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At the request of the U.S. Fish and Wildlife Service (USFWS) and the Florida Fish and Wildlife Conservation Commission (FWC), we provide an independent assessment of the reliability of the scientific literature used to support conservation of Florida panthers (Puma concolor coryi). We independently reached similar conclusions about unreliable scientific inferences before discussing the issues with each other or with others. Although a quarter-century of research supports many published conclusions, 2 sets of unreliable inferences may compromise efforts to conserve the species The first is a set of 4 unreliable inferences that underlie the Panther Habitat Evaluation Model (PHEM), used by agencies to evaluate projects that may affect panther habitat. Specifically, the following assertions are unreliable: 1) panthers are forest obligates, 2) panthers require large (>500 ha) forest patches, 3) panthers are reluctant to cross 90-m gaps of nonforest habitat, and 4) the value of potential panther habitat declines linearly with distance to a population core in south Florida, USA. These assertions are unreliable because the analyses excluded (without mention or rationale) almost half the available data, compared used habitats to an inappropriate set of available habitats, made inferences about habitat preference without any data on available habitats, were based only on panther locations during daytime, ignored telemetry error, or suffered from other flaws. The second is a set of 2 unreliable inferences about panther demography prior to the genetic restoration effort initiated in 1995. Inferences that neonate survival was ≥0.84 and that the panther population was demographically vigorous prior to 1995 are flawed because the survival analysis ignored mortality during the first 4 months and because other inferences were based on numbers of births and deaths in samples of convenience rather than appropriate vital rates. These faulty inferences about panther demography brought unwarranted credibility to challenges of the genetic restoration program. Faulty inferences of both sets were repeated in subsequent scientific and popular articles; in several instances, previously published work was miscited. In its current (2002-2005) version, PHEM is unreliable and should not be used in decisions about panther habitat. Biologists should obtain better demographic estimates and fully analyze how the introgression program has affected these rates. [ABSTRACT FROM AUTHOR]

Black bear (Ursus americanus) populations are most often managed based on sex and age composition of hunter-killed bears, but few studies have evaluated the method used to determine age. We assessed the accuracy and consistency of aging black bears in New Mexico using the cementum annuli technique by examining age estimates obtained for research-captured and hunter-killed bears. Age estimates were 80% accurate for 30 teeth obtained from 26 known-age bears. Age estimates were consistent with field estimates of age-class for 76% of 232 teeth obtained from captured bears when actual age was not known. Age estimates were consistent between paired teeth for 74% of 232 pairs taken from hunter-killed bears on the same day but for only 46% of 61 pairs taken from study bears during the same or different years. Errors or inconsistencies in age estimation increased with known or estimated age, certainty codes provided by the laboratory, and tooth breakage, but these 3 factors were correlated. Accuracy and consistency also were lower when teeth were removed during the den season. Evidence did not indicate any difference in accuracy and consistency between sexes. In comparisons of 2 blind samples obtained independently, estimated age composition of the harvest did not differ (P=0.92). Accuracy and consistency of the cementum annuli aging technique were relatively high for bears with known or estimated ages < 5 years old; therefore, the method appeared adequate for assessing age composition of annual hunter harvests in New Mexico. [ABSTRACT FROM AUTHOR]