Black flies (Simuliidae) (Buffalo gnats)

Question 1

Where are Black flies distributed?

Why are they found near permanent or semi-permanent running water?

Answer 1

• world-wide distribution
• running water required for larval development

Question 2

What are some morphologic features of Black flies?

Answer 2

• 1.5-5mm long
• humped back
• wings held over back like a pair of closed scissors

Question 3

How are the eggs laid?

Where do the larva develop?

Answer 3

• eggs are laid in sticky masses of several hundred on partially submerged stones or vegetation in flowing water
• larva develop submerged and attached to objects

Question 4

What is the pathologic significance of Black flies?

Answer 4

• painful bites and high population density ==> disturbs grazing
• mass attacks can cause death
• transmit:
  
  • parasites
  • viruses - vesicular stomatitis virus, E equine encephalitis

Question 5

What are some control methods for Black flies?

Answer 5

• insecticides applied to breeding sites to kill larvae
  
  • repeated application to selected water sourses at intervals throughout the year, which is then carried downstream and kills larvae over long stretches of water
• repellents to horses
• dusting of poultry