Flyboards

Ever since river keepers have been employed by fishing clubs, the desire to improve the fly life on a river has been in evidence. One on the best known keepers of all time, William Lunn used them on the River Test in an attempt to spread the the fly more evenly across the river where fly was sparce on certain beats.

Today ,there is increasing concern about the dissapearance of small river fly, so any help to aid egg laying spinners in their duties, would seem a logical thing to attempt.

Many clubs now use flyboards trying to address this problem, but could there be a better option than just having a floating plank in the river? In an attempt to find out, I have been experimenting with various designs of boards to see if any were actually preferred by various species of fly.

My aim was not only to see what style of board was preferable but also if different types of material had more appeal than others and have found a few surprises along the way. The conventional board was a plank (often one discarded by builders) pointed at one end and two to three feet long. This is either moored to a stake in the river or attached to a bridge or overhead support.

Another popular option is a paving slab placed at 45 degrees in the river. Although not regarded as a board, the desired effect is the same. This option has several disadvantages however, including difficulty in moving and working with, but mainly with our changing climate and general lack of rainfall in the summer months, the now regular falling of water levels leaving any eggs layed on the upper part of the slab earlier, now high and dry, out of water, and with obvious disaterous results.

Materials

Hardwood has often been used when available, for its durability, but is this necessarily the first choice for egg laying flies ? I have constructed boards made of combined hard and softwood to see if more eggs were deposited on either part of the board. Being a combined board, the siteing was less important as using two seperate boards however close, as this may have influenced the fly before even alighting on the board.

Boards were made of several composite materials including very smooth softwood, laminates and brick tiles ( bridge walls are well known egg laying sites ,with the female spinner creeping down the wall and then continuing under water to perform her duties ) but of necessity bridges are in one fixed place and not always where a keeper would have chosen them.

After a few Days in the River

Could a similar material on a moveable board have the same desired effect. Stout plywood, easy to obtain and work with, but not chosen for fly boards, as it seems to be unliked by most fly,( probably because of the glues used in its construction )——- However, while experimenting with a different structure using this material , I was very surprised to find it covered in sedge pupae (agapetus , fuscipes/ ochripes/ delicatulus, the micro sedge) with no space to spare on its surface. Maybe they are not bothered by the glue and I am now designing a new type of caddis board with this material.

Its bottom edge must rest on the floor of the river allowing caddis access, as per conventional paving slab ,but its top never leaving the water to protect the larvae from drying out. As we seem to be relying on sedge fly more than ever before due to the dissapearing ephemeroptera, there may be more necessity in the caddis board than ever before and I have hopes for its introduction this season.

Design

Floating boards are the normal approach, so consideration was given to semi submerged boards with the leading edge totally underwater, making it easier for fly to crawl down.

Other boards with specific purposes in mind have also been used. These are slide type boards for use with blue winged olive eggs and placed in the river complete with their valuable cargo of eggs just prior to hatching, after coming out of diapause during the winter months——–allied to this are container boards.

Often mistaken for eggs, but actually Algae magnified

A board with a slanted square front end at about 45 degrees to the surface laying area, of which half is under water and the other half above water line has several advantages. The board is attached to an overhead support being moored to the front section out of the water. This allows floating debris in the river to hit the angled front edge and slide underneath without catching up in the anchoring line. Boards of this design seem to attract more eggs to its front edge, particularly in the sheltered area directly behind the deflector where no such protection is provided on a simple plank.

It is essential that boards are cleaned at the end of the season as algae and old egg cases are not only unattractive to fly, but could pose a threat to new eggs in the form of infection / contamination.

Many egg laying spinners seem to prefer fairly fast, shallowish water or just below it, particularly with the presence of some weed mid stream, to crawl down, ( but some fly do prefer the margins ). Ranunculus it would seem, is one of the most desirable, and as this plant is becoming scare due to various reasons, low flow rates and swans etc. Fly boards moored in such locations do particularly well and act as a substitute for the lacking weed as a landing site.

If boards are placed in areas which are undesirable to fly, they have little effect and finding the naturally used site, all important for success.