This article was first published in The Montreal Gazette.

I have long been accustomed to students coming to my office to ask questions. Recently, though, the traffic has increased not because they have more questions, but because word has gotten around about my ducks. They are now coming to visit the 350 or so ducks that share my office.

There are wooden ducks, metal ducks, ceramic ducks, glass ducks, vintage celluloid ducks, ducks stuffed with various fibres, a Lego duck, a puppet duck, ducks made of real rubber and of course the ubiquitous polyvinyl chloride (PVC) ducks.

This all started years ago when I was giving a talk on quackery and was asked how it was that the fraudulent or unproven practices I was talking about were associated with ducks. Well, I had never thought about that. Research was obviously in order.

It turns out that the term does not derive from the sound a duck makes, but from a now-obsolete Dutch expression meaning “to boast” or “prattle,” dating back to the 16th century. That was a time when street vendors boasted about the miraculous salves they were hawking with claims of curing any and all ailments. These con artists came to be known as “quacksalvers.” By the 17th century, the term had wormed itself into the English language and had been shortened to “quack.” It was used to describe charlatan doctors and boisterous sellers of nonsensical nostrum.

Sometime in the late 19th century, cartoonists connected the notion of describing charlatans as “quacks” with the sound of a duck and images depicting medical swindlers as ducks became a common satiric visual pun.

The next time I gave a talk on quackery, I related this story and for emphasis I tossed a little yellow plastic duck that I had kidnapped from my kids’ toy chest into the air. After that talk I remember wondering if there might actually be a “quack doctor” toy duck. This was years before every major city had a duck store, but eBay already existed. I gave that a try. There were ducks, but they were mostly vintage toys with no “quack doctor” duck in sight. However, I did find a “mad scientist” duck. That would have to do, I thought, although I had always objected to the image of a mad scientist. I bought the duck and next time I gave a talk on quackery, I weaved in the story of my new duck.

A few days later, I received a little package in the mail containing a rubber duck with a note explaining that while it was not a doctor duck, it had been in the family a long time and I may find it interesting. And so it began. I looked for ducks at garage sales, flea markets, in toy and antique stores. People started to give me ducks as gifts, and I purchased ducks when I travelled. That’s how an array of ducks of all sizes came to occupy my office shelves. But besides attracting onlookers, they serve a purpose: a constant reminder of the need to fight quackery.

My duck collecting has since spilled into bookends, umbrellas, walking sticks, toys, coffee mugs, bathing suits, T-shirts, shower curtains, socks and even magic tricks: I have a wooden duck that will pick a chosen card out of a deck. As a result of what some might call an obsession, I have also become interested in any science that deals with ducks, even if the connection seems to be somewhat obtuse.

And that is how “duckweed,” a floating freshwater aquatic plant that can be mistaken for algae has entered the picture.

Why is this plant, which can cover a pond, lake or river with what looks like a green blanket, called “duckweed?” Because it grows in waters where ducks regularly swim and where they find the tasty meal “lemna minor,” as the most common species is known. It seems we may be destined to follow in the ducks’ wake. Duckweed is one of the fastest-growing plants on Earth and can, under ideal conditions, double in mass every couple of days. But its most attractive feature is its high protein content, up to 43 per cent in its dry form.

It is estimated that due to population growth, food production by 2050 will have to increase some 60%. That is a challenge, given that agricultural land is limited, climate change can decimate crop yields, and meat production is detrimental to the environment. That’s why scientists are turning to duckweed. Sometimes called “water lentil,” it has long been consumed in Southeast Asia and now a number of companies are looking to grow it under controlled conditions and introduce it into the marketplace. They are not oblivious of the current consumer appetite for protein and the potential boost in profits afforded by a “high protein” claim.

Duckweed doesn’t require farmland, no forests have to be cut down for its cultivation and it can grow in most any climate, yielding 10 times more protein per surface area than soy. It also has an excellent nutritional profile. In addition to protein, it contains fibre, vitamins, various phenolics and is low in fat.

That, along with the plant’s rapid growth, has captured the attention of NASA. Duckweed is being explored as a possible source of food for astronauts on a Mars mission. There are many problems with a prospective Mars journey, ranging from exposure to cosmic rays to social issues associated with confinement, to supplying energy and provisions. Taking food along for a trip that can last more than three years is hardly viable. Conceivably, duckweed can be continuously grown on the spacecraft and serve as fresh, nutritious food.

Plant growth requires light, water, carbon dioxide and a source of nitrogen. Carbon dioxide exhaled by the astronauts can be passed through filters equipped with amines that capture the gas and be released as needed into a chamber where duckweed is grown in water that contains nitrogen compounds extracted from the astronauts’ urine.

While a Mars mission is not imminent, the use of duckweed to produce oil suitable for use as biofuel may be closer to fruition. Duckweed does not produce much oil, but it can be goaded into doing so by applying biotechnology. It is possible to isolate the genes from such high-oil plants as sunflower, soybean or palm that code for oil production and insert these into the genome of duckweed, which will then crank out oil.

Maybe in the future we will be eating duckweed salad and pumping biodiesel fuel into our vehicles.

I have also learned that the tiny duckweed leaves cling to duck feathers so that the ducks sometimes emerge from ponds covered with little green specks. If only I could find a rubber duck covered in duckweed flecks for my collection. That would be just ducky! Which now brings up the question of where that expression comes from. I’ll duck that one.

@‌JoeSchwarcz