Scientist: Frog's decline threatens Sierra ecology

Grab your bear can or camp chair, kick your feet up and chew the fat about anything Sierra Nevada related that doesn't quite fit in any of the other forums. Within reason, (and the HST rules and guidelines) this is also an anything goes forum. Tell stories, discuss wilderness issues, music, or whatever else the High Sierra stirs up in your mind.
User avatar
caddis
Founding Member
Posts: 236
Joined: Sat Dec 03, 2005 7:01 pm
Experience: N/A
Location: Lemoore
Contact:

I guess the wrong buttons were pushed

Post by caddis » Sat Jun 03, 2006 7:32 am

10,000 lakes and 90% occupied by trout leaves 1000 lakes for frogs....not sure where the "a hundred of those lakes for frogs? Maybe even 200" figure comes from.

The point of my questions was to find out if MYLF's can survive in lakes that can't support a viable fish population. If yes, then there is enough habitat already for a "whole and healthy ecosystem here." Therefore, the main problem with the MYLF decline does not rest with the trout. This does not exclude them as an important factor in MYLF numbers being reduced, but as I said, reducing numbers in itself is not a cause for threatening extintion.


It's my contention that there is no need to remove fish from waters where fish can reproduce. Let the other lakes "die-off" (end restocking in lakes that can support a MYLF but not a trout) there is plenty of habitat and the solution to the MYLF should be sought elsewhere.


Image






User avatar
SSSdave
Topix Addict
Posts: 2872
Joined: Thu Nov 17, 2005 11:18 pm
Experience: N/A
Location: Silicon Valley
Contact:

Post by SSSdave » Sat Jun 03, 2006 6:01 pm

gdurkee, thanks for forwarding the response from the biologist. Some of those responding might go back and read my posts from the first page of this thread. I had stated that I saw a lot of high alpine lakes with frogs, tadpoles, and fish. But after reading the link gdurkee provided, it was obvious many of those were likely Pacific tree frogs and tadpoles. So those talking about seeing tadpoles in lakes might not be seeing the yellow-leggers.

I don't think there is anywhere close to trout in 90% the 10,000 or so lakes and ponds. Sometimes the number of lakes in the Sierra is given as 8,000 as there it depends on what is considered a lake. Many of the small shallow ponds dry up during summer. Whether 8,000 or 10,000 is used, it is obvious that number is considering the many small ponds.

My old copy of Ralph Cutter's "Sierra Trout Guide" lists less than 1750 lakes with fish. That includes all the named lakes plus a modest number of unnamed lakes in named basins that are just given numbers. There are of course far more unnamed lakes and ponds than named ones. In the Southern Sierra, there are a modest number of large unnamed lakes. Doubt if that is more than a hundred or two. There are many more medium sized lakes that might make for another few hundred. Generally we can say the majority of large and medium sized waters are named. After that are enormous numbers of small lakes and really small ponds. Most are too shallow for fish due to winter kill. In some alpine areas covered by glacially smoothed granite, such small granite pocket lakes are abundant. Even in some forest elevation areas that have been heavily glaciated there are large numbers of such small waters. A good example is the Letora Lake region of Emigrant Basin.

Given the number of lakes in Cutter's book then adding the large, medium, and small lakes and ponds with adequate depth that are unnamed lakes, I'd be surprised if there were even 3,000 lakes and ponds with fish and certainly less than 4,000.

Also since some of you in these later posts are voting, I'd like to vote too. I vote for stunted eastern brook. Their skin even looks like frogs so they must be eating frogs to look like that haha. And they certainly like to squirm around in lake shallows. Yeah remove the stunts! ...David

User avatar
SSSdave
Topix Addict
Posts: 2872
Joined: Thu Nov 17, 2005 11:18 pm
Experience: N/A
Location: Silicon Valley
Contact:

Post by SSSdave » Wed Sep 06, 2006 9:07 pm

Image

Over the holiday while on the trail above Lower Lamarck Lake, took the above pic of what looks to me to be a yellow-legged frog pollywog in an advanced metamorphosizing stage. The frogs I see in the high country usually become frogs late in September. One can see the legs on the side, spots along the three or so inch long body. Note the lodgepole pine needle nearby in the water. Sorry for the less than clear image but they didn't like me getting near them and we were in a hurry to reach our car down at North Lake. This pond is at about 10.7k on the trail a short ways beyond the lake outlet where it routes in a ravine before reaching the inlet creek to the lake. The ravine has considerable talus which covers the bottom of this quite shallow rocky pond. A pond that is never very deep as it is not part of a drainage system but rather likely is simply where the bedrock below the talus forms a small bowl that collects a shallow amount of water. Such ponds are abundant in the higher altitudes and where I often see tadpoles.

