Lake Ontario Shipboard Science: Day 3

July 11, 2018

“Water, water everywhere, yet not a drop to…swim in!”


Our day started very early today, 1:00 am; sampling station ON 41. Being on deck, in pitch-black skies, was reminiscent of the show “Deadliest Catch” where crews worked through the night retrieving their crab pots. Our night, was much less risker. For this station we sampled plankton, water chemistry and sediment.  For the plankton samples, three different nets were used. For vertical water column sampling, circular nets of various mesh sizes. A “Tucker Trawl” was used to collect plankton horizontally from a specific depth. A perfect example of using data to guide your actions, the depth for the Tucker Trawl was determined from the water chemistry tests.  A Rosette sampler, which is an array of Niskin bottles, collected water samples as well as other water quality parameters including a measure of photosynthetic pigments from specific depths. This data was then used to determine at which depth to use the trawl so that the greatest amount of phytoplankton (photosynthetic algae and bacteria) could be collected. Watching the data being collected in real time, as the Rosette sampler descended, was fascinating to observe.  Sediment sampling was collected from a PONAR (think of the “Claw Game”) and a “spider” sediment corer.  What was intriguing is the amount of specialized equipment. There were very few exceptions where a piece of equipment had multiple functions. For example, to extract the sediment cores collected by the “spider”, there was a specialized pump system to extract the cores from their plastic tubes. It was also relieving to see other pieces of equipment were made from a trip to a local hardware store (i.e. small submersible pump with garden hose, PVC sampling pole).

Something else that was quickly apparent was the amount of communication between the marine techs and the pilothouse. At no point, was there any doubt of who was on the fantail (lowest portion of the ship located at the rear of the vessel), what equipment was going in to the water, where it was being deployed and to what depth was it being lowered. Even taking a relatively simple 1 m sample, required clearance from both the captain and a marine tech. We believe that this is one of the many great examples to take home for our students.

Deploying the larger of the two vertical plankton nets.


Tucker Trawl being deployed. Note that the “mouth” of the trawl is currently closed. It will be opened and closed at depth by sending down a “messenger” (small weight to trigger the releases)


“The Spider” sediment corer, a marvelous piece of engineering. Science and engineering practices at its finest!

A real “Ah Ha moment” occurred when patterns started to form between chlorophyll spikes and the thermocline.  Last night after our invigorating presentation by Dr. Greg Boyer, who is collecting samples to better understand the Harmful Algae Blooms, we discovered the “pattern” together the location of the thermocline, increased chlorophyll levels and why we were collecting the various samples at various depths.  These variables along with nutrient studies are thus being used to assess what may contribute to algal blooms.  We hope to take this idea of patterns back to our classroom to show students how research is looking at phenomenon, finding patterns in data, and then making a claim.

We hope to take home how valuable it is to have “GRIT”.  There have been times when it was hot, or an apparatus failed at 11:00pm and the easiest solution would be to just stop.  But we quickly realized that even though we were tired, and uncomfortable we must finish the job to be part of the team.  If we did not get the apparatus repaired, then the group starting at 1:00 am could not obtain the sample and the graduate student would not have his sample he needed for research.  As we were repairing the PFAS device, it took everyone in the group to add ideas and solutions on how to repair the apparatus using our limited resources.   We needed to complete taking all the samples at all the locations methodically and with precision even though the heat index kept increasing in order so we could keep swimming when we returned home.

As we begin our group presentations, we are experiencing some of the research beginnings that our students will experience.  Where do we start, what data do we have, what data do we need, and “What is the Question?”  We hope to simulate this experience by bringing home this data, or collecting similar data of our local water systems. We can share how it is taking GRIT and a team effort to accomplish the final claim.

When we return home we hope to swim in this beautiful environment that we have been experiencing.  Though the weather is hot and beautiful, it puts into perspective how our work this week will help maintain or improve our Great Lakes so we can continue to swim.


Filtering out plankton two samples.

“I am Paddle-to-the sea, from Nipigon Country north of Lake Superior…Please help me find more adventures… Return me to the water in good place to continue voyage…”

– “Paddle-to-the-Sea” by Holling Clancy Holling


The story of a small wooden figure in a canoe carved by a young Native American resonated during the first three days of this cruise


By: Benita Cataldo and Todd Shuskey