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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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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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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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 (www.amphibiaweb.org). 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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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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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: http://www.wildlifeextra.com/go/news/mountain-chickens472.html#cr

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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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 [link].

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