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Collectively, these papers indicate that the effects of widespread trout introductions into wilderness landscapes are not limited simply to direct effects on prey taxa, but instead can be transmitted throughout lake food webs and even beyond the shorelines of fish-containing lakes to fishless lakes. In addition, following fish removal, full recovery of ecosystem structure and function may not occur. These results pose a difficult challenge for fisheries and wilderness managers interested in better balancing the conflicting goals of maintaining nonnative fisheries in wilderness areas while also minimizing the effects of these fisheries on natural processes. If managers are to truly balance these often opposing goals, it is imperative that current fisheries management practices be evaluated in the context of their effects on ecosystem and landscape processes. It is our hope that this special feature will provide the impetus for such an evaluation and for the adoption of new management strategies to reduce the ecological impacts of nonnative fisheries in protected areas.

The fungal pathogen Batrachochytrium dendrobatidis (Bd) causes chytridiomycosis, a disease implicated in amphibian declines on 5 continents. We developed filtering and PCR based quantiative methods to detect Bd in water and sediments. Our methods provide a new tool to investigate critical aspects of Bd in the environment.

Tailed frogs (Ascaphus spp.) oviposit in cryptic locations in streams of the Pacific Northwest and Rocky Mountains. This aspect of their life history has restricted our understanding of their reproductive ecology. The recent split of A. montanus in the Rocky Mountains from A. truei was based on molecular differentiation, and comparisons of their ecology are limited. Our objectives were to provide a range-wide summary of information on Ascaphus oviposition,compare some aspects of the reproductive ecology of the 2 species, and examine geographic variation in their reproductive traits. Reproductive ecology of the 2 species differed. Ascaphus truei had smaller clutches, oviposited later in the summer, and had a longer duration of oviposition than A. montanus. A greater number of communal oviposition sites were attributed to A. montanus. These ecological differences support the recent taxonomic revision of Ascaphus and suggest that different management strategies may be necessary for each species where conservation is a priority.

Natural history note

Note

We describe a commercially-available funnel trap for sampling aquatic vertebrates. The traps can be used in heavily vegetated wetlands and can be set in water up to 60 cm deep without concern for drowning the animals. They were especially useful for capturing the aquatic salamanders Siren lacertina and Amphiuma means, which have been difficult to capture with traditional sampling methods. They were also effective for sampling small fishes, particularly centrachids, and larval anurans. In total, 14 species of amphibians, nine species of aquatic reptiles, and at least 32 fish species were captured. The trap we describe differs significantly from funnel traps (e.g., minnow traps) and holds great promise for studies of small, aquatic vertebrates, in particular Siren and Amphiuma species.