20,000 bees

This just out of Jolly Old Blighty; A swarm of bees forced a jet to land at Bournemouth, England after it was sucked into one of the engines about an hour into the jet's flight to Faro, Portugal. There was a surge in engine power and then the pilot turned back and landed. Mechanics got to work, scraping out the bee juice and after eleven hours they gave up and brought in a back-up jet.
Some witnesses "claimed there were around 20,000 bees."

My question is this; When you count bees do you count the legs then divide by six, or count the antenna and divide by two?

My second question is this; I wonder if this helps explain what is happening to the world-wide bee population (which is dropping dramatically)?

Anyway... Humouroceros