A study has just been published in PLOS one looking at whether certain angling techniques catch fish with different behavioural traits, or more colloquially, “personalities”. The study angled 100 rock and largemouth bass using two separate techniques, actively fished flashy lipless crankbaits or passively fished artificial worm lures and then tested in the lab whether the fish caught using each method had differing “personalities”.
The study measured the time it took fish to exit a refuge, as well as flight-initiation-distance, latency-to-recapture and with a net, and the general activity level. Only the time it took to exit the refuge, a good indicator of “boldness” was correlated with any of the measured traits. Overall, smaller fish and fish caught on flashy lipless crankbaits exited the refuge earlier than bigger fish or fish caught on worm imitations. The difference in the time it took to exit the refuge between the two angling techniques was most pronounced in large largemouth bass (greater than 30cm), with fish caught on actively fished crankbaits (bolder) exiting the refuge earlier than fish caught on passively fished worms (shy, shrinking violets).
This is a rad result, showing that the way in which us anglers target fish can actually change the fish we are able to catch within a population. There are obviously management implications of such work (discussed in the article), but there are also lessons we can learn as anglers. For example, in highly fished waters (especially where take is significant) or when chasing large fish, natural, finesse techniques are likely to be most successful because the fish we are after are likely to be shy. This may seem obvious and its true that advice on catching big fish or fish in heavily pressured waters is exactly that, being able to actually put some science behind the reasons for that, to know that at least some of that effect might be due to behavioural differences between fish within a population is both useful and in my opinion, really really cool.
Obviously, given that this is really one of the first studies of its kind, some caution needs to be shown when extrapolating the results to other species and systems and a lot more work needs to be done in the area, to really solidify that this result has consistent effects across species and populations, but its still really cool. It also adds some weight to one of my theories about my declining success in the carp hole (which was unwittingly an uncontrolled experiment potentially testing effects like this) and the ridiculous lengths I eventually had to go to to get a take. My experience in the carp hole may have been simply due to removing all of the bold fish (the fish I caught and humanely dispatched) and being left only with a bunch of shy, super cautious, accountant type carp, rather than the fish “learning” (although both effects probably played a role).
Anyway, I highly recommend you go read the whole article “Does angling technique selectively target fishes based on their behavioural type?” (its open access).