December 6, 2009

New Book on Global Amphibian Declines

Jim Collins and Martha Crump recently published a new book entitled, "Extinction in Our Times: Global Amphibian Decline". This is a complex subject and by all accounts the authors do a great job of synthesizing this material for the scientifically-inclined as well as for more general audiences. Joe Mendelson, a scientist at the Atlanta Zoo and one of the key players in the Amphibian Ark project, posted this review on book's Amazon web page

The authors have accomplished something spectacular here. They have taken a very disturbing and complex story---that has its share of intertwined controversies, to be sure---and assembled a remarkably objective and even-handed summary. The book doesn't foolishly proclaim to have solved all the mysteries, nor offer a silver-bullet panacea for the amphibian crisis. Rather it presents a fully readable retrospective and current review of the crisis of amphibian declines and extinctions and an interesting perspective on how science as a process, and the scientists as people, responded to an unprecedented set of circumstances. The authors do an especially good job at maintaining full objectivity in the face of ongoing controversies and disagreements among scientists. Similarly, to treat fairly the scientists and hypotheses that time has shown to have been "wrong"---or, better said, the ideas and conclusions that are not supported by all of the accumulated data. The nice style adopted by the authors throughout the book is to simply point out which hypotheses are the best supported by the data. There are no "winners" or "losers" among the people and ideas presented in this book, as the authors imply that all contributions to the amphibian crisis have been important.

We have a long way to go in understanding and confronting the ecological catastrophe of global amphibian declines and extinctions. But this book is a complete summary of where we've been and where we are positioned today in this phenomenon. Importantly, the authors also pay especial attention to how we got to our current position of knowledge and conservation action. This aspect of the book makes for a fascinating study of how a completely unorganized cohort of scientists responded when the found themselves suddenly in the face of an overwhelming conservation challenge. In retrospect, the scientists responded quite slowly. But after reading this book, you will realize that no other response was possible.

I hope this book is read carefully by scientists, conservationists, and policymakers working on other aspects of the global environmental crisis. This case study of the amphibian crisis offers many lessons applicable to other biodiversity crises, be it fungal infections in bats or die-offs of coral reefs. The book also offers a complete overview of the phenomenon of amphibian extinctions. I wish all reporters and science writers covering the subject would give this a careful read before beginning their stories! Kudos to the authors for a remarkable and easily absorbable synthesis of a very complex story.

So, if you want to learn the latest about one of the most profound extinction events in recorded history, this book should fit the bill.

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November 24, 2009

Fish Stocking EIR/EIS - Part 5

Anybody who read the California Department of Fish and Game (CDFG) draft fish stocking EIR-EIS knows that this document is badly flawed. Many of these flaws, such as an inadequate range of alternatives, are fundamental to the entire document and addressing them would require a major rewrite of the EIR-EIS. However, the court-ordered deadline for the final EIR-EIS is January 11, 2010. How is the CDFG going to make all the necessary changes to this document in time to meet this deadline?

One possibility would be that the CDFG could go back to the Court and request a deadline extension. However, the CDFG is apparently determined to meet the original January 11 deadline, so I'm guessing that instead we will see a final EIR-EIS that is only marginally improved from the draft version. That will undoubtedly result in another lawsuit, and given that the same CDFG legal counsel who lost the previous fish stocking lawsuit will be providing advice again this time around, the CDFG will lose again and will be forced to make the necessary major revisions to the EIR-EIS that many people have been calling for all along.

The inadequacy of the current draft EIR-EIS and all the shenanigans that are likely to follow could have been avoided if the CDFG had decided from the very beginning of this process to thoroughly and honestly evaluate the environmental costs and benefits of their fish stocking program. Instead the CDFG did what they usually do on this issue, which was to first decide what the document's conclusion would be (i.e., continue the current fish stocking program), and then use every imaginable argument to justify this conclusion, no matter how ridiculous these arguments are. When this process has finally run its course, I suspect that the CDFG would have spent much less money, done a better job of protecting native species, and produced better recreational fisheries if they had used the CEQA process the way it was intended.

And this from an agency whose stated mission is "to manage California's diverse fish, wildlife, and plant resources, and the habitats upon which they depend, for their ecological values and for their use and enjoyment by the public". If only the CDFG would take their stated mission seriously....

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November 11, 2009

Fish Stocking EIR/EIS - Part 4

The DFG trout stocking program currently introduces millions of fingerling, sub-catchable, and catchable trout into lakes and streams throughout California with the goal of improving existing fisheries. In addition to stocked trout, recipient habitats typically also harbor native trout populations or established non-native populations, with the latter having become established following earlier stocking efforts (both are referred to here as “resident” populations). In light of the fact that numerous studies have indicated that trout stocking has the potential to impact these resident trout populations and thereby negatively affect fishery quality it is ironic that the EIR-EIS fails to analyze stocking impacts on recreational trout fisheries.

The court order required the DFG to analyze the environmental impacts of the current stocking program and it is difficult to conceive of such an analysis not including an assessment of impacts of stocking on resident trout fisheries. In the EIR-EIS, this analysis is restricted solely to the effects of trout stocking on a few special-status native trout species (e.g., golden trout). Such a narrow interpretation of "environmental impacts" is unacceptable. As the following discussion makes clear, the potential exists for the current trout stocking program to seriously impact resident trout populations and adversely affect recreational fishing opportunities. These impacts should be analyzed and disclosed.

In an overview paragraph describing the effects of stocked trout on other salmonids the EIR-EIS (page 4-66) states,

“Most hatchery rainbow trout that are stocked for put-and-take fisheries in streams are caught within 2 weeks of planting (Butler and Borgeson 1965; Moyle 2002), and the remainder likely die of starvation or stress within a few weeks (Moyle 2002). Therefore, the potential for impacts on native trout species through competition and predation associated with catchable-sized rainbow trout plantings in streams appears to be low.... Catchable-sized hatchery rainbow trout released into lakes survive for longer periods than stream stocked fish because of lower energy costs associated with the absence of stream currents, and a relatively lower vulnerability to angling and predation (Moyle 2002). Therefore, the duration of competitive and predatory impacts on native lake populations following stocking of catchable-sized trout should be greater than the impacts following stream stocking.”
A less selective presentation of the available scientific literature would clearly indicate that the introduction of hatchery trout can negatively impact resident trout in both streams and lakes. In streams, direct effects are well-documented and usually result from competition between stocked and resident trout. This competition can produce slower growth rates (Weiss and Schmutz 1999, Bohlin et al. 2002), increased movement (Vincent 1987), and increased mortality of resident trout (Petrosky and Bjornn 1988, Baer and Brinker 2008). In addition, stocking catchable trout can increase fishing effort and in turn increase capture and removal rates of resident trout (Baer et al. 2007). These effects can subsequently result in lower overall trout densities (Vincent 1987).

