Dataset

WWF survey of the entire range of the Indus River dolphin - 2001

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Original provider: Gill Braulik, WWF-Pakistan Dataset credits: Gill Braulik, WWF-Pakistan Abstract: A survey was conducted in March and April 2001, to assess the status of the Indus River dolphin, Platanista gangetica minor, throughout its present range. A total of 1535 km of survey effort was conducted, consisting of 1375 km of the Indus River main channel, 136 km of Indus River secondary channels, and 24 km of the Panjnad River, a tributary of the Indus. The effective range of the Indus dolphin has declined by 80% since 1870. The sum of best group size estimates produced an abundance estimate of 965 dolphins. Extrapolation of encounter rates to unsurveyed channels and application of a correction factor to account for missed dolphins indicates that the metapopulation may number approximately 1,200 individuals. Dolphins occur in five subpopulations separated by irrigation barrages. A pronounced increase in dolphin abundance and encounter rate was observed in each subsequent downstream subpopulation (except the last). The three largest subpopulations were between Chashma and Taunsa. Barrages (84 dolphins; 0.28/km), Taunsa and Guddu Barrages (259 dolphins; 0.74/km) and Guddu and Sukkur Barrages (602 dolphins; 3.60/km). Reasons suggested for the high encounter rate between Guddu and Sukkur Barrages, include high carrying capacity, low levels of anthropogenic threat, effective conservation, and augmentation of the subpopulation by downstream migration of dolphins from upstream.

Citation: Braulik, G. 2012. WWF survey of the entire range of the Indus River dolphin - 2001. Version 1.0.0. Dataset published in OBIS-SEAMAP. https://doi.org/10.82144/7ee03437.

Published: October 08, 2025 at 00:30

URL: http://ipt.env.duke.edu/resource?r=zd_848

Gill Braulik
WWF-Pakistan

364
occurrence records
1
taxa
1
species

Taxa

Missing and invalid fields

Field Missing Invalid
coordinateUncertaintyInMeters 364
100.0%
maximumDepthInMeters 364
100.0%
minimumDepthInMeters 364
100.0%

Quality flags

The OBIS data quality flags are documented at https://github.com/iobis/obis-qc.

Flag Dropped Records
MARINE_UNSURE 364
100.0%
NO_DEPTH 364
100.0%
ON_LAND 364
100.0%

Measurement types

DNA derived data