Deep-sea pioneer looks back on a career chasing light in the deep, dark ocean

As a pioneer in the field of bioluminescence, Edie Widder has spent her decades-long career trying to understand the brilliant displays of light that animals display down in the deep. Along the way, she's spent thousands of hours below the ocean's surface, and captured countless scientific wonders on her state-of-the-art camera systems. 

She spoke with Quirks & Quarks host Bob McDonald about her new book, called Below the Edge of Darkness: A Memoir of Exploring Light and Life in the Deep Sea.

This interview has been edited for length and clarity

I think most of us imagine that the deep sea is just never ending darkness, but clearly, according to your book, that's not the case. Can you give me a sense of what it's really like down there?

Yeah, you're right. A lot of people describe it as a world of eternal darkness, but it's anything but, because there are so many animals down there that make light. My very first deep dive was in the Santa Barbara channel in a diving suit. It was an evening dive and I went down to eight hundred feet and I turned out the lights because I knew I would see bioluminescence. I was just completely unprepared for the abundance, the brightness, the beauty. It was overwhelming. It was like Van Gogh's starry night.

Tell me about bioluminescence. What do animals use it for in the deep ocean?

They use it for all the basic things they need to survive. They use it for finding food, for attracting mates and for defence against predators. So finding food, a lot of them have built-in flashlights to help them see in the dark. Some with very elaborate optics to shine the beam outward. They have glowing lures to attract the food to them. And then, oh my goodness, the number of ways they use it for defence is just mind boggling. One way that a lot of animals do it is they actually squirt their luminescent chemicals out into the face of an attacking predator, temporarily blinding it so they can get away into the darkness.

How do these creatures actually make this light?

They produce chemicals, and it's kind of like the light chemicals in a light stick. You break the glass vial and you allow chemicals to mix together and they produce light. It's cold light. There's no heat associated with it. Only these are chemicals that the animals synthesize themselves. So there's an enzyme that's called luciferase and a substrate called luciferin. But those are just generic terms because there's actually different chemicals in different animals. It's evolved many different times in evolutionary history, which is a clear indication of how important it is to survival.

You've worked with quite a bit of technology throughout your career to reach the ocean floor in the depths. How has that field changed since you first started?

The biggest change has been in the sensitivity of the cameras that are being used now. When I first went down, there were no cameras that were as sensitive as the fully dark-adapted human eye. And for a long time, the cameras that I was using were black and white, and we would just have to colourize the image to kind of give an impression of what the luminescence looked like. 

But now there are just these astonishing cameras with ISO levels of a million. I mean, it's incredible. And they're as good, if not in some cases, better than the fully dark-adapted human eye. And so now we can finally share with the world what this amazing light show actually looks like.

You mentioned in the book that it's very difficult to observe life in the deep ocean without disturbing it. Tell me about some of the technology that you've helped to develop that's made it easier to observe the life without stirring it up.

I wanted to develop a camera system that was battery powered that I could leave on the bottom. That wasn't any novel idea. Lots of people were doing that, but I wanted it to be unobtrusive. So that meant that I wanted to use red light that was invisible to the animals. And then I wanted to attract more than just scavengers by putting down bait, which is how it's usually done. I wanted to see active predators. And so I developed this thing, we called the electronic jellyfish, that imitated certain bioluminescent displays that I thought might be attractive to large predators.

How did you know what to say to get a reaction from them?

There is this common deep-sea jellyfish called atolla that produces this pinwheel of light that's absolutely spectacular. And you've got to ask yourself why, given that this is an animal that doesn't have eyes, so it's directed at somebody else. And the hypothesis was that it's what's known as a bioluminescent burglar alarm. This display is like a scream for help with light that lights up whatever's attacking the jellyfish, and hopefully that will be more tempting to a bigger predator that will come and attack the attacker and afford the jellyfish an opportunity for escape. And I wanted to see if that was true. So I wanted to imitate that display and see if it brought in large predators. And boy, did it ever.

What did you see?

The first time I got to test the system was in 2004 in the Gulf of Mexico, and I put the Eye in the Sea down in an oasis on the bottom of the ocean where I thought large predators might patrol. And for the first four hours of the deployment, I started recording with just the red light and no e-jelly on because I wanted to see if I was really observing the animals without disturbing them. And I could tell I really was, they would swim straight toward the light and just basically ignore it. So I had a window into the deep sea and I was ecstatic. 

And then four hours into their deployment, I had programmed the e-jelly to come on for the very first time with that pinwheel display, and 86 seconds after it came on for the very first time, we recorded a squid attacking the e-jelly that was over six feet long and so new to science it couldn't even be placed in any known scientific family. I could not have asked for a better proof of concept.

How is it that we know so little about the deep ocean? 

The biggest problem is chronic underfunding. It's just never been funded. The way space exploration was funded, there was a political driver for space exploration because of the desire to beat the Soviets into space. We've never had that for the ocean, and so it's always been just a tiny fraction of space exploration. For what it costs to launch the Space Shuttle fully loaded, which is about a billion dollars, you could have dove the Johnson Sea-Link submersibles, which I used throughout my career, two dives a day, four hour dives, for 110 years. It's just incredible how little we put into ocean exploration. And yet when we're talking about the ocean, we're talking about the life support machinery for our planet.

So what takeaway message are you hoping that people will get from your book?

I want them to get super excited about this amazing planet that we live on and these amazing discoveries yet to be made in our oceans. Bioluminescence alone has great potential for new discoveries. We've isolated some of the chemicals from these animals, and they have made a huge difference in biomedical research, huge discoveries in cell biology and a Nobel Prize was awarded for it.

There are many other chemicals yet to be discovered and not just bioluminescent chemicals, but other bioactive compounds that could be curing diseases. So we need to tap into that instinct for exploration and use it to our advantage to help further our knowledge of our basic life support systems.

Produced and written by Amanda Buckiewicz