The study by Vincent (1987) provides a particularly detailed description of the consequences of stocking hatchery trout into rivers and streams that contain resident trout populations. In this study, the long-term stocking of hatchery trout into the heavily-fished Varney section of the Madison River was halted and concurrently an unstocked tributary (O’Dell Creek) began receiving plants of hatchery trout. After four years of no stocking in the Varley section, the number and biomass of 2-year-old and older resident brown trout increased by 160%. Resident rainbow trout numbers increased by 800% and biomass increased by 1000%. In contrast, three consecutive years of hatchery trout stocking into O’Dell Creek resulted in a 49% reduction in the numbers and biomass of 2-year-old and older resident brown trout. The obvious conclusion from this study is that the stocking of hatchery trout can have dramatic impacts on resident trout populations and can in some cases actually decrease the quality of trout fisheries. As a result of the Vincent (1987) study, the State of Montana eliminated all stocking of flowing waters and restricted stocking only to lakes and reservoirs.

Impacts from stocking trout into lakes that contain resident trout are more poorly understood than impacts in flowing waters. However, two studies provide important insights. Elser et al. (1995) studied the consequences of halting rainbow trout stocking in Castle Lake, a historically fishless lake in northern California that at the time of the experiment contained introduced rainbow trout and brook trout. The brook trout population was capable of natural reproduction in Castle Lake but the rainbow trout population was maintained entirely by stocking. When rainbow trout stocking was halted, brook trout recruitment increased. Three years after rainbow trout stocking was halted, total trout numbers had increased by 20% (previous dominance by rainbow trout now replaced with dominance by brook trout) and total trout biomass had increased by 30%. In the Sierra Nevada,  Armstrong and Knapp (2004) compared trout densities and growth rates in 61 alpine lakes before and after a 4-8 year period of no fish stocking ("stocking-termination" lakes), and also between the stocking-termination lakes and control lakes that continued to be stocked. Contrary to the expectation that Oncorhynchus species stocked into alpine lakes rarely establish reproducing populations, results indicated that 70% of the stocking-termination lakes actually contained reproducing trout populations. For these reproducing populations, 4-8 years of no stocking resulted in no detectable change in trout density and may have resulted in increased trout growth rates in some lakes.
Therefore, as in flowing waters the stocking of hatchery trout into lakes can actually reduce total trout numbers and biomass, with negative consequences for fishery quality.

In summary, the results from these and many other studies lead one to the unavoidable conclusion that in at least some situations no stocking will actually result in better fisheries than intensive (and expensive) fish stocking. Given the potential severity of fish stocking impacts on resident trout populations and trout fisheries (and the associated costs), it is clear that the EIR-EIS must provide a thorough analysis of these impacts. 

Armstrong, T. W. and R. A. Knapp. 2004. Response by trout populations in alpine lakes to an experimental halt to stocking. Canadian Journal of Fisheries and Aquatic Sciences 61:2025–2037.

Baer, J., K. Blasel, and M. Diekmann. 2007. Benefits of repeated stocking with adult, hatchery-reared brown trout, Salmo trutta, to recreational fisheries? Fisheries Management and Ecology 14:51-60.

Baer, J. and A. Brinker. 2008. Are growth and recapture of hatchery-reared and resident brown trout (Salmo trutta L.) density dependent after stocking? Ecology of Freshwater Fish 17:455-464.

Bohlin, T., J. I. Johnsson, and J. Pettersson. 2002. Density-dependent growth in brown trout: effects of introducing wild and hatchery fish. Journal of Animal Ecology 71:683-692.

Elser, J. J., C. Luecke, M. T. Brett, and C. R. Goldman. 1995. Effects of food web compensation after manipulation of rainbow trout in an oligotrophic lake. Ecology 76:52-69.

Petrosky, C. E. and T. C. Bjornn. 1988. Response of wild rainbow (Salmo gairdneri) and cutthroat trout (S. clarki) to stocked rainbow trout in fertile and infertile streams. Canadian Journal of Fisheries and Aquatic Sciences 45:2087-2105.

Vincent, E. R. 1987. Effects of stocking catchable-size hatchery rainbow trout on two wild trout species in the Madison River and O'Dell Creek, Montana. North American Journal of Fisheries Management 7:91-105.

Weiss, S. and S. Schmutz. 1999. Response of resident brown trout, Salmo trutta L., and rainbow trout, Oncorhynchus mykiss (Walbaum), to the stocking of hatchery-reared brown trout. Fisheries Management and Ecology 6:365-375.

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November 8, 2009

Fish Stocking EIR/EIS - Part 3

In this post I'll focus on one of the most serious shortcomings of the EIR-EIS: the method used to evaluate the impacts of the current stocking program. In most CEQA documents the environmental impact of a new project is judged by comparing environmental conditions expected under the new project against the current environmental conditions (i.e., without the project). Applying this approach to the current CEQA fish stocking analysis would suggest that impacts of the current fish stocking program would be judged relative to those under a "no stocking" alternative. Paradoxically, the EIR-EIS assesses impacts by comparing those caused by fish stocking in the period 2004-2008 (the "baseline") against impacts caused by previous stocking. As stated on page 1-3,
"DFG’s intent in this EIR/EIS is to analyze the environmental effects of a number of specific programs it currently manages that surround the rearing and stocking of a specific set of fish species. The whole of these individual programs is referred to as “the Program” in subsequent chapters, and serves as the baseline and No Action alternative as defined by CEQA. The detailed analysis of the current condition or baseline, as contained in Chapters 3–6, is not typical for CEQA or NEPA, which usually analyze a proposed project or proposed action. However, the court order that directed preparation of this EIR/EIS mandated that DFG analyze its current fish stocking program."
Under this analysis approach, as long as the impacts that occurred during the 2004-2008 baseline were similar in magnitude to those that occurred during previous stocking the impact of the current stocking would be deemed "non-significant". This conclusion regarding impact significance would be unchanged even if the impacts of the 2004-2008 stocking and previous stocking were both severe.

That this twisted logic produces scientifically unsupportable assessments of impact is hardly surprising. One example relates to the assessment of trout stocking impacts on the long-toed salamander (Ambystoma macrodactylum). In California, this species was historically widely distributed in the Sierra Nevada, Klamath Mountains, and Cascade Mountains where it inhabited a wide variety of perennial fishless ponds and lakes. Several recent studies have reported that A. macrodactylum is typically eliminated from these habitats following trout introductions and this species is clearly much less common in California today than it was historically. Similarly severe impacts of stocked trout on A. macrodactylum have been reported from elsewhere in the western U.S. Despite these well-documented impacts of stocked trout, the EIR-EIS concludes the following (page 4-76):
"Although historic trout stocking likely resulted in a geographically widespread extirpation of long-toed salamander populations from high mountain lakes in the Sierra Nevada, Cascade and Klamath mountain ranges, the continuing conduct of the trout-stocking program during the 2004-2008 baseline period has likely not resulted in any further population changes that would constitute a significant impact on the long-toed salamander. Thus the impact of the trout stocking program is less than significant."
In light of well-established impacts of stocked trout on A. macrodactylum, this finding of non-significance is untenable. Unfortunately, the EIR-EIS is replete with many other scientifically indefensible conclusions that are a consequence of the flawed methods used in these impact analyses. The only way to thoroughly analyze the impacts caused by the current stocking program is to compare those impacts against the impacts that would occur with no stocking.

