((PKG))  SEA LAMPREY  
((Banner:  Saving the Fish)) 
((Reporter/Camera:  Ailin Li))
((Map:  Millersburg, Michigan))  
 
((NATS, MUSIC))  
((Scott Miehls, Fish Biologist, USGS)) 
The most obvious feature of the sea lamprey is the suction 
cup shaped mouth.  We call it the oral disc.  It's just a 
perfectly round mouth.  The sea lamprey mouth is 
completely lined and ringed with teeth, has about 150 teeth 
inside that mouth and that allows them to really latch on and 
hold onto a prey fish.  
((NATS))  
((Scott Miehls, Fish Biologist, USGS)) 
My name is Scott Miehls.  I'm a fish biologist with the U.S. 
Geological Survey stationed here at the Hammond Bay 
Biological Station in northern Michigan.  
((NATS))  
((Scott Miehls, Fish Biologist, USGS))  
The sea lamprey is an ancient jawless fish.  It's a very 
snake-like fish.  A lot of people confuse them with eels 
because they do look very eel-like but they're a completely 
different family.  The sea lamprey are called the vampire of 
the Great Lakes because they attach and drink the blood of 
our native fish species here.  They use their suction cup-
mouth to attach onto the side of the fish.  They're able to 
create a suction force about seven times greater than your 
average household vacuum cleaner.  And then they can also 
rasp into the side of the fish with the teeth that line that 
suction cup mouth.  They'll stay attached to the prey fish as 
long as that prey fish is healthy.  They end up ultimately 
draining so much blood and juice from the fish that they kill 
it.  A single sea lamprey will kill about 40 pounds [18 kg] of 
fish prey in its lifetime which occurs in about an 18-month 
period.  In Lake Huron behind us, there are anywhere from 
80,000 to 150,000 parasitic sea lamprey swimming around 
right now.  
((NATS))  
((Scott Miehls, Fish Biologist, USGS))  
Probably the sea lamprey is one of, if not the most, 
devastating species to have invaded the Great Lakes.  The 
sea lamprey actually swam or hitched a ride into the Great 
Lakes through the canal system.  So, as the canal systems 
were being built to connect the Great Lakes to the East 
Coast to the Atlantic Ocean, from there, it only took a 
decade or two to really completely infest all five of the Great 
Lakes and wipe out the native fish populations. 
((NATS))  
((Scott Miehls, Fish Biologist, USGS))  
Specifically, one of the research projects that we have 
underway is trying to develop a tool where we can 
selectively pass fish.  So, right now, we're actually using one 
of the Whooshh Innovations’ scanning devices and we're 
traveling around to various locations around the Great 
Lakes, working with state management agencies, collecting 
the fish and collecting images of those fish.  Those images 
are then going to be used to develop an algorithm.  We're 
developing fish recognition technology I guess you could 
say. 
((NATS))  
((Nick Johnson, Research Ecologist, USGS))  
Sea Lamprey control has two primary methods.  The first is 
to use barriers and dams to keep adult sea lamprey from 
reaching spawning habitat.  Where larvae are produced, 
there's a lampricide which is a compound that specifically 
kills larval sea lamprey that's applied and removes larval sea 
lamprey from the streams before they metamorphose and go 
out into the lakes and kill fish.  
((NATS))  
((Ed Benzer, U.S. Fish and Wildlife Service)) 
So, here we're sorting according to the male and female.  
So, the females, the way we can tell is, of course, they're full 
of eggs, from 60,000 to 80,000 eggs in there.  And then the 
male is a tighter belly and a dorsal rope on the top.?There's 
a good example of one right there.  
((NATS))  
((Nick Johnson, Research Ecologist, USGS)) 
The work we're researching is whether or not we can reduce 
reproduction.  So, the males come in from the trap sites and 
we make sure that all the males are sorted from the females. 
So, we're only injecting males.  They then get transported 
inside the facility where they're injected with a chemo 
sterilant.  We just kill the female and we release the sterile 
males.  The reason we fin-clip the animals is so we can tell 
they are sterile.  If we catch a lamprey in a trap and it has 
fin-clips, then we release it because it's on our side.  
((NATS))  
((Researcher))  
So, this is the top fin here.  This is the tail fin.  
((NATS))  
((Nick Johnson, Research Ecologist, USGS))  
These animals are our secret agents or double agents.  
They don't know they're sterile.  And when we release them, 
they go out and find the females in these huge river systems.  
It would be extremely hard for people to go out and find 
these animals, but these males are doing all the hard work 
for us and they don't even know it, and they don't need to 
know it.  It's a very humane way for them to finish their life, in 
some ways. 
((NATS))  
((Andrea Miehls, Communications Associate, USGS)) 
There we go.  All right.  That's a bigger one.  Oh, it's so 
slippery.  When sea lamprey first invaded the Great Lakes, 
many people suggested, "Have you considered actually 
fishing for sea lamprey?  Maybe people would be willing to 
eat them."  But unfortunately, that method failed for multiple 
reasons.  People in the Great Lakes region simply didn't 
have the palate for sea lamprey.  Now interestingly, sea 
lamprey are considered a delicacy in other parts of the 
world.  Spain and Portugal, you could find sea lamprey on a 
menu as the high dollar market price item.  So many people 
ask, "Will a sea lamprey attack me while I'm out swimming in 
the Great Lakes or in one of the streams?"  And the answer, 
thankfully, is no.  Sea lamprey can tell the difference 
between warm and cold-blooded organisms.  We are warm-
blooded and the fish that sea lamprey feed on are cold-
blooded.  Most sea lamprey would swim very quickly away if 
they came near a human.  The fishing economy is very 
valuable to the Great Lakes region.  It's the part of our way 
of life within the Great Lakes and that way of life, the Great 
Lakes as we know them, would not be as they are today had 
it not been for sea lamprey control.  
((NATS))