In Search of Answers

—–Original Message—–
From: Mary Peacock

Sent: Friday, January 08, 2010 9:48 AM
To: David & Carmela Kortum
Subject: Re: Willow/Whitehorse Cutthroat Transplants…

David – it really is a bummer about these fish.  Here we had native cutthroat that were wonderfully adapted to desert environments.  People didn’t know what they had.  The planting of rainbow trout across the west has caused no end of problems.  I would be willing to analyze any samples provided to me from *****.  I do have ~ 25 of them right now and have not really looked closely at the allelic variants in these fish, but I will do this so that we can continue our discussion of what to do with *****!  I suggest you send me gentle reminders as I have lots of projects and things tend to get put on the back burner : – )

Mary

UNR - Mary Peacock - Associate Professor | Co-Director

David & Carmela Kortum wrote:

Mary,

Thank you for your detailed reply to my questions.

Indeed, the complexity for separation of the trout—with genuine alvordensis potential—in ***** Creek from the hybridized and non-alvordensis specimens, is one of the most daunting aspects a successful project would face.  (Projects in the past utilizing visible phonotypical characteristics to “separate” fish, have probably eliminated many pure specimens, as well as left hybridized fish in the mix.)

Dr. Behnke has maintained that the whole of meristic identifiers are diagnostic, though obviously we wouldn’t benefit by having to resort to dissection to ascertain the whole count (pyloric caeca).  We may be able to ascertain other meristic characters—without injuring the fish.  Our efforts have been looking toward new and comparatively inexpensive ways of identifying, isolating and protecting the fish while at the same time allowing for genetic verification or identification of what is extant in the ***** system.

Of course, some of us have wondered what happened to the fish in Jackson Creek.  Some have fished many of the tributaries that (should have) held alvordensis in the past.  As for Virgin Creek, it appears that Nevada has made it off limits for fishing (Sheldon Antelope Refuge), unless private property is exempt.  Although we haven’t given up on the prospect that there may still be alvordensis out there — somewhere.

Thank you again for your reply.  Your input is appreciated.

Respectfully,

David Kortum

—–Original Message—–
From: Mary Peacock
Sent: Thursday, January 07, 2010 4:02 PM
To: David & Carmela Kortum
Subject: Re: Willow/Whitehorse Cutthroat Transplants…

David – I can’t really answer your first question – you would have to ask Tim Walters or Ray Perkins of ODFW as they have done all of the sampling and I haven’t even been to these streams.  Tim did mention that the some of the fish in Little McCoy Creek had short opercula.  Our Steen’s mountain genetic analysis is in press in the scientific journal Transactions of the American Fisheries Society.  I can send you a reprint when it comes out.  We did find that the Steens and Willow-Whitehorse differ in the amount of genetic variation.  Steen mountain populations have allelic variants that are no longer found in Willow-Whitehorse which suggests these populations may have gone through a decline sometime after the fish were translocated to the Steens streams.  We recommend that the Steen populations be included when considering management of the Willow-Whitehorse LCT.

Unfortunately there is no way to conclusively identify Alvord cuts at this time either phenotypically or genetically as there are too few preserved specimens to establish diagnostic characteristics for this species.  Robert Behnke’s description in his 1992 book is the best we have and some of the characteristics of Alvords can only be assessed by dissection.  But as the fish in ***** are hybridized with rainbow I doubt there are any pure Alvord left.  In my experience trying to identify a “pure” cutthroat from a hybridized cutthroat by just looking at it is almost impossible.

The best that we could do at this point would be to run hybrid loci on any samples collected and if we found any that weren’t hybridized then use the suite of cutthroat trout markers and look for unique variants, but even this would not allow us to conclusively say these are Alvords.  Behnke writes that there may have been a few pure Alvord cutthroat left in the upper Virgin Creek above a barrier, but believes rainbows were planted here in the 1970s and as a result feels there are no pure Alvord left.  Even if you did find pure Alvord in ***** you would have to remove them from the stream to eliminate the chance of these individuals mating with rainbow.  Starting a breeding program with such individuals would be challenging and expensive.  It would have to go hand in hand with poisoning out ***** to get rid of the hybrids and rainbows.  Conversely these fish could be planted in other waters.  In 1986 fish that looked like cutthroat were translocated from Virgin Creek to a Jackson Creek in the Lahontan basin which was fishless.  I am not familar with this stream but I imagine the Nevada Division of Wildlife is. These might be a better bet for recovering an Alvord phenotype at this time.

