Meet Wilbert Knol

Meet Wilbert Knol

What is your job title?

I am a science technician in the Fisheries Acoustics group at NIWA, based in Wellington

What do you study and why is it important?

Our group is involved in estimating sizes of fish stocks. We use underwater sound, often in combination with other techniques.. Species surveyed are hoki, orange roughy, whiting, oreo and, occasionally, lake trout. Our work helps to keep fishing at levels that can be sustained. This is important for the environment and the economy of New Zealand

What will you be doing on the Graveyard voyage?

On the Seamounts Voyage, I am looking after the scientific echo sounders.

The main scientific sounders are based on the vessel and operate at 12 and 38 kHz, sending a burst of sound from he ship towards the bottom. The resulting echos are picked up by the sounders and used to produce echo-grams: vertical profiles of the water-column and sea floor.

In addition, I have brought along a deep-towed echo sounder which we are going to dangle under the ship, approximately 50 meters above the sea floor. The deep-towed sounder will give a better, close-up view of the sea floor than the ship-mounted sounders.

Another piece of equipment that I am looking after is a small transponder called 'HPR'. We bolt it to our underwater camera frame, or to the deep-towed echo-sounder. It is queried by the vessel, again using underwater sound. The transponder reply tells us how deep and how far away the transponder is, relative to the vessel. As a result, we know the position of the underwater equipment, which is often hundreds of meters away from the ship, depending on wind and currents.

Where were you educated?

I grew up and went to school in the Netherlands, where I also studied electrical and electronic engineering.

How did you become interested in the ocean?

I became interested in ocean things when I moved to New Zealand in 1988 and started working for the Fisheries Research Division of MAF, where I joined a small team that used underwater video cameras and stereo photography to study hoki.

Do you get seasick?

Yes, I get seasick at the start of every voyage, even after years of going to sea. The best way to avoid it: don't go to sea! I don't take pills and I prefer long, four-week voyages with a couple of days steaming at the start, to give me a chance to find my sea legs.

What do you enjoy about your work?

In general: variation (a combination of office, workshop and field work). The people I work with are top-notch. Thirdly, the public-good aspect of our work.

What are some of the challenges that you face?

In general: challenges: equipment failure, computing problems (worth a separate mention), red tape and paperwork.

What have you learned/discovered? What do you hope to learn?

So far, on this trip, we have found that the equipment is by and large working as expected. At this early stage, we are collecting data, which is often monotonous and routine, in particular for non-visual data such as bottom echo soundings.

The discovery comes afterwards as data is analysed and tied together.

I'll be pretty happy if I can complete my tasks, our equipment keeps working as planned and we return home with a good set of data.

How do you spend your spare time?

On this trip? Lots of reading, a bit of socialising. We are working 12 hrs on, 12 off so there isn't that much leisure time.