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On-board electronics have become almost ubiquitous on pleasure craft. Manufacturers are constantly innovating and developing new technologies, pushing back the limits of detection capabilities.
In this quiz-like article, try your hand at analyzing the images below. For each capture, analyze what you see on the screen, taking into account the clues I'm about to give you (seasonality, location, etc.). Based on this, you'll be able to identify the type of fish behind these screenshots. The answer will be given at the end of the article.
The equipment used
All these captures are from Lowrance HDS Pro or HDS Carbon fishfinders. These are the brand's top-of-the-range series.
In all cases, the associated probe is identical, depending on the configuration used: either an Airmar B75H, particularly appreciated for its high-frequency 2D reading quality, or a Lowrance Active Imaging 3-in-1 probe, enabling SideScan and DownScan functions to be used in addition to the classic sounder view.
Capture 1
Capture 2
Capture 3
Capture 4
Capture 5
Capture 6
Capture response and analysis
Capture 1:
It's bluefin tuna, with a very dense school, the kind of school capable of provoking intense hunts. The season, as well as the fishing area, are two precious clues. Here, the tuna are very compact, just a few meters below the surface.
Capture 2:
On the capture, we can see the presence of an upwelling on the bottom. This is a North Cotentin wreck. These areas are often deep. At slack water, yellows emerge to feed. This is when their fishing is most effective.
A detection on a rock head, in an area with strong currents, initially suggests sea bass. However, the size of the echoes is too small to correspond to sea bass. In reality, it's a school of horse mackerel.
Capture 6:
On a sandbar like this, with a fairly shallow drift, it could have been sea bass. But the echoes aren't scattered enough to indicate hunting sea bass.
In reality, it's a shoal of small yellow dolphins that take advantage of slack tide to climb into the water and hunt.
