Anglers know them as willow grub, some love them and others hate them, but whatever your feelings about them, they can make fishing very frustrating.
Now that the weather has warmed up, hopefully permanently, it will not be long until these tiny larvae are falling like rain upon the water, bringing even large trout to the surface to feast on them.
There are two factors that make life difficult for the fly fisher, the small size of the larva and the vast number of them. The factors that help the angler are that the trout are feeding at the surface and are easily spotted and they will feed almost non-stop throughout the day.
I find that dropping your fly as close as possible to a feeding fish increases the chances of getting a take, and despite trout’s reputation of being hard to catch when feeding on willow grub, the fly used is not critical most of the time.
I catch a large percentage of my trout feeding on willow grub on a hare’s ear nymph but if they are being fussy, I quickly change to a specific willow grub imitation. It is very simple — just some yellow thread wound along the hook shank, around the bend a little and then back to the eye of the hook. This is on a very light size 16 hook.
If the fish are even fussier, I will try one with two turns of the tiniest hackle I can find on one of my grizzle capes. This stops it sinking to quickly. Typically, the willow grub will drop over the Christmas holidays, so be prepared.
Midweek rain raised river levels a little but they are now dropping back. Trout will be looking for beetles falling on the water so fishing a floating beetle imitation even if there are no rises can bring fish up to the surface. Patterns are not critical as long as they float well so that you can see them on the water.
I fished the lower Taieri the other day and although it is peat-stained it was still possible to spot fish — which is just as well as there were very few rises. If you fish parts of a river regularly, it often pays to fish bling through areas that you have seen or caught fish on previous visits.
My usual tactic is to fish a weighted hare’s ear nymph, casting it square to the current and allowing it to sink for a few seconds or longer if the water is deep. Then raise the rod gently to lift the nymph towards the surface and if there is no response let it sink again two or three times before recasting. This worked nicely for me this week, although not all fish hooked were landed, but it gave a measure of success on a slow day.
