Fungicide use on row crops is increasing dramatically due to promotion of these products for general plant health and increased yield even during low disease pressure. These fungicides are applied aerially, which may lead to amphibian exposure within fields or in nearby habitat. Exposure to three of these fungicides at environmentally relevant conditions resulted in mortality for Bufo tadpoles and juveniles for two of the fungicides. Headline®, the most commonly used on row crops, resulted in >50% mortality for juveniles at corn label application rates and 100% mortality for tadpoles at one-tenth the label rate for corn. Stratego® killed 40% of exposed tadpoles on average at the corn label rate, but only 7% of the juveniles. Overall, Quilt® appeared less toxic than the other fungicides, resulting in 7 to 10% mortality of tadpoles and 4 to 22% mortality of juveniles at all concentrations (from 0.1× to 10× label rate). These fungicides, especially Headline, may pose a major hazard for amphibians exposed as tadpoles and/or juveniles at environmentally relevant concentrations.

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Playas are shallow depressional wetlands and the dominant wetland type in the non‐glaciated High Plains of the United States. This region is one of the most intensively cultivated regions in the Western Hemisphere, and playas are profoundly impacted by a variety of agricultural activities. Conservation practices promoted through Farm Bills by the U.S. Department of Agriculture (USDA) that influence playas and surrounding catchments impact ecosystem functions and related services provided by wetlands in this region. As part of a national assessment, we review effects of agricultural cultivation and effectiveness of USDA conservation programs and practices on ecosystem functions and associated services of playas. Services provided by playas are influenced by hydrological function, and unlike other wetland types in the United States, hydrological function of playas is impacted more by accumulated sediments than drainage. Most playas with cultivated catchments have lost greater than 100% of their volume from sedimentation causing reduced hydroperiods. The Conservation Reserve Program (CRP) has the largest influence on playa catchments (the High Plains has >2.8 million ha), and associated sedimentation, of any USDA program. Unfortunately, most practices applied under CRP did not consider restoration of playa ecosystem function as a primary benefit, but rather established dense exotic grass in the watersheds to reduce soil erosion. Although this has reduced soil erosion, few studies have investigated its effects on playa hydrological function and services. Our review demonstrates that the Wetlands Reserve Program (WRP) has seldom been applied in the High Plains outside of south‐central Nebraska. However, this is the primary program that exists within the USDA allowing conservation practices that restore wetland hydrology such as sediment removal. In addition to sediment removal, this practice has the greatest potential effect on improving hydrologic function by reducing sedimentation in vegetative buffer strips. We estimate that a 50‐m native‐grass buffer strip could improve individual playa hydroperiods by up to 90 days annually, enhancing delivery of most natural playa services. The potential for restoration of playa services using USDA programs is extensive, but only if WRP and associated practices are promoted and playas are considered an integral part of CRP contracts.

Morelet's crocodile Crocodylus moreletii has not been well-studied and many aspects of its life history are unknown. In particular there is a notable paucity of information on nesting and reproductive ecology. We studied the nesting ecology of Morelet's crocodile in northern Belize from 1992 through 1995. Nesting occurs at the onset of the wet season in mid-June and continues through mid-July (mean oviposition date = 1 July AE 10 days). Eggs hatch from mid-August through midto late September. Nesting effort at our primary study site remained relatively constant during 1992, 1993 and 1995, but nearly doubled in 1994; this appeared to reflect a regional trend. Natural and man-made islands are heavily used as nesting sites. Nesting success in 1993 and 1994 was consistently higher on natural islands when compared with man-made islands or shoreline sites. Nest losses were primarily due to flooding and raccoon Procyon lotor predation. Losses from predation were greatest in 1994 when unseasonably low water levels facilitated predator access to nests. Females probably reach sexual maturity in 7-8 years after attaining a total length of 150 cm. Mean clutch size (25.0 AE 7.6; range =9-42; n = 73) did not differ among years. Mean clutch size, egg width (EW), egg length, egg mass (EM) and clutch mass were positively correlated with female snout-vent length (SVL). Mean EW was the best predictor of female SVL. A partial correlation analysis of egg and clutch attributes found that independent of female SVL, EM increases with increasing clutch size.