Today, Jonathan Travels to a river in Maine to meet an alewife!

Welcome to Jonathan Bird’s Blue World!

It’s spring in New England, and I’m off on an adventure.

I’m driving to Pembroke, Maine to witness an amazing spectacle of nature.

We pull off the road at a river, a beautiful spot that looks like many rivers in Maine.

This is the Pennamaquan.

In the 1950s, the Pennamaquan River was dammed up to create nesting habitat for waterfowl.

So above the dam, it’s a wide, slow-flowing river.

Further up is a Lake.

But just below the dam, the Pennamaquan is quite a bit more turbulent, all the way to

the ocean, about a mile downstream.

Alewives, a kind of herring, are anadromous fish, which means they live in the ocean,

(pause) but they migrate temporarily into fresh water to spawn.

These fish are making their way up the Pennamaquan River all the way to Pennamaquan lake to lay

their eggs.

It’s only 8 miles, but the fish have some challenges.

First, they have to get through all the rapids!

But getting around the dam is only possible because of a series of fish ladders, sometimes

called fishways.

I’m here to meet up with Chris Bartlett, a marine extension Associate from Maine Sea

Grant who is here to make sure that the fish are making it upstream.

Hi Chris!

Hey Jonathan!

How you doing?

Good.

Good to see you.

Good to see you too.

Welcome to the Pennamaquan River!

Wow, it’s really flowing!

It is, yeah we had about an inch of rain so water levels are up.

So do we have some fish in here?

We have lots of fish!

These are alewife.

During the spawning run, Chris, or volunteers from the Downeast Salmon Federation, are here

almost every day to check on the fish.

Get in there!

Perfect.

Fiesty!

They are, aren’t they?

They’re bigger than I expected.

That’s an alewife.

These days, alewives are not widely eaten by people, but they’re an extremely important

part of the food chain, both in the ocean and fresh water.

Alewives are food for everything from seals to cod and even eagles.

But their numbers had been declining for years due to overfishing, pollution, and especially

dams in their spawning waterways.

Something had to be done about it.

In 2014, the Maine Department of Marine Resources tasked Chris with getting a good count of

how many fish were making it up to the lake to spawn.

Soon, he realized that the fishway was in disrepair.

With a little effort, and some volunteer help, the alewife had a clear path up the fishway.

We counted 70,000 fish migrating upstream our first year, did repairs to the fishway

and last year we had over 245,000 fish.

Wow, so they are making a comeback.

They are, and it’s really great to see.

So how do you count 245 thousand fish?

With a clever electronic fish counter placed in a narrow section of the river through which

all the fish must pass.

We are now using this resistive counter, which is an electrical device that counts fish swimming

though a series of PVC pipes, and those pipes have hose clamps in them that are weakly electrified.

And the fish’s own electrical conductance will get counted as it swims through the pipe.

It’s very cool technology.

So you can see by looking in the box, over the last 24 hour period, how many fish have

swum through each pipe.

So what are you getting for numbers?

If you would like to read them off to me I will record them here.

So, number one is 82, number two is 61, number three is 143, number four is 61, number five

is 8.

I guess they don’t like number five.

Number six is 1—they really don’t like number 6.

Number seven is 85, number eight is 3292.

They really like number 8!

I think they do!

Number nine is 1076.

And the whole thing runs on a couple car batteries?

It does.

So how long can it run before you have to swap out or charge it or…

The manufacturer says it can run up to two weeks.

We don’t typically let it run that long.

We just want to ensure that we don’t lose any data, so that’s why we collect it on

a daily basis.

Once I have recorded the information I now just reset the counter and it zeros out.

We start all over again.

How often do you read it?

Once a day.

Every day you’ve got to drive up here and read that?

Well, there’s a few of us that are doing it so…I’m on the weekend shift.

Because of the dam, the success of the entire spawning run depends on the fishways.

So Chris, tell me about this fish ladder.

So this is a Denil style fishway.

So you have a concrete trough that is broken up with these wooden baffles.

And you can’t see the bottom of the baffles but it’s like a picture frame.

And so there’s wood on the bottom as well as on the sides and the wood blocks the current

to give the fish a resting spot.

So even though it looks like the water is moving very quickly, at the bottom there is

very little current because the wood is blocking the current.

So the fish can swim up the fishway one baffle at a time, resting on their way.

And so if you were to put your camera into the bottom of the fishway, you would see fish

calmly resting before they shoot up through the fast water to take another rest.

So that’s how the fishway works.

As much fun as it is to watch fish climb the fishway and go through the fish counter, I’m

betting it will be more fun to hop in the water with the fish.

Just walking down the street with a 50 pound camera housing.

Nothing unusual.

Nothing to see here.

While carrying the camera to the water is awkward, at least I don’t need my scuba

tanks.

I don’t even need a mask!

First a few quick camera adjustments…

…and then I join the fish in the river.

As long as I hold still, the fish get used to me and they treat my camera like just another

rock.

They swim right up to the lens.

With the monitor mounted on top of the camera, I barely even have to get wet.

But that 58° water makes me glad I put on a wetsuit!

It’s weird being right in the middle of so many fish that are not afraid.

It’s not common for me to get so close to a school of fish.

This is amazing!

Eventually I settle down into a deeper spot and relax.

The fish don’t even mind my feet.

They have spawning to do and some guy in a wetsuit isn’t going to stop them.

Due to the efforts of a relatively small number of people who set out to make a difference,

the spawning population of alewife on just one river in Maine has more than tripled in

only 4 years.

It goes to show that sometimes a little effort can make a big difference.

And while sitting in a river in Maine may not seem as exotic as many of my filming expeditions,

I’m constantly amazed by the new things I learn everywhere I go.

Even a small river in downeast Maine can be a fantastic journey into the blue world.