Satellite telemetry tracks flyways of Asian Openbill storks in relation to H5N1 avian influenza spread and ecological change

Abstract

BackgroundAsian Openbills, Anastomus oscitans, have long been known to migrate from South to Southeast Asia for breeding and nesting. In Thailand, the first outbreak of H5N1 highly pathogenic avian influenza (HPAI) infection in the Openbills coincided with the outbreak in the poultry. Therefore, the flyways of Asian Openbills was determined to study their role in the spread of H5N1 HPAI virus to poultry and wild birds, and also within their flocks.ResultsFlyways of 5 Openbills from 3 colonies were monitored using Argos satellite transmitters with positioning by Google Earth Programme between 2007 and 2013. None of the Openbills tagged with satellite telemeters moved outside of Thailand. Their home ranges or movement areas varied from 1.6 to 23,608 km2 per month (95% utility distribution). There was no positive result of the viral infection from oral and cloacal swabs of the Openbills and wild birds living in the vicinity by viral isolation and genome detection during 2007 to 2010 whereas the specific antibody was not detected on both Openbills and wild birds by using microneutralization assay after 2008. The movement of these Openbills did not correlate with H5N1 HPAI outbreaks in domestic poultry but correlated with rice crop rotation and populations of the apple snails which are their preferred food. Viral spread within the flocks of Openbills was not detected.ConclusionsThis study showed that Openbills played no role in the spread of H5N1 HPAI virus, which was probably due to the very low prevalence of the virus during the monitoring period. This study revealed the ecological factors that control the life cycle of Asian Openbills.Electronic supplementary materialThe online version of this article (10.1186/s12917-018-1683-x) contains supplementary material, which is available to authorized users.

Breeding ecology of the Asian openbill in eastern Nepal: Larger trees support higher fledgling success

“…We observed several colonies of the Asian openbill within areas of human habitation and agricultural landscapes, similar to reports for other stork or crane species in South Asia (Katuwal, Sundar, et al., 2022 ; Kittur & Sundar, 2021 ; Sharma et al., 2024 ). This is primarily attributed to the presence of large‐sized nesting trees protected by local communities and possibly the abundance of prey species within agricultural landscapes (Hara et al., 2018 ; Pramanik et al., 2016 ; Ratanakorn et al., 2018 ; Sundar et al., 2019 ). Additionally, we observed some colonies in forests, indicating that Asian openbills also utilize diverse habitats for breeding.…”

Tolerance niche expansion and potential distribution prediction during Asian openbill bird range expansion

“…The previous study on tracking flyways of Asian openbill in Thailand reported that some individuals moved between south and central Thailand (Ratanakorn et al., 2018), even fly to northeast India and Bangladesh during the non‐breeding season (McClure, 1998). It could be argued that the “over‐migration” occurred in Thailand when the storks initially migrated north, bringing a few migrants to locations out of their regular migratory range as vagrants (Ralph & Wolfe, 2018), and arriving in southwest China.…”

“…Thailand reported that some individuals moved between south and central Thailand (Ratanakorn et al, 2018), even fly to northeast India and Bangladesh during the non-breeding season (McClure, 1998).…”