The Hawthorn Fly – All You Need To Know
The Hawthorn fly (Bibio Marci) is one of the first flies of the season known as ‘Terrestrials’, these are flies which do not originate from the river, but do end up on it as food for Trout. The Hawthorn Fly is sometimes known around the country as The St. Mark’s Fly, because they emerge around St Mark’s Day (25th April) every year. This fly belongs to the Family Bibionidae and there are around 20 different species found throughout the UK.