Another chapter in The Road to Environmental Armageddon, my current work in progress. Still hoping (perhaps vainly) for responses from readers.
The Souring Seas
Porters Lake, NS, Thursday, June 4, 2020
At nine, Tony backed the oceanography department’s Boston Whaler to the water’s edge at the Porters Lake Provincial Park boat launch. He untied the boat and passed the painter to Rosie. “You’ve got the boat. I want it launched and us underway before the wind picks up.”
Back in the van, he gingerly backed the trailer into the lake. “Tell me when she floats off the rollers.”
Rosie pulled on the painter. “Now! It’s running away.”
“Pull it to the beach and hang tough. I’ll park the van and we’ll be off.”
A brown pickup roared up after Tony backed their rig off the access road. The pickup screeched to a halt blocking his way. A burly man hopped out. “You from the dee eff oh?” he demanded using the local vernacular for the federal fisheries department.
Tony pointed to their van’s black and yellow Dalhousie University logo. “Dal. Sampling for an oceanography department project. Doesn’t involve the feds.”
“Well, they should investigate our fish kill. Wouldn’t surprise me if those buggers sloughed the job off on someone else.”
“Sorry, not us. Your fish kill a problem related to this spring’s high runoff?”
“How the hell should I know! Dead fish and more lake weed than usual. We called the bloody experts, but they haven’t shown their chicken-shit faces.”
“Problem here, or the inner lake?”
“Inner part mostly, but they’d launch their bloody boat here.”
Tony shrugged his shoulders as he nodded toward Rosie and their whaler. “I must return to our boat. Long day ahead, and we’re not sampling the inner lake.”
The man stood glowering with feet apart and his hands on his hips as Tony side-stepped him and strode toward the whaler.
“What’s happening?” Rosie asked.
Tony hopped aboard and clambered to the stern. “Later. Keep the stern pointing out while I start the motor. Then jump aboard and we’ll get going.”
“So, what’s with Mr. Grumpy?” Rosie asked as Tony swung the whaler toward the inner part of the long narrow lake.
Tony explained as they roared inland under two small bridges to the community of Porters Lake.
Rosie responded as Tony slowed in the passage joining the inner and outer lakes.
“Is the high runoff important, changing environmental conditions in favour of the diatom that bloomed in Jacinta’s experiment?”
Tony stopped where the lake widened to five hundred metres and Rosie dropped their anchor. “Possible, and if it is, this sampling trip may tell the tale. Here’s the plan. One station where it should be freshwater, so not supportive of marine plankton. Then downstream sampling more frequently as we encounter water that’s fresh on top but saltier underneath.”
“Okay, and I see you have the department’s inshore CTD. We can measure temperature salinity and fluorescence with depth, and a water sampler for nutrients, chlorophyll and species identification—”
“Oxygen too, because we may encounter anoxia.”
Rosie nodded, then pointed at a torpedo shaped device. “What’s that?”
“Bathythermograph, it gives us changes in temperature with depth.”
“But the CTD does that.”
“Not until we download the data in the lab. The BT gives us an immediate record we can use to choose the water sample depths.”
“And you want to sample the boundary between salt and fresh water—the boundary between warm and cold.”
“Correct. A surface sample, one at the boundary and one at depth. Shall we start?”
“What’s first. Your BT? You must show me.”
“First, you check the depth on the whaler’s depth sounder. Then, you lower it counting off the knots on its rope, they’re spaced one metre apart, until you get to the bottom. Then you pull it up.”
Rosie picked the BT from its cradle. “Wow, it’s heavy.”
“Solid brass. It must be heavy to drop quickly and straight down.”
She held the torpedo dangling over the side from the lanyard attached to its tail fins. “How fast?”
“Hand over hand, don’t hurry. And count the knots. It’s only twenty metres.”
“Okay here goes.” She lowered the probe from one knot to the next mouthing the numbers until she arrived at twenty. “What now?”
“Haul it back onboard.”
Rosie looked up after setting the BT in its cradle. Tony handed her a small device. “Unclip the microscope slide and place it in this reader. What do you see?”
Rosie squinted into a microscope-like eyepiece. “A trace of temperature versus depth. It’s seven degrees at the surface, stays constant for two metres then between two and five it drops to three, and almost constant to the bottom.”
She turned over the device and checked the slide. “Gold?”
He nodded. “The university’s electron microscope facility plates them with gold. In the BT, a stylus scratches a trace in the gold plating.”
“Neat, but such an old-fashioned museum piece.”
“It tells us what we need when we need it.”
“I get it. We take water samples at one metre, three or four metres, and what, ten metres. We use your torpedo to decide on sampling depths, but later the CTD gives us the actual data.”
“Exactly. Start collecting the water samples. I’ll give you a hand after I deploy the CTD. When we’re done, we go to the next station.”
Six hours later, they’d collected samples from ten stations and were approaching the Provincial Park. A pickup truck with its engine running blocked access to the boat ramp.
“Not Mr. Grumpy’s truck.” Rosie said.
The truck driver sauntered to the foreshore and helped Rosie pull the whaler onto the sand as Tony killed the motor. He waited until Tony joined them near the bow. “Good weather for boating. Hope your sampling was successful?”
Tony hesitated, unsure how to interpret this new friendlier approach. “Foggy morning, but the afternoon was good.”
“And your sampling?”
“Won’t know until we process the samples.”
The stranger sighed. “I know you two can’t make any promises. I represent Porters Lake Environmental Stewardship, and we’d appreciate access to any data you collect. Here’s my card. If you’d give it to whoever’s in charge and ask him to contact me.” He looked back at his vehicle. “I’ll move my truck and let you get on. Unless, you’d like a hand?”
Tony inspected his card. “We’re good. I don’t see how our data will help in a fish kill fight, but I’ll see Professor Krueger gets your card.”
“Why didn’t you mention the hydrogen sulphide at the first station?” Rosie asked as they headed to Halifax.
“Because we shouldn’t comment on what’s normal or abnormal from one measurement.”
“Earlier, you said hydrogen sulphide could have killed the fish.”
“But we can’t say it did.”
“I don’t understand. You want to avoid this environmental issue, but you’re ready to fight about climate change.”
“Because we’re developing a solid knowledge base for anything we say about climate. If we commented on the fish kill, we’d be guessing.”
The analysis of their Porters Lake samples continued into the following week. They found no evidence for the mysterious diatom species responsible for the unusual results in the large aquarium. The source of their prolifically growing diatom remained a mystery.
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