Fly Fishing for Trout Home
User Password
or register.
Scientific name search:

> > Hendrickson size

The Specimen

Ephemerella subvaria (Hendrickson) Mayfly DunEphemerella subvaria (Hendrickson) Mayfly Dun View 9 PicturesI collected this male Hendrickson dun and a female in the pool on the Beaverkill where the popular Hendrickson pattern was first created. He is descended from mayfly royalty.
Collected April 19, 2006 from the Beaverkill River in New York
Added to by on April 22, 2006

The Discussion

JpsullyJanuary 10th, 2007, 11:59 am
bedminster, nj

Posts: 4

Looking at the fifth photo from the top (the one with the ruler under the fly), it would appear that if you were to rotate the fly just a bit to the left, it would show that the fly is over one inch (25mm) long. That would make it twice as long as any Hendrickson I have ever seen. The average Hendrickson (to the best of my knowledge) is usually around 10-12mm (or about 1/2 inch), hook size 10-12. The hook size just doesn't seem to fit either. Where am I going wrong when looking at this fly (and hook)?

MartinlfJanuary 10th, 2007, 12:42 pm
Palmyra PA

Posts: 3125
JP, Unless I'm mistaken, I believe that the ruler Jason is using is metric, that each little increment is one mm. I then see the bug measured at about 9-10 mm in the photo (not counting, of course the tails), and size 12 fits your accurate observations about the typical Hendrickson hook size. Now, when and where will we start seeing this bug come spring? I'm ready now.
"He spread them a yard and a half. 'And every one that got away is this big.'"

--Fred Chappell
TroutnutJanuary 10th, 2007, 12:54 pm
Bellevue, WA

Posts: 2706
Louis is right: it's a metric ruler, and the fly's body is about 11mm long.
Jason Neuswanger, Ph.D.
Troutnut and salmonid ecologist

Quick Reply

You have to be logged in to post on the forum. It's this easy:
Username:          Email:

Password:    Confirm Password:

I am at least 13 years old and agree to the rules.

Related Discussions

TitleRepliesLast Reply
Re: Crane Fly
In the Identify This! Board by DayTripper
6Jun 1, 2013
by Crepuscular
Re: Yellow Breeches
In Fishing Reports by Wbranch
2May 11, 2008
by Wbranch
Re: Dark Sulphur
In Male Ephemerella excrucians Mayfly Dun by Martinlf
10May 24, 2009
by Wiflyfisher
Re: caddis larva beh;a;vior question (really!)
In Brachycentrus Caddisfly Pupa by CaseyP
10Dec 20, 2009
by LittleJ
Re: How big?
In the Photography Board by Trevorh1989
8Dec 25, 2010
by Keystoner
Re: Questions about B&H Trout Fishing, Wisconsin Dells
In Beginner Help by Starry
3Jun 18, 2012
by Redspeed
Re: One of the nicer brookies of the year.
In the Photography Board by Smallstream
4Aug 16, 2007
by Wbranch
Re: A few photos from recent outings (guide's days off)
In General Discussion by Crepuscular
8Jun 12, 2017
by Jmd123
Re: Hate to do this again....
In Acroneuria abnormis Stonefly Nymph by PeterO
5Oct 1, 2010
Unit of Measure
In Male Ephemerella subvaria Mayfly Dun by Flybyknight
Most Recent Posts
Re: Gila Trout near Silver City NM
In the Photography Board by JJTrout (Martinlf replied)
Northern Iowa Stonefly
In the Identify This! Board by Pdcox
Green Sedge
In the Identify This! Board by Wiflyfisher
Re: Unidentified Baetidae
In the Identify This! Board by Benthosfan
Re: Please confirm Ephemerella needhami
In the Identify This! Board by Jorowan (Doug1234567 replied)
Re: Where to find Rio Grande Cutthroat Trout
In General Discussion by JJTrout (Martinlf replied)
Re: Fishing rod sensitivity!
In Gear Talk by Grayson (OliverJames replied)
Re: Repeat of Niangua ID thank you Roger
In the Identify This! Board by Pdcox (Taxon replied)
Re: Stonefly ID Please.
In the Identify This! Board by OldHasBeen (Troutnut replied)
Re: Stone fly on the Niangua River in Missouri
In the Identify This! Board by Pdcox (Taxon replied)