Quitian, M.; Santillan, V.; Espinosa, C.I.; Homeier, J.; Boehning-Gaese, K.; Schleuning, M. & Neuschulz, E. (2017): <b>Elevation-dependent effects of forest fragmentation on plant–bird interaction networks in the tropical Andes</b>. <i>Ecography</i> <b>40</b>, 1-10.
Resource Description
Title:
Elevation-dependent effects of forest fragmentation on plant–bird interaction networks in the tropical Andes
FOR816dw ID:
1704
Publication Date:
2017-11-08
License and Usage Rights:
Resource Owner(s):
Individual:
Marta Quitian
Contact:
email:
marta.quitian <at> senckenberg.de
Senckenberganlage 25
60325 Frankfurt am Main
Germany
Individual:
Vinicio Santillan
Contact:
email:
Vinicio.Santillan <at> senckenberg.de
Senckenberganlage 25
60325 Frankfurt am Main
Germany
Individual:
Carlos Iván Espinosa
Contact:
email:
webmaster <at> tropicalmountainforest.org
Individual:
Jürgen Homeier
Contact:
email:
jhomeie <at> gwdg.de
Faculty of Resource Management
University of Applied Sciences and Arts (HAWK)
37077 Göttingen
Germany
Individual:
Katrin Boehning-Gaese
Contact:
email:
katrin.boehning-gaese <at> senckenberg.de
Senckenberganlage 25
60325 Frankfurt am Main
Senckenberganlage 25
Germany
Individual:
Matthias Schleuning
Contact:
email:
webmaster <at> tropicalmountainforest.org
Individual:
Eike-Lena Neuschulz
Contact:
email:
elneuschulz <at> senckenberg.de
Senckenberganlage 25
60325 Frankfurt am Main
Germany
Abstract:
Tropical forests harbor diverse ecological communities of plants and animals that are organized in complex interaction networks. The diversity and structure of plant–animal interaction networks may change along elevational gradients and in response to human-induced habitat fragmentation. While previous studies have analyzed the effects of elevation and forest fragmentation on species interaction networks in isolation, to our knowledge no study has investigated whether the effects of forest fragmentation on species interactions may differ along elevational gradients. In this study, we analyzed main and interaction effects of elevation and forest fragmentation on plant–frugivore interaction networks at plant and bird species level. Over a period spanning two years, we recorded plant–frugivore interactions at three elevations (1000, 2000 and 3000 m a.s.l.) and in two habitat types (continuous and fragmented forest) in tropical montane forests in southern Ecuador. We found a consistent effect of elevation on the structure of plant–frugivore networks. We observed a decrease in the number of effective bird partners of plants and, thus, a decline in the redundancy of bird species with increasing elevation. Furthermore, bird specialization on specific plant partners increased towards high elevations. Fragmentation had a relatively weak effect on the interaction networks for both plant and bird species, but resulted in a significant increase in bird specialization in fragmented forests at high elevations. Our results indicate that forest fragmentation may have stronger effects on plant–frugivore interaction networks at high compared to low elevations because bird species richness declined more steeply towards high elevations than plant species richness. We conclude that conservation efforts should prioritize the maintenance of consumer diversity, for instance by maintaining stretches of continuous forest. This applies in particular to species-poor communities, such as those at high elevations, as the ecological processes in these communities seem most sensitive towards forest fragmentation.
