With New Year’s festivities just weeks away, many people are looking forward to a night of revelry punctuated by the booms, smoke and flashes of fireworks. But if you are a wild bird, that season can trigger more dread than excitement.
People pet dogs know the anxiety-provoking nature of a pyrotechnic barrage. Now, scientists have discovered the effects resonate for weeks in migratory Arctic geese overwintering in the fields of northern Europe.
Not only are the birds’ normal nighttime routines smashed by New Year’s festivities, it appears they spend more time eating for weeks afterwards in an apparent attempt to make up for the extra energy burned fleeing the fireworks. For birds, New Year’s is all hangover, no party.
“Even small amounts of fireworks will change the behaviours of geese in ways that might reduce their chances of survival, at least in severe winters,” says Bart Nolet an ecologist at the Netherlands Institute of Ecology who worked on the study.
The link between fireworks and disturbances to wildlife have been known for some time. Dutch scientists previously used radar to document hundreds of thousands of birds taking flight right around the time clocks there struck midnight on New Year’s. But such work didn’t look for long-term effects.
Nolet and his colleagues turned to GPS trackers attached to migratory geese to see if they could find any signs of prolonged effects from the fireworks. The scientists looked at the movements of 347 geese from four species that spend summers in the Arctic and winters in northern European countries such as Germany and the Netherlands.
The birds – greater white-fronted geese, bean geese, barnacle geese and pink-footed geese – were outfitted with GPS transmitters mounted to either neckbands or tiny backpacks. The units enabled scientists to compare how the birds acted before, during and after New Year’s over eight recent winters.
The data showed that New Year’s celebrations were upsetting the birds’ routines, prompting them to change location more often and alter their flight patterns. The geese on average flew 5 to 16 kilometers further and 40 to 150 meters higher around New Year’s eve than in the preceding dozen days, the researchers reported in late November in the journal Conservation Letters.
“It’s shocking to see just how much further birds fly on nights with fireworks compared to other nights,” said Andrea Kölzsch, a scientist at Germany’s Max Planck Institute of Animal Behavior who led the research. “Some individuals flew hundreds of kilometers over a single night, covering distances that they would normally fly only during migration.”
To figure out what role fireworks played, the researchers used air pollution levels reported by a network of local monitors to gauge where fireworks were most intense. Overall, air pollution where geese roosted more than tripled during the holiday. Three of the goose species showed a heightened preference for spots away from people during and after New Year’s.
The extra flying on that one night caused the geese to burn between 1% and 10% more energy than normal, the scientists calculated. The toll of the disruption lasted for days. During the week-and-a-half after, the birds spent between 2% and 10% more of their time engaged in movements consistent with foraging—lingering in fields during the daytime
“The birds are likely compensating for the extra energy they expended during the night of the fireworks,” said Nolet.
The findings raise questions about what might be done to help the birds. Nolet suggests a fireworks ban near national parks, bird sanctuaries and other key roosting areas.
But the groups’ own research points to the challenges of such an approach. In the first year of the COVID-19 pandemic, New Year’s fireworks were banned in all the western European countries where the geese were tracked. Still, at least two of the four goose species showed signs of turmoil.
That’s likely thanks to lockdown scofflaws. Despite the ban, people in the Netherlands were estimated to have shot off 30% of their usual fireworks. Neighboring countries might have followed suit, the scientists surmised. Apparently, it wasn’t just geese that were awake and on the move that night.
Kölzsch et. al. “Wild goose chase: Geese flee high and far, and with aftereffects from New Year’s fireworks.” Conservation Letters. Nov. 24, 2022.
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