It is prevalent to use ecological niche models in the analysis of species expansion and niche changes. However, it is difficult to estimate the niche when alien species fail to establish in exotic areas. Here, we applied the tolerance niche concept, which means that niche of species can live and grow but preclude a species from establishing self‐sustaining populations, in such fail‐to‐establish events. Taking the rapidly expanded bird, Asian openbill (Anastomus oscitans), as a model species, we investigated niche dynamics and its potential effects on the population by Niche A and ecospat, predicted potential distribution by biomod2. Results showed that niche expansion has occurred in two non‐native populations caused by the tolerance of colder and wetter environments, and potential distribution mainly concentrated on equatorial islands. Our study suggested that the expanded niche belongs to tolerance niche concept according to the populations' dynamics and GPS tracking evidence. It is essential to consider source populations when we analyze the alien species. We recommended more consideration to the application of tolerance niche in alien species research, and there is still a need for standard measurement frameworks for analyzing the tolerance niche.

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.

Aim: Understanding the tolerance niches of species plays an important role in studying the mechanisms of species dispersal and invasion. Taking the rapid dispersal bird, Asian openbill (Anastomus oscitans), as a model species, we identified ecological niche changes in the process of its dispersal, explored the potential distribution, and evaluated population evolution trends. Location: East Asia, South Asia, Australia. Methods: We used the ecological niche models Niche A and ecospat to compare the spatiotemporal change in the observed niche of Asian openbill, divided into original native, China, Malay Peninsula, and present distributions. Moreover, several models were generated using a biomod2 ensemble modeling framework to predict the trends and potential distribution of species. Results: The observed niche of Asian openbill was stable between the original native and present distributions. The Malay Peninsula population represented significant niche conservatism and propagable climate conditions. The rate of niche expansion reached 77.61% among the population in China, which was able to tolerate colder temperatures than the native population. Models indicated that Asian openbill dispersal was more suitable at low latitudes. According to the best performing model, Random Forest, the distribution probabilities of the China and Malay Peninsula populations were much higher than random expectations. Main conclusions: We concluded that the novel tolerance niche during northward dispersal exceeded the native observed niche, which should not be neglected because of the cold temperature tolerance for the evolution of the species in the future. In addition, northward and southward dispersal corridors have opened and the possibility of reproduction in the southward population was higher than the northward population. Asian openbill dispersal behavior will continue both north and south, but multiple factors affect dispersal rate and durability, and the model results require more fundamental data on the source and new southern populations.

The global outbreak of the COVID-19 pandemic in 2019 led many countries to implement lockdown policies, providing a unique opportunity to study the behavioral response mechanisms of animals to human activity disturbances. The Crested Ibis (Nipponia nippon), as a typical human-associated species, is highly sensitive to changes in the intensity of human activities. To investigate the impact of the COVID-19 pandemic on the behavior of Crested Ibis, this study used alert distance and flight initiation distance as indicators to examine wild Crested Ibis populations in Yang County and surrounding areas of Hanzhong City, Shaanxi Province, before the pandemic (2013 and 2018), during the pandemic (2021), and after the pandemic (2023 and 2025). The results showed that: (1) Before the pandemic, there was no significant difference in alert distance and flight initiation distance of Crested Ibis (2013 vs. 2018, P > 0.05); (2) During the pandemic, the flight initiation distance of Crested Ibis was significantly shorter than before the pandemic (P < 0.05), but alert distance did not decrease significantly (P > 0.05); (3) After the lockdown was lifted, both alert distance and flight initiation distance of Crested Ibis were significantly lower than during the pandemic (P < 0.05) and tended to stabilize (2023 vs. 2025, P > 0.05). The study indicates that the behavioral tolerance of Crested Ibis to human activities remained stable before the pandemic, increased significantly during the pandemic, and maintained a new stable state at a higher level after the pandemic compared to before, with no rebound observed. This finding reveals significant plasticity in the behavioral response of Crested Ibis to human disturbance and can provide an important case study for understanding the behavioral adaptation strategies of wildlife under sudden public events.