Patricia B. Jones

Distribution and Relative Abundance of Forest Birds in Relation to Burn Severity in Southeastern Arizona

Abstract The frequency of wild and prescribed fires in montane forests of the southwestern United States has increased after a century of fire suppression and subsequent fuels accumulation. To assess the effects of recent fires (median time since fire = 6 yr) on the montane forest bird community, we surveyed birds in 8 Sky Island mountain ranges in southeastern Arizona, USA, and examined how the distribution (i.e., presence–absence) of 65 species and relative abundance of 16 species correlated with evidence of severe and less severe fire at >1,500 survey points. We detected associations between fire and bird presence–absence for 17% of the 65 species analyzed and between fire and bird relative abundance for 25% of the 16 species analyzed. Most species (73%) were positively associated with burned areas and displayed stronger associations (i.e., more extreme odds ratios) with survey points that had evidence of severe as opposed to less severe fire. Positive associations with severe fire were strong (>3 to 1 odds) for western wood-pewee (Contopus sordidulus) and house wren (Troglodytes aedon), and negative associations with severe fire were strong for warbling vireo (Vireo gilvus) and red-breasted nuthatch (Sitta canadensis). Although recent fires appear to have had a positive effect on the distribution and relative abundance of several montane forest bird species in the region, these species are not the open-woodland birds that we would have expected to have benefited from fire based on previous research. Nevertheless, our results confirm associations between fire and bird presence–absence and relative abundance reported previously for 7 species of birds. Our results also provide new information for Graces warbler (Dendroica graciae) and greater pewee (C. pertinax), 2 species for which fire data were formerly lacking. Managers can use these data to make and test predictions about the effects of future fires, both severe and less severe, on montane forest birds in the southwestern United States.

Comparison of Total Solar Irradiance with NASA/National Solar Observatory Spectromagnetograph Data in Solar Cycles 22 and 23

NASA/National Solar Observatory Spectromagnetograph (SPM) data are compared with spacecraft measurements of total solar irradiance (TSI) variations for 8 yr beginning with the declining phase of solar cycle 22 and extending into the maximum of cycle 23. Previously reported conclusions based on a similar comparison for a shorter time period appear to be robust: three factors (sunspots, strong unipolar regions, and strong mixed-polarity regions) describe most of the variation in the SPM record, but only the first two are associated with TSI. Additionally, the residuals of a linear multiple regression of TSI against SPM observations over the entire 8 yr period show an unexplained, increasing, linear time variation with a rate of about 0.05 W m-2 yr-1. Separate regressions for the periods before and after 1996 January 1 show no unexplained trends but differ substantially in regression parameters. This behavior may reflect a solar source of TSI variations beyond sunspots or uncompensated nonsolar effects in one or both of the TSI and SPM data sets.

Factorial Invariance of the California Achievement Tests Across Race and Sex

The six subtests of the California Achievement Tests were factor analyzed separately for black males, black females, Hispanic males, Hispanic females, white males, and white females in the fifth- and seventh-grades. One factor best described the factor structure of the test of each group. The structures of each group were compared by using coefficients of congruence. The California Achievement Test was found to be essentially invariant with regard to race and sex.

Validity of the Standard Progressive Matrices as a Predictor of Achievement of Sixth and Seventh Grade Students.

The predictive validity of the Standard Progressive Matrices(SPM) was examined with a sample of 212 sixth grade students and 214 seventh grade students. Correlation coefficients between the SPM and the California Achievement Tests of Reading, Language, and Mathematics ranged from .34 to .60. Those coefficients were similar in range and magnitude to those coefficients reported by the SPM Manual.

COMPARISON OF ITEM RESPONSES OF ENGLISH- AND SPANISH-SPEAKING CHILDREN USING MINIMUM LOGIT CHI-SQUARED REGRESSION

A total of 102 Spanish-speaking preschool pupils and 104 English-speaking pupils were individually administered the Spanish and English versions of the Cooperative Preschool Inventory. Minimum logit chi-squared regression was applied to each of the 33 items of the verbal scale of the inventory. Several differences in the response patterns of the two groups were noted, although the number of potentially biased items was small (12%).

Two Basic Programs to Compute Hotelling's T2 Statistic

This paper describes two BASIC computer programs that calculate Hotellings T2 statistic either for one sample or for two samples. Output of the program includes the Mahalanobis distance D2 , the F ratio associated with T2 , and its probability level.

A Basic Computer Program for Calculating Simultaneous Pairwise Comparisons in Analysis of Covariance

This paper describes a BASIC microcomputer program that computes all pairwise comparisons of means after analysis of covariance using the Tukey-Kramer test. Input to the program consist of the means of the covariate, the adjusted criterion means, the sample size, mean square error from a one-way analysis of covariance, and the 95th percentile point on the Studentized range distribution.

Reliability and Validity of the Language Proficiency Measure

A total of 101 English-speaking Hispanic and 97 Spanish-speaking Hispanic pupils in Grade K-3 were administered the Language Proficiency Measure (LPM). Results indicated that the interrater reliability was adequate, internal-consistency reliability estimates were high, concurrent validity coefficients were adequate, and the classification validity was acceptable. These findings provided substantial evidence supporting the reliability and validity of the LPM.