Many of you will have noticed there are a lot of flying and crawling insects around at the moment. Those who work in the field of ants will know that there are tiny black and brown ones and big ones, Bull ants, with nippers on the ground while those that fly have taken to the air with the rains we've been having lately.
The ants we’re most used to seeing are female black garden ants or the brown coastal ants, marching around collecting food. But during Summer, winged males and new queens of the same species take to the air. The ants take to the skies so that queens can mate with males from different colonies, and set up new nests of their own. For a swarm of ants to occur, conditions must be just right – they’re usually triggered by hot and humid weather, which is why we start seeing them in late November and swarms of them over Summer.
There are also moths flapping around at dusk and all through the night, although we haven't seen any bogan moths for years now, along with the first cicadas emerging these past few weeks - in fact, at Avalon, Clareville, Narrabeen and Elanora Heights people have been seeing Greengrocer cicadas emerging and shedding their skins. The past few years we've had masses of Black Prince cicadas emerging and trilling for around six weeks making a deafening noise.
Insects (from Latin insectum -Etymology. From Middle French insecte, from Latin īnsectum, from īnsectus “cut into, cut up, with a notched or divided body”, from the notion that the insect's body is "cut into" three sections; head, thorax, abdomen) are pancrustacean hexapod invertebrates of the class Insecta.
Insects are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed legs (six legs!), compound eyes and one pair of antennae. Their blood is not totally contained in vessels; some circulates in an open cavity known as the 'haemocoel'. Insects are the most diverse group of animals; they include more than a million described species and represent more than half of all known living organisms. The total number of extant species is estimated at between six and ten million; potentially over 90% or 4/5ths of the animal life forms on Earth are insects.
This Issue a few of those we've spotted in our own yard and around the streets this past week.
Some ant species live in colonies that are supported by a single queen while others are supported by multiple queens. Although there are 1,300 ant species known in Australia, there are relatively few that we commonly see as pests as most are what is termed 'beneficial insects'.
Beneficial Insects
Beneficial is an adjective with a meaning of 'resulting in good; favourable or advantageous'.
Ants are known as beneficial insects because they keep the ecosystem clean of dead insect carcasses and aid in the destruction and decomposition of plant and animal matter. By carrying bits of plants and animal remains into their nests, the soil is fertilised and nutrients recycled through the world's ecosystems.
Other beneficial insects are bees, ladybugs, moths, lacewings, red and blue beetles, and a small native wasp, Microplitis. There are others - but in just these we have those that get rid of bugs that may destroy your plants, along with those that carry pollen to other plants to help them flower and grow into fruits and vegetables and nuts.
That's why you want to encourage insects to come into your garden by planting species that will attract them or making sure there's some good habitat for them - flowering plants, rotting logs, trees that have hollows, patches of grasses and rocks.
Ok - some of the insects we've spotted in the last week of November 2023.
Late November insects seen this past week
Bull ants are large, alert ants that can grow up to 40 mm They have characteristic large eyes and long, slender mandibles and a potent venom-loaded sting. They have superior vision, able to track and even follow intruders from a distance of 1 metre. Many species of bull ants have bright red or orange colours on the head or abdomen.
There are about 90 species of bull ants in Australia with diverse behaviours and life cycles. Nine bull ant species have been recorded in Sydney, but there may be more as yet undiscovered. Some of the smaller species are known as jumper ants after their habit of aggressively jumping toward intruders.
Bull ants live in urban areas, forests and woodland, and heath, including the coastal heath ecological communities we have here in Pittwater. Bull ants collect nectar and other plant juices, as well as animal prey, which are carried back to the nest.
Bull ant nests are usually underground and often have hidden or small entrances. The nests can extend several metres below the ground. They attack intruders of any size that come too close to their nest. Bull ants also have well-developed vision and will follow or even chase an intruder a good distance from the nest. Usually the sight of large aggressive ants streaming out of the nest is enough to prompt a hasty retreat. If not, the ants deliver painful stings by gripping the intruder with their mandibles (jaws), curling their abdomen to reveal the sting and injecting the victim with venom. Often multiple stings are delivered.
Several species have no colony workers. Instead, a raiding queen invades the nest of another species, kills the resident queen and takes over the colony. The queen may live for several years.
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Bull ant, Myrmecia sp, taken in bushland surrounding Swifts Creek, Victoria. Specimen is approximately 25mm in size. Photo: fir0002.
These ants can deliver painful stings and are aggressive. An ice pack or commercially available spray may be used to relieve the pain of the sting. If there is evidence of an allergic reaction, medical attention should be sought.
The Greengrocer Cicada, Cyclochila australasiae, is probably the most commonly encountered in the Sydney area. The two common names of Greengrocer and Yellow Monday refer to different colour forms of the same species. The origin of the names is unclear but they are known to have been in use as early as 1896. Other names for different colour forms include Chocolate Soldier (dark tan form) and Blue Moon (turquoise form).
Greengrocers are common on a range of trees, the adults spend much of the daytime sucking sap from branches.
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Greengrocer Cicada, Cyclochila australasiae, photographed Thursday November 23 2023. Photos: Selena Griffith
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Dusk is the usual time to hear the male Greengrocers calling for females, but they also sing in the morning on warm days. The harsh song may be continuous or delivered in short bursts, and can be extremely loud and penetrating.
Adult Greengrocer cicadas live for around six weeks. Females deposit eggs into dead or dying branches of a food plant. The eggs hatch after about four months into spidery-looking, long-legged nymphs that burrow into the soil. Here they suck sap out of plant roots and grow for up to seven years, emerging as adults between September and November on warm nights often following rain.
