Great Lakes Record Lows

  • Lower water levels on the Great Lakes make some channels such as the Muskegon River too shallow for big freighters to enter fully loaded. (Photo by Lester Graham)

The Great Lakes are hitting new record low water levels. The water is so low that
big 1000-foot cargo ships are running aground. There’s debate about
whether this is just part of the historic ups and downs of the Great Lakes, or if it’s the
effects of global warming. Lester Graham reports from Lake Michigan’s Muskegon
River, a trouble spot for some of the big ships:

Transcript

The Great Lakes are hitting new record low water levels. The water is so low that
big 1000-foot cargo ships are running aground. There’s debate about
whether this is just part of the historic ups and downs of the Great Lakes, or if it’s the
effects of global warming. Lester Graham reports from Lake Michigan’s Muskegon
River, a trouble spot for some of the big ships:


Here at the end of the pier next to the lighthouse, it’s cold, it’s icy and it’s windy. And
it’s hard to imagine a ship navigating its way into this channel, but ships do on a
regular basis to bring coal to a power plant. This year, however, some of the ships
have ended up aground here simply because of lower lake levels and more sediment
in the channel:


“There’s been three this summer here in Muskegon. They go hard up on the sand.”


Dennis Donahue is the marine superintendent for the National Oceanic and
Atmospheric Administration’s Lake Michigan field station at Muskegon, Michigan. He
says this year’s groundings of cargo ships just hasn’t happened that often in the
past:


“Well, we haven’t had a grounding here, certainly in the last 15 years due to water
levels.”


Lester Graham: “So what’s happening here? What’s going on?”


Donahue: “Well, there’s a couple of things, we’ve got the water levels dropping and
then we’ve got some weather patterns that are carrying sediment to the mouth of the
Muskegon River. So, those two compound and create shoal areas.”


So lower water and a rising bottom mean channels are more shallow. That means
ships have to carry less cargo, and that costs the shippers reportedly a million
dollars per ship per year.


Scientists have been monitoring the dropping lake levels for close to a decade now.
At NOAA’s Great Lakes Environmental Research Lab, Deputy Director Cynthia
Sellinger says she’s been seeing a trend in the weather that’s causing the problem:


“We’re having a lot less precipitation and a lot more evaporation. And that’s
impacting the water levels on the lake.”


Less snow pack and rain mean less water filling the lakes, and with warmer winters
Sellinger says there’s less ice cover to protect the lakes from massive evaporation.
Historically, about 50% of the lakes’ surfaces have been covered by ice. These
days, it’s more like ten to 20%. Cold air hits the warmer water and
carries it away. For Lake Superior alone, a one-inch drop is more than 500 billion
gallons. During the past decade, Superior has lost nearly 13 trillion gallons.


“The upper lakes, Superior, Michigan and Huron, are very close to their record low.
So, it’s approaching an extreme. Superior reached its record low in 1926 and just
this year it broke the record low for September. So, 2007 now is a new record low
for Lake Superior. Lakes Michigan and Huron are approaching their record low.”


Sellinger and her colleagues are not ready to say global warming is causing the
lower lake levels. It might just be a part of a long cycle of ups and downs of the lakes.
But the lower water levels do fit some of the computer model predictions about
global warming.


Lower lake levels causing problems for big cargo ships and marinas catering to
recreational boaters are problems enough. But, some environmentalists say if lower
water levels are caused by global warming, the pressures on the water in the Great
Lakes likely are going to get a lot worse. Andy Buchsbaum heads up the National
Wildlife Federation’s Great Lakes office:


“The hidden threat of global warming is that not only does it affect Great Lakes water
levels simply because of increased evaporation or increased temperatures changes
precipitation, but the threat it makes to Great Lakes water levels is even greater.
Because global warming, global climate change, is having massive effects already
and is likely to have even greater effects on water supplies in the Southwest, the
Southeast and all over the country. And as those pressures increase, the pressure
to divert Great Lakes water will increase exponentially.”


