Migration timing and tributary use of spawning flannelmouth sucker (Catostomus latipinnis).

Spawning phenology and associated migrations of fishes are often regulated by factors such as temperature and stream discharge, but flow regulation of mainstem rivers coupled with climate change might disrupt these cues and affect fitness. Flannelmouth sucker (Catostomus latipinnis) persisting in heavily modified river networks are known to spawn in tributaries that might provide better spawning habitat than neighboring mainstem rivers subject to habitat degradation (e.g.

Parasites and salinity: costly tradeoffs in a threatened species.

Parasites and environmental conditions can have direct and indirect effects on individuals. We explore the relationship between salinity and parasites in an endemic New Mexico State threatened fish, the White Sands pupfish (Cyprinodon tularosa). Spatial variation in salinity limits the distribution of the endemic springsnail (Juturnia tularosae) within Salt Creek, a small desert stream.

Typical dioxin concentrations in agriculture soils of Washington state and potential sources.

Background or typical levels of polychlorinated dibenzo-p-dioxins and of polychlorinated dibenzo-p-furans in soils have become increasingly important in the regulatory community, as dioxins have come under increased scrutiny due to their toxicity and persistence. Knowing the typical levels of dioxin in soils is important to set regulatory levels, to prevent further contamination, and for setting cleanup levels. A random sample (n=54) of agricultural lands within Washington state revealed a typical concentration of "dioxin" of 0.