These little flying beetles make their appearance around now and this one flew into our kitchen this week - that's Eric's finger it's resting on so we could take some photos for you. It then flew off again!
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This is a Phyllophaga and part is a very large genus (more than 260 species here) of New World scarab beetles in the subfamily Melolonthinae. Common names for this genus and genera of the subfamily are May beetles, June bugs and June beetles as they appear in America during those months (they have 750 species counted so far) although here they appear during our warmer months of November, December and January.
They are quite hard shelled which is why you may hear them bouncing off your walls indoors, and fly very fast. They are medium to large oval or cylindrical beetles, body length 8-25mm. Body colouration commonly brown to reddish brown, and blackish.
Larvae of Phyllophaga feed on the roots of a large range of plants and grasses. Adult beetles feed on plant foliage, and can cause significant damage when mass emergences occur. Both forms can have severe impacts on a large number of cultivated crops including maize, sorghum, wheat, rye, beans, oat, potato, sugarcane, turnip and cranberry. They can also be a significant pest of pastures and turf. Most adults emerge late spring/ early summer. Adults are nocturnal, and attracted to light. Night feeding beetles are not easily disturbed, leading to easy collection from their host plants. Among the recognised pest species in Australia are: P. anxia, P. crinita, P. ephilida, P. elenans, P. fusca, P. implicita, P. menetriesii, and P. vicina.
We also spotted a Christmas Beetle on Saturday Morning, November 25, unfortunately someone had stepped on it and it was squashed. Christmas beetle is a name commonly applied to the Australian beetle genus Anoplognathus, which belongs to the subfamily Rutelinae. They are known as Christmas beetles because they are abundant in both urban and rural areas close to Christmas.
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There are about 36 species of Christmas Beetles (family Scarabaeidae) with all but one unique (endemic) to Australia and 21 species found in New South Wales. At least 10 species occur in the Sydney region – more if the Blue Mountains are included. Anoplognathus viriditarsus is the largest of the Sydney Christmas beetles.
Christmas Beetles come into Sydney from surrounding woodland where the adults feed on eucalyptus leaves and the larvae feed on grass roots. Adults can occur in large numbers, sometimes completely defoliating trees. The total number of Christmas Beetles reported in the Sydney area has declined over the last 30 years as the grassy woodland areas get used up for housing.
This moth is a Acosmeryx cinnamomea, a species of in the family sphinx moths. Sphingidae (Sphinx Moths) is a family of Lepidoptera (Moths And Butterflies). They eat the leaves of Cayratia clematidea (wild grape), Cissus antarctica (Kangaroo vine), Cissus oblonga, Vitis vinifera (wine grape/edible grape), Vitis vinifera rupestris (ornamental grape). They are Nocturnal - Active at night. Their colour ranges from brown to grey. Their size at rest - tip of thorax to tip of either forewing: 49mm.
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As you can see, this one has a bald spot. Moths and butterflies constantly accumulate damage on their wings and bodies over time, and they're especially prone to loosing the delicate scales that coat their exoskeleton (which is usually visible as a 'bald spot' on the top part of a moth's thorax when it's been bumping around a light for a few hours). You can even get a sense of a moth's age by seeing how worn and tattered its wings are; newly emerged individuals are usually pristine, while older ones have frayed wings and patches of missing scales.
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The species is found in North-Western WA, Northern NT, Far North Queensland and south along the coast through QLD, NSW to northern tip of VIC. The caterpillar grows to a length of about 8cms. The pupa has a length of about 4.5 cms.
Finally, how about one more of the moths you are likely to see at present? This one flew in and hovered around the computer and then dived down the back of the desk, where there are heaps of cobwebs, on Friday morning at dawn - obviously coming indoors for the day - and reminding me to clean behind my desk! - whoops....
This is a Tiger Moth.
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Unlike many other moths, Tiger Moths has bright orange bars and spots on its wings. They have striped abdomens which has given them their name. Most Tiger Moths fly at night but some are day-fliers. They do not fly very fast.
Most Caterpillars of the Arctiidae are covered in dense dark hairs, which gives them the name "Woolly Bears". The hairs can cause irritation in sensitive skin. The caterpillars are small to medium size. The caterpillars usually active during the daytime. If disturbed, they will roll into a tight spiral.
Tiger Moths live on the coastal areas of eastern Australia. You will find Tiger Moths on plants usually around flowers, around water such as puddles and in the air.
After dark Tiger Moths emit ultrasonic clicks which can be picked up by insectivorous bats. These clicks warn the bats that the moth is unpleasant to eat, and also jams the bats’ sonar system.
The Tiger Moth is a food source for small birds. Luckily for the Tiger Moth, most predators know its marked patches of orange and black mean that the moth is distasteful or poisonous.
They love to drink the nectar from wildflowers and prefer an established garden, where they can also eat lichen. Lichen occurs when fungi and algae grow together. In rainforests and alpine forests it forms a large carpet on the ground. Keep a look out for grey, green or yellow patches on your backyard rocks and trees.
Finally, a lot of our local insects are food for birds that live here. This week we also spotted the pair of Butcher Birds that live in our yard have had two babies this year and they are now able to fly around a bit, known as 'fledglings' at this stage, and be taught how to catch insects for their own dinner. Although, as you can see from the photos, one was trying out a larvae as well.
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calling to mum and dad; feed me! feed me!
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leaning off the top of the fence top get a larvae pod
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success!
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his/her brother or sister was a little further along the same fence top, also hunting for insects
Ok - we'll keep taking photos of insects we spot over Summer and will bring you more on our local insects soon.
Information from the Australian Museum and Backyard Buddies and the NSW Department of Primary Industries Photos: A J Guesdon