow sustained runoff,
they peaked violently and then dropped down
to a trickle by early summer.
Some streams and small rivers have been
drying up completely. I believe that some
of these patterns can be explained by the
natural drought cycle that we are in. Also,
there is continued pressure from development
in some areas. But, how do you explain the
fact that, in four generations, none of
these streams have ever dried up?
I think you have to look at the consistent
warmer temperatures that we’ve been having
and recognize that what’s going on is an
interaction between drought, development
and global warming.
Effects on Fish
When the low stream flows combine with warmer
temperatures, the fish really take a hit.
For example, the spawning season has been
changing because the fish won’t spawn when
the water is too hot. The timing of the
aquatic insect hatchings has also changed
and for wild trout, these insects are really
important.
I used to go out fly fishing a lot in the
middle of summer — July and August were
our busiest times. But now the fish are
literally so sluggish that they can’t feed.
During the last few years, some parts of
Montana have been closed for fishing in
July and August. The fish were just too
stressed and some were dying. Water temperatures
greater than 70ºF (21ºC) starts
to kill fish.
Algal blooms, increased sediment loading
and more aquatic weeds are all things I’ve
been noticing more and more. These changes
hurt the fish and it takes a toll on the
wild trout first. In the lower reaches of
some of the streams I fish, only the brown
trout are hanging on. There is also another
shift going on. In some areas the cold water
loving trout are disappearing altogether
and are being replaced by small mouth bass,
which can tolerate warmer water temperatures
than trout.
Consequences
Low stream flows and increased water temperatures
have become a double-whammy for the trout
fisherman. As a fishing outfitter, I’ve
had to reposition the way that I guide.
I’ve learned to lease private waters that
are either higher up in elevation or below
dams so that I can have a long enough season.
I don’t fish in the summer much at all and
winter fishing is becoming more popular.
Overall, the last five years business has
been down.
People won’t pay me to take them out bass
fishing. Folks can fish for bass in a lot
of lakes and reservoirs around the country
— It’s the fly fishing for wild trout that
draws people to these mountain streams.
Sometimes I tell my clients things they
don’t always want to hear. I’m honest about
why the fishing is poor in some areas and
I feel it’s my duty to talk about the problems.
I let people know that we’re partly responsible
for the warming of the globe. This shocks
some people. Before, many of them did to
not believe that humans have a role in climate
change, but now folks are starting to understand
this relationship and are seeing the big
picture.
Scientific background
Since the 1940s, temperatures in western
North America have increased by 1-2°C,
primarily during the winter and spring months.
Studies have shown that higher winter and
spring temperatures have resulted in earlier
snowmelt by 1-4 weeks (relative to the 1950s
through the 1970s).
Though some aspects of this change can
be explained by natural cycles of climate
variability in the western region of the
US, scientists have determined that the
scope of the change goes beyond these natural
cycles. If early snowmelt continues, because
of climate change, it will greatly affect
the water resources throughout the western
US.
