Local and regional diversity of frog communities along an extensive rainforest elevation gradient in Papua New Guinea

• Published in: Biotropica Vol. 56; no. 1; pp. 90 - 97
• Main Authors: Dahl, Chris, Richards, Stephen J., Basien, Ismale, Mungkaje, Augustine J., Novotny, Vojtech
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.01.2024
• Subjects: alpha diversity; Amphibians; Aquatic reptiles; beta diversity; Biodiversity; Biodiversity hot spots; Climate change; Community; Community composition; Composition; Dispersion; Distance; Elevation; elevation range; Environmental changes; Fauna; Frogs; Gradients; Hot spots; Microhylidae; Mountains; Rainforests; Rapoport pattern; Speciation; Species diversity; species pool; tropical forests; New Guinea; Papua New Guinea
• ISSN: 0006-3606; 1744-7429
• DOI: 10.1111/btp.13283

Rainforests on high tropical mountains are globally important species diversity hotspots. We studied amphibians along an extensive rainforest elevation gradient on Mt. Wilhelm (4509 m) in Papua New Guinea. We established eight sites at 500 m elevation increments between 200 and 3700 m a.s.l. and relate their community composition to the known species pool of New Guinea island. We recorded 3390 frogs from 55 species, which is three times more species than at any local community along the elevation gradient. Species diversity peaked at 1700 m a.s.l. for Mt. Wilhelm communities, and at 500–1100 m a.s.l. in the broader New Guinea fauna, probably reflecting increasing speciation and decreasing dispersal rates with increasing elevation. The beta diversity between frog communities was high and increased with increasing elevation. The change in frog community composition across 500 m elevation corresponded to the change over 200 km distance within lowland forests. A majority of frog species were distributed over narrow <500 m elevational ranges, at Mt Wilhelm and the New Guinea fauna more broadly. We did not detect Rapoport's pattern of wider elevation range for species at higher elevations than for lowland species, for Mt. Wilhelm communities or the New Guinea fauna. The high beta diversity patterns along elevation gradients generated by rapid species turnover with narrow elevation ranges make frog communities vulnerable to change in environment, including climate change. in Melanesian Pidgin is available with online material. Abstrak (Melanesian Pidgin) Tropikal rainforest antap long bikpela maunten i makim nambwan species diversity hotspots insait long wold. Wok painim aut bilong amphibians long rainforest elevasen igo Mt. Wilhelm (4509 m) long Papua Niugini. Mipela makim 8pela stadi eria, soim 500 m elevasen namel, statim wantaim 200 m igo moa 3700 m elevasen mak. Dispela mipela bungim igo wantaim komuniti komposisen wantaim species pool bilong Niugini Island. Mipela rekodim 3390 frogs, wei i kamapim 55 species, soim moa olsem 3 times moa yet species komperim igo long lokal komuniti insait long stadi bilong elevasenal gradient. Namba bilong species (species diversity) igo antap 1700 m a.s.l long Mt. Wihelm komuniti na namel 500–1100 m a.s.l. igo wantaim Niugini fauna, soim increasing speciasen na decreasing dispersal rates wantaim elevasen. Beta diversity namel long frog komuniti istap antap yet wantaim elevasen. Sanis stap long frog komuniti komposen long 500 m elevasen igo wantaim 200 km distance long lowland forests. Plenti moa frog species i stap insait <500 m elevasen‐range, Mt. Wilhelm na tu Niugini. Mipela ino ditetim Rapoport's patten, soim elevasen species range wantain maunten, species stap lowland, Mt Wilhelm na Niugini fauna wantaim. Beta diversity patten insait long elevasen gradients wantaim species turnover na narrow elevasen‐range makim frog komuniti vulnerable long sanis bilong enviromen na climate change. Our elevational frog study recorded three times more species diversity than any local community studied. We observed mid diversity peak in frog species. A majority of frog species had <500 m elevational range distribution. High beta diversity patterns along elevation gradients generated by rapid species turnover with narrow elevational range make frog communities vulnerable to future impact of climate change.