Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-15T09:19:54.864Z Has data issue: false hasContentIssue false

Nest building by Darwin’s finches as an overlooked seed dispersal mechanism

Published online by Cambridge University Press:  11 December 2018

Carlos Camacho
Affiliation:
Department of Evolutionary Ecology, Estación Biológica de Doñana – CSIC, Av. Américo Vespucio 26, 41092 Seville, Spain
Marc-Olivier Beausoleil*
Affiliation:
Department of Biology and Redpath Museum, McGill University, 859 Sherbrooke Street West, Montreal, Quebec, Canada H3A 2K6
Julio Rabadán-González
Affiliation:
Observado.es, Gordal 8, 41940 Tomares, Seville, Spain
Roxanne Richard
Affiliation:
Department of Biology and Redpath Museum, McGill University, 859 Sherbrooke Street West, Montreal, Quebec, Canada H3A 2K6

Abstract

Caliochory, or seed dispersal by birds as nest material, has been reported for several species, but its effectiveness remains unclear in most cases. Darwin’s finches are traditionally regarded as seed predators, but the observation of two nests challenges this assumption by demonstrating that they can act as seed dispersers via caliochory. Darwin’s finches incorporate cotton-like materials into their nests, including seeds of Darwin’s cotton (Gossypium darwinii), a shrub endemic to the Galápagos (Ecuador). Bird nests typically break down after intense rainfall, so the seeds incorporated into nests might benefit from suitable conditions for germination. By simulating the germination conditions experienced over a 72-h period by cotton seeds in a naturally fallen nest, this study qualitatively confirms the long-term viability of at least a small fraction of the seeds at the surface of the nest. Darwin’s finches might therefore provide seed-dispersal services to Darwin’s cotton and possibly, other native and exotic plants of the Galápagos commonly incorporated into nests. However, larger confirmatory studies are needed.

Type
Short Communication
Copyright
© Cambridge University Press 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature cited

Damschen, EI, Baker, DV, Bohrer, G, Nathan, R, Orrock, JL, Turner, JR, Brudvig, LA, Haddad, NM, Levey, DJ and JJ, Tewksbury (2014) How fragmentation and corridors affect wind dynamics and seed dispersal in open habitats. Proceedings of the National Academy of Sciences 111, 34843489.CrossRefGoogle ScholarPubMed
Darwin, C (1859) On the Origin of Species by Means of Natural Selection or the Preservation of Favoured Races in the Struggle for Life. London: J. Murray, 513 pp.Google Scholar
Dean, WRJ and Milton, SJ (1991) Galium tomentosum – a yarn for the birds. Veld and Flora 77, 8283.Google Scholar
Dean, WRJ, Milton, SJ and Siegfried, WR (1990) Dispersal of seeds as nest material by birds in semiarid Karoo shrubland. Ecology 71, 12991306.CrossRefGoogle Scholar
Fedriani, JM, Garrote, PJ, Delgado, MM and Penteriani, V (2015) Subtle gardeners: inland predators enrich local topsoils and enhance plant growth. PLoS ONE 10, e0138273.CrossRefGoogle ScholarPubMed
Grant, PR and Boag, PT (1980) Rainfall on the Galápagos and the demography of Darwin’s finches. The Auk 97, 227244.Google Scholar
Guerrero, AM and Tye, A (2009) Darwin’s finches as seed predators and dispersers. Wilson Journal of Ornithology 121, 752764.CrossRefGoogle Scholar
Hutchinson, JB, Silow, RA and Stephens, SG (1947) The Evolution of Gossypium and the Differentiation of the Cultivated Cottons. London: Oxford University Press, 160 pp.Google Scholar
Knutie, SA, McNew, SM, Bartlow, AW, Vargas, DA and Clayton, DH (2014) Darwin’s finches combat introduced nest parasites with fumigated cotton. Current Biology 24, R355R356.CrossRefGoogle ScholarPubMed
Lack, D (1947) Darwin’s Finches. Cambridge: Cambridge University Press, 208 pp.Google Scholar
McMullen, CK (1999) Flowering Plants of the Galápagos. Ithaca: Cornell University Press, 370 pp.Google Scholar
Orr, RT (1945) A study of captive Galápagos finches of the genus Geospiza. The Condor 47, 177201.CrossRefGoogle Scholar
Ridley, HN (1930) The Dispersal of Plants Throughout the World. Ashford: L. Reeve & Company, 744 pp.Google Scholar
Rohwer, VG, Pauw, A and Martin, PR (2017) Fluff-thieving birds sabotage seed dispersal. Royal Society Open Science 4, 160538.CrossRefGoogle ScholarPubMed
Sliwinska, E and Bewley, JD (2014) Overview of seed development, anatomy and morphology. In Gallagher, RS (ed.), Seeds: The Ecology of Regeneration in Plant Communities. Wallingford: CABI, pp. 117.Google Scholar
Stephens, SG and Rick, CM (1966) Problems on the origin, dispersal, and establishment of the Galápagos cottons. In Bowman, RI (ed.), The Galápagos: Proceedings of the Symposia of the Galápagos International Scientific Project. Los Angeles: University of California Press, pp. 201208.Google Scholar
Warren, RJ, Love, JP and Bradford, MA (2017) Nest-mediated seed dispersal. Plant Ecology 218, 12131220.CrossRefGoogle Scholar

Camacho et al. supplementary material

Camacho et al. supplementary material 1

Download Camacho et al. supplementary material(Video)
Video 171.1 MB