In my next post I'll focus on the failure of the EIR-EIS to analyze the impacts of the current stocking program on resident trout fisheries. To give people time to read this post before comments to the DFG are due (November 16), I'll move my next post up from November 16 to the middle of this week.

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November 2, 2009

Fish Stocking EIR/EIS - Part 2

Last week I mentioned that in my next post I'd write about the flawed evaluation of fish stocking impacts in the California Department of Fish and Game (CDFG) draft EIR/EIS. So, here goes. The flawed evaluation derives from two sources: (1) an inadequate range of management alternatives considered, and (2) the use of the last five years of fish stocking as a baseline against which to judge impacts. I'll focus on #1 this week and on #2 next week.

The draft EIR/EIS analyzes three alternatives. These are (1) no project/no action, under which no changes would be made to hatchery operations and stocking programs; (2) continue to operate hatcheries as in the past five years and stock fish based on new guidelines - this is the "preferred alternative"; and (3) permanently operate the hatchery and stocking program as directed in the interim court order, under which no stocking would occur where any of 25 sensitive native species occur or where surveys for these species have not been conducted. Given that the "new guidelines" proposed in the EIR/EIS for the preferred alternative (#2 above) are minor mitigation measures at best, these three alternatives represent an unnecessarily narrow range of alternatives and none would result in a substantive change in the current fish stocking program. This failure to analyze a broader range of alternatives is very unfortunate because it means that the CDFG is missing a chance to change its fish stocking program in ways that would benefit native species
AND recreational fisheries. An alternative that seems an obvious one to have been included in the analysis is one that proposes halting stocking in flowing waters and refocusing the stocking program on less sensitive habitats such as artificial impoundments. No such luck.

On page 7-6 of the EIR/EIS it is mentioned that the termination of stocking in flowing waters was considered as an alternative but it was eliminated from further analysis. The rationale for its elimination was as follows: "The alternative was suggested as patterned after a similar practice followed by the State of Montana regarding its stocking guidelines. Demand for recreational fishing in flowing waters is far greater in California than in Montana. Eliminating stocking altogether in flowing waters would place considerable pressure on native and wild stocks that already exist in flowing waters and would eliminate a large proportion of the recreational fishing opportunities for anglers that wish to camp and fish along waters in California." This rationale is absurd.

The state of Montana stopped stocking all flowing waters based on studies that showed that this stocking was having such serious impacts on resident trout that the net result of stocking flowing waters was a dramatic reduction in trout numbers. The termination of stocking resulted in similarly dramatic increases in the number of trout present. These studies (summarized here) were conducted, in part, on the Madison River which is one of the most heavily fished rivers in Montana. So, for the CDFG to argue that they have to continue stocking flowing waters because of high angler pressure makes absolutely no sense when stocking could in fact be harming these fisheries. Once again the CDFGs working assumption is that stocking is the only solution to improving angling opportunities. At the very least, the CDFG should have included an alternative that proposed eliminating stocking in flowing waters and analyzed the alternative in detail.

Some might reasonably wonder why a "no stocking" alternative was not included in the EIR/EIS. For the trout stocking program, the reason appears to be that the CDFG is mandated by recent legislation (AB 7, passed in 2005) to stock a certain number of trout per fishing license sold. In 2009 and subsequent years, the CDFG is required to stock a minimum of 2.75 pounds of trout per fishing license sold in 2008, 2.0 pounds of which must be of catchable size or larger. The portion of the California Fish and Game Code that summarizes these requirements is available here. The fact that this legislation dramatically constrains the range of alternatives that the EIR/EIS could consider is very unfortunate. But there os a deeper irony here. Legislators tried for several years to pass AB 7 and were always stymied by California Trout ("CalTrout"), a fishing organization that opposed the legislation. CalTrout finally threw its support behind the bill after getting language inserted into the draft legislation that allocated two million dollars to CDFGs chronically underfunded Heritage and Wild Trout program. With CalTrout now supporting the legislation,
AB 7 was signed into law. Now a few years later, AB 7 is precluding the EIR/EIS from considering reductions in the number of trout stocked annually, reductions that could actually improve fisheries. I hope the directors of CalTrout are fully aware of the consequences of their support for this screwy legislation.

More next week....

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October 26, 2009

Fish Stocking EIR/EIS - Part 1

As stated in last week's blog post, the California Department of Fish and Game (CDFG) recently released their draft fish stocking EIR/EIS to the public. Comments are due on November 16. When the CDFG was ordered by the court to conduct this environmental analysis I had some hope that the CDFG would use this as an opportunity to fully evaluate their current stocking program and make changes that would benefit native wildlife (e.g., native amphibians and fish) and improve fisheries. Unfortunately, a read of the document's objectives statement indicates that this environmental analysis was largely an effort to justify the current fish stocking program. The objectives statement (page 5) reads, "The fundamental objectives of DFG’s Program are to continue the rearing and stocking of fish from its existing hatchery facilities for the recreational use of anglers, for mitigation of habitat loss attributable to dam construction and blocked access to upstream spawning areas, for mitigation of fish losses caused by operation of the state‐operated Sacramento–San Joaquin River Delta pumps, and for conservation and species restoration."

This objectives statement ignores abundant evidence that the stocking of trout and salmon can actually have negative effects on the resident fishery. For example, stocking of "catchable" trout into streams results in high levels of competition between stocked and resident trout. The end result is often a reduction in the total number of trout present. Similar problems beset stocking of salmon species. Given an abundance of these sorts of findings it is not at all clear that fish stocking is always the preferred means of providing recreational angling opportunities or that stocking can in fact mitigate for habitat loss caused by dams. As such the objectives statement in the EIR/EIS indicates the CDFGs interest in continuing the current stocking program regardless of whether some aspects of that program actually have negative effects on fisheries.

I would have liked to see an objectives statement such as the following: "To provide a stocking program that supports diverse anadromous and inland salmonid fisheries and protects native species and natural resources from adverse impacts from stocking." This statement makes it clear that fish stocking is a management tool that would be used when necessary to improve fisheries. I proposed this objectives statement to the CDFG some months ago but obviously my suggestion fell on deaf ears.

Given the flawed objectives statement upon which the EIR/EIS is based it is little surprise that the environmental analysis supports the continued fish stocking program with few meaningful changes. Next week I'll discuss the CDFGs flawed evaluation of fish stocking impacts.

