Short-tailed Shearwaters
Short-tailed shearwaters are native to New Zealand, they’re migratory birds that are often seen off the coast of mainland NZ. It’s estimated that the population is about 23 million birds so they’re not considered endangered (although their numbers are dropping due to climate change) but they were far more common in the eighteenth century when there were flocks of over 100 million birds.
What do we like about them?
Short-tailed shearwaters migrate annually, travelling all the way from their breeding grounds off the south coast of Australia to the Arctic Ocean, it’s a huge trip of around 15,000 km each way!
Short-tailed shearwaters and balloons
Short-tailed shearwaters actively choose to eat balloons because they float on the water and look like one of their favourite foods: squid. In seabirds ingesting balloons or even just balloon fragments is lethal - birds like the short-tailed shearwater are 32 times more likely to die if they eat balloons than if they eat hard plastic fragments.
References
https://www.nzbirdsonline.org.nz/species/short-tailed-shearwater
Heidi Acampora, Qamar A. Schuyler, Kathy A. Townsend, Britta Denise Hardesty,
Comparing plastic ingestion in juvenile and adult stranded short-tailed shearwaters (Puffinus tenuirostris) in eastern Australia, Marine Pollution Bulletin, Volume 78, Issues 1–2, 2014, Pages 63-68
Lauren Roman, Britta Denise Hardesty, Mark A. Hindell, & Chris Wilcox, A quantitative analysis linking seabird mortality and marine debris ingestion. Scientific Reports | (2019) 9:3202 | https://doi.org/10.1038/s41598-018-36585-9