Repost from the old site.
I don’t write much about amphibians on here, but I am amphibian nut, in addition to being a mammal, reptile and bird nut. I would be a plant and insect nut too if I could only figure out how to identify them. I’m interested in fish, but they are a little harder to observe in the wild unless they are at the end of your hook.
Anyway, I have long taken an interest in amphibians here in California and to a much lesser extent, throughout the entire West. I am particularly interested in threatened and endangered amphibians here in the state.
The mountain yellow-legged frog has declined disastrously here in the state, starting with heavy fish stocking in the Sierras by pack mules, and then declining wildly with arial stocking of high country lakes via airplane that began after World War 2. This arial stocking has since proven to be one of the stupidest things that the California Department of Fish and Game has ever done.
Every year, countless fingerlings were dropped into lakes all up and down the Sierras, even though after a while almost all of these lakes had completely self-sustaining populations and many lakes saw few if any fishermen in a given year. Furthermore, the populations grew so high that the fish became stunted and malnourished.
In addition, they caused serious problems to the entire ecosystem of the Sierra. This is because in general, fish were absent from much of the high country in the Sierra. The exception was in the Southern Sierra, where the golden trout was native. In the North, Paiute Cutthroats and Lahontan Cutthroats were native to some streams.
Rainbow trout were present, but mostly at the lower elevations. Apparently the streams were so steep that trout were not able to climb up the rivers and creeks to even get into the high country. When men first came in numbers to the High Sierras in the late 1800’s, they found most waterways devoid of fish.
However, there were vast populations of amphibians, in particular mountain yellow-legged frogs. They were so numerous at many high country lakes that you could almost hardly walk around without almost stepping on them.
Before World War 2, limited fish stocking began in the Sierras. Stocking was done in the high country via mule trains and was not particularly effective. However, the stocking was already starting to cause declines in the mountain yellow-legged frog population.
After WW2, arial stocking began and soon turned into a comedy routine and a massive waste of taxpayer money. The CDFG was addicted to fish stocking in the Sierras and refused to stop it or even study it even when environmental groups demanded that they do so.
CDFG claimed that the fish stocking program was somehow exempt from CEQA, California’s landmark environmental law and probably the one law that California’s business class hates more than anything else. Business interests have been trying to get rid of CEQA for decades now, but it’s not going anywhere.
The reason environmental groups wanted the stocking stopped was because studies began to show that fish were having a devastating effect on the mountain yellow-legged frog (MYLF) populations. This is because the MYLF did not evolve in the presence of fish and hence had adopted no defenses against them. Wherever fish were present, MYLF was either not present or there in only reduced numbers.
The fact that CDFG dragged their heels on protecting the MYLF for ages shows that CDFG hardly has an environmentalist agenda at all. They almost never propose any species for threatened or endangered (T & E) status anymore, and usually reject almost all petitions by environmental groups to list anything. They hardly protect anything once it does get listed anyway, so one wonders what good the listing even does.
The CDFG screams that budget cuts means they can’t do anything at all, and another problem is that much of their budget is funded out of fishing and hunting licenses. I have met quite a few individual biologists who work for the agency and by and large they are good folks. I think that there are political appointees at the top that thwart just about anything reasonable getting done though.
It’s not well understood that California is not really a very liberal state in many ways. The voters are still mostly White and older and they are much more conservative than the population as a whole.
Despite blatherings by White Nationalists that Euro Whites are the only race that bother to protect any nonhuman life that lacks utilitarian use for man, since 1980 and US Whites voting rightwing, there has been no greater enemy of the environment and nonhuman life in the US than Whites.
These Whites have solidly supported a pro-business and pro-corporate agenda that has declared war on the environment and every living thing in it. If we let capitalists have their way, they will exterminate all nonutilitarian nonhuman life on this planet, all because those living things get in the way of making a buck.
Hence we have a state run by Republican Arnold Schwarzenegger that is almost totally beholden to corporate and business interests. This has been the case for every California governor since Jerry Brown.
Anyway, various hypotheses have been proposed for the decline of the MYLF. The non-native fish hypothesis has born out well. Pesticides from the Central Valley drifting up the mountains have also been suspected in the decline, along with the ozone hole.
There is some evidence that pesticides are related to MYLF declines, but testing the ozone hole hypothesis has shown that a thinning ozone layer is not frying frog eggs, even at high elevations. However, the thinning ozone layer has been having a bad effect on other frog and toad species. It seems that different species are variably effected by the thinning ozone layer.
Another hypothesis has been that a fungus called chytrid has been killing MYLF’s. This seems to be the case, and the killings are accelerating. Chytrid has been devastating frog and toad populations in various distant parts of the world, especially North, Central and South America and Australia.
An article was recently published in the journal Nature claiming that global warming was causing chytrid to spread. However, a subsequent article was published in another journal that seemed to indicate that global warming had not been proven to be behind chytrid’s spread. A cautious analysis seems to indicate that neither side has proven its case yet.
This particular type of chytrid seems to have escaped from a lab in Australia and has since been devastating frog and toad populations. First it pounded populations in Australia, then it moved to the Americas. Frogs and toads may not have evolved with this fungus, so it’s been hammering them hard. If any frogs and toads can survive the fungus, they may be able to pass on an immunity to it and enable the species to survive.