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October 18, 2009

Another Field Season has Come and Gone

My 2009 summer field season ended in late September. Now weeks later all of the research gear is put away and the data is safely in my lakes database. The summer went largely as expected, with some notable successes and some unanticipated challenges. Below I've provided a summary of what our summer objectives were and what we actually accomplished. But first a sad note....

This summer I lost a close friend and fellow field biologist. On August 30, Jeff Maurer died in a climbing accident while ascending Third Pillar on Mt. Dana. Jeff had worked in Yosemite National Park since 1988, studying Peregrine Falcons, Great Gray Owls, and Northern Goshawks. In 2006 he took on the task of leading Yosemite's new lake restoration program, and in that capacity he directed fish removal efforts in numerous key locations around the Park. These efforts will continue, of course, but Jeff's infectious enthusiasm and unmatched dedication to this restoration effort will be sorely missed. He was truly one-of-a-kind. For stories about Jeff, check out

So, what did we set out to do this summer? Our research team (me, Cherie Briggs, Vance Vredenburg, Erica Rosenblum, and more than a dozen field and laboratory assistants) had two primary objectives. The first objective follows from our field observations that after the arrival of the
amphibian chytrid fungus (Batrachochytrium dendrobatidis - "Bd") at a site most mountain yellow-legged frog populations decline to extinction but a few persist despite the disease, albeit at markedly lower densities. There are several potential explanations for these different disease outcomes, including inherent differences in frog susceptibility to chytridiomycosis (the disease caused by Bd) or differences between Bd strains in their virulence. So this summer we conducted a laboratory experiment to evaluate the relative roles of these two factors in driving different disease outcomes (frog population persistence versus extinction). We hope to wrap up the experiment by December.

Our second objective was to use a field experiment in which mountain yellow-legged frogs are cleared of Bd to determine whether this treatment influences the outcome of Bd epidemics. Frogs were treated with an anti-fungal drug at three lakes in each of two basins located in Kings Canyon National Park. Frog populations in both basins had suffered catastrophic declines in the past four years following the arrival of Bd, and without intervention it is likely that these frog populations would have been extinct within another couple of years. It will be 1-2 years before we have any definitive results but for now, suffice it to say that we were able to significantly reduce Bd loads on frogs in the field and this treatment dramatically improved frog survival. I'm hopeful that such frog treatments may provide us with an important conservation tool in the future, but we still have lots of unanswered questions that need to be addressed. I'll provide further updates as the results come in.

Finally, the California Dept. of Fish and Game (CDFG) released a draft fish stocking EIR/EIS to the public on September 25 (available from the CDFG web site). Comments on the draft document are due to the CDFG by November 16. Given that this document will guide CDFG fish stocking practices for many years I encourage everyone interested in this issue to read the EIR/EIS and provide comments to the CDFG. I'm still working my way through the 8 chapters and 12 appendices but it is clear that there is lots of room for improvement. I'll provide additional details on this document in upcoming blog posts. Stay tuned....

Now that I'm back behind my desk I'll be posting new Frog Blog entries every Monday morning. I hope you find them interesting and informative.

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June 8, 2009

The Field Season has Begun

Today is the first day of my summer field season. I'll be in the field for the majority of the next three months so my posts during this period will come at irregular intervals. I'll do my best to provide periodic updates but they won't be weekly as they are during the non-summer period.

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June 1, 2009

Reforming the California Department of Fish and Game?

When it comes to the management of California's fisheries and native aquatic fauna Tom Stienstra, the writer of the Outdoors column in the San Francisco Chronicle, and I rarely think alike. In his 5/31/09 column, Tom argues that the budget crisis currently enveloping California is an opportunity to reform the Department of Fish and Game (CDFG). Although I certainly agree that the CDFG is badly in need of a major overhaul, Tom's proposed solutions would not accomplish a thing. Tom says:

"In the new budget, the governor proposes to take $30 million out of dedicated funds as a 'loan' to the general fund, likely order an additional cut and tell Fish and Game to deal with it. This could devastate matching federal funds the department receives. There's a better way to conduct business. This is how you fix it: All habitat, conservation and nongame programs should be shifted to the Department of Conservation, which can better allocate priorities. This includes endangered species, non-game management, response to oil spills, toxics, timber review, oversight of pet stores, zoos, live-food animal markets and invasive species, few which Fish and Game does well..... This trimmed-down unit would be renamed the Department of Fishing and Hunting, and pay for itself with license fees, stamps and federal excise taxes on fishing and hunting equipment. The governor could get his dream answered to cut all general fund money to the department. This new 'DFH' would exist to stock trout, improve fishing and create hunting programs, especially for wild hogs."

These proposed reforms make no sense. First, simply transferring a wide range of conservation-related duties from the CDFG to the Department of Conservation would produce no cost savings. With most of the tasks the CDFG is currently responsible for transferred to another agency, the CDFG may in fact be able to finance its slimmed-down operations using non-general fund dollars. However, the general fund dollars previously needed by the CDFG would now be needed by the Department of Conservation. This is a zero-sum game.

Second, the suggestion that all conservation-related CDFG programs be transferred to the Department of Conservation ignores the reality that several of these conservation-related programs exist primarily because of the impacts caused by programs focused specifically on fishing and hunting. For example, the CDFG is currently spending $1.8 million dollars to write an environmental document that discloses the impacts of its fish stocking program and proposes means by which these impacts could be mitigated. Why should the Department of Conservation be in charge of dealing with the messes that the CDFG fish stocking program created? The agency that makes the mess should be in charge of fixing the mess. Furthermore, given the many impacts caused by fish stocking, should efforts to mitigate these impacts be paid for using general fund
(i.e., taxpayer) dollars? It seems to me that these efforts should be paid for using revenues obtained directly from anglers (e.g., from fish licenses).

I don't claim to have any solutions to California's budget problems nor are the CDFGs many anachronistic practices easily reformed. However, I would suggest two important initial steps in the direction of reform. First, the CDFG should reduce its fish stocking program to include only to those elements that actually benefit fishery resources. This would eliminate all stocking of mountain lakes that contain self-sustaining trout populations, stocking of rivers and streams where hatchery trout have negative effects on the native trout, and rivers where the stocking of anadromous species negatively affects the native anadromous species. Second, the CDFG should pay for its catchable trout stocking program solely with revenues generated from a new "Hatchery Trout" stamp on licenses. Under such a program, anglers who fish in areas that are stocked by the CDFG with hatchery trout would need to purchase a hatchery trout stamp for their fishing licenses. Under the current system, all California anglers (many of whom avoid hatchery trout like the plague) unfairly end up subsidizing the hatchery program. It makes far more sense for those anglers who benefit from the hatchery program to support it instead of placing this burden on all anglers.

