Are you fascinated by wildlife and curious to learn more about the St Mark’s fly (Bibio marci)? This species of fly is found throughout the UK, and has some unique characteristics that make it an interesting study for any nature enthusiast. In this article, we’ll be exploring the identification, habitat, and life cycle of St Mark’s flies, so if you’re keen on learning more about these insects, then read on!
Overview
The St Mark’s fly (Bibio marci) is a species of fly belonging to the family Bibionidae. It is found throughout Europe, including the UK, and parts of North Africa and Asia. This species is also known as the hawthorn fly.
The St Mark’s fly is classified as an insect in the order Diptera, which includes all true flies. Its rank within this order places it in the suborder Nematocera, and its family Bibionidae contains over 400 known species worldwide.
How To Identify a St. Mark’s Fly
St Mark’s flies have an average body length of 4-5mm and are usually black or dark brown in colour, with yellowish markings on their thorax. Its wings are transparent and have distinctive white spots near its tips.
The St Mark’s fly can easily be distinguished from other similar species by its size and colouration. For example, it is much smaller than the common housefly, which typically measures 8-10mm long. The yellowish markings on its thorax also make it unique compared to other flies, such as the hoverfly or blowfly, which lack these features.
Where and When To See Them
When looking for St Mark’s flies, they tend to inhabit areas where there are plenty of flowers, such as meadows, gardens and parks during summer months when temperatures are warmer.
They are most active during springtime when they emerge from their winter dormancy period and can be seen swarming around trees and shrubs looking for mates or food sources like nectar or pollen from flowers.
In terms of behaviour, St Mark’s flies move quickly between plants while searching for food sources, so they can often be difficult to spot unless you are paying close attention.
St. Mark’s Fly Habitat
The St Mark’s fly prefers damp, wooded areas such as forests and riverbanks, where it can find plenty of decaying vegetation to feed on. During summer months, they may migrate further north into Scotland or even Scandinavia in search of cooler temperatures and more food sources.
St Mark’s flies are often found near bodies of water like rivers or streams because they need moisture for survival. They also prefer shady spots with lots of leaf litter and rotting logs that provide them with shelter from predators and a source of food. In addition to these habitats, St Mark’s flies have been known to inhabit gardens, parks, fields, meadows and other open spaces where there is plenty of plant material available for them to feed on.
During winter months, when temperatures drop below freezing point, St Mark’s flies will seek out sheltered spots like hollow trees or caves in order to survive until spring arrives again. They are able to hibernate during this time by slowing down their metabolism until conditions become favourable once more for them to emerge from their hiding places and start searching for food again.
Life Cycle Of The St. Mark’s Fly
These insects have an average lifespan of about one month, but can live up to three months if conditions are favourable. During this time, they will go through four stages: egg, larva, pupa and adult.
The female St Mark’s fly lays her eggs on vegetation near water sources such as ponds or streams. After hatching, the larvae feed on decaying plant material and small aquatic organisms until they reach maturity.
Once mature, the larvae enter into a pupal stage, where they remain for several weeks before emerging as adults. Adult St Mark’s flies have short lifespans but can live up to two months, during which time they will mate and lay eggs again to start the cycle anew.
Predators Of The St. Mark’s Fly
Predators of this species include birds, spiders, frogs, lizards and other insects that prey upon them at various stages of their life cycle, from larval through adult stages. This helps keep populations in check while also providing food for these predators; it is, therefore, important to maintain healthy habitats for both predator and prey if we want to ensure stable populations of this insect species in our environment.
Ash is a contributing author who has been writing about wildlife for as long as he can remember. He has a vast knowledge of many different types of animals, from the tiniest shrews to the great whales that live in the deepest oceans.
Are they harmful to fruits?
They may occasionally cause some damage to fruits by feeding or laying eggs, but they are not considered a significant pest to fruit crops.
Are they a danger to our veggie places in the garden?
No, they are not considered a danger to vegetable gardens
There are a number of what we think are St Mark’s flies in or pond ( they don’t look happy) is this normal behaviour or should we fish them out?
Perhaps let nature take its course and leave them be.