Coming down from the trees: is terrestrial activity in Bornean orangutans natural or disturbance driven?

The orangutan is the world's largest arboreal mammal, and images of the red ape moving through the tropical forest canopy symbolise its typical arboreal behaviour. Records of terrestrial behaviour are scarce and often associated with habitat disturbance. We conducted a large-scale species-level analysis of ground-based camera-trapping data to evaluate the extent to which Bornean orangutans Pongo pygmaeus come down from the trees to travel terrestrially, and whether they are indeed forced to the ground primarily by anthropogenic forest disturbances. Although the degree of forest disturbance and canopy gap size influenced terrestriality, orangutans were recorded on the ground as frequently in heavily degraded habitats as in primary forests. Furthermore, all age-sex classes were recorded on the ground (flanged males more often). This suggests that terrestrial locomotion is part of the Bornean orangutan's natural behavioural repertoire to a much greater extent than previously thought, and is only modified by habitat disturbance. The capacity of orangutans to come down from the trees may increase their ability to cope with at least smaller-scale forest fragmentation, and to cross moderately open spaces in mosaic landscapes, although the extent of this versatility remains to be investigated

Coming down from the trees: is terrestrial activity in Bornean orangutans natural or disturbance driven?

The orangutan is the world's largest arboreal mammal, and images of the red ape moving through the tropical forest canopy symbolise its typical arboreal behaviour. Records of terrestrial behaviour are scarce and often associated with habitat disturbance. We conducted a large-scale species-level analysis of ground-based camera-trapping data to evaluate the extent to which Bornean orangutans Pongo pygmaeus come down from the trees to travel terrestrially, and whether they are indeed forced to the ground primarily by anthropogenic forest disturbances. Although the degree of forest disturbance and canopy gap size influenced terrestriality, orangutans were recorded on the ground as frequently in heavily degraded habitats as in primary forests. Furthermore, all age-sex classes were recorded on the ground (flanged males more often). This suggests that terrestrial locomotion is part of the Bornean orangutan's natural behavioural repertoire to a much greater extent than previously thought, and is only modified by habitat disturbance. The capacity of orangutans to come down from the trees may increase their ability to cope with at least smaller-scale forest fragmentation, and to cross moderately open spaces in mosaic landscapes, although the extent of this versatility remains to be investigated

BEDMAP2 - Ice thickness, bed and surface elevation for Antarctica - standardised data points

We present here the Bedmap2 ice thickness, bed and surface elevation standardised CSV data points that were used to create the Bedmap2 gridding products. The data consists of 25 million points coming from 68 individual surveys acquired in Antarctica. The associated datasets consist of: - Bedmap1 standardised CSV data points: https://doi.org/10.5285/f64815ec-4077-4432-9f55-0ce230f46029 - Bedmap3 standardised CSV data points: https://doi.org/10.5285/91523ff9-d621-46b3-87f7-ffb6efcd1847 - Bedmap2 statistically-summarised data points (shapefiles): https://doi.org/10.5285/0f90d926-99ce-43c9-b536-0c7791d1728b - Bedmap2 gridding products: https://doi.org/10.5285/fa5d606c-dc95-47ee-9016-7a82e446f2f2 This work is supported by the SCAR Bedmap project and the British Antarctic Survey's core programme: National Capability - Polar Expertise Supporting UK Researc

BEDMAP2 - Ice thickness, bed and surface elevation for Antarctica - standardised data points

We present here the Bedmap2 ice thickness, bed and surface elevation standardised CSV data points that were used to create the Bedmap2 gridding products. The data consists of 25 million points coming from 68 individual surveys acquired in Antarctica. The associated datasets consist of: - Bedmap1 standardised CSV data points: https://doi.org/10.5285/f64815ec-4077-4432-9f55-0ce230f46029 - Bedmap3 standardised CSV data points: https://doi.org/10.5285/91523ff9-d621-46b3-87f7-ffb6efcd1847 - Bedmap2 statistically-summarised data points (shapefiles): https://doi.org/10.5285/0f90d926-99ce-43c9-b536-0c7791d1728b - Bedmap2 gridding products: https://doi.org/10.5285/fa5d606c-dc95-47ee-9016-7a82e446f2f2 This work is supported by the SCAR Bedmap project and the British Antarctic Survey's core programme: National Capability - Polar Expertise Supporting UK Researc

