Occupancy patterns and upper range limits of lowland Bornean birds along an elevational gradient

Aim: The traditional view of species’ distributions is that they are less abundant near the edges of their ranges and more abundant toward the center. Testing this pattern is difficult because of the complexity of distributions across wide geographical areas. An alternative strategy, however, is to measure species’ distributional patterns along elevational gradients. We applied this strategy to examine whether lowland forest birds are indeed less common near their upper range limits on a Bornean mountain, and tested co-occurrence patterns among species for potential causes of attenuation, including signatures of habitat selection and competition at the periphery of their ranges.

Location: Mt. Mulu, Borneo

Taxon: Rain forest birds Methods: We surveyed lowland forest birds on Mt. Mulu (2,376 m), classified their elevation-occupancy distributions using Huisman – Olff – Fresco (HOF) models, and examined co-occurrence patterns of species pairs for signatures of shared habitat patches a...,
Presence/absence of bird species on Mt. Mulu

Presence/absence (1/0) records of lowland and montane bird species on Mt. Mulu in Borneo. Only species detected at >=10 point count locations are included. Rows are species scientific names, and columns are point count location names on Mt. Mulu. Point count lat, lon (WGS 84), and elevation (m) are available in a separate file. These data were used to plot HOF curves (for the lowland species), and to test for significantly co-occurring pairs.

Mulu_birdspecies_presence.txt

Point count location information

This gives latitude and longitude (WGS 84) and elevation (m) information about point count locations for which species are listed in the previous file. All from Mt. Mulu, Sarawak, Borneo. Files are linked by the point names field (rows in this column). 'Unkn' values for lat lon are unknown because GPS wasn't working those days, but near other points at a given elevation.

point_information_Mulu.txt

, See article