Such a hatchery trout stamp program might even convince me to dust off my neglected fly rod, buy a California fishing license (without a hatchery trout stamp), and go fish one of my favorite lakes or streams.

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May 26, 2009

Chytridiomycosis in Asia

Of the Earth's amphibian-harboring continents (all but Antarctica), Asia was until recently unique in not yet having been invaded by the amphibian chytrid fungus (Bd). That now seems to be changing quickly. During the last few years ago Bd was reported from Japan, South Korea, and Indonesia, all countries around the periphery of this amphibian-rich continent. In the last few weeks Bd was reported from the Philippines, another country on Asia's edge. For a description of the amphibian fauna of the Philippines, check out Herpwatch Philippines.

Given that elsewhere in the world, including Australia, Central America, and California's Sierra Nevada, Bd spread as a distinct wave it seems likely that these initial occurrences of Bd in Asia represent the first outbreaks in what will become a wave of infections. Given the high amphibian species diversity in Asia and high levels of endemism, the spread of Bd across this continent will almost certainly result in hundreds of species extinctions.

Will we find a way to stop the spread of this disease or will our only role be to describe Asia's amphibian extinctions

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May 18, 2009

Good News and Bad News About Amphibian Diversity

The number of known amphibian species worldwide has risen by approximately 20% during the the past decade thanks to intense research on this group of vertebrates. A total of 6487 amphibian species have been described to date ( That is the good news.

Now here comes the bad news. Based on a study published in 2004 in the journal Science, more than 40% of the world's amphibians are threatened with extinction. Given the current number of amphibian species (6487), that means that more than 2500 amphibian species are in serious decline. However, a study by Vieites and colleagues just published in the Proceedings of the National Academy of Sciences suggests that the number of described amphibian species vastly underestimates the actual number of amphibian species on Earth. That means that far more species are in danger of extinction than previously believed.

Vieites and colleauges used DNA sequences from 2850 amphibian specimens sampled from over 170 localities in Madagascar to show that the current number of described amphibian species
(244) in this biodiversity hotspot represents only about one-half of the actual number of species present (estimated actual number of species is 373-465). Therefore, hundreds of species remain undescribed. Habitats on Madagascar have been badly degraded by deforestation, and the results of the new study suggest that this has caused the extinction of far more species than have so far been documented. Furthermore, to date Madagascar is still free of the amphibian chytrid fungus. When the fungus does invade, it won't be 244 species that are impacted. It will be 373 to 465.

The more we learn the bleaker the prospects seem for conserving even a fraction of the Earth's amphibian biodiversity.

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May 4, 2009

Trout Impacts and Stocking Controversies - Beyond California

Much of the recent research on impacts of trout stocking has focused on aquatic ecosystems in California. However, a research program in Maine is now showing just how pervasive these impacts are. Most of Maine's naturally fishless lakes (and there were thousands of them historically) have now been stocked with numerous fish species, including brook trout, and all indications are that these introductions have had similar effects as those documented in California's Sierra Nevada and elsewhere - the disappearance of amphibians and conspicuous invertebrate taxa. The New York Times ran a story last week that provides an interesting overview of what the Maine research is turning up.

On the opposite coast, the practice of trout stocking continues to cause controversy in North Cascades National Park. This is the only national park in the country in which fish stocking is still allowed, but after many years of debate about the practice and detailed scientific study it appears that trout stocking may be on its way out. A recent Associated Press story provides the details.

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April 27, 2009

Another Disease-caused Frog Conservation Crisis

The mountain chicken, Leptodactylus fallax, is one of the world's largest frogs, with adults sometimes weighing up to one kilogram (>2 lbs). This frog was once common on some Caribbean islands but has been decimated by the amphibian chytrid fungus (Bd). In recent years the frogs were found only on the island of Montserrat, an island that until recently was free of Bd. During the last few weeks, these frog populations have suffered severe Bd outbreaks that have killed many hundreds of animals. To ensure that these frogs are not driven to extinction frogs have been flown to three zoos in Europe where they will be used to start a captive breeding population. For more information, check out this story:

The challenges posed by Bd to the conservation of the world's amphibians would have been unthinkable only a few years ago. This stuff gets more challenging by the day.

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April 21, 2009

Trout Impacts in California's Trinity Alps

When it comes to impacts of introduced trout on aquatic ecosystems, the Sierra Nevada is by far the best-studied such ecosystem in the world. However, an increasing number of studies are now being conducted elsewhere and results from this research make it clear that broad impacts are a common consequence of trout introductions into montane habitats. In recent years, a research group at the Forest Service Redwood Sciences Laboratory in Arcata has published several studies showing that introduced trout have severe impacts on a wide range of aquatic amphibians native to mountains in the Klamath bioregion, including the Cascades frog, Pacific treefrog, and long-toed salamander.

In a study just published in Freshwater Biology, Karen Pope and colleagues extend this past research by focusing on impacts to lake-dwelling invertebrates. Using a replicated whole-lake experiment conducted in the historically fishless Trinity Alps, they described changes over a three-year period in the emergence of aquatic insects from lakes in which (1) trout had never been introduced, (2) stocking of nonnative trout
continued during the study, (3) stocking was suspended, and (4) stocking was halted and trout populations were removed using gill nets. Trout removal caused rapid increases in aquatic insect biomass over the three-year study period. Insect emergence was low in both the stocked lakes and stocking-suspension lakes because trout densities remained relatively high in lakes assigned to these treatments. Therefore, trout introduced into these naturally fishless lakes caused significant reductions in the biomass of native invertebrates and these taxa recovered quickly following trout removal.

The focus of the study by Pope and colleagues on insect emergence helps to emphasize a key point which is that trout impacts on lake-dwelling invertebrate communities aren't likely to be restricted to the lakes themselves. Adult forms of aquatic insects emerge from lakes and become available to a wide range of terrestrial predators and scavengers, including reptiles, birds, bats, and ants. Therefore, the
reductions in insect emergence due to trout introductions could impact terrestrial species and the functioning of terrestrial ecosystems. Our increasing understanding of the connections between aquatic ecosystems and the adjacent terrestrial ecosystems is a fascinating area of study and provides a more complete picture of how pervasive the effects of trout introductions can be.

For additional information on the impacts of introduced trout on amphibians in the Klamath bioregion, check out the following papers:

Welsh, H. H., K. L. Pope, and D. Boiano. 2006. Sub-alpine amphibian distributions related to species palatability to non-native salmonids in the Klamath mountains of northern California. Diversity and Distributions 12:298-309 [link].

Pope, K. L. 2008. Assessing changes in amphibian population dynamics following experimental manipulations of introduced fish. Conservation Biology 22:1572-1581 [link].

