Common Knowledge On Asp Behaviour

Common Knowledge On Asp Behaviour

Bernd Ziesche | Wednesday, 14 August 2019

It's hard to find some detailed proven information about asp behaviour. That is of course because that species of fish other than for us anglers yet isn't discovered to be a pretty interesting one.

Gladly not much people want to eat asp. So there is no market for that!

This leaves me in the situation, that there is little information about asp behaviour available.

For the past weeks I have been studying asp myself. I spent a lot of hours standing on bridges and watching them hunt for baitfish.

Just a week ago I was reading in a German fly fishing magazine, that asp are hunting for baitfish by using their eyes in the very first place. Yet I hardly disagree based on my own studies.

Both in clear and muddy water asp are mostly making the decision weather to run (hammer) into the single baitfish or the school of baitfish from a distance impossible (for asp) to watch thru such a distance. At the same time there is clearly a huge difference in asp behaviour regarding clear vs. muddy water when I am near them. In clear water they see me and usually run off. In muddy water they will be hunting below my rod often! Obviously they see me thru clear water, but don't see me thru muddy water. That tells me, that they can't see any significant distances in muddy water, which also seems quite logical.

Also asp are running into baitfish in such high speed, that I doubt they suddenly switch from using their lateral line organ to a) precisely locate the position, b) precisely identify shape, size + numbers and c) movement of the baitfish into using their eyes to see what's coming close. No, they already know exactly what's coming when they start to run into their bait. I am sure they don't use their eyes to get that information pre running.

I yet don't know how asp do differentiate between their own fry and other baitfish. I think they use their sense of smell here. But yet I have no prove for that. I do know, that they can't make that decision by watching them. That is again because having their own fry and their food next each other I often saw them coming into the bait avoiding their own species from quite distances (impossible to be seen).

I am pretty sure, that asp in the first place use their lateral line organ and their sense of smell to hunt baitfish. Now this doesn't mean that they never add their eyes to get whatever information. All am saying is, that the eyes are not used in the first priority here. You disagree, let me know pls.. ;)

In that fly fishing magazine it was also said to be impossible for fly fishermen to catch asp in none moving water. I agree it to be harder to find out how to catch them here. But they are easily catchable with wobblers and spinners in fast action presented by spinfishermen. Again a serious indication, that they feel the movements! Offering a fly coming in such actions and we ARE in the stillwater game, too.

Then I saw asp running at my flies at high speed but refusing a millisecond before my fly. I think this is based on the wrong smell signature or they were just going to spook my fly out of their territory!

I was really thinking about how to find out this.

My current idea is to freeze a baitfish and then cast the frozen baitfish with my fly rod to the asp. That way I offer the perfect smell and can see, if there will be a difference in asp behaviour compared to my fly coming in a wrong smell signature. That should tell me further details hopefully. Obviously I need to leave "fly fishing only" in order to get those pieces of the asp-puzzle!

If you have any links or contacts where to get further detailed information about asp behaviour, I really would appreciate, if you share them!

Of course, if you have made different experiences on asp behaviour, pls. share them with me!

Right now am on my way into further asp fishing!

Great fly fishing week to all of you!

All my best


Few pictures as always... 

asp flyfishing germany