Sunday, December 14, 2014

An Epic Battle On The Oak Branches

  Scale insects swarmed the oak's branches until it looked as if they would overpower the oaks.  Then, the scale insects' enemies showed up in droves to conquer the scales.   The scale insects' strategy was to multiply in overwhelming numbers.  Their enemies' strategy was to one by one infect, eat, or destroy as many scale as possible. Who won the battle? 
Twice-stabbed Lady Beetle lays eggs on scale insects
Here in this photo, the scale insects cover an oak branch and a Twice-stabbed Lady Beetle is laying eggs on the scale insects.  Its larvae will feed on the scale insects.

   I posted about a scale insect infestation and the scale insect predators previously.  Who won this battle for the oak branches?  Did the scale insects win, or their enemies: the entomopathogenic fungi,  tiny parasitic wasps, and other predatory insects (like the lady beetles) that prey on the scales?  Here is an update on that epic battle with photos showing the carnage.
scale insect enemies


  Fungal entomopathogen spores landed on the scale insects' cuticles and infected many of the scales, eventually killing and digesting them. 

scale insect with fruiting bodies of entomopathogenic fungus


 These two photos show fruiting-bodies growing post-mortem out of the parasitized scale insects.
fungus infected scale insects

Other enemies of the scale insects were several species of tiny parasitic wasps.  These next few photos show some of these parasitoids laying eggs on the scale insects.

tiny parasitoid wasp laying eggs on scale insects


The tiny wasps had a big job scurrying around over the hordes of stationary scale insects and selecting suitable ones where they would lay their eggs.

parasitic wasps laying eggs on scale insects


The wasps' larvae developed inside the scale insects as they fed on the scales or the scales' eggs.

parasitic wasp laying eggs on scale insects


Here is a photo of a scale insect shell with plenty of exit holes from the mature wasps.

scale insect full of holes from exiting parasitic wasps


In this epic battle for the oak branches in a forest near me, hordes of scale insects were attacked by wasps, the entomopathogenic fungi, and the larvae of  beetles like the Twice-stabbed Lady Beetles...
scale insects killed by wasps and fungi

.... as you can see, the scale insects' enemies won the battle.