At this time of the year, beetles represent a plentiful food supply for trout. They begin to hatch around October and continue to do so until late January and early February. The brown beetles costelytra zealandica are the first to begin hatching followed by green beetles. The latter is particularly prevalent in the high country.
I remember a warm sunny day at Lake Coleridge in the Canterbury high country. We were eating lunch on a deserted beach next to the boat when my young son threw a handful of gravel into one of the few trees that overhang this lake. As the gravel fell from the tree the small stones were accompanied by a similar number of fat green beetles dislodged in the commotion. These beetles no doubt make up a sizable percentage of the trout’s food supply during late spring and early summer.
The beetles are an excellent fly to use in the Canterbury high country. I have seen enormous beetle hatches at places like Lake Coleridge and Lake Selfe where the air is thick with them. Often they can be seen washed up on the shoreline of a lake on the downwind side over summer. The brown beetles are the first to begin hatching followed by green beetles. I particularly like this fly because it is quick and easy to tie in several different variations.
It is also possible to fish a dry fly beetle on a lake using spinning gear if you use a plastic bubble float to cast out. You squeeze the plastic bubble while holding it under water which allows a little water to enter so providing the casting weight.
Beetles obviously don’t do a lot when stuck in the water’s surface film so the best way to fish them is to cast out to a likely spot and let them sit there. Repeated casting is more likely to scare fish away in a crystal clear lake.
A beetle can also be fished as a wet fly. In this case, a body tied from chenille in the appropriate colour is the way to go.
Various patterns have long been used to imitate beetle hatches such as Coch-y-bondhu and Loves Lure. You can also tie a very good beetle imitation using deer hair. The best modern option is a beetle made with soft foam. These are easy to tie and importantly never become water-logged and so will float all day.
Hook sizes should be between 8 and 14. You want a dry fly hook such as a Mustad 3904A or something close to it.
The first step is to under-bind your hook. Then tie is a length of Raffia. Olive green if it is to be a green beetle or brown if it is to be a brown specimen. Raffia has some shine to it and produces a very life-like result.