Especially from mid-December, they have been very numerous over grass, in gardens, and around wetlands. On warm evenings they have been particularly noticeable, at all levels, often rising to twice treetop height or higher in their search for their small flying insect prey.

Many species are territorial, defending their territories from others of the same species, or from other larger insects generally.

Damselflies are numerous too; they are similar to dragonflies, but smaller and slimmer. They hold their wings lengthwise along their tails when resting, rather than out at right angles.

READ MORE: Why this 'alarming' creature is a handy primeval friend for Ballarat right now

Dragonflies and damselflies emerge as adults in spring. After a week or two the males select and defend a territory.

Today's photo, taken recently at Ballarat's North Gardens Wetlands, shows a male Australian emperor dragonfly - one of the larger, yellower species - clasping onto the head of a female laying her eggs under water. Pairs of dragonflies and damselflies are often seen flying in tandem before this occurs.

Adults generally live for one or two months, having previously spent months or almost a year as nymphs in wetlands.

The study of local dragonflies and damselflies goes back only a relatively short time. A 2013 Lake Wendouree list by local enthusiast David Leviston contained 18 species, and a couple more have probably been added since. There are more than 30 species known in the Ballarat region.

There are now books available covering all Victorian species. Many are confusingly similar, and their wariness and their rapid movements make them difficult to identify easily, despite the good books.

Keen observers and photographers have learnt to seek them in cooler morning temperatures, when they can often be found resting. They fly less readily at that time. These predatory insects would account for a huge number of mosquitoes and similar insects every day of summer.

It was a surprise several years ago when an eastern Victorian migratory bird called a cicadabird was discovered in the Wombat Forest at Spargo Creek.

The species has returned each year since, and has recently been sighted again for another summer.

Males have a strange cicada-like churring call, hence the bird's name. They are dark grey, about the size of a blackbird. Females are very different - grey-brown above and finely barred black on white below.

Both sexes are treetop birds, rather flighty, and seldom easy to observe, with females rarely calling. They would hardly be noticed if not for the male's unusual call.

Are you able to tell me what is on the back of this cockroach?

M.M., Brown Hill.

This is a female cockroach with her egg-capsule protruding from her body. This is the normal way for many female cockroaches to carry their eggs.

The egg-capsule is either eventually deposited in a safe sheltered spot, or is retained by the female until hatching occurs. According to species, it contains from about a dozen eggs, or up to 30 or more. Its hardened surface protects the eggs from predators, and it also protects them from becoming too dry or too wet.

Although there are introduced cockroaches that are often found in kitchens and bathrooms, there are also many native species that never come inside. The one pictured appears to be outside in a garden, so is probably a native. It has a wider body than the introduced pest species.