A theoretical framework for understanding the ecology and conservation of bamboo-specialist birds

Nestedness and Patch Size of Bamboo-Specialist Bird Communities in Southeastern Peru

“…Because single bamboo patches do not provide long-term habitat for most specialists, these species may require intact landscapes at the vast spatial scales on which bamboo cycles operate. This point that has been made by Areta and Cockle (2012) in the context of nomadic granivorous bamboo specialists that follow the masting of bamboo, and it is equally true of the sedentary insectivores. The disappearance of most taxa after a die-off confirms the importance of successful dispersal for the viability of these species.…”

Assessing bird migrations

“…In the Brazilian Cerrado, yearly fire events trigger the irruptive migrations of a number of tall-grass irruptive taxa, whose migrations are more pronounced around every three years when dry biomass is extremely abundant and the burned areas are more extensive (Pereira & Gama 2010). Another group of irruptive migrants are the insectivorous bamboo-specialists of tropical forests that inhabit the same bamboo patch for many years at a time and irrupt to find new habitat when the patch dies off (Budke et al 2010;Areta & Cockle 2012).…”

“…Nevertheless, nomadic taxa are also present in ecosystems of high productivity. For example, bamboo-seed-specialist birds move nomadically in response to masting and die-off cycles of massflowering bamboos in the rainforests of the Americas, Asia, Oceania and Africa -but are different from the irruptive insectivorous bamboo-specialists, which inhabit bamboo patches for longer periods during their vegetative growth (Areta & Cockle 2012). These masting events take place at large intervals of time (from 3 to 120 years) for each plant and only happen for a few months or years at a time.…”

“…However, the spatio-temporal occurrence of seeding is stochastic because the cycles of individual plants are not synchronised, thus some bamboo-seed-specialist birds periodically search nomadically for bamboo patches with enough resources. For example, in South America the Purple-winged ground-dove Claravis geoffroyi, the Temminck's seedeater Sporophila falcirostris and the Buff-fronted seedeater S. frontalis are associated with masting of the two common native Guadua bamboos G. trinii and G. chacoensis (Areta et al 2009;Areta & Cockle 2012). In East Africa, the Magpie mannikin Spermestes fringilloides relies on seeds of the Bindura bamboo Oxytenanthera abyssinica, which produces seeds approximately every 30 years, in some locations for up to seven years, and these birds move elsewhere when few bamboo seeds remain (Areta et al 2009).…”

“…An example of a landbird is the Northern wheatear Oenanthe oenanthe, whose breeding range is spread over most of Eurasia and North America and the entire population spends the boreal winter in a smaller area in central Africa(Bairlein et al 2012;Blackburn & Cresswell 2016). -Irruptive dispersive (Id): Several taxa of insectivorous bamboo-specialists that inhabit the tropical forests of the Americas, Asia, Oceania and Africa(Areta & Cockle 2012) show this movement type.These are distinct from the more dynamic and stochastic movements of seed bamboo-specialist nomadic birds, which depend on the resources available during relatively shorter masting periods before bamboo patches die. The insectivorous bamboo-specialists inhabit bamboo patches during their vegetative growth phase(Budke et al 2010).…”