Scott,
Thanks for the clarification. Tom D. is doing great. Now without trying to
murk up the waters, Bob Smith's "Native Trout of North America" discusses a
northern and southern Dolly Varden.
"It differs from the northern race in having significantly fewer vertebrae
and fewer gillrakers".
Any thoughts on this? I would suppose that Dollies, Bulls and Arctic char
are decedents of a similar ancestor and these slight morphological changes
are environmentally caused due to isolation?
Irregardless, I appreciate your response to the former post.
David Duvall
----- Original Message -----
From: Scott Craig <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Sunday, January 28, 2001 8:06 AM
Subject: Re: bull trout/Dolly Varden
> David (Say hello to Tom Dresser) and Wes,
>
> I sent that person an e-mail, but it was returned- the account was
> expired.
>
> In regards to correctly identifying bull trout from Dolly Varden, It is
> extremely difficult to differentiate the two species in the field
> (Although its easy to send a fin clip to the lab). The only scientific
> way to do this in the field is to use the Hass Linear Discriminate
> Function (see below). I do not recommend that anglers try and count and
> measure the variables because it takes quite a long time and you would
> probably stress the fish beyond its limit to recover (Branchiostagal and
> anal fin rays are very difficult to count).
>
> This summer I caught some small resident native char (<190 mm) above Sol
> Duc Falls, which are known to be pure Dolly Varden (Not all Dolly Varden
> are anadromous). These Dolly Varden had small heads that looked like
> rainbows, and did not look at all like the bull trout I have seen in
> Eastern Washingtin! When I fish the Skagit system, which is known to
> contain both char species, I cannot I.D. the char to species with 100%
> certainty!
>
> The article from the Skagit Valley Herald was in response to the USFWS
> proposal to utilize a provision in section 4(e) of the Endangered Species
> Act "Similarity of Appearance"; see Federal Register 66:1628 (Jan 9,
> 2001). Karolee had the reporter call me, and I talked to her for 1/2
> hour about the fish. It seems as though IUve missed my chance of being
> quoted in the Skagit Valley Herald- I'm crushed. The USFWS proposes to
> use the provision, because we foresee people utilizing misidentification
> as a way to try and get out of enforcement violations. The reporter
> thought that this proposal was aimed at anglers- it is not! When the bull
> trout was listed, the USFWS determined that "existing" fishing regulations
> were adequate to "conserve" the species. As you know, the State treats
> bull trout and Dolly Varden as "Native Char", so if catch and keep is
> allowed, such as in the Skagit, Snohomish and one small eastside river, it
> does not matter what species you retain. The proposal is intended for
> "harm and harass" type violations, such as destruction of habitat.
>
> I'm not a taxomomist, but I personally feel that bull trout and Dolly
> Varden should be subspecies. As most of you know, cutthroat trout have
> 10+ subspecies. Kurt Kraemer (WDFW) believes that bt/DV are spawning
> together in the Skagit system, this would indicate that a "biological
> species" type approach in identifying them as separate species is
> incorrect. The American Fisheries Society (1980) concluded that
> morphological and genetic work from Ted Cavender (1978) and others was
> sufficient to separate bt/DV.
>
> Here is an abstract from a true bull trout/Dolly Varden expert- Gordon
> Hass.
>
> Haas, G. R. and J. D. McPhail (1991). "Systematics and distributions of
> Dolly Varden (Salvelinus malma) and bull trout (Salvelinus confluentus) in
> North America." Canadian Journal of Fisheries and Aquatic Sciences 48(11):
> 2191-2211.
>
> "Dolly Varden char in North America separate into two species: Doll Varden
> (Salvelinus malma (Walbaum)) and bull trout (Salvelinus confluentus
> (Suckley)). Principal component analyses reveal two distinct
> morphotypes, and a linear discriminate function is derived (based on three
> field measurable variables) for their consistent classification. No single
> character can always distinguish both species, although branchiostegal ray
> number often will. The morphology of the two species remains relatively
> constant across their large ranges. The two species occur in strict
> sympatry in several areas with no evidence of interbreeding. The two
> species also exist parapatrically or syntopically and appear to exhibit
> broad scale competitive exclusion in these situations. Dolly Varden are
> distributed largely along the coast and range further north, while bull
> trout are mostly interior and range further south. Laboratory crosses
> demonstrate that the morphology of both species distinctive when they age
> reared under similar conditions and that their artificial hybrids are
> morphologically intermediate. No such natural hybrids were conclusively
> found, and there is no evidence of introgression."
>
> I'm sure that by now, you are dying to see the Linear Discriminate
> Function. Here it is-
> LDF=.629BR + .178AFR + 37.10 UJL/SL - 21.8
> Where BR represents the total Branchiostagal Rays (both sides), AFR =
> total Anal Fin Rays, UJL = Upper Jaw Length and SL = Standard Length.
>
> When you measure the four parameters and compute the equation, values
> greater than zero are bull trout, values less than zero are Dolly Varden.
>
> The main problem with the Hass LDF is that people are more likely to count
> fewer than actual branchiostagal or anal fin rays. Since Dolly Varden
> have lower numbers of branchiostagal rays, and sometimes lower counts of
> anal fin rays; miscounts almost always favor a Dolly Varden conclusion.
