Seabird populations face escalating threats from the intensifying impact of hurricanes, amplified by climate change, reveals a recent study. The study, published in Nature, delves into the aftermath of Cyclone Ilsa, which ravaged Bedout Island in Western Australia in April 2023.
Cyclone Ilsa, classified as a category 5 tropical cyclone, inflicted devastating losses, wiping out approximately 80% to 90% of seabirds—equivalent to at least 20,000 breeding and nesting individuals on the island. Researchers warn that the escalating frequency and intensity of such cyclones pose significant challenges to seabird species’ ecosystem and community recovery.
Dr. Jennifer Lavers, the lead researcher, underscores the concerning trend, emphasizing the uncertainty surrounding wildlife populations’ ability to withstand such catastrophic mortality rates. With climate change driving an uptick in cyclone frequency and intensity, seabird populations face mounting pressures, exacerbating existing declines and threats.
Through aerial and ground surveys conducted from April to July 2023, researchers assessed the impact on three seabird species: the brown booby (Sula leucogaster), the lesser frigatebird (Fregata ariel), and the endemic masked booby subspecies (Sula dactylatra bedouti). The findings underscore the direct and multifaceted effects of tropical cyclones on seabirds, ranging from substantial mortality to disruption of nesting and breeding behaviors and alterations in migration patterns.
While the destructive consequences of tropical cyclones extend beyond seabird populations, Dr. Lavers highlights the critical concern regarding seabird populations reaching a tipping point where recovery becomes increasingly challenging. With cyclones striking Bedout Island approximately every seven years on average in recent decades, the frequency and intensity of these storms are approaching thresholds that seabird populations may struggle to overcome.
Over the past 15 years, Bedout Island has endured three major tropical cyclones—Cyclone George in 2007, Cyclone Stan in 2016, and Cyclone Ilsa in 2023—underscoring the recurrent threat posed to seabird habitats and ecosystems. Seabirds play a vital role as “ecosystem engineers,” and their depletion can trigger significant changes in island habitats and species dynamics, further complicating recovery efforts.
As climate-driven shifts continue to amplify the frequency and intensity of hurricanes, the vulnerability of seabird populations escalates, necessitating urgent conservation actions and adaptive strategies to mitigate the impact of extreme weather events. The study serves as a stark reminder of the intricate interplay between climate change, natural disasters, and biodiversity loss, underscoring the urgent need for concerted efforts to safeguard vulnerable ecosystems and species in the face of escalating environmental challenges.
