As we progress into summer, many of the mayflies that are hatching will be of a lighter color than earlier in the season, and fly-fishers will often use flies such as Sulphurs and Light Cahills as imitations of the naturals to successfully catch trout from now through September. 

A while back, Streamside commented on the story of Dan Cahill, the fictitious railroad train worker who was credited for stocking the Delaware River with rainbow trout. And now that we are seeing the seasonal use of Light Cahill flies, the mythical Mr. Cahill is also lauded on dozens of websites and otherwise credible sources (such as Orvis.com) for creating the Light Cahill fly – another invalid acclaim.

For those who missed the Myth of Dan Cahill, a brief explanation:

A couple of years ago, Ed Van Put, historian and avid researcher for the past 40 years of the history of trout fishing, devoted many hours searching for information on Dan Cahill, including the Library of Congress’s website as well as a good number of New York and Pennsylvania newspapers from around the town Cahill supposedly lived during the period from 1869 to 1929. 

However, despite being touted a “fishing authority”, the name Dan Cahill never appeared. 

Ed also searched the Erie Railroad Internet Employee Archives, the United States Federal Census Records, and the New York State and Pennsylvania State Census Records from the years 1860 to 1910, but was unable to find a Dan Cahill from anywhere in the Delaware River watershed. Ed found no evidence that Dan Cahill even existed, and stated “History should be verified by dates, testimony, and supporting documentation.”

He shared that the Light Cahill dry fly has an interesting history with ties to the Cahill fly pattern that originated way back in the mid-1800s, and was attributed to John Shields, a professional fly-tier from Brookline Massachusetts. John was born in Ireland in 1827, and gives credit to a Dublin fly-tier for the origin of the Cahill pattern, who would “on occasion, after making a fly, put it to Shields’ ear and ask if he heard it ‘buzz.’” 

The pattern was probably created sometime prior to 1862, which was the year Shields migrated from Ireland to America, the same year his son was born. At the time, the Cahill started out as a wet fly, and was tied with wood duck wings and tail, a blue-gray body and red-brown hackle.

Shields most likely brought the Cahill to America with him, as by 1876, it was being tied by Sara J. McBride a professional fly-tier from Mumford, New York, who learned to tie from her Irish-born father, John McBride. The two advertised their flies as “The Standard Flies for American Waters,” flies that were imitations of American insects. 

In the late 1880s, after brown trout were introduced in the Catskills, the primary method of fishing for trout was to cast two wet flies downstream and across the current; one of those flies was most often a Cahill, for many years the most popular pattern on the Beaverkill. 

By the late 1890s, floating flies were beginning to become popular, and one of the first to experiment with turning wet flies into early dry flies was Theodore Gordon, ‘the father of American dry fly fishing.’ 

Gordon worked on lightening the color of the original Cahill fly pattern to use when a “pale blue” mayfly was hatching, changing the body from blue-gray to a pale blue, and lightening the hackle from red-brown to light brown; he called his creation a Light Cahill.

In 1916 the Light Cahill underwent another transformation by William Chandler, a Sullivan County resident and early fly-tier who was greatly admired by sportsmen in the area. Chandler was credited by Theodore Gordon, Roy Steenrod, Harry Darbee, Art Flick and Preston Jennings with creating the Light Cahill as we know it, and tied the fly with a much lighter appearance, using cream fox fur for the body, and pale ginger for the tail and hackle, switching from using wood duck to pale ginger hackle fibers for the tail. 

Chandler’s pattern for the Light Cahill became popular in the Catskills in the 1920s and 30s and is still the standard for the pattern we use today.

Here is the pattern as was tied by William Chandler, that appears in Catskill Flytier by Harry Darbee with Mac Francis; Harry stated, “Another of the best dry flies ever devised.”

Wings: Flank of woodduck or mandarin drake

Tail: Pale ginger cock hackle fibers

Body: Cream-colored fox dubbing

Hackle: Pale ginger cock hackle

Hook: Sizes 8 to 20