With the recent flooding tide of Friday, March 2^nd observed by middle level students, (11.4 foot tide and ‘Nor Easter winds)  Ms. Palmer sampled the marsh on Sunday (10.9 foot tide), using a salinity refractometer.  Here is the discussion the class had that next day, captured by Lydia Myers, when Ms. Palmer came to our classroom to share her data.

The Marsh’s Salinity

Contributed by Lydia Myers 

We had a group discussion with Mrs. England, and Mrs. Palmer about the salinity in the marsh. On Friday March 2nd, Mrs. Palmer walked alongside the marsh and tested the salinity in five different places.

What she discovered was, that close to the culvert where the ocean water comes into the marsh, the salinity there was 25 ppt (part per thousand). I thought this was interesting because the ocean water is rushing into the marsh at a considerably steady pace, when the tide comes in, so I thought that there might have been a higher ppt, as the ocean’s is 33 ppt. She explained how she continued to walk along the marsh’s bank and test the salinity of the water every so often. Mrs. Palmer recorded four other times, the numbers that were seen in order were, (25) 15, 6, 9, and 10 ppt.

As she was telling us what the numbers were and where they were recorded I was surprised when it went from six to nine. At first when she said six I thought the other two spots must have had a really low ppt, but I was amazed that it was just the opposite.

This could be a possible problem for the alewive population, as they come in with the tide to breed in the freshwater marsh around the time of May and June, though it is a possibility that the salinity could decrease from now to then.

Before 2016, no one had seen any alewives in the marsh in over 30 years. Efforts were made from 2009 to 2013 to bring back the alewive population by restocking the marsh with 500 alewives in the spring of each of those four years. Finally the town’s efforts had paid off when, of all people, Mrs. England and some of her now former students, observed three small alewives in a very small amount of water collected in the culvert during a low tide! Though the number of fish had been few, it was a huge accomplishment. Soon after they had observed even more of the fish, at one point in time they even netted approximately ten fish and brought them into the marsh. To this day the alewives have been witnessed swimming back into their birth place (the marsh).

Mrs. England had mentioned the state may possibly be restocking the marsh again this, or next year. We have some concerns about the spawning of the restocked fish, because of the amount of salt in the marsh, as the alewives need a salinity if 0-5ppt  to successfully repopulate. One of our main concerns is if the amount of salt in the marsh will damage the fish eggs.

Now that we have this information about the salinity in the marsh, I wonder if this has anything to do with the alewife problem, and how/why that much salt water is so far back in the marsh.

Contributed by Addie McPhail

March 2nd, 2018

On Friday, March 2nd, my class which was accompanied by Mrs. England, headed down to the culvert between our lunch and recess period. We had recently been informed by Mrs. England to bring boots due to our observation of the high tide that day.  

When we arrived at our destination, we found to our surprise that the tide was 11.4 feet tall, which was one of the highest tides that this month. The water was about an inch from reaching the very top of the culvert. All of my classmates, as well as me, were quite surprised but very interested in why the tide was so high. We learned that because of the full moon (which had occurred the previous night), and the fact that we had a ‘Nor’easter along the coast, that would lead us to have onshore winds. These winds drive the coastal waters to be higher than normal.

Although our class was not there to experience the tide’s arrival which occured at 10:56 am, we were very much surprised and excited to observe the culvert while the tide was in action. (standing on it… ) And even though many pictures were taken for those who weren’t there, I was very glad to be able to see and experience the high tide in person.

 

Shortly after our observations of the high tide near the culvert, Mrs. England invited Mrs. Palmer, another member of staff at our school, to talk to us about an interesting and quite surprising observation she made not long after the high tide. Her observation was measured by her small EC meter.

An EC meter or electrical conductivity meter, measures the salinity or how much salt is in something. All you have to do is carefully place a few drops of the liquid that you are testing underneath the lid. Next, you gently close the lid, and peer into the other end while directing it to some kind of light. There, while you are looking into it, should appear the numbers that represent the salinity of that liquid.

Mrs. Palmer used her trusty EC meter to measure the salinity of the marsh. She got a surprisingly high result in her salinity measure shortly after. These measurements included 25 ppt (parts per thousand) down by the culvert on the upstream side, and even a measure of 10 ppt way up within the marsh. My classmates and I were quite surprised considering that we knew the marsh typically consisted of fresh water.

After Mrs. Palmer finished sharing her latest observation, Mrs. England brought up the alewives, questioning how they would do within the marsh, now that there was a higher ppt. That got us all to thinking about what would be in store for us in the spring. We were all wondering the same question: Will we be able to restock the marsh with alewives this coming spring? 

Right now, we are unsure if we will restock alewives in the marsh this spring or not, but we do hope that the high ppt was just affected by the high tide which recently occurred. We know that if the salt does remain, it will be a risk to deal with if we decide to put more alewives in the marsh. We all hope for the best and wish luck to the marsh until spring. It may be a bumpy ride ahead for alewives, but luckily the Seventh Grade is looking forward to this spring, and hopes that all will be well.