My reason for the post is in a previous post in this thread there was some research that stated yellow-legged frogs can only overwinter in deeper ponds or lakes so that all these shallow ponds probably held tree frogs or other species. If that were true then we need to be concerned. If not then there are thousands of small ponds and streams where the frogs can live while fish cannot. Something I had doubts about and seeing these pollywogs in this and other ponds now has me doubting this whole frog research once again as misleading with an agenda. Now I may be incorrect with that suspicion but someone is going to have to address this shallow pond issue with something more solid. In the mean time I'm going to be taking more pics like this when I'm out this month. ...David

User avatar
gdurkee
Founding Member
Posts: 763
Joined: Tue Nov 08, 2005 8:20 pm
Experience: N/A

Tadpole photo

Post by gdurkee » Mon Oct 09, 2006 1:20 pm

Dave:

I'm pretty sure that's a Pacific Treefrog. The eyes are on the side of the head vs. the mountain yellow legged which are more to the top
http://www.californiaherps.com/frogs/images/

The treefrog tadpoles develop to frogs in one summer season (I think...). The Mt. Yellow-legged take 2 or 3 seasons. They are also usually much larger and darker (almost black).

Also, if there's tadpoles around, there's almost always adults on the lake margins if it's yellow-leggeds. Tree frogs disperse almost immediately, though you often see them hippity hopping along the lake shore when they're becoming adults at the same time. They don't hang out there though. I don't think I've ever seen a pond with MYL tadpoles and no adults (though it probably happens).

George

huts

Post by huts » Mon Nov 06, 2006 10:28 am

George, I was paying attention to your argument until you started cussing at me. ("your #$@*&%^$ trout").
My argument is with the way this process was carried out. I filled out angler survey cards for a few years before I knew why this information was wanted. Questions to fish and game are frequently ignored or I recieve a response that is vague and/or patronizing("the issue is complicated" ="you do not have the intelligence to understand"). Sometimes it is deceitful. Sometimes I am treated with a level of respect that is only slightly better than cussing at someone who does not agree with you. (I am speaking of other issues along with the frog)
No one has ever asked for my input in the decision or kept me "in the loop" in spite of my obvious interest. It is not posssible for me trust the "powers that be" when it is clear that they feel the need to keep people out of the process.
The rest of my response to George will not be a part of this or any other post as I do not wish to participate in the same manner he has.

User avatar
ERIC
Your Humble Host & Forums Administrator
Your Humble Host & Forums Administrator
Posts: 3202
Joined: Fri Oct 28, 2005 9:13 am
Experience: Level 4 Explorer
Location: between the 916 and 661

Post by ERIC » Wed Nov 08, 2006 9:49 pm

Let's not let this great 'discussion' get out of control, people. :computer:

Cheers,
New members, please consider giving us an intro!
Follow us on Twitter @HighSierraTopix. Use hashtags #SIERRAPHILE #GotSierra? #GotMountains?
Follow us on Facebook: https://www.facebook.com/HighSierraTopix

User avatar
rlown
Topix Docent
Posts: 7368
Joined: Thu Oct 25, 2007 5:00 pm
Experience: Level 4 Explorer
Location: Wilton, CA

Post by rlown » Thu Oct 25, 2007 5:20 pm

Just got back from North of Tuolumne Meadows at Virginia and Upper Mattie lakes this late Sept. We checked in for our wilderness permit and we were off. We even took two new people who've never backpacked or caught a huge Brookie before. These lakes are off trail so you're on your own out there. These lakes held 14" - 24" Brook trout. when we got to Upper Mattie on the second day, we found gill nets. There was a phone number on them to call (209) 379-1995. It was fishless after being excellent for 20 years.

The next day we climbed over the ridge to Virginia Lk, thinking there was NO way they'd do that to such a large lake with the really big brookies. (we still didnt know what was going on at the time)

We descended into V only to find the gillnets (and several Dipper birds entangled close to shore). So, it was a blown trip, but you could still catch all the 8" trout you wanted in glen aulin. kinda disgusting.

I guess my point is it's great that we want to save the frog. There is habitat near these lakes that would have worked to raise populations (as those were gillnetted as well), but why rape the nice lakes with the big fish. Take all the silly lakes with thousands of 8" trout.

I understand the science and intent, but now i'm gonna need to buy a frog gigg'n stamp to visit my favorite lake ever again, and that wont be half as fun as the fish. I vote Trout (guys, btw, we dont get a vote as the MYLF will go on the endangered list)

Regards,

Russ

User avatar
AldeFarte
Topix Regular
Posts: 215
Joined: Mon Jan 09, 2006 10:46 pm
Experience: N/A
Location: Eklutna, Ak.

