A NEW St George Middle Level Science PODCAST… “Natural Resource Stories – People and Places”

We are proud to announce our new podcast series…

“Natural Resource Stories – People and Places”

Stories and learnings highlighting our connections to and appreciations for our community of people and places

Our first episode is “Meadow Brook Preserve and Rainbow Smelt History”

(click here to link to a QR code to listen or go to https://anchor.fm/alison-england)

              (If you would like to read a transcript of our podcast, click here)

This spring, students learned about the special resource history of Meadow Brook Preserve, the newest preserve and trail in our town.

In this episode, local residents Randy Elwell and John Melquist spoke to St. George School students and shared stories about smelting when they were kids; but now, smelt are hard to catch since the St.George River doesn’t freeze anymore, and smelt populations have been in decline since the 1980’s. Join us to listen to the local history of smelt fishing around the peninsula, and smelt history in Meadow Brook Preserve.

We hope to create more episodes about special places and their natural and human history…If you have your own story to tell about a special place, please contact the St. George School.

A Covid Fall and Hurricane Teddy

After school went to remote learning after March 13th, 2020, we are happy to be back to in-person learning at St. George School!

On Monday, September 21, 2020, the remnants of Hurricane Teddy tracked toward Nova Scotia and gave mid-coast Maine a forecast of wind, waves and coastal flooding in low-lying areas.  Unfortunately, because we’ve observed other storm tides, super moon and king tides bring tidal water right into the marsh, we knew we could expect saltwater intrusion into the marsh .  Fortunately, we were able to observe and capture video of the tidal event at our marsh, firsthand.

Later, on Friday, we found dead and dying minnows. We wonder what species they are and even though they may tolerate brackish waters normally found in Ripley Creek, why did quite a few of them die? Was it the 10.0 PPT salinity we measured at that time – both in Ripley Creek and in the marsh in the location of the outlet itself and also behind the parking lot area?

Worm Moon Tide, March 10th 2020

High tide today Tuesday, March 10th, 2020 was at 12:06 PM.  The tide height predicted was 11.6 feet, the highest of the month, coinciding with yesterday’s full and “super” moon at 1:47 PM.  Another super moon will appear on April 8th. These pictures were taken at 12:13 PM.  The drop in height was about a foot in height.  If you look closely on the opposite shore, right at the waterline, there are two bored holes in the rock ledge where iron rod of the old dam structure was fastened into the rock.  The two holes make a good reference for comparison as we less formally observe the tide height.  The speed of the current was astonishing. 

The flow made a huge eddy in the largest (and deepest) “pool” area of the marsh (outlined below).

At the same time the water was rushing into the marsh, the surface waters on the ocean side of Ripley Creek showed very little movement at all.  Keep in mind, the culvert is seven feet in diameter!

Our neighbor in the house bordering Ripley Creek on the marsh side of the road came out to tell us about recent beaver activity.  We saw numerous places along both side of the creek where beaver have been felling or chewing saplings and trees.  She told us they had climbed the bank to the top and taken her forsythia stems.  She thinks they are actively building a lodge in a nearby location and they had sticks and structure across the outlet that has been washed out overnight in the high tides.  We are very interested in documenting the activity of the beavers.

We did measure the salinity with our hand-held probe.  Interestingly, the salinity on the surface continues the pattern of low salinity readings we have observed in the past.  We measured a salinity of 0.94 PPT and 0.52 PPT in the outlet area.  There will be another supermoon high tide of 11.3 on April 9th at 12:40 PM, so stay tuned!!

King Tides

Can you see any structure of the dam to separate what is normally Ripley Creek from the marsh?

High Tide today (October 28th, 2019) was at 12:13 PM.  Dylan measured the salinity of several locations at 12:41 PM.  Here’s what data was collected:

Salinity Measurements:

From the dam/outlet, just inside the marsh:  between 1 and 1.25 ppt.  We wonder if this was because we were measuring at the surface.

From the upstream edge of the culvert in the stream:  10 ppt.

From the edge of of the ocean end of the culvert:  10 ppt.  We wonder why this is so different than at the site of the dam structure, because the outlet was clearly under water.  We actually watched the water flow in to the marsh, then change and flow out of the marsh.

These King Tides were actually predicted for the period of October 26th – 31st, 2019 by NOAA.  From their “High Tide Bulletin” site they explain that these tides are because the moon is at its “new” phase (3% illumination at the time of our observations) and this creates an alignment of the sun and the moon and the Earth with greater gravitational pull in the same plane, and also because the distance between the moon and the Earth, is closer now than at other times in its orbit.  Today, an app we looked at calculated the distance of the moon at 375,019 km (233030.974 miles).

