Food preferences and exploitation are crucial to many aspects of avian ecology and are of increasing importance as we progress in our understanding of community ecology. We studied birds and their feeding specialization in the Central Range of Papua New Guinea, at eight study sites along a complete (200 to 3700 m a.s.l.) rainforest elevational gradient. The relative species richness and abundance increased with increasing elevation for insect and nectar eating birds, and decreased with elevation for fruit feeding birds. Using emetic tartar, we coerced 999 individuals from 99 bird species to regurgitate their stomach contents and studied these food samples. The proportion of arthropods in food samples increased with increasing elevation at the expense of plant material. Body size of arthropods eaten by birds decreased with increasing elevation. This reflected the parallel elevational trend in the body size of arthropods available in the forest understory. Body size of insectivorous birds was significantly positively correlated with the body size of arthropods they ate. Coleoptera were the most exploited arthropods, followed by Araneae, Hymenoptera, and Lepidoptera. Selectivity indexes showed that most of the arthropod taxa were taken opportunistically, reflecting the spatial patterns in arthropod abundances to which the birds were exposed.

Biology Centre CAS Institute of Entomology Branisovska 31 370 05 Ceske Budejovice Czech Republic

The New Guinea Binatang Research Center PO Box 604 Madang Papua New Guinea

University of South Bohemia Faculty of Science Branisovska 1760 370 05 Ceske Budejovice Czech Republic

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Wu Y. et al.. Explaining the species richness of birds along a subtropical elevational gradient in the Hengduan Mountains. Journal of Biogeography 40, 2310–2323 (2013).

Wiens J. A. The ecology of bird communities. Vol. 1 (Cambridge University Press, 1992).

Price T. D. et al.. Niche filling slows the diversification of Himalayan songbirds. Nature 509, 222–225 (2014). PubMed

Pigot A. L., Trisos C. H. & Tobias J. A. In Proc. R. Soc. B. 2015 (The Royal Society) (2013).

Yoshikawa T. & Isagi Y. Dietary breadth of frugivorous birds in relation to their feeding strategies in the lowland forests of central Honshu, Japan. Oikos 121, 1041–1052, doi: 10.1111/j.1600-0706.2011.19888.x (2012). DOI

Remsen J. J. Community organization and ecology of birds of high elevation humid forest of the Bolivian Andes. Ornithological Monographs 36, 733–756 (1985).

Remsen J. J. & Parker T. I. Arboreal dead-leaf-searching birds of the Neotropics. Condor, 36–41 (1984).

Auer S. K. & Martin T. E. Climate change has indirect effects on resource use and overlap among coexisting bird species with negative consequences for their reproductive success. Global Change Biology, n/a-n/a, doi: 10.1111/gcb.12062 (2012). PubMed DOI

Sekercioglu C. H. et al.. Disappearance of insectivorous birds from tropical forest fragments. Proceedings of the National Academy of Sciences of the United States of America 99, 263–267, doi: 10.1073/pnas.012616199 (2002). PubMed DOI PMC

Robinson S. K. & Holmes R. T. Foraging Behavior of Forest Birds: The Relationships Among Search Tactics, Diet, and Habitat Structure. Ecology 63, 1918–1931 (1982).

Terborgh J. Bird species diversity on an Andean elevational gradient. Ecology 58, 1007–1019, doi: 10.2307/1936921 (1977). DOI

Blake, J. G. & Loiselle B. A. Diversity of birds along an elevational gradient in the Cordillera Central, Costa Rica. The Auk 117, 663–686 (2000).

Tvardikova, K. Trophic relationships between insectivorous birds and insect in Papua New Guinea Ph.D. thesis, University of South Bohemia, (2013).

Terborgh J. W. In Proceedings of Interational Ornithological Congress Vol. 17 955–961 (1980).

Rosenberg K. V. & Cooper R. J. Approaches to avian diet analysis. Vol. 13 80–91 (Cooper Ornithological Society, 1990).

Loiselle B. A. & Blake J. G. Diets of understory fruit-eating birds in Costa Rica: seasonality and resource abundance. Studies in avian biology 13 (1990).

Collins B. G., Grey J. & McNee S. Foraging and nectar use in nectarivorous bird communities. Studies in avian biology 13, 110–121 (1990).