Mary Peacock

UNR - Mary Peacock - Associate Professor | Co-Director

From: David & Carmela Kortum
Sent: Monday, November 23, 2009 8:38 PM
To: Mary Peacock
Subject: RE: Meristic characters of ***** Creek specimens / Genetic Considerations

Hi Mary,

Dave Kortum here, with what is perhaps an overdue follow-up regarding our previous chats at the end of September.  We all hope that all’s well for you and yours at the University of Nevada, Reno.

In part, we’re checking in regarding the Tim Walters sampling from ***** Creek to see if any allelic variants were identifiable?  There is also some curiosity regarding the Willow/Whitehorse Cutthroats (humboltensis) that were transplanted to streams on the eastern Steens range—whether they’ve adapted with any notable change or distinction in typical outward appearance?

Based on meristic counts (spotting, coloration; and scale, gill raker and pyloric caeca counts on the few casualties over the past two years) it does seem that we’re overall dealing with a limited percentage of the population that shows alvordensis potential.

Perhaps, by efficiently noting meristic data of trout in the field, the trout ultimately genetically tested could yield a meaningful percentage of differentiable DNA.  It is truly unfortunate that Hubbs and Miller overlooked ***** Creek (concluding based on flow in the lower regions, that it did not harbor trout).  A question that still persists with me; is whether ancient lakeMeinzer contained trout — and whether there was, in pluvial times, overflow into the *****Basin.  The geography would seem to support that possibility—though I’ve yet to get an answer from a geology department regarding that question.

We’ve also noted a fair percentage of trout with gill-plate anomalies.  Often these trout (with deformed or short gill-plates—not even covering the gills) are symmetrical (same on both left and right sides).  We have photos of some of these… and we’re a bit curious whether this is a genetically caused condition or whether it is a developmental phenomenon.

All the questions aside, we have photographed quite a few trout that, based on historical meristic data, would seem to fit into the alvordensis classification better than any other.  We can certainly share some of these photographs with you if you would like.

If further sampling of ***** Creek trout ultimately comes to fruition—are there (what are the) specific genetic testing methodologies that you would recommend in order to “nail-down” the genome of the unique specimens in the system?

Providing that the “powers that be” endorse this more focused course of action that we’re working toward, your assistance would and will be greatly appreciated.

Thank you again for your time, and for your reply to our inquiry.

Respectfully,

David and Carmela Kortum

—–Original Message—–

From: joe tomelleri
Sent: Wednesday, October 14, 20098:16 AM
To:
Patrick Trotter; ‘David & Carmela Kortum’
Subject: Re: Meristic characters of ***** Creek specimens

I wonder what Mary Peacock will find when she looks at the Steens’ Mountain Willow/Whitehorse transplants?   It would be interesting, and could be helpful to know what Mosquito and Pike Creek have in regard to phenotype too.   A small number of transplanted individuals could have skewed the original geno and phenotype in any of these populations, including ***** creek.

I am still curious of 009 which has gill raker # well below the known range of Lahontan (and outside of range of WW and alvord), but a scale count which falls only within known range of Lahontan.    I won’t brood over it, as you say Pat; we need a lot more samples.

Best regards,

Joe T.
www.americanfishes.com

Joe Tomelleri - American Fishes

From: David & Carmela Kortum
Sent:
Tuesday, October 13, 200912:00 AM
To:
Patrick Trotter‘; ‘joe tomelleri’
Subject: RE: Meristic characters of ***** Creek specimens
Hi Patrick, Joe,

Thanks Patrick, for your detailed analysis of the three casualties from 2008/09.  The analysis is more encouraging than I’d anticipated.

The specimens from “08 and Sept. ’09 would, of course, have not made it “into the bucket,” but since they were available, they were sent along as examples of the non-alvordensis trout of the system.  I’m perhaps a bit surprised that ***-007 had a high scale count (as I suspected possible rainbow/redband introgression — we caught a rainbow/redband [no cutt marks] in the same proximity.)  There are also many trout in the system that readily fit into the standard humboltensis and henshawi phenotypes.