There have been widespread chytrid outbreaks in the Sierras in recent years. Just when some recent efforts to eliminate fish from some national park waters in the Sierra seemed to be bearing fruit, the fungus has been nailing the MYLF but hard. There have been 25-30% reductions of all types of frog populations in the Sierra over the past five years due to the fungus.
One theory is that the fungus has always been there but that recent environmental changes such as industrial and agricultural contaminants in the air, the frogs’ immune systems have been compromised, making them susceptible to the fungus.
However, some populations get hit very hard by the fungus for a while and then bounce back. The theory is that they have some sort of genetic resistance to the fungus. If this is true, then maybe the MYLF can survive in the Sierra after all.
As usual, the Bush Administration, the most anti-environmental President in recent history, refused to list the MYLF although it has been petitioned repeatedly. The most recent designation is “warranted but precluded “.
This is a sickening game that the Fish and Wildlife Service has been playing for some time now, dating back the “liberal” Clinton Era. The game says that the species qualifies for listing, but there are no funds to list it. It’s just a despicable bureaucratic game. How much does it cost to publish a listing notice in the Federal Register? Very little.
At the same time that the Administration pricks whine that there is no money to list any new species, they cynically and dishonestly cut the budget for listing new species! “Liberal” Bill Clinton started this bullshit, but Bush took it to overdrive. Sometimes, there is no lower life form than a politician.
Anyway, there are all sorts of species sitting on this idiotic warranted but precluded crap list for ages now. As the MYLF has declined by 93.3% in the last 100 years, that’s an endangered listing right there, and I’m not even a biologist. I know the listing criteria.
The Southern California population, which may be a separate species, is virtually extinct. It has declined by 99%. The Bush Administration did list this frog, but it’s almost gone anyway, as there are only 79 frogs left.
Probably no man has done more to save the MYLF than Roland Knapp, a Research Biologist at the University of California Sierra Nevada Aquatic Research Laboratory.
These guys associated with universities are usually pretty honest and non-corrupted, while the fisheries and wildlife biologists and botanists I met working for the local National Forest were some of the most awful, corrupted and dishonest people I have ever met. If you don’t care about species and whether they go extinct or not, don’t take a job with the feds dedicated to protecting them.
The local national forest, the Sierra National Forest, is doing absolutely nothing to my knowledge to protect MYLF and MYLF is almost gone from Sierra National Forests anyway. Truth is that even USFS wildlife and fisheries biologists are ecstatic if a rare species of extirpated or nearly extirpated from their forest. Now we don’t have to save it! Less paperwork! I’m not kidding.
It was Knapp’s research a while back that conclusively proved that it was nonnative fish that were driving the MYLF extinct.
Fishermen are understandably upset about fish removal projects in the Sierras. To date, these projects have been very limited. It is probable that the main reason that the Feds are not listing the frog is that a listing would mandate fish removal from many or most Sierra waters. Those fish were not even there to begin with, and the MYLF is only present at high elevations anyway. There are plenty of low elevations to fish in.
I’ve done fishing in the High Sierras myself, but if you are so shallow that you can’t hike into the High Sierras and just dig it for what it is without wetting a line, I don’t even think you should even be back there.
Even better, fish removal would probably reduce the number of humans in the backcountry. It’s mostly wilderness anyway, so why do we need tons of people back there? They can remove the fish from most of those waters for all I care. If there are no fish in the lakes, just bring a book or lie on your back or explore around all day.
Recent research indicates that there are three separate genetic units of the MYLF in the Sierras, a Northern, Central and Southern genetic unit. At present, these have been split off into a new species, the Sierra Yellow-Legged Frog , or Rana Sierrae.
The Southern California population and some southern Sierra populations have been split into a whole new species, the Southern Mountain Yellow-Legged Frog. Distribution maps for Rana Sierrae and Rana Muscosa. Rationale for the split. The two species are estimated to have split 2.4 million (!) years ago. Hence, the Mountain Yellow-Legged Frog, the subject of this post, no longer exists in its former form.
This split was done on the basis of an article last year (Vredenburg et al 2007). Whether the three separate genetic clades of the Sierra Yellow-Legged Frog warrant splits into subspecies has not yet been determined. In order to split into subspecies, usually a certain X genetic distance must be shown.
In February of this year, the Center for Biological Diversity petitioned again to list Rana Sierrae as endangered. Surely it qualifies.
Lots of cool frog, tadpole and terrain photos at the links.
- Lips, Karen R., Diffendorfer, Jay, Mendelson III, Joseph R., Sears, Michael W. 2008. Riding the Wave: Reconciling the Roles of Disease and Climate Change in Amphibian Declines. PLoS Biology Vol. 6, No. 3.Pounds JA, Bustamante MR, Coloma LA, Consuegra JA, Fogden MPL, et al. 2006. Widespread Amphibian Extinctions From Epidemic Disease Driven by Global Warming. Nature 39: 161–167.
Vredenburg, V. T., R. Bingham, R. Knapp, J. A. T. Morgan, C. Moritz, and D. Wake. 2007. Concordant Molecular And Phenotypic Data Delineate New Taxonomy And Conservation Priorities For The Endangered Mountain Yellow-Legged Frog. Journal of Zoology 271:361-374.