BEDMAP2 - Ice thickness, bed and surface elevation for Antarctica - standardised shapefiles and geopackages

We present here the Bedmap2 ice thickness, bed and surface elevation aggregated points and survey lines. The aggregated points consist of statistically-summarised shapefile points (centred on a continent-wide 500 m x 500 m grid) that reports the average values of ice thickness, bed and surface elevation from the full-resolution survey data and information on their distribution. The points presented here correspond to the additional points to Bedmap1 used for the gridding of Bedmap2. The data comes from 14 different data providers and 75 individual surveys. They are available as geopackages and shapefiles. The associated datasets consist of: - Bedmap1 statistically-summarised data points (shapefiles): https://doi.org/10.5285/925ac4ec-2a9d-461a-bfaa-6314eb0888c8 - Bedmap3 statistically-summarised data points (shapefiles): https://doi.org/10.5285/a72a50c6-a829-4e12-9f9a-5a683a1acc4a - Bedmap2 standardised CSV data points: https://doi.org/10.5285/2fd95199-365e-4da1-ae26-3b6d48b3e6ac - Bedmap2 gridding products: https://doi.org/10.5285/fa5d606c-dc95-47ee-9016-7a82e446f2f2 This work is supported by the SCAR Bedmap project and the British Antarctic Survey's core programme: National Capability - Polar Expertise Supporting UK Researc

BEDMAP2 - Ice thickness, bed and surface elevation for Antarctica - gridding products

We present here Bedmap2 (2013), a suite of gridded products describing surface elevation, ice-thickness and the sea floor and subglacial bed elevation of the Antarctic south of 60deg S. We derived these products using data from a variety of sources, including many substantial surveys completed since the original Bedmap compilation (Bedmap1) in 2001. In particular, the Bedmap2 ice thickness grid is made from 25 million measurements, over two orders of magnitude more than were used in Bedmap1. In most parts of Antarctica the subglacial landscape is visible in much greater detail than was previously available and the improved data coverage has in many areas revealed the full scale of mountain ranges, valleys, basins and troughs, only fragments of which were previously indicated in local surveys. The derived statistics for Bedmap2 show that the volume of ice contained in the Antarctic ice sheet (27 million km3) and its potential contribution to sea-level rise (58 m) are similar to those of Bedmap1, but the mean thickness of the ice sheet is 4.6 % greater, the mean depth of the bed beneath the grounded ice sheet is 72 m lower and the area of ice sheet grounded on bed below sea level is increased by 10 %. The Bedmap2 compilation highlights several areas beneath the ice sheet where the bed elevation is substantially lower than the deepest bed indicated by Bedmap1. These products, along with grids of data coverage and uncertainty, provide new opportunities for detailed modelling of the past and future evolution of the Antarctic ice sheets. The compilation of Bedmap2 products was undertaken within the British Antarctic Survey's programme, Polar Science for Planet Earth

BEDMAP2 - Ice thickness, bed and surface elevation for Antarctica - gridding products

We present here Bedmap2 (2013), a suite of gridded products describing surface elevation, ice-thickness and the sea floor and subglacial bed elevation of the Antarctic south of 60deg S. We derived these products using data from a variety of sources, including many substantial surveys completed since the original Bedmap compilation (Bedmap1) in 2001. In particular, the Bedmap2 ice thickness grid is made from 25 million measurements, over two orders of magnitude more than were used in Bedmap1. In most parts of Antarctica the subglacial landscape is visible in much greater detail than was previously available and the improved data coverage has in many areas revealed the full scale of mountain ranges, valleys, basins and troughs, only fragments of which were previously indicated in local surveys. The derived statistics for Bedmap2 show that the volume of ice contained in the Antarctic ice sheet (27 million km3) and its potential contribution to sea-level rise (58 m) are similar to those of Bedmap1, but the mean thickness of the ice sheet is 4.6 % greater, the mean depth of the bed beneath the grounded ice sheet is 72 m lower and the area of ice sheet grounded on bed below sea level is increased by 10 %. The Bedmap2 compilation highlights several areas beneath the ice sheet where the bed elevation is substantially lower than the deepest bed indicated by Bedmap1. These products, along with grids of data coverage and uncertainty, provide new opportunities for detailed modelling of the past and future evolution of the Antarctic ice sheets. The compilation of Bedmap2 products was undertaken within the British Antarctic Survey's programme, Polar Science for Planet Earth