Your thought regarding a local adaptation certainly is worthy of consideration.  It seems that Mary Peacock and Casey Dillman have each alluded to what might be defined as “plasticity,” adaptations of trout, occurring over a relatively short period of time.

However, I’d propose a question: If ***-008 had been the only trout sent to you, what would have been your primary thought(s)?

—————————————————————————————————————

Carmela and I mentioned the unusual number of trout that we’ve caught where the gills extend beyond the gill plate (on both sides).  In some cases the outer rim (several millimeters) of the plate is completely missing.  Of these unusual gill-plate formations, they are often symmetrical on both sides.  To us, it would seem probable that these anomalies are genetic in nature.

Behnke refers to redbands (KlamathBasin) developing differing gill raker counts depending on whether they were lake form or resident stream form (with the stream form having fewer gill rakers).

Questions arise regarding what type of adaptation might occur with over a century in a new environment:  Are meristic factors, such as gill rakers, environmentally affected (plastic)?  In this case is hybridization of the divergent species extant in the system causing an anomaly?  Are there environmental extremes causing developmental “challenges” for these trout?  Perhaps these equate to a lower gill raker count.

Not exactly the type of questions that demand an immediate answer… but may play a role in solving the mystery of the ***** Creek trout.

In the meantime, the results of your analysis are encouraging to us.  In general, we’d expect that up to 95% of the trout in the system would not “make the bucket” based on the visible meristic identifiers (earliest known spotting pattern).  The gill rakers may seem low, yet I’ve been told that the original alvordensis collection is also quite limited (thus difficult to make unqualified determinations regarding “standards.”)  Yet, we now have a phenotype (***-008) with lateral series scales and pyloric caeca within known ranges, with the known original spotting pattern, rose opercales, rose lateral line, and deep purplish-rose fins, with the gill raker count only one less than previously recorded samples.

We still hope that Alvords may be found in a system that is not such a “soup,” as ***** Creek is, and that the solution would then be self-evident and quite obvious for all to see.  In the meantime it would seem logical to persevere with the “hope at hand” to thoroughly document what the identifiable Alvord phenotypes yield in terms of the hidden meristic identifiers, and ultimately, hopefully, genetic markers.

Carmela and I trust that this winter will provide some time for sound strategizing and then perhaps proposing a cost-effective methodology to ultimately secure live specimens for detailed meristic and genetic analysis.

Thank you again Patrick for your attention to the meristic characteristics and for your detailed analysis of the specimens.

We’ll look forward to keeping in touch and sharing thoughts as they progress — so we can all sharpen them together.

Respectfully,

David & Carmela

——————————————————–

An Interesting statement regarding meristic counts from a Copeia Article, 1991:

Copeia, 1991 #3 Pg. 854 “Behnke (1986) analyzed meristic characters of fish from Virgin Creek and stated that ‘a few of the oldest fish remain pure (cutthroat trout).’   However, meristic characters can be influenced by environmental effects and may not reflect influences caused by introgressive hybridization (Greenfield and Greenfield, 1972: Leary et all., 1984; Camton, 1987).”

——————————————————–

—–Original Message—–
From:
Patrick Trotter
Sent:
Thursday, October 08, 20094:12 PM
To: ‘David & Carmela Kortum’; joe tomelleri
Subject: Meristic characters of  ***** Creek specimens

Hi folks,

I’ve completed my meristic character counts of the three specimens from ***** Creek, and I have to say up front that my news is not encourgaging.  Even so, here’s my report.

First, the specimens.  I coded these as follows:  ***-007, capture date 2008; ***-008, capture date July 2009; and ****-009, capture date September 2009.  Based on its spotting pattern, ***-008 was regarded as the candidate Alvord phenotype.

***-007:  Fork  length (FL) 203 mm, Standard length (SL) 182 mm.  Despite its long time in a home freezer, Gua-007 arrived in good shape and its coloration and spotting were easily discernable.  I was able to get a good lateral series scale count, but the fish had been field-dressed and cleaned, so all internal organs were missing as was the gill chamber, precluding both gill raker and pyloric caeca counts.  Colors as-received grayish olive on top and upper sides; a broad, fairly bright pink band along the lateral line and pink colors also on the opercle and preopercle; lower sides grayish with yellow cast; belly light gray to white.  Only one fin (left pelvic) was present and that fin was orange.  Many spots distributed all over the body, with rather more spots above that below the lateral line; many spots also on the caudal fin.