Dylan is interested in how the American Eel, who lives in our marsh and whose elver run is harvested by local elver fishermen may be affected by the brackish waters of our “freshwater marsh”.  We would like to find out more.

Salinity measurement of 10 PPT

Salinity measurement fluctuating between 1-1.25 PPT


Fall Findings

After our paddle, we worked hard to make claims from our spring studies, and summarize our findings as we wrapped up last school year and analyzed our fall salinity data, as well as depth findings.  Here is our presentation that we passed along to the town Conservation Committee.  Of note is our ideas for the future, and our plans to build and deploy more technology to capture data to continue our studies.

Paddling the Marsh

The back-to-school autumn weather was perfect for a paddle on the marsh!  After reflections on our work last year (see below), we wanted to broaden our experience and our ability to access the rest of the water for some additional data collection. Last year, we monitored salinity and we had alewife fry in different salinities to see if they were able to survive.

Since then, our town is requesting the Department of Marine Resources to re-stocking the marsh with alewives.  We wanted to provide depth information to help officials evaluate a re-stocking effort and we wanted to pull the Marsh Monitor probe for recent salinity data.

Our paddle experience also had the goal of thinking about “indicators” of the health of our marsh and how we might approach using technology this year to enhance our studies of the marsh and why alewives are not returning.

Thanks to a generous grant from the Georges River Educational Foundation, we were able to work with Port Clyde Kayak and have a fun paddle throughout the marsh and collect some valuable data in the process.

Our “headline” take-aways were:

The marsh is very shallow throughout!!  (Less than a meter)

Salinity is persistent…we measured 5-8 parts per thousand (ppt) throughout the marsh.

It is apparent that our freshwater marsh habitat is experiencing brackish conditions; not necessarily good news for alewife breeding habitat. Now we turn toward formalizing our findings to pass along to the Conservation Commission to inform and hopefully bolster a plan going forward.

Our reflections of last year…

“My highlight from last year’s science class for me was studying the alewives.  I enjoyed going down to the marsh and being able to have some time to myself down there. I also liked that when we studied that, we were solving a real life problem “Why did the alewives leave?” and “How can we get them to come back?” I think it helps us how to solve real world problems and how we can help our environment.”

“I really enjoyed doing research on the marsh and alewives, like going to the marsh and taking samples and doing experiments with the alewives.”

“I liked going down to the marsh and studying alewives.  It was great besides cutting my toe. I enjoyed it because it was outside and I like being outside where I can be more hands-on.”

“The highlight of our year last year in my opinion was learning about the alewives in our marsh. This is my highlight because I enjoy hands-on work and learning about the alewives allowed us to go down to the marsh and go on field trips outside, and we got to set up the tanks and many other things.”

“I like the outside activities because I focus easier with physical settings.”

“My highlight from 7th grade was the alewife project and measuring the salinity.  It was fun putting out the salinity probe and finding out what the salinity was different days and even after king tides.”

“My most memorable moment in 7th grade was taking the ear bone out of the alewife.”

Our Celebration of Learning!

Our Celebration of Learning on June 13th, 2019 was a rewarding experience!  We had many guests visit our classroom, including representatives from the Natural Resources Council of Maine who supported our project with grant money. Students greeted, guided visitors to numerous stations around the room to see the different facets of our work investigating the salinity effects to alewife reproduction in the marsh.  On display were our aquariums with varying salinities and demonstrations of daily observations, data gathering and feeding methods.

A clever zooplankton viewer was rigged up by Jayden to make it very easy to see the natural food of alewife fry.

How we measure salinity with a refractometer and how we monitor our aquarium salinities with our digital hand-held probe was demonstrated; our data from May as well as graphs and data analysis and claims were on display…Bryson had his Maker Space probe to talk to people about, as well as a display of June’s temperature, salinity and tide height data.

We had a live demonstration of how we identify alewives and their gender as well as otolith removal.  Otoliths are the earbones of fish and can give researchers an amazingly detailed analysis of the age of the fish and the waters in which it has lived.  Scale sampling and aging techniques via our classroom microscope were also on hand.

Our life cycle informational graphic displays were there to see and rounding out our displays were our Nature Notes, soon to be published by the Gulf of Maine Natural Resources Institute and their Vital Signs program.

We’d like to thank our visitors and our community for supporting our learning efforts!

