This year’s annual emergence of St Mark’s Flies (Bibio marci) has begun today. A lot were seen flying above the path between the Rock Garden and Woodland Garden at lunch-time – just in time for a wedding for which the seats were laid out in the nearby redwood grove! The emergence is MUCH later than in recent years: last year the first record was 16 May while in 2011 it was 3 May. St Mark’s flies get their name because they (are supposed to!) emerge around St Mark’s Day, which is April 25th — this year they are appearing about a month later than that day! They are easily recognisable by their long legs that dangle in flight. Adults only live for about a week, so it will all soon be over …..