Table 2.

Estimated annual consumption of arthropod prey (fresh weight) of the global population of insectivorous birds. Values for temperate biomes refer to residents and breeding migrants combined; values for tropical biomes refer to residents and non-breeding migrants combined. Not included in these calculations are the amounts of arthropod prey consumed at migration stopover sites

Biome class	Number of assessments	Prey consumption (kg ha−1 year−1)*	Area (ha)	Prey consumption of entire area (kg year−1)
		(X)	(Y)	(X) × (Y)
Tropical forestsa	7	112.5 ± 9.2	1750 × 106	196,875 × 106
Temperate and boreal forestsb	44	44.1 ± 6.2	2410 × 106	106,281 × 106
Tropical grasslands and savannas/Mediterranean shrublandc	7	15.8 ± 2.8	3040 × 106	48,032 × 106
Temperate grasslands (incl. meadows, pastures, old fields)d	11	7.5 ± 0.9	1500 × 106	11,250 × 106
Croplande	8	20.9 ± 9.0	1350 × 106	28,215 × 106
Desertsf	18	4.1 ± 0.8	2770 × 106	11,357 × 106
Arctic tundrag	8	4.6 ± 1.3	560 × 106	2576 × 106
Global total (without ice-covered area)	103	–	13,380 × 106	404,586 × 106

^aKarr (1975); Leigh and Smythe (1978); Reagan and Waide (1996); Robinson et al. (2000); Sakai (2002)

^bTima (1957); Uramoto (1961); West and DeWolfe (1974); Holmes and Sturges (1975); Karr (1975); Alatalo (1978); Szaro and Balda (1979); Smith and MacMahon (1981); Wiens (1989) (modified data from Wiens and Nussbaum 1975); Wiens (1989) (modified data from Weiner and Głowaciński 1975; Głowaciński and Weiner 1980, 1983); Weathers (1983); Keast et al. (1985); Solonen (1986); Kartanas (1989); Harris (1991)

^cKarr (1971); UNESCO (1979); Gillon et al. (1983)

^dDiehl (1971); Wiens (1977); Rotenberry (1980b); Smith and MacMahon (1981); Głowaciński et al. (1984); combined data Faanes (1982)/Kirk et al. (1996)

^eWiens and Dyer (1975); Woronecki and Dolbeer (1980); Kartanas (1989); Ferger et al. (2013)

^fCombined data Lasiewski and Dawson (1967)/Austin (1970)

^gWielgolaski (1975); combined data Lasiewski and Dawson (1967)/Watson (1963); James and Rathbun (1981); Montgomerie et al. (1983); Sokolov et al. (2012)

^*Values of prey kill (kg ha⁻¹ year⁻¹) presented as x̅ ± SE