We don’t know whether new diversions to dry areas of the country could cause as
much of a problem as less precipitation and more evaporation of the Great Lakes
already do. But, it would certainly aggravate the problem. The effects of water
levels dropping further mean more economic hardship for shipping and tourism. And
environmentalists say ecological damage to coastal habitat that fish and other
wildlife need to survive could be on a scale that’s not been seen on the Great Lakes
in recorded history.


For The Environment Report, I’m Lester Graham.

Related Links

Study Identifies Epicenters of Extinction

Extinction is a natural process. But scientists point out that humans have sped that process up. A new study maps out the places on Earth where species are in the greatest danger of going extinct. The Great Lakes Radio Consortium’s Rebecca Williams reports:

Transcript

Extinction is a natural process, but scientists point out that humans have
sped that process up. A new study maps out the places on earth where
species are in the greatest danger of going extinct. The Great Lakes Radio
Consortium’s Rebecca Williams reports:


Conservation biologists are most concerned about endangered animals and
plants that are confined to just one location on earth, such as one
mountaintop, one lake, or one farm.


A new study finds there are close to 800 endangered species worldwide that
are found in single remaining sites.


Taylor Ricketts is the lead author of the study published in the
Proceedings of the National Academy of Sciences. He says historically, most
extinctions have been on islands, but the species at risk now are found more
often on the mainlands.


“And I think that’s because our footprint on the mainlands has just grown,
and our habitat conversion of a lot of these places has intensified so much
that even the not particularly susceptible species are beginning to be
threatened with extinction.”


Ricketts says two thirds of these isolated sites don’t have full legal
protection. He points out it’s hard to protect species that are on land
with competing uses, such as agriculture, timber harvest or houses.


For the GLRC, I’m Rebecca Williams.

Related Links

Rushing to Save Native Mussels

  • Michigan researchers are searching rivers and lakes for evidence of the native Purple Lilliput (pictured above). Photo by Doug Sweet.

In recent years, a great deal of attention has been focused on zebra mussels. They’re not native to the Great Lakes region and they’re pushing native mussels out of local lakes and streams. As the Great Lakes Radio Consortium’s Celeste Headlee reports, one scientist at a Detroit Aquarium has taken on the daunting task of trying to save a small, rare native mussel from disappearing in the state:

Transcript

In recent years, a great deal of attention has been focused on
zebra mussels. They’re not native to the Great Lakes region
and they’re pushing native mussels out of local lakes and streams.
As the Great Lakes Radio Consortium’s Celeste
Headlee reports, one scientist at a Detroit Aquarium has taken
on the daunting task of trying to save a small, rare native
mussel from disappearing in the state:


(ambient sound throughout – whenever Doug Sweet talks)


At a small pond near a highway, biologist Doug Sweet and his team put on waders and wet suits
and prepare to enter the sluggish brown water of Dawson’s Millpond Outlet in Pontiac. All
summer long, Sweet has made the trip from the Belle Isle Aquarium to this small pond looking
for a creature called the Purple Lilliput. These mussels, native to the Great Lakes area, have been
struggling to survive in Michigan, especially since the arrival of Zebra Mussels. Sweet’s made it
his mission to find out if there are any of these Lilliputs in Michigan still alive.


“I was very skeptical and didn’t know if we would find any live ones left because previous
surveyors were beginning to predict that they were gone. No one has found them for several
years.”


Zebra Mussels have been in the Clinton River for six or seven years. Zebras are very competitive
feeders. They strip the food out of the water before the native species can get it. Their presence
in domestic waters has had a catastrophic effect on many species. In fact, because of Zebra
Mussels and other factors like pollution, almost a third of North America’s freshwater mussels are
considered endangered or threatened with extinction.


Doug Sweet says Dawson’s Millpond Outlet is the last place to find Purple Lilliput mussels in
Michigan, and he’s afraid they will die out here, too.


