>> What are these Britains doing? Rounding up swans on the river Thames, counting them, tagging and releasing. This strange census for waterfowl all in duty to their Queen Elizabeth. They call swan upping and it's an obscure annual tradition that dates back to the 12th century. That's because back then these birds were considered a delicacy, so the monarchs of the time claimed ownership on all the creatures and wanted to keep track of them and by law the Queen can still claim that right today.
Lucky for these guys they're not eaten anymore, instead the spectacle is carried out for fun but it also plays a role in their conservation. The number of swans in the Thames have actually gone down in recent years. From 120 in 2014 to only 72 last year, partly from predators and pollution.
>> We weigh them, we measure them and we check them for any injuries. Quite a common injury would be fishing tackle and we de-tackle quite a lot of young cygnus. I've been doing it for 24 years.>> The Crown says they've also seen an uptick in animal abuse.
These colorful bureaucrats now hoping to protect their feathered neighbors.