Karr J. R. & Brawn J. D. Food resources of understory birds in central Panama: quantification and effects on avian populations. Studies in avian biology 13, 58–64 (1990).

Falcone, J. F. Comparisons of arthropod and avian communities in insecticide-treated and untreated hemlock stands in Great Smoky Mountains National Park, Western Carolina University, (2009).

Janes S. W. Variation in the species composition and mean body size of an avian foliage-gleaning guild along an elevational gradient: correlation with arthropod body size. Oecologia 98, 369–378 (1994). PubMed

Turner A. K. Optimal foraging by the swallow (Hirundo rustica, L): prey size selection. Animal Behaviour 30, 862–872 (1982).

Brose U. et al.. Consumer-Resource Body-Size Relationships in Natural Food Webs. Ecology 87, 2411–2417, doi: 10.2307/20069251 (2006). PubMed DOI

Philpott S. M. et al.. Functional Richness and Ecosystem Services: Bird Predation on Arthropods in Tropical Agroecosystems. Ecological Applications 19, 1858–1867, doi: 10.2307/40346293 (2009). PubMed DOI

Brose U. et al.. Climate change in size-structured ecosystems. Philosophical Transactions of the Royal Society B: Biological Sciences 367, 2903–2912, doi: 10.1098/rstb.2012.0232 (2012). PubMed DOI PMC

Ashmole N. P. Body size, prey size, and ecological segregation in five sympatric tropical terns (Aves: Laridae). Systematic Biology 17, 292–304 (1968).

Cohen J. E., Pimm S. L., Yodzis P. & Saldaña J. Body Sizes of Animal Predators and Animal Prey in Food Webs. Journal of Animal Ecology 62, 67–78, doi: 10.2307/5483 (1993). DOI

Bédard J. Adaptive radiation in Alcinidae. Ibis 111, 189–198, doi: 10.1111/j.1474-919X.1969.tb02526.x (1969). DOI

Hespenheide H. A. Food preference and the extent of overlap in some insectivorous birds, with special reference to the Tyrannidae. Ibis 113, 59–72, doi: 10.1111/j.1474-919X.1971.tb05123.x (1971). DOI

Hespenheide, H. Prey characteristics and predator niche width. Ecology and Evolution of Communities. ML Cody & JM Diamond, eds (1975).

Sam K., Koane B., Jeppy S. & Novotny V. Effect of forest fragmentation on bird species richness in Papua New Guinea. Journal of Field Ornithology 85, 152–167, doi: 10.1111/jofo.12057 (2014). DOI

Schoener T. W. Large-billed insectivorous birds: a precipitous diversity gradient. The Condor 73, 154–161 (1971).

Ganihar S. R. Biomass estimates of terrestrial arthropods based on body length. Journal of Bioscience 22, 219–224 (1997).

Chesson J. The estimation and analysis of preference and its relatioship to foraging models. Ecology 64, 1297–1304 (1983).

Craig J. L., Stewart A. M. & Douglas M. E. The foraging of New Zealand honeyeaters. New Zealand journal of zoology 8, 87–91 (1981).

Olson D. M. The distribution of leaf litter invertebrates along a Neotropical altitudinal gradient. Journal of tropical ecology 10, 129–150 (1994).

Guevara J. & Aviles L. Multiple techniques confirm elevational differences in insect size that may influence spider sociality. Ecology 88, 2015–2023 (2007). PubMed

Larsen T. H., Escobar F. & Armbrecht I. Insects of the Tropical Andes: diversity patterns, processes and global change. Climate Change and Biodiversity in the Tropical Andes. Inter-American Institute of Global Change Research (IAI) and Scientific Committee on Problems of the Environment (SCOPE), São José dos Campos and Paris, 228–244 (2011).

Stork N. E. & Blackburn T. M. Abundance, body size and biomass of arthropods in tropical forest. Oikos. 483–489 (1993).

