Table 1.

Finch species sampled in this study, including information about general diet category, sampling island, and number of specimens collected during each of the dry and wet season

Species	Common name	Diet category	Island	No. samples (season)
				Dry	Wet
G. septentrionalis	Vampire finch	Carnivorous2, inc. blood	Wolf	16	0
			Darwin	15	0
G. acutirostris	Sharp-beaked ground finch	Insectivorous3	Genovesa	6	0
G. difficilis	Sharp-beaked ground finch	Insectivorous3	Pinta	3	0
G. fortis	Medium ground finch	Herbivorous (seeds)4	San Cristóbal	1	5
			Santa Cruz	3	1
			Santa Fé	0	1
G. fuliginosa	Small ground finch	Herbivorous (seeds)4	Española	0	5
			North Seymour	0	1
			San Cristóbal	7	8
			Santa Cruz	4	1
			Santa Fé	0	1
G. magnirostris	Large ground finch	Herbivorous (seeds)4	Genovesa	2	0
			Pinta	3	0
G. conirostris	Large cactus finch	Herbivorous (Opuntia cactus)	Española	0	2
			Genovesa	2	0
G. scandens	Cactus finch	Herbivorous (Opuntia cactus)	Santa Cruz	3	1
			Santa Fé	0	2
Ce. olivacea	Green warbler finch	Insectivorous	Española	0	4
			Pinta	3	0
C. parvulus	Small tree finch	Insectivorous	San Cristóbal	4	2
			Santa Cruz	0	4
C. pallida1	Woodpecker Finch	Insectivorous	Santa Cruz	0	1
P. crassirostris	Vegetarian finch	Herbivorous (leaves)	Santa Cruz	0	3
Total	12 Species	–	9 Islands	72	42

Genus abbreviations: C = Camarhynchus, Ce = Certhidia, G = Geospiza, P = Platyspiza

¹The solitary C. pallida sample was excluded from statistical analyses

²During the dry season, G. septentrionalis eats blood, eggs, scat of the Nazca boobies

³Although these finch species are classically identified as seed-eaters, behavioral observations at the time of collection indicated that G. difficilis on Pinta was foraging on 100% insects in both wet and dry seasons, and G. acutirostris on Genovesa fed 98% on insects in the wet season, and 80% on insects in the dry season

⁴While these finches predominantly eat seeds, they consume insects on occasion