>
> If anyone catches "Native Char" in the salt, please let me know!
>
> ___________________________________________________________________
>
> On Sat, 27 Jan 2001, David Duvall wrote:
>
> > Scott,
> >
> > Several weeks I sent you an email of a guy who spent considerable time
> > fishing and catching bull trout/dollies in the salt. Perhaps a year ago,
you
> > mentioned on this list that you were looking for info on these species
in
> > the salt. I was just wondering if this guy was a flake or if he was able
to
> > help you out. A couple of weeks ago the "Skagit Valley Herald" ran an
> > article on bull trout/dollies. They quoted Karolee Owens (you probably
know
> > her since she is a USFW'er too) and Curt Kraemer, but I am still
confused.
> > I have talked to Dr. Paul James at CWU and he said it is virtually
> > impossible to distinguish between the two, yet many people say they can.
I
> > am somewhat fascinated by these two species and would love to be able to
ID
> > them each when I see them, if possible. I am a temp bio for Grant Co.
PUD
> > and I currently have another month before I go back to work (lots of
time on
> > my hands). You got any suggestions?
> >
> > David Duvall
> >
> >
> >
> >
> >
> >
> >
> > ----- Original Message -----
> > From: Scott Craig <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>
> > Sent: Wednesday, January 24, 2001 7:13 PM
> > Subject: FYI- WDFW FF angling proposal
> >
> >
> > > WDFW is seeking comments on the following propsal-
> > >
> > > see http://www.wa.gov/wdfw/do/newreal/jan2201a.htm
> > >
> > > Proposal would allow anglers with certain disabilities to use spin
gear in
> > > fly fishing-only waters
> > >
> > > Olympia- At its next regular meeting in February, the Washington Fish
and
> > > Wildlife Commission will hear public testimony and consider a proposal
> > > that would allow anglers with permanent disabilities to their upper
> > > extremities reasonable access to waters designated fly fishing-only.
> > > The meeting is scheduled for Feb. 9 and 10 at the Best Western
> > > Southcenter, 15901 West Valley Road, Tukwila. The exact time the issue
> > > will appear on the agenda is still to be set; check the agency's web
site
> > > for details later this month or call the Commission office at (360)
> > > 902-2267.
> > > Current fishing regulations allow only fly-fishing gear, which
typically
> > > requires two hands and mobility, to be used in waters designated as
"fly
> > > fishing-only." There are 20 waters in Washington designated for fly
> > > fishing-only. Under current regulations, anglers with disabilities
cannot
> > > effectively take advantage of the opportunities these waters provide.
> > > Allowing anglers with disabilities use of spinning gear to fish on
these
> > > waters will provide them access to these opportunities, because spin
gear
> > > may be operated with one hand.
> > > The issue was raised this past fall when an angler with a permanent
> > > disability protested changing North Silver Lake in Spokane County to a
fly
> > > fishing-only water, contending that restrictions on fly fishing gear
limit
> > > his ability to fish in fly fishing-only water. Subsequent discussions
> > > between the angler, USFWS, the state Attorney General's Office and the
> > > WDFW resulted in an agreement to modify the agency's fly fishing-only
> > > definition.
> > > Commissioners are expected to take testimony, then discuss and decide
on
> > > the proposed regulation change. The proposed rule would allow anglers
with
> > > the inability to use one or both upper extremities to apply for a
> > > fly-fishing special use permit by presenting a letter from a
physician.
> > > The fisher would be issued a special use permit in the form of a
letter,
> > > which he or she would be required to carry while using spin-casting
gear
> > > in fly fishing-only waters.
> > > Gear regulations with the special permit would include:
> > >
> > > * Spin-casting gear with a casting bubble would be allowed.
> > > * Monofilament line with no limit on the breaking strength of the
> > > line would be allowed.
> > > * The leader beyond the bubble could not exceed 15 feet in length or
> > > have a breaking strength greater than 12 pounds.
> > >
> > > Hook size and barb restrictions, fly fishing requirements and bait and
> > > weight prohibitions would not change.
> > >
> > >
> > >
> >
****************************************************************************
> > > Scott D. Craig The members of this genus
(Salvelinus)
> > > Fisheries/Aquatic Biologist are by far the most active and
handsome
> > > U.S. Fish & Wildlife Service of the trout, they live in the
coldest,
> > > Lacey, WA. cleanest and most secluded
waters.
> > >
> > > Check out the homepage No higher praise can be given to
a
> > > http://www.eskimo.com/~craigs Salmonid than to say, it is a
charr.
> > > (Jordan and Evermann 1896)
> > >
> >
> >
>
>
****************************************************************************
> Scott D. Craig The members of this genus (Salvelinus)
> Fisheries/Aquatic Biologist are by far the most active and handsome
> U.S. Fish & Wildlife Service of the trout, they live in the coldest,
> Lacey, WA. cleanest and most secluded waters.
>
> Check out the homepage No higher praise can be given to a
> http://www.eskimo.com/~craigs Salmonid than to say, it is a charr.
> (Jordan and Evermann 1896)
>