Pope, K. L., J. M. Garwood, H. H. Welsh Jr, and S. P. Lawler. 2008. Evidence of indirect impacts of introduced trout on native amphibians via facilitation of a shared predator. Biological Conservation 141:1321-1331

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April 14, 2009

Trout Impacts on Yosemite Streams

Most research on the impacts of nonnative trout on aquatic habitats in the Sierra Nevada have focused on lakes, in part because these are the habitats favored by the declining mountain yellow-legged frog. This research has shown dramatic changes to vertebrate and invertebrate species composition caused by trout predation on the larger, more conspicuous taxa. Trout also alter nutrient cycling in these lake habitats as a consequence of the changes in species composition.

A study
by Dave Herbst and colleagues, just published in Freshwater Biology, shows very clearly that impacts of introduced trout on Sierran streams are similar to those documented for lakes. Herbst et al. compared the invertebrate communities, algal cover, and algal biomass in 21 paired streams in Yosemite National Park, one stream of each pair containing introduced trout and the other member of the pair remaining in a natural fishless condition. Densities of 10 out of 50 common invertebrate taxa were significantly reduced in the trout-containing compared to the troutless streams, and these taxa tended to be conspicuous forms whose native habitats are primarily at high elevation above the original range of trout.

Reductions in species richness in the trout-containing streams caused significant increases in algal cover and biomass compared to levels in troutless streams.
Increases in algae are likely a consequence of grazing invertebrates being reduced in the presence of trout and consequent reductions in herbivory.
These indirect effects (trout reduce the density of grazing insects, reduction in grazers causes an increase in algal biomass) are in agreement with numerous other studies conducted on the effects of trout on streams all around the world.

The findings of this study serve as yet another example of the considerable impacts of trout introductions on Sierra Nevada aquatic ecosystems. Given the almost complete absence of watersheds anywhere in the Sierra Nevada that haven't been stocked with trout, it is clear that we need to think about how to restore at least some entire watersheds to their historic fishless condition. That is no small undertaking.

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April 6, 2009

Amphibian Decline Movie - Sadness and Hope

I watched the film, "Frogs: The Thin Green Line", last night. Filmmaker Allison Argo and her team did an amazing job of bringing the amphibian decline issue to a general audience. Despite how dire the situation is I was left with a feeling of hope that collectively we just might make a difference. As usual, time will tell.... The film can now be viewed online on the PBS web site.

As I mentioned recently on The Mountain Yellow-legged Frog Site, the April issue of Fly Rod & Reel magazine has an article by renowned conservation writer, Ted Williams, on the lawsuit over fish stocking in California that was recently won by the Center for Biological Diversity and the Pacific Rivers Council. This is far and away the best article written so far on this issue. I've been hoping that this article would soon be posted on the Fly Rod & Reel web site, but that hasn't happened yet. So, here is a scanned copy of the article (PDF). Additional details on this topic are available on the California Department of Fish and Game web site and in my 4/18/08 and 11/21/08 Frog Blog posts.

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March 30, 2009

Global Amphibian Declines - The Movie

During the past year filmmaker Allison Argo and her team have been traveling around the world to film declining amphibians and find out from scientists what can being done about it. In addition to filming in Panama and the southeastern U.S., Allison's team also spent a few days with my research group while we conducted research on Sierra Nevada yellow-legged frogs in Yosemite National Park. The resulting film, "Frogs: The Thin Green Line" will be shown for the first time on April 5 (this Sunday) on PBS. Allison's previous films on amphibian declines (The Last Frog), declining shorebirds (Crash: A Tale of Two Species), and other wildlife-related topics were extraordinarily good, so I suspect that this latest film will be well worth watching. Hopefully Allison didn't include the footage of me falling into the pond.... On 3/31,the film's creators posted a podcast from "behind the scenes". Check it out.

If you do watch the film, feel free to post your reviews and thoughts here.

Now to the task of finding a friend who owns a TV....

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March 23, 2009

New National Geographic Story on Amphibian Declines

Writer Jennifer Holland and photographer Joel Sartore have created a masterful story on the global amphibian decline phenomenon, just published in National Geographic magazine. The situation surrounding the mountain yellow-legged frog is described in the story, and Joel's photographs of live and dead Rana muscosa from Sixty Lake Basin bring this animal's plight into a sad focus. Check it out.

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March 16, 2009

Anybody Have a Spare Pond?

The ongoing severe declines of mountain yellow-legged frogs in the Sierra Nevada make it all but inevitable that these populations will eventually be listed under the federal Endangered Species Act. Such a listing will trigger the writing of recovery plans for Rana sierrae and Rana muscosa, plans that will undoubtedly call for the development of captive breeding programs. If successful such programs could provide frogs for reintroductions back into the wild and for experiments that are critical to our understanding of important issues related to frog conservation.

As I've discussed in previous posts captive breeding has an increasingly important role to play in species conservation programs but because maintaining frogs in artificial environments (e.g., indoor aquaria in zoos) is very labor intensive (think of the time required to feed 100 frogs every day, change their water, and clean their enclosures), this gets expensive in a hurry. A cheaper and potentially more productive route would be to hold frogs in natural or semi-natural ponds outdoors. This would greatly reduce the resources needed to maintain these populations because the frogs could feed themselves. All we need are some ponds that would provide suitable habitat for mountain yellow-legged frogs. Ideal ponds would be located at elevations above 6000', be deep enough to allow frogs to overwinter (>10 feet), and have reasonable access. Ponds would also need to be surrounded with a frog-proof barrier to ensure that frogs don't wander off.

If we can't locate such ponds we need to consider constructing them. As I write this I'm staring out the window at my back yard, wondering if maybe we could replace that useless lawn with a frog pond. But seriously, we need to engage any interested agency or member of the public and provide the resources necessary to make this happen. Might there be a national forest ranger district out there with a pond near a district office that could be turned into a frog pond? Are there any private landowners who might be willing to have one of their ponds put to such a use?

If any of you readers have any ideas I'd love to hear them.

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March 10, 2009

One Fewer Frog in the Forest

Research by Karen Lips and others on amphibian declines in Central America has made clear that the scope of these declines is unprecedented in modern times. In recent years dozens and perhaps hundreds of Central American amphibian species are thought to have been driven to extinction by the amphibian chytrid fungus. The following article provides a glimpse at one of those amphibians, the Panamanian golden frog. This species is a national icon in Panama but is now believed to be extinct in the wild (link). The only individuals still in existence are those housed in a captive breeding facility in Central America. For additional information about this iconic species, check out

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March 3, 2009

Once Upon a Time....

I remember with crystal clarity the day I realized the impact that the amphibian chytrid fungus (Batrachochytrium dendrobatidis - Bd) was having on mountain yellow-legged frogs in the Sierra Nevada. It was July 2000 and my field crew and I were surveying lakes and ponds along the Monarch Divide and Cirque Crest for amphibians and fish. I'd been as excited as a little kid to get into this area and see some of the most remote lakes in the Sierra, places where several years earlier a backcountry ranger had made observations of many mountain yellow-legged frog populations. When the trip was over 20 days later I felt like I'd been hit over the head with a hammer. The future of frog restoration in the Sierra Nevada had just gotten a lot more complicated than I ever imagined it would be.

