Wetland Transformation and Waterfowl Decline: Linking Habitat Change to Northern Pintail Losses in Punjab

Vast number of migratory bird species rely on wetlands of Punjab Pakistan during tough wintering season. Most spectacular of these winter visitors are waterbirds including Northern pintail(Anas acuta). This study investigates the trends in Northern Pintail abundance and their correlation with wetland habitat conditions focusing on spatial and temporal shifts on longitudinal scale (2015-2025). We examine the complex interplay between rainfall variability, water quality and vegetation health to track habitat changes and their impact on Pintail populations. Northern Pintail populations were monitored through systematic boat-based and point-count surveys conducted across designated wetland sites. Long-term population trends were evaluated using the non-parametric Mann-Kendall trend test, complemented by Sen's slope estimators to quantify the direction and magnitude of temporal changes in abundance. To assess the influence of environmental variables on Pintail population dynamics, Generalized Linear Mixed Models (GLMMs) were employed. Availability of water, vegetation pattern(Measured by NDVI) and rainfall pattern in particular region were taken as predictor variables. Population census data collected on yearly basis revealed a sharp decrease of Northern Pintails, with net declines exceeding 99% at both Namal Lake (99.04%) and Uchali Lake (99.19%). Average reduction in Northern Pintail numbers remained 98.34% across all the wetlands under study. Analysis of Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) values identified the primary driver of this decline as extensive vegetation loss, which compromises the availability of food and shelter critical to the species' survival. Results of current study highlights that the presence of water alone is insufficient to sustain viable waterbird populations; instead, the structural quality of vegetative habitat was acting as a limiting factor. The findings point to habitat degradation as a key contributor to the ongoing ecological crisis facing waterbirds in the region. Consequently, effective conservation strategies must go beyond hydrological interventions and focus on restoring and maintaining the ecological integrity of wetland habitats to reduce further biodiversity loss.