“Looks like mostly all dead Purple Lilliputs. Yup.”


So far, Sweet and his team have found nine live Lilliputs. And that means there are probably
between 100 and 150 of them in that location. Though no one knows how long Purple Lilliputs
live, Sweet says other kinds of lilliput mussels live only about eight years.


“If the Purple Lilliputs are anything similar to that, then we’re running out of time because the
zebra mussels have been here for about six years now. And if they’re not reproducing, if there’s
too much competition, then we might be seeing the very last of the adult live Purple Lilliputs.”


When Sweet moved to the area, zebra mussels were starting to move into the Great Lakes region.
He’s a fish biologist, but he became so concerned about the plight of native mussels, he decided to
find out how they were faring. He contacted other biologists to ask what studies had been done.


Just a few years earlier, Oakland University Biology Professor Doug Hunter started looking for
the Purple Lilliput mussel in several lakes and streams around southeastern Michigan. During his
first few surveys, Hunter found more than 20 Lilliputs, but eventually he gave up hope and
assumed that the small creature was destined to die out in the state.


“Every year we went back after those first couple of fairly successful years, we got fewer and
fewer. The last time I went out there I think I got one or two. And I thought, “Well, this doesn’t
look good at all.” I wrote a report to the Wildlife Division in which I said, “I think this is an
imperiled population that may be on its way to local extinction.”


Doug Sweet picked up the research where Hunter left off and is now focusing his efforts on
trying to save the Purple Lilliput. Sweet says the number of lakes and streams in Michigan where
Zebra Mussels have taken hold is almost doubling every year. He says people should realize that
what they do with their boats affects an entire ecosystem.


“People are responsible for spreading the Zebra mussels all over the place. Everybody who has
Waverunners, boats, fishermen with bait buckets… they have to be conscientious that if they’re
fishing in one lake, you’ve got to clean your boat well before you transfer it to another lake or
stream.”


But even so, it may be too late for the Purple Lilliput. Sweet and his team snorkel through the
murky water, use glass bottom buckets, or dig their fingers into the black sediment, looking for
surviving buried mussels. Eventually, though, the hard work does pay off.


“A live one? Ooh, we think we have another live Purple Lilliput…
There we have it, another live one, ten, so this revises our population estimate right there, because
we found this in a quadrat excavation… This is excellent; it’s exciting. You know, who could say
that you’d get excited over a little critter like that.”


Later the same day, the team finds another live Purple Lilliput, a male, bringing the grand total up
to 11. Sweet hopes he can find a safe haven for the Lilliputs somewhere in southeastern
Michigan where the tiny population can slowly begin to recover. Doug Sweet is now finishing up
his fieldwork, and will soon begin studying his results for a report to the state.


For the Great Lakes Radio Consortium, I’m Celeste Headlee.

CANADIAN ‘SPECIES-AT-RISK’ ACT TOO WEAK?

More than 1,300 U.S. and Canadian scientists are asking the Canadian government to strengthen proposed legislation that would protect endangered species. The Great Lakes Radio Consortium’s Karen Kelly explains:

Transcript

More than 13 hundred U.S. and Canadian scientists are asking the Canadian government to strengthen proposed legislation that would protect endangered species. The Great Lakes Radio Consortium’s Karen Kelly reports.


Right now, endangered species in Canada have no federal protection. The new Species at Risk Act would make it illegal for people to kill the 3 hundred 80 plants and animals considered at risk. But unlike the American law, the proposal does not guarantee that the land or waters in which these animals live will be protected from development. University of Ottawa biology professor David Currie says that’s led to a protest among scientists.


“Virtually all of the studies that have been done on the reasons why species become endangered or go extinct have shown that at least some aspect of habitat loss is involved and in many of the most dramatic cases of extinction, species’ habitats have been simply been entirely wiped out.”


The government’s environment committee will consider amendments to the bill in October. For the Great Lakes Radio Consortium, I’m Karen Kelly.