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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 124. No. 3. September 2012 
(A) 
FIG. I. Resident (A) and migrant (B) birds by habitat preference in live agroforestry system classes in Tabasco. Mexico 
in 2008 and 2009. WB = water bodies; FS = forest specialists; FG = forest generalists; OAS = open area specialists 
AF = agroforest; AA = animal agroforestry; LA = linear agroforestry; SA = sequential agroforestry; CT = crops under 
tree cover. Scale on Y-axis in (B) is adapted. 
agroforestry, and crops tinder tree cover. From 51.7 
to 75.1% of resident birds were forest generalists 
(Fig. 1A) depending on agroforestry class; >93% 
of migrant birds were forest generalists in all 
agroforestry classes (Fig. IB). 
Principal components analysis explained 4S.8% 
ot variation in species composition among agro¬ 
forestry classes on the first three axes. A NOS IM 
with Bray-Curtis' distance measure indicated 
significant differences in community composil 
among agroforestry system classes (R = 0.32 ; 
P = 0.001). Comparisons between pairs of syst 
classes with sequential Bonferroni correc 
^-values indicated significant differences 
agroforests and crops under tree cover with anil 
agroforestry, linear agroforestry, and sequen 
agroforestry (all 1> < 0.005). SIMPER indica 
Great-tailed Crackle. Clay-colored Thrush (Tun 
gray,) and Ob ve-throated Parakeet (A rat in 
nana) contributed most to differences bet we 
agroforests and crops under tree cover with animal 
agroforestry. Great-tailed Grackle and Clay- 
colored Thrush contributed most to the dissimilar¬ 
ity between agroforests and linear agrotoresm 
Clay-colored Thrush and Golden-fronted VorxI- 
pecker contributed most to differences betwee 
crops under tree cover and linear agroton’M 
Melodious Blackbird. Great-tailed Grackle. u* ■ 
Clay-colored Thrush contributed most to ihc di 
ference between communities in agrolore sis- 
sequential agroforestry. Melodious Blacker. 
Clay-colored Thrush, and Golden-fronted WooJ 
pecker contributed most to the difference betwee 
crops under tree cover and sequential agrofonNP 
AN OS IM with abundance data for toracing 
guilds (P-values with sequential Bonferroni sig¬ 
nificance) indicated significant differences 
agroforestry classes (R = 0.19. P - ll(HL 
Linear agroforestry was different from agr c,,lir ' 
esis. sequential agroforestry, and crops under t ^ 
