Diurnal Habitat Selection and Use of Wintering Bar-Headed Geese (Anser indicus) Across Heterogeneous Landscapes on the Yunnan–Guizhou Plateau, Southwest China

TL;DR

Bar-headed Geese adjust their habitat use based on the landscape they winter in, using croplands in agricultural areas and natural grasslands in more natural wetlands.

Contribution

The study reveals region-specific diurnal habitat use patterns of Bar-headed Geese in different wetland landscapes and identifies key environmental factors influencing these patterns.

Findings

In agricultural wetlands, Bar-headed Geese primarily use croplands and marshes.

In natural wetlands, they prefer grasslands and marshes with minimal cropland use.

Environmental factors like distance to feeding sites and open water influence habitat selection differently across regions.

Abstract

This study investigated differences in diurnal habitat selection and use by wintering Bar-headed Geese across wetlands with varying landscape characteristics. Using satellite tracking data and habitat modeling, we found that the Bar-headed Goose exhibited distinct diurnal habitat use patterns among different wintering wetlands. In the agriculturally dominated wetlands of Nianhu and Caohai, geese primarily utilized croplands and marshes, while in the more natural Napahai wetland, they primarily utilized natural grasslands and marshes. These behavioral differences highlight the geese’s behavioral flexibility in adjusting to diverse landscape conditions. Our findings provide a scientific basis for developing region-specific wetland bird conservation strategies. We emphasize the need for management actions tailored to local landscape characteristics. Such actions include carefully managing supplemental feeding, preserving cropland–wetland mosaics, and optimizing water-level management to effectively conserve wintering waterbirds on plateau wetlands.

Wetland loss and human activities are forcing migratory waterbirds to rely on alternative habitats such as croplands, yet their adaptive habitat use across contrasting landscape contexts remains unclear. The Bar-headed Goose (Anser indicus) is a key indicator species in the wetland ecosystems of the Yunnan–Guizhou Plateau. Comparing differences in its wintering habitat selection and utilization is of great significance for understanding its ecological adaptation mechanisms and formulating regional wetland conservation strategies. In this study, we compared the diurnal habitat use during the wintering period of Bar-headed Geese at three wetlands (Nianhu, Caohai, and Napahai) representing distinct landscape contexts. We used GPS satellite tracking and dynamic Brownian bridge movement modeling, combined with random forest analysis of environmental variables, to quantify diurnal habitat use and selection at each site. Our results revealed significant regional differences in habitat use. In the agriculture-dominated wetlands (Nianhu and Caohai), geese primarily utilized cropland and marsh habitats (Nianhu: cropland 45.88% ± 30.70%, marsh 42.55% ± 33.17%; Caohai: cropland 62.33% ± 12.16%, marsh 28.61% ± 13.62%). In contrast, at Napahai, which is dominated by natural habitats, geese primarily used grassland (65.92% ± 20.01%) and marsh (26.85% ± 21.88%), with minimal use of cropland (4.21% ± 7.00%). Diurnal habitat selection was influenced by multiple environmental factors, with distinct regional differences identified through random forest modeling. In Nianhu, key factors included distance to supplemental feeding site, distance to grassland, distance to woodland, and distance to open water. In Caohai, distance to grassland, distance to nocturnal roost site, distance to settlement, and distance to open water were significant drivers. In Napahai, distance to nocturnal roost site, distance to open water, and distance to marsh were the most influential (all with p < 0.01), reflecting flexible behavioral responses. Based on these findings, we recommend region-specific conservation management strategies. Specifically, supplemental feeding at Nianhu should be strictly regulated. Agricultural planning in farming areas should account for the habitat needs of wintering waterbirds. Grassland and marsh habitats at Napahai should also be more effectively protected.

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