***-008 (the putative Alvord):  FL 200 mm, SL 178 mm.  This specimen arrived in poor shape, pretty beat up.  Nevertheless, I was able to discern colors and spotting pattern, and despite some internal decomposition, was able to extract the stomach-intestinal tract intact for pyloric caeca count.  The gill arches were in good shape enabling the gill raker count without problem.  Body colors essentially as above, with a broad, fairly bright pink band along the lateral line and pink also on the opercle and preopercle.  Pectoral, pelvic, and anal fins were a deep plumy rose color.  This specimen had only 23 spots on the left side of its body, all distributed posteriorly from the vent back to the caudal fin.  There were no spots at all on the body forward of the vent.  The caudal fin was only lightly spotted.

***-009:  FL 210 mm, SL 186 mm.  This specimen, the most recently captured, arrived in excellent shape.  Body colors essentially as above, and also like the others, this specimen had a broad, fairly bright pink band along the lateral line with pink also on the opercle and preopercle.  Pectoral, pelvic, and anal fins orange.  The spotting of this specimen was similar to ***-007, with many spots distributed all over the body but rather more above than below the lateral line.  Caudal fin heavily spotted.

I counted lateral series scales, gill rakers, and pyloric caeca, all according to the procedures outlined in Behnke (1992, page xix).  Taken together, these three characters serve best to distinguish among the  western-basin Lahontan, the Willow-Whitehorse, and the original Alvord  subspecies.  My results are in the table below.  These should be compared with the chart of meristic characters I gave you earlier, which shows both the range of values and population averages for each cutthroat subspecies either known to have been stocked or presumed to be present in ***** Creek.

Gill Rakers

Pyloric Caeca

Lateral Series Scales

***-007

163

***-008

19

35

141

***-009

17

36

170


As you’ll see, ***-008, the putative Alvord, has too few gill rakers to be consistent with Behnke’s description of the original Alvord subspecies, although its pyloric caeca and lateral series scale counts are within the original Alvord range.  ***-008 also has too few gill rakers and too few pyloric caeca to be consistent with the Lahontan subspecies.  On the other hand, all of its characters including gill rakers are congruent with the Willow-Whitehorse subspecies.

The same could be said for the heavily-spotted ***-009.   Although it has a few more scales than Behnke specifies for the Willow-Whitehorse upper limit, its low number of gill rakers and low pyloric caeca count places it firmly in the Willow-Whitehorse camp.

Although just 1-3 specimens are way too few to be jumping to any conclusions here—and granted, I’ve never seen any Willow-Whitehorse cutthroats with the bright pink lateral bands like these ***** Creek cutthroats display, at least not in their native streams—still, the way these variously-spotted specimens (even the scale count for ***-007) seem to cluster in the Willow-Whitehorse range makes me wonder if, rather than a hybridized relict Alvord population, we might be dealing with an array of local adaptations of the Willow-Whitehorse form in the new (for it) environment of ***** Creek.

Just something else to throw in the mix to think about,

Patrick Trotter

Patrick Trotter - Cutthroat Native Trout of the West

—–Original Message—–
From: David & Carmela Kortum

Sent: Friday, January 08, 2010 1:22 PM
To: ‘Mary Peacock’
Subject: alvordensis, ***** creek, future

Mary,

Good to hear from you again.  Of course we heartily agree regarding the plight of the Alvord cutthroat trout (and other native cutthroat and native species in general).

I’ll plan to keep you apprised of any specific progress / development regarding a ***** creek project.  The situation is remarkably complex for a number of reasons.

Thank you again for your reply and for all of the work you do (at the University of Nevada, Reno — and for the public in general).  …We’ll plan to “chat” in the future!

Respectfully,

Dave Kortum

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About kortumofdiscovery

Kortum of Discovery (a slight play on Lewis & Clark's Corps of Discovery) is a family team that is Affirming the Exceptional Beauty of Nature, one Adventure at a Time. With a focus toward rare and endangered species in the Great Basin and American west: discoveries, unique methodologies, and many “tall tales to tell” are continually being shared around the campfire!
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