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Many techniques for assessing lipid reserves have been used, but techniques are seldom evaluated. We evaluated five common methods (fat scoring, regression residuals of body mass vs. morphological measurements, quotients of body mass divided by morphological measurements, total body electrical conductivity, and water content) for assessing lipid reserves in the Wood Thrush (Hylocichla mustelina) in Rhode Island. Lipid content ranged from 3 to 1 l%, water content ranged from 64 to 72%, and fat score ranged from 0 to 4. Mean total body electrical conductivity (TOBEC) was moderately correlated with lean body mass. Percentage water and fat score were highly correlated with extracted lipid mass and percentage lipid content. Body mass, tail x mass regression residuals, and quotient of body mass/tail length were highly correlated with lean body mass. Morphological measurements were correlated with lean mass only when in association with body mass, but not considered alone. Combining TOBEC readings with body mass and morphological measurements produced regression models with similar predictive abilities as previous studies using TOBEC, but TOBEC provided little or no additional predictive ability. TOBEC did not significantly improve body fat predictive models and does not appear accurate in predicting lipid mass of individual small birds. Fat score and percentage water are useful indices of body fat in Wood Thrush.

Measuring only about the size of a sparrow, the diminutive black rail is the smallest North American rail. Adult black rails are dark gray or nearly black overall with a variable amount of scattered white spotting on the back that may also extend onto the wing coverts and secondaries. The nape and upper back are deep chestnut colored. The dark gray undertail coverts and flanks are streaked with white or light gray. The tail is short and grayish-brown. The bill is short and black and the legs and feet are grayish-brown. Although the sexes are similar in size, they differ slightly in plumage. The throat of the female may be pale gray or white, while that of the male may be pale to medium gray. Juvenile black rails resemble adults but are duller gray overall with less spotting above and thinner streaking on the flanks. Eye color, which changes with age, is red in adults and may range from brown to orange in juveniles. The black rail is an elusive species that typically walks or runs rather than flies. Due to its secretive nature and nocturnal habits, this rail is more often heard than seen. The black rail's call, a repeated kic-kee-doo or kic-kic-kerr, may be given throughout the night but is most frequently voiced during the first few hours after sunset or before sunrise. Rarely, black rails may vocalize during the day. Vocal activity is greatest during the early breeding season, from late April to mid-May. Adults and young may communicate using kik or yip calls.