Anglers learning from the swallows

ONE of the nice things about writing a column like this is that you get really interesting letters and emails from readers.

One of the less nice things is that you never get the time to answer them all individually.

So let me make a blanket apology. I did read them and appreciate them.

Sorry I didn't reply.

A couple of weeks ago I wrote a column speculating about why the swallows over the lake fly high on some days and low on others and whether, when they actually touch the surface of the water with their beaks, they are taking insects or having a drink. It was an article that contained more questions than answers.

A reader from Rathgar in Dublin has written to me with his thoughts on the matter. He is an observant fly fisherman.

"On warm bright days the flies (duns or sub-imago stage) hatch and rise quickly to a good height (light air pressure?).

The swallows and swifts, fly high and feed on them. On dull overcast days with a 'heavy' feel (pressure high?) the duns stay close to the surface and the swallows fly along the surface, often inches from the water.

This has made me always look to what the swallows are doing before I fish low flying swallows equals good fishing.

Seeing a Pied Wagtail on a rock jumping a few inches into the air to grab a fly or two is also a good sign."

This thoughtful reader then goes on to reinforce his point by calling on the authority of a man who was probably the greatest Irish fly fisherman and entomologist of all time.

"J R Harris holds that the weather affects the time a hatched fly takes to get off the water. The fly needs to dry its wings and also the heat affects the time it takes for its flight muscles to become functional (cold slows this down).

I know this to be true as the older I've got the harder it is for me to get out of bed on cold mornings ... J R Harris talks too about surface tension and the effects it has on flies and I wonder if high air pressure would increase the surface tension of the water and slow down hatching flies, bringing the swallows down lower?"

Our reader then goes on to urge me to get a copy of Harris' classic book, probably out of print, An Angler's Entomology.

I am pretty old, but when I was young I had the privilege of knowing the late J R Harris. I didn't know him socially but before he retired he worked behind the counter of Garnet and Keegan's tackle shop in Parliament Street in Dublin.

I WAS a young and inexperienced angler trying to work out the complexities of the insects that hatched on the Liffey in different months of the year.

He spent hours painstakingly dispelling my ignorance. It was not very profitable from the shop's point of view.

At the end of the tutorial I usually bought about two shillings worth of flies. I hope that's not the reason the shop closed down. But the cliché "a scholar and a gentleman" might have been coined to describe J R Harris.

And, although I have a small library of several hundred books on fishing, I do not have a copy of his An Angler's Entomology.

I don't suppose there is some other kind reader out there who has got one they would like to sell?

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