Post by AldeFarte » Thu Oct 25, 2007 9:59 pm

:( rlwon, I can totally sympathize with your blown trip, after no doubt a long haul and much anticipation for a place you know has large fish. I had a similiar occurance , but it was not about the lovely mylf. It involved gill nets,tho. I have done plenty of gill netting for salmon and you can believe me when I say they are indescriminate. It's called bycatch. If there is bycatch with 4 inch web, what do you think think gets entangled in the size web they use for 12 to 16 inch trout? But hey! It's ok. After all, it's for the "better" good. People on the mylf bandwagon are true believers and they can rarely be turned from the dark side. Or else they have a financial investment. After all, they don't give many grants for studying the pacific tree frog. Or the western jack rabbit, or the blue belly lizard. All common and thriving critters. We can only hope that someone with sanity will persuade the powers in charge of a better way to help the mylf than gill netting trout! Life has a tenacity, but me thinks the frog cannot withstand the virus. I know it can survive the trout. jls

User avatar
mikehike
Topix Regular
Posts: 220
Joined: Fri Jul 21, 2006 5:56 pm
Experience: N/A
Location: Clayton, ca
Contact:

Post by mikehike » Fri Oct 26, 2007 11:01 am

Where is the end game here?
How many lakes do they propose to gill net?

How many ducks will this kill?
I have been told the gill-nets only kill the trout, I don't beleive it.

Do you think non-native trout add value?
Has anyone studied this?

Maybe more food for bears, bobcats and mtn lions at high-altitudes?

I hope this is not an all or nothing mentality, fisherman appreciate wildlife as much as anyone. I safely release 90% of the fish I catch, the ones I keep I eat, thats usually one fish. But I guess to the frog people would rather have me bash it to mush on a rock. I like frogs and I don't have a problem with preserving native species, its wonderful. Can we have both? I'd say thats easily accomplished, with the sheer number of lakes in the Sierra, not a problem.

Is there a list of lakes they plan to eradicate the trout from?

I am sure its in the earlier posts I am sorry, I didn't have time to review the entire post.

User avatar
gdurkee
Founding Member
Posts: 763
Joined: Tue Nov 08, 2005 8:20 pm
Experience: N/A

Ribbeting

Post by gdurkee » Sat Oct 27, 2007 12:25 pm

For the whole Sierra, I don't really know how many total lakes might be netted to restore frog habitat. If I had to guess, I'd say no more than something in the low 100s (i.e. 120 +/-) over the next 30 years. I want to emphasize that's a major guess and applies to the Sierra between Tahoe and just south of Whitney. Elsewhere I said that you need some sort of barrier to prevent the fish from returning (small waterfall, at least). You also need more than just one suitable lake. Ideally you need a basin with a number of small lake cirques so there's diverse population and habitat.

In a post on the fish forum, Caddis asked why, if there's one healthy frog population, other nearby lakes have to be restored ("fish killed off") as well. The fact that frogs had become so isolated is why their population has likely crashed. Previously if, say, chytrid had hit a population and wiped them out, the population would recover once the disease died away and other frogs repopulated from as far as a few miles away -- but in the same basin connected by streams. When fish are in the intervening streams and lakes, that doesn't happen. Or, worse, if there was only one lake with frogs remaining, that was it for the whole basin. So the idea is to try to restore a number of lakes. This may be proving correct as a model. Chytrid recently got into 60 Lakes Basin where a number of lakes have been restored. It almost totally wiped out one chain of lakes. The hope is that nearby frogs get back to that lake.


The first round of habitat restoration of lakes was done (in Sequoia Kings) as a proof of concept experiment. I think it consists of only 8 lakes or so -- total. I don't know what other agencies are doing, but NPS in Sequoia Kings is writing an Environmental Assessment for the next round of habitat restoration. A public notice was given that the process had started and some comments have come in.

The next stage is when the EA is released for public comment on the specifics of the plan. I do know that the biologists involved are being careful to, wherever possible, avoid lakes that are known to be popular fishing holes. To get on the mailing/notification list, write the Sequoia Kings Superintendent and tell them you want to be notified when the plan is released. Then you can read it and comment.

Check with Yosemite and California Dept. of Fish and Game to see how they're proceeding with future restoration.

Next: regarding ducks or other birds maybe getting caught in gill nets. I wrote Vance Vredenburg, who's been doing gill netting in 60 lakes basin for the last 10+ years. Vance is now Assistant Professor of Biology at San Francisco State. His reply:
I've never had a bird get caught in my gill nets, but that isn't to say it would never happen. If the nets are set correctly they should be 100% underwater so a duck should be fine. More aquatic birds like Dippers may be more in danger as they spend much more time zooming around underwater. I've seen a lot of those guys but luckily never in my nets.
Next, Next: I've never seen a bear try to catch fish. Also never heard of bobcat or other predator do so. I have seen Coyote attempt to fish, but suspect it's not a huge part of their diet. Bear do, though, catch frogs.

So I guess the short answer is you can definitely have both fish and frogs -- and that's definitely the intent of management to do so. In spite of what some people here imply, I don't see that changing (I base that on almost 40 years with the park service). As important, it would be so difficult as to be impossible to eliminate fish from any significant percentage of high sierra lakes.

Hope that helps. Ribbet! (also, incidentally, yellow-legged frogs don't go ribbet. They have a high pitched squeak. Very weird).

g.

Post Reply

Who is online

Users browsing this forum: Bing [Bot], Google Adsense [Bot] and 2 guests