Hummingbird–Plant Interactions Are More Specialized in Forest Compared to Coffee Plantations

Abstract

Deforestation transforms habitats, displacing vertebrates and the other dimensions of biodiversity they support through their interactions. Few empirical studies have quantified the effect deforestation has on vertebrate–pollinator interaction networks. Here we quantify how hummingbird–plant networks change in relation to hummingbird diversity across a deforestation gradient. We found that, overall, hummingbird–plant interactions were significantly more specialized in forests and specialized interactions decayed rapidly with the loss of tree cover at small spatial scales. Hummingbird species interaction specialization was also higher in forest habitats compared to coffee plantations, but we found no support for a morphological hummingbird trait that predicted interaction specialization or forest dependence. Finally, we developed spatially explicit models for quantifying impacts of land-use decisions on hummingbird species and the biodiversity they support. These tools can be used to identify and prioritize important habitats for conservation activities, like creating new protected areas and improving agricultural lands for biodiversity.

Is bigger always better? Neither body size nor aggressive behavior predicts specialization of hummingbirds in a rocky outcrop

“…This specialization can be related to flower morphology (Fonseca et al., 2016; Maglianesi et al., 2014) and to hummingbird morphology (beak length) (Maglianesi et al., 2014). However, it was shown that hummingbirds relaxed their specialized relationships and became less specific in their interactions in nonforested areas (Morrison & Mendenhall, 2020). Our research was conducted in a Campo Rupestre area, where trees are rare; so, our result of a lower specialization in our interaction network was expected.…”

Testing for pollinator recognition in multiple species ofHeliconia

“…In forest fragments around Coto Brus, mismatched hummingbirds account for c.a. 10% of honest visits (those in which the visitor contacts the reproductive organs of the flower) to H. tortuosa (K. Leimburger, unpublished data ), but this proportion likely increases in isolated fragments where morphologically matched hummingbirds are less common [34–36]. The combination of fragmentation and pollinator recognition therefore has a strong ecological impact on H. tortuosa populations, which show reduced seed sets in fragmented forests compared to those in continuous forest [37], presumably due to a paucity of morphologically matched hummingbirds.…”

Is bigger always better? Neither body size nor aggressive behavior are good predictors to measure the degree of specialization of hummingbird interaction networks in rocky outcrops

“…This specialization can be related to the flower morphology (Maglianesi et al 2014, Fonseca et al 2016) and to hummingbird morphology (beak length) (Maglianesi et al 2014). However, it was shown that hummingbirds relaxed their specialized relationships and became less specific in their interactions in non-forested areas (Morrison and Mendenhall, 2020). Our research was conducted in a Campo Rupestre area, where trees are rare, reinforcing our result of a lower specialization in our interaction network.…”