Janzen D. H. et al.. Changes in the Arthropod Community along an Elevational Transect in the Venezuelan Andes. BIOTROPICA 8, 193–203, doi: 10.2307/2989685 (1976). DOI

Hodkinson I. D. Terrestrial insects along elevation gradients: species and community responses to altitude. Biological Reviews 80, 489–513, doi: 10.1017/s1464793105006767 (2005). PubMed DOI

Powers K. S. & Avilés L. The role of prey size and abundance in the geographical distribution of spider sociality. Journal of Animal Ecology 76, 995–1003, doi: 10.1111/j.1365-2656.2007.01267.x (2007). PubMed DOI

Krebs J. R., Erichsen J. T., Webber M. I. & Charnov E. L. Optimal prey selection in the great tit (Parus major). Animal Behaviour 25, 30–38 (1977).

Price T. Morphology and ecology of breeding warblers along an altitudinal gradient in Kashmir, India. The Journal of Animal Ecology, 643–664 (1991).

Boulter, S., Lambkin, C. L. & Starick, N. T. Assessing the abundance of seven major arthropod groups along an altitudinal gradient and across seasons in subtropical rainforest. (2011).

Poulin B., Lefebvre G. & McNeil R. Diets of Land Birds from Northeastern Venezuela. The Condor 96, 354–367 (1994).

Basset Y. et al.. Arthropod Diversity in a Tropical Forest. Science 338, 1481–1484, doi: 10.1126/science.1226727 (2012). PubMed DOI

Sherry T. W. Comparative Dietary Ecology of Sympatric, Insectivorous Neotropical Flycatchers (Tyrannidae). Ecological Monographs 54, 313–338 (1984).

Paijmans K. (ed. Paijmans K.) 212 pp. (National University Press, Canberra, 1976).

McAlpine J. R., Keig R. & Falls R. Climate of Papua New Guinea. CSIRO and Australian National University Press, Canberra (1983).

Sam K. & Koane B. New avian records along the elevational gradient of Mt. Wilhelm, Papua New Guinea. Bulletin of the British Ornithologists’ Club 134, 116–133 (2014).

Poulin B., Lefebvre G. & McNeil R. Characteristics of feeding guilds and variation in diets of bird species of three adjacent tropical sites. Biotropica 26, 187–197 (1994).

Poulin B. & Lefebvre G. t. Additional Information on the Use of Tartar Emetic in Determining the Diet of Tropical Birds. The Condor 97, 897–902 (1995).

Poulin B., Lefebvre G. t. & McNeil R. Effect and Efficiency of Tartar Emetic in Determining the Diet of Tropical Land Birds. The Condor 96, 98–104 (1994).

Ralph C., Nagata S. & Ralph J. Analysis of Droppings to Describe Diets of Small Birds. Journal of Field Ornithology 56, 165–174 (1985).

Tatner P. The diet of urban Magpies Pica pica. Ibis 125, 97–107 (1983).

Hodar J. A. The use of regression equations for estimation of prey length and biomass in diet studies of insectivore vertebrates. Miscelania Zoologica 20 (1997).

Calvemr C. & Woolledd D. A technique for assessing the taxa, length, dry weight and energy content of the arthropod prey of birds. Australian Wildlife Research 9, 293–301 (1982).

Diaz J. A. & Diaz M. Estimas de tamaños y biomasas de artrópodos aplicables al estudio de la alimentación de vertebrados insectívoros. Doñana Acta Vertebratologia 17, 67–74 (1990).

Paton D. The significance of pollen in the diet of the New Holland Honeyeater, Phylidonyris novaehollandiae (Aves: Meliphagidae). Australian Journal of Zoology 29, 217–224 (1981).

Camera traps unable to determine whether plasticine models of caterpillars reliably measure bird predation

Phylogenetic structure of moth communities (Geometridae, Lepidoptera) along a complete rainforest elevational gradient in Papua New Guinea

Reorganization of bird communities along a rainforest elevation gradient during a strong El Niño event in Papua New Guinea

Bird preferences for fruit size, but not color, vary in accordance with fruit traits along a tropical elevational gradient

Specific gut bacterial responses to natural diets of tropical birds

Species-specific but not phylosymbiotic gut microbiomes of New Guinean passerine birds are shaped by diet and flight-associated gut modifications

Biomass, abundances, and abundance and geographical range size relationship of birds along a rainforest elevational gradient in Papua New Guinea

Last Glacial Maximum led to community-wide population expansion in a montane songbird radiation in highland Papua New Guinea

Diet specialization and brood parasitism in cuckoo species

Comparative Analyses of the Digestive Tract Microbiota of New Guinean Passerine Birds