Up until that trip the available data on Bd and its impacts was still sparse and remained an abstraction to me. The observations made by Dave Bradford 20 years earlier of frog die-offs in western Sequoia National Park were worrisome but were surrounded by enough uncertainty regarding the cause that I wasn't paying those observations much attention. Afterall, for the past five years I'd surveyed hundreds of lakes and the effects of fish were as clearcut as could be. But there were a few lakes that I'd run across during all of those surveys that did give me pause. There were those lakes near Pavilion Dome that contained fabulous frog habitat but in which I found either no frogs or only the decaying carcasses of frogs that had died the previous winter. And that lake between Lake Basin and Dumbbell Basin where I'd seen lots of frogs during a backpack trip in the early 1990s but by the time we surveyed that site there wasn't a frog to be found. These observations nagged at me but still lacked any broader context. In contrast, my recent analyses of survey data from more than 2000 lakes had clearly shown the negative effect of fish on frogs, and early results from two fish removal experiments conducted by me and by Vance Vredenburg showed dramatic increases in the frog populations at these sites just a few years after fish removal. Restoration of frog populations wasn't going to be easy because fish were so ubiquitous but at least we had the tools to reverse the decline of the mountain yellow-legged frog. To my eyes, the future looked bright.

The first lake I surveyed on that Monarch Divide trip was at the head of the Gorge of Despair. Looking down on the lake from above I could only smile. There should be gobs of tadpoles in that warm cove on the north side of the lake, I thought, and adult frogs will be sunning by the hundreds on those granite slabs near the outlet. An hour later I had finished the survey and could only shake my head. I'd found only four mountain yellow-legged frog tadpoles and had not seen a single adult. Even more alarming was that the tadpoles were clearly sick. We didn't have an accurate method of detecting Bd in those days but my notes on the datasheet that I filled out that day had an ominous tone: "All four tadpoles were large (~3 years old). The one individual I was able to catch had only a partial beak and no toothrows. Skin had a mottled appearance. Chytrid fungus?". Every subsequent day produced similar observations. In lake after lake where frogs had been abundant just a few years earlier we found either no mountain yellow-legged frogs or only a few tadpoles, all with mouthpart deformities suggestive of Bd infection.

Twenty days later, surveys completed and out of food, we hiked down the Copper Creek trail to Cedar Grove. On that long hot descent I struggled to put all of the pieces together. Frog die-offs in western Sequoia National Park in the 1970s and 1980s, healthy frog populations throughout the eastern portions of Sequoia and Kings Canyon National Parks, and now evidence of recent and ongoing die-offs along the Monarch Divide and Cirque Crest.... Could it be that Bd had been spreading from west to east across this part of the Sierra Nevada since the 1970s and that even those huge frog populations in places like Barrett Lakes Basin and Sixty Lake Basin might someday also succumb to this plague? The thought sent shivers down my spine and haunted me for years.

I called Dave Bradford the next day and before I could describe to him what we'd seen on our trip I somewhat immodestly blurted out, "I know what wiped out your frogs on the Tablelands - the chytrid fungus!". I don't know what he thought of my remark or the subsequent description of lake after lake with hardly a frog to be found, but I had seen the future of the mountain yellow-legged frog and it filled me with a profound sense of dread. All that I knew was about to change and the frogs that to me had become as much a part of the Sierra Nevada as the towering granite peaks were soon to be pushed aside by an unseen and unstoppable force.

And so it has come to be. Many of the lake basins where I counted thousands of frogs in the late 1990s are now frogless.
When I walk along a lake shoreline no frogs jump into the water from their grassy hiding places. The shallows where tadpoles used to congregate by the thousands on warm afternoons, thrashing frantically in their retreat to deeper water when I approached, are calm and placid now. The mayflies and beetles are still in abundance in the nearshore waters and on the surface the lakes are as beautiful as ever, but these lakes are profoundly changed, perhaps forever. The same could be said of that idealistic young biologist....

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February 23, 2009

Save the Frogs Day - April 28 2009

April 28, 2009 is the first annual Save the Frogs Day. Check out for more information.

The San Francisco Chronicle had a story on efforts to combat the amphibian chytrid fungus in their 2/19/2009 edition. The battle continues....

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February 17, 2009

Salamanders Declining in Latin America

My research on amphibian declines focuses almost exclusively on mountain yellow-legged frogs. As such, it is easy to forget the fact that the amphibian decline phenomenon has a global reach and that these declines affect a huge diversity of amphibian species. Compared to the large body of evidence showing declines in frogs and toads, evidence for salamander declines has been sparse but a new paper in the Proceedings of the National Academy of Sciences (available here) brings these declines into startling focus. Rovito et al. describe the disappearance of multiple salamander species from montane sites in Mexico and Guatemala (figure from paper showing these declines is shown to left). Surveys conducted at the study sites in the 1970s turned up more than 70 salamanders per visit but surveys in 2005-2007 at the same sites turned up fewer than five salamanders per visit. Several of the most common species during the 1970s were not found during any of the recent surveys and may be extinct.

Given the very high diversity of salamanders in the Neotropics these declines suggest that many salamander species may be at much higher risk of extinction than has been appreciated. Unfortunately the cause of the declines described by Rovito et al. remains obscure. The amphibian chytrid fungus was detected on some salamanders at the study sites and could be a contributing factor as could climate change.

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February 9, 2009

Captive Breeding Inches Closer to Reality

A couple of weeks ago, I attended the annual meeting of the Amphibian Populations Task Force in Bodega Bay. The dozens of talks over two days provided an abundance of new data from a wide array of amphibians in California and Nevada. Perhaps the most relevant information for conservation of the mountain yellow-legged frog was the announcement that the captive population of southern mountain yellow-legged frogs (Rana muscosa) being maintained at the San Diego Zoo (see my previous post for details) had produced a clutch of eggs. To my knowledge this is the first time mountain yellow-legged frogs have bred successfully in captivity. The ongoing reproductive activity of animals in the captive population has raised hopes that numerous additional egg masses might yet be laid this year. If such success continues this captive colony might play an important role in the recovery of these highly endangered frog populations in southern California's Transverse Ranges. (The above photo shows an R. muscosa egg mass from the Sierra Nevada.)

Although I have strong reservations about using captive breeding as a primary strategy to conserve mountain yellow-legged frogs, the southern California populations are in such bad shape that captive breeding may be one of the best options left. Populations in some parts of the Sierra Nevada remain robust enough that captive breeding is not yet needed. I hope we never get to the point where captive breeding of these Sierran populations becomes necessary. But if we do need to go this route in the future, it is somewhat reassuring to know that the techniques to house and breed these frogs in captivity are already being developed.

