I’ve been seeing so many ladybirds (Coccinellidae) in my garden in the past few weeks. Every one is a different shade of orange and has a different number, pattern and shape of black spots.
The street tree on my front verge (planted and maintained by the local council) was recently pruned because it grows under power lines. The council workers shred and take away lots of what’s pruned, but there’s always many smaller cuttings that litter my verge and garden and I put them in my compost bin. When I was doing this I noticed numerous ladybirds on the cuttings and I wondered if they like this particular tree.
I found another ladybird sitting on my fence on top of a cocoon. I know that cocoons usually come between the juvenile and adult stage in an insect’s development, but for some reason I thought she was laying eggs that were then wrapped in the cocoon. I realised the error in my thinking after investigating ladybird reproduction. They lay yellow eggs in sheltered places , often near aphids to provide food for the hatchlings, and like many insects the larvae look completely different to the adults . The fence is not sheltered and there are certainly no aphids on it. Then I remembered a small wasp was hovering near the ladybird when I first saw it. The wasp was probably hoping to join in the meal.
There are over 300 species of ladybird in Australia and not all of them are carnivorous. In the UK they hibernate in winter , but in Australia
ladybirds can be found all year round, but are particularly numerous in early spring, when the warming weather makes them more active. 
There are four species that are widespread across Australia, but only three are found in WA. The transverse ladybird (Coccinella transversalis), common spotted ladybird (Harmonia conformis), and variable ladybird (Coelophora inaequalis). I’ve seen the first two in my garden.
Ladybirds need nectar and pollen sources to lay their eggs  and the street tree is flowering, so the warm weather and abundant nectar and pollen is the reason for the profusion of ladybirds.
- Mabbott, Peter (2005) Reproduction and Life History of Ladybirds.
- Thomas, Abbie (2002) Killer Ladybirds in The Scribbly Gum. ABC Science.
- Chew, Peter (2005) Ladybird beetles (Family Coccinellidae) in Brisbane, Queensland.
- CSIRO (2007) Look inside the secret world of the ladybird beetle (vodcast).
- Ślipiński, Adam (2007) Australian Ladybird Beetles: their biology and classification. Canberra: Dept. of the Environment and Water Resources.