Note:  Here is a link to our published Nature Notes in the middle level science journal “Findings From the Field” (Vol. 2).

Analyzing May Salinity Data

One our big goals this spring was to collect salinity data during the spring tides of May and June.  We met that goal with the deployment of the Maker Space digital salinity probe.  The data card yielded the following analysis, which is promising for the alewives.  

Here are two student claims about our data.

A graph displaying the changes in the height of the tides and the changes in salinity, May 14th – 23rd, 2019

Two small alewife fry, approximately 2 cm in length, swimming against the backdrop of our data sheet!

The Salinity Claims about our Marsh (Ella)

We were able to collect data from our Maker Space probe, here is what we got: 

During the May spring tides there was salt brought into our marsh. Our evidence is the data collected from salinity probe. We made a graph to show what the salinity was day to day from May 8th to May 23rd. On the day of the spring tide, May 18th the salinity shot up from 0.3 PPT to 1.6PPT. On this day the height of the tide was 11.3 feet. 

On our graph we saw that the height of the tide is the independent variable and the salinity is the dependent variable. That means that the salinity depends on the height of the tide. For an example, when the height of the tide is increasing then than the salinity would also be  increasing. For an example on May 17th we had an 11 ft tide and the salinity was 0.3 PPT. Then as the tide increased on May 19th to an 11.3 ft tide with a salinity of 1.3.     

The salinity of the marsh changed quickly, in small amounts. Our evidence is, in the days between May 17th – May 2oth. There was a range of  0.1 PPT over 3 different samples in a 40 minute period. This proves that our salinity probe can measure small amounts of salt at short period of time.  


Salinity Data (Brooke)

The May 2019 spring tides brought salt in to our marsh. We gathered all of our data in the marsh from the salinity probe built in the Maker Space by a classmate. The highest spring tide was 11.3 ft on the 18th with a salinity of 1.6 parts per thousand (ppt). 

There is a positive relationship between the height of the tide and the salinity in the marsh. When the height of the tide gets bigger, the salinity increases. When the height of the tide is decreasing, the salinity decreases. For example, on May 19th the tide was 10.6 ft and the salinity was 1.2 ppt. The next day on the 20th, the height of the tide was 10.4 ft and the salinity was 0.8 ppt.     

The salinity changed by small amounts in short amounts of time. From May 17th-20th, for the first forty minutes of each day the salinity changed by 0.1 ppt.

If we had eggs in our marsh they should be able to survive the 1.6 ppt salinity that was measured in May, based on two professional science studies that found eggs can survive in salinities under 2.0 ppt. We read about these studies before setting up our tanks in our classroom.


Setting Up Our Aquariums for Alewife Eggs!

We are now in LAB mode!  The alewives are spawning in North Pond, where we have a collection permit, and we have some eggs in a bucket (with the cool spring, the eggs have not concentrated in the waters making collection challenging). Now we need to set up our aquariums with the different amounts of salt we have decided for each tank.  Our question is:  Will a salinity greater than 2.0 ppt affect the survival of alewife eggs or fry?  Most classmates think that salinities greater than 2.0 ppt will decrease the survival of eggs and fry.(Substitute student hypothesis here?)  The question and our hypothesis was framed and informed by published results of the few previous salinity studies (a peer review process!) that we found.


We have to figure out how to create salinities of 2 ppt, 4 ppt, 6 ppt, and 8 ppt for the aquariums we’ll compare to our control aquarium.  Salinity is the one variable we are testing.  Our constants will be to use the same size tank, the same water level in the aquariums, the same temperature, and the same number of eggs.  To figure out our salinities, we used our math skills.

Massing a specific gram measurement of “Instant Ocean” salts to add to distilled water to make 6 PPT salinity

We started by putting a gallon of distilled water into a clean (large) aquarium.  We added 1/8 of a teaspoon of “Instant Ocean” salts, which we massed and determined was 1.14 grams, to the gallon of distilled water.  Interestingly, the gallon container was marked 3.78 L (3,780 ml), but we measured its contents and found the gallon to contain 3,880 ml of distilled water.  We mixed the solution thoroughly, then let it sit for about 5 minutes, then measured its salinity.  The salinity was 0.26 PPT.  Both our classes did these steps, and we both measured a salinity of 0.26 PPT.  From here, the rest was math to get a basic salinity “recipe” to make whatever we needed.  We had to use math to solve for how many grams of Instant Ocean would make 1 PPT.  Once we knew this, we could double our amount of Instant Ocean to make 2 PPT, for example.


The tanks are now all set up and ready for eggs!!