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February 2, 2009

Effects of Frog Declines on Bears in the Sierra Nevada

A few years ago, Dave Graber (Chief Scientist, Pacific Southwest Region of the National Park Service) asked me a question that I've never been able to get out of my head. Dave, who studied black bears in the Sierra Nevada for many years, asked me if there was a connection between the dramatic decline of mountain yellow-legged frogs in the 1970s and the coincident increase in the number of bears frequenting campgrounds and mountain towns. As an example, he mentioned that black bears were essentially absent from the eastern Sierra until the 1970s, and today the town of Mammoth Lakes alone is home to dozens of dumpster-diving ursines. I'm afraid my answer was little more than "we know that bears feed on frogs so the potential exists for frog declines to affect bears". Unfortunately we'll never know the answer to Dave's question because mountain yellow-legged frogs no longer play the important ecological role they once did as the most abundant vertebrate in the Sierra Nevada.

But what do we know about this frog-bear interaction? Over the years we've made numerous observations of bears feeding on frogs. Those I made in a fishless basin in Kings Canyon National Park in 1997 still haunt me today. This unnamed basin has never been stocked with fish and in 1997 virtually every lake was full of mountain yellow-legged frogs and tadpoles. Frog counts from that 1997 visit were 11,330 frogs and 107,750 tadpoles. During that time it was rare to walk around a lake without stumbling across numerous bear shits. In a shallow cove of one lake, tadpoles aggregated by the thousands to take advantage of the warm water found there every afternoon. Bear tracks ringed the cove shoreline and frequently veered into the lake where tadpoles were particularly dense. The only way to make sense of these observations was if bears were feeding on the abundant tadpoles. The frog population
in this basin crashed about seven years ago due to chytridiomycosis, and during recent visits bear sign seems much scarcer than it was 12 years ago.

I've witnessed something similar in Humphreys Basin following fish removal and subsequent frog recovery. In 1997, Marmot Lake contained lots of small trout and a few mountain yellow-legged frogs. Following fish removal, the frog population exploded and more than 3,000 frogs exist at the lake today. As the numbers of frogs increased so did my observations of bear sign which had been nonexistent during all of my previous years spent at this lake. Marmot Lake doesn't seem like typical bear habitat given its very high elevation but it is now not uncommon to see bear tracks all around the lake shoreline. I'm guessing that the motivation for such shoreline ambulations are the little frog snacks found there.

Given the historic abundance of mountain yellow-legged frogs in the Sierra Nevada I suspect that frogs were often included in bear diets. And maybe, just maybe, the decline of frogs has driven bears into campgrounds and towns in search of alternate food sources. Maybe someday those backcountry lakes will once again contain an abundance of frogs sufficient to interest a hungry bear.

So, as I've said many times before, although the frog restoration issue is often couched simplistically as "fish versus frogs", the issue is in fact much broader.

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January 26, 2009

The Politics of Trout Removal - A Global Phenomenon

I've written a fair bit lately about controversies surrounding trout stocking and trout removal. A theme running through many of these posts is that the politics of trout management strike an emotional chord with many members of the angling community, and sometimes those emotional responses get in the way of science-based management decisions. Although I've focused my posts on this topic specifically on the Sierra Nevada, an email I received recently made it clear that the situation we face in the Sierra Nevada is not unique. Geoff Heard is a PhD student in the Department of Zoology at La Trobe University in Victoria, Australia and had this to say:
Dear Roland:

I have just been reading your Frog Blogs, and felt I must drop you a line. I have been aware of your work with Rana muscosa for sometime - I'm undertaking a PhD on the metapopulation dynamics of the endangered growling grass frog in Melbourne, Australia, and specifically, the impacts of urbanization on those dynamics.

Growling grass frogs like it warm, so they generally don't mix with trout, and thankfully that means I don't butt heads with the trout lobby. However, your situation with Rana is remarkably similar to one here in Victoria. Our case involves the spotted tree frog (Litoria spenceri), an endangered species that lives in mountain streams and has been shown to be very sensitive to trout predation (and suffering from the additive effect of chytridiomycosis). We had a concerted push a few years back to eradicate trout at two remnant L. spenceri sites, but the proposal was terminated by the trout lobby. Just as you describe, a few particularly vocal folk created an uprising by the fishing community, despite the fact that the proposal involved only small sections of two of the state's hundreds of trout streams, and that these sections are basically unfishable (narrow streams, densely vegetated, and containing only small fish). It created so much heat that the relevant official shelved the proposal and gagged the relevant scientists. And the spotted tree frog? Its decline continues to be monitored, but the most easily implemented and arguably most effective recovery action we know of remains off-limits.

So I wanted to congratulate on your great work, and encourage you to push on. Your work will not only benefit Rana, but also adds valuable weight to calls here in Oz for the case of the spotted tree frog versus trout to receive another (hopefully fairer) hearing.


Ah, the politics of trout removal.... It is good to know that we are not alone here in California in our interest in maintaining populations of nonnative trout in virtually every habitat where they could possibly survive regardless of the consequences to all of those useless native species. Sigh.

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January 5, 2009

Involving the Public in Lake Restoration Programs

Sequoia-Kings Canyon and Yosemite National Parks are both preparing draft aquatic management plans that will describe several potential scenarios designed to restore native aquatic fauna while continuing to provide abundant opportunities for recreational fishing. Both plans will likely be released to the public in the next 6-12 months. These draft plans will provide an unprecedented opportunity for interested members of the public to have input into the Park-wide management of lakes and streams in these areas. Details on the Sequoia-Kings Canyon planning process are available here and those on the Yosemite plan are available here. Send a note to each Park (contact info in the above links) to be added to mailing lists for these planning processes. If you provided comments during the scoping period related to these plans you are already on their mailing lists.

On federal lands outside these national parks, the California Department of Fish and Game (CDFG) is currently developing watershed-based plans that describe the future management of fish (including fish stocking) and amphibians. These planning efforts have so far not been open to the public and completed plans are not publicly available. An example plan (for the Big Pine Creek watershed - near Bishop, California) is available here. This effort is being coordinated by CDFG senior biologists in Regions 2, 4, and 6 and overseen by Curtis Milliron. CDFG staff in Region 1
(includes Trinity Alps, Marble Mountains, Caribou Wilderness) and Region 4 (includes the western portion of the John Muir Wilderness and wilderness areas west of Kings Canyon National Park) have so far opted not to prepare management plans but I suspect that this will change in the near future. If you are interested in planning efforts in a particular area, I'd suggest calling the senior biologist responsible for that particular region. A map of the seven CDFG regions and associated contact information is available here.

On an unrelated note, since the new year I've strayed from my usual weekly posts due to obligations that have kept me away from my desk more often than not. I'll do my best to make future posts on Monday of each week.

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