(199) as at Kaibab (65) for sites with similar foliage 

 volume and snag density. There were more than six 

 times the number of white-breasted nuthatches at 

 Trumbull than at Kaibab. This supports one obser- 

 vation made by Cunningham and others (1980) of a 

 positive correlation between white-breasted nut- 

 hatches and Gambel oak. No brown creepers were 

 observed on any of the locations. 



Table 1 presents a summary of bird numbers and 

 canopy-related habitat variables. Trumbull plots 

 had slightly higher mean canopy cover and food 

 availability, similar mean height and foliage vol- 

 ume, and fewer snags than Kaibab plots. 



Spearman correlation coefficients (r) were com- 

 puted between bird numbers and all habitat vari- 

 ables for the two study areas separately and com- 

 bined and are presented in table 2. Correlation 

 coefficients between bird numbers and habitat 



Table 1 — Summary of average number of birds and habitat variables per plot 

















Average 



Ponderosa 



Other 





Number 







wniie 



Mountain 





Pygmy 





Crown 



height 



pine 



tree 



Woody 



snags 



rOOu 



Location 



breasted 



chicka- 



House 



nut- 



Total 



canopy 



tallest 



foliage 



foliage understory 



>1 u.^ 



availability 



number 



nuthatch 



dee 



wren 



hatch 



guild 



cover 



trees 



volume 



volume 



cover 



cm/ha 



index 









Number - 







Percent 





m^/ha 



Percent 





















m 





















Study area 1 (Kaibab) 













01 



1.0 



0.5 



0.5 







2.0 



51 



28 



60,864 







9 



1.3 



1.00 



02 



1.0 



.5 











1.5 



57 



26 



16,661 



4,318 



12 



1.3 



1.00 



03 















3.5 



3.5 



37 



27 



59,519 











.3 



.84 



04 



.5 



2.5 











3.0 



21 



29 



36,641 











.7 



.63 



05 



.5 



2.0 











2.5 



46 



10 



25,964 







1 



.3 



.79 



06 



.5 



6.0 











6.5 



42 



16 



15,055 



4,586 



29 



.2 



.89 



07 























35 



22 



35,289 



1,229 



24 



.5 



.84 



08 



1.5 



5.5 











7.0 



16 



13 



11,495 



5,796 



29 



.3 



.52 



09 



.5 



2.0 



2.0 



6.5 



11.0 



49 



28 



35,226 







9 



2.3 



1.00 



10 



1.5 



3.0 



15 



8.0 



14.0 



81 



30 



89,253 







6 



3.2 



.95 



11 























65 



16 



59,004 











.8 



1.00 



12 



1.0 



13.0 











14.0 



20 



15 



8,582 



6,578 



50 



.3 



.63 



Mean 



.7 



2.9 



.3 



1.5 



5.4 



43 



22 



37,796 



1,876 



14 



1.0 



.84 













Study area 2 (Trumbull) 













13 







6.5 







6.5 



13.0 



23 



21 



34,425 







11 







.71 



14 



6.5 



10.0 







3.5 



20.0 



54 



21 



34,650 



7,272 



35 



.3 



1.00 



15 



4.5 



10.5 







9.5 



24.5 



54 



21 



63,079 



1,445 



1 



.2 



1.00 



16 



.5 



3.0 







1.0 



4.5 



75 



18 



1 5,998 



9,689 







2 



1.00 



17 



4.0 



7.0 







7.5 



18.5 



58 



14 



60,232 



4,529 



6 







.95 



18 



5.0 



4.5 



1.0 



5.5 



16.0 



80 



27 



53,987 



1,222 







.3 



.95 



19 



7.0 



6.5 







14.5 



28.0 



48 



26 



64,622 



9,137 



11 



1.5 



1.00 



20 



4.5 



7,5 







10.5 



22.5 



50 



23 



37,752 



4,358 



17 



1.2 



1.00 



21 























5 



13 



8,408 







14 



.3 



.30 



22 



.5 



2.0 







3.0 



5.5 



38 



23 



12,894 







16 



.2 



.89 



23 



8.0 



3.5 







9.0 



20.5 



59 



27 



63,423 



1,697 



2 



.5 



1.00 



24 



6.0 



12.5 







7.5 



26.0 



58 



16 



20,308 



382 



4 







1.00 



Mean 



3.9 



6.1 



.1 



6.5 



16.6 



50 



21 



39,148 



3,311 



10 



.4 



.90 



Simple correlation and simple and multiple re- 

 gression were used to analyze the relationships be- 

 tween bird species numbers and the independent 

 habitat variables: average height of tallest trees, 

 crown canopy cover, snag density, foliage volume 

 (ponderosa pine and other), the index of food availa- 

 bility, woody understory vegetation cover, and time 

 since logging. The Spearman test for correlation 

 (SAS 1982) was used because it was assumed that 

 the precision of bird counts was low and because the 

 relationship between variables might not be linear. 



RESULTS 



The relationship between bird numbers and habi- 

 tat variables varied depending on study area. Total 

 numbers of the five species of cavity-nesting glean- 

 ers were three times more abundant at Trumbull 



4 



