Plague Soldier Beetles

by Jo
Publish date
15 January 2012
Comments (153)

Your Question: What are these swarming beetles in my garden?

The Discovery Centre has received many enquiries over the last few weeks about swarms of beetles in suburban gardens in and around Melbourne; they are Plague Soldier Beetles, Chauliognathus lugubris.

Plague Soldier Beetles Plague Soldier Beetles
Image: Peter Saunders
Source: Peter Saunders


This flattened, elongated, soft-bodied beetle has a thin yellow-orange stripe across the back of the pronotum. It has metallic olive green elytra (hardened forewings), covering most of a yellow-orange abdomen. The legs, head, antennae and rest of the pronotum are black and the beetle is usually about 15mm in length. This native species has earned its common name of the Plague Soldier Beetle not as a result of bringing or spreading any dangerous plagues, rather due to its habit of forming huge mating swarms.


Plague Soldier Beetles Plague Soldier Beetles
Image: Peter Saunders
Source: Peter Saunders


The larvae of this species live in the soil and feed on soft bodied invertebrates, while the adults feed on pollen and nectar. The species is found across large parts of the country including urban areas and adults can be seen from spring through to autumn. During their mating periods they can appear in such large numbers that it is not uncommon for them to weigh down the limbs of weaker plants.

Their bright colour warns off predators as they are capable of releasing distasteful chemicals and would not make a good meal. For homeowners who may be hosting huge numbers of this colourful species, don't be too concerned, following the mating swarm the beetles tend to disperse.


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Comments (152)

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Jeannine 15 January, 2012 17:33
Thanks answered our query. We have a large collection of these at a damn near Glenlyon in Victoria and no one seemed to have seen them before or find out what they were.
wombat lyons 23 December, 2012 22:32
We have lots in Yarragon at the moment- only see them on the hot sunny days
Ileana 17 January, 2012 10:42
Really appreciated posting this, was a bit concerned, we had them in Lugarno, NSW. We blew them away with air and they kept coming back.
Anne 27 November, 2012 23:58
I am desperate. Whilst I appreciate the beetles are doing no harm, I have a big Christmas function in my back garden (58 people) in 11 days. From the comments, it seems they may not be gone - what can I do?
Jan 20 January, 2012 15:43
We have had thousdands of these in our garden for the last 2 weeks. They have 'moved' from the front garden to the back garden this week in their thousands
John 21 January, 2012 15:49
Covered front wall in clumps at Macedon Victoria, from a distance looked like some one had splatered it with mud.On inspection seemed like they were in a breeding frenzy.Have now dispersed into smaller groups around property.Glad i looked up this site before going into destruct mode.
Pete 22 January, 2012 10:41
Have had thousands on block the past weeks here at Lysterfield. Cold weather caused them to mass overnight on verandah. Today with heat they are up in the gum blossoms going gaga. Glad to know no problem although web suggests not too much known about them.
Ian Jones 3 February, 2012 16:12
Thank You. We have them in Oak Park, Victoria and they appear to be swarming around a couple of gum trees.
sharleen 3 February, 2012 17:51
i have thousands and thousands of these in my back yard how do you get rid off them i am not happy to just leave them after 2 weeks since my kids cannot play out the back they are all over there swingsets and cubby
Anita 8 February, 2012 11:08
Thanks for the info. Have them in swarms in my back yard in Mount Martha. Glad to know they are not doing to much harm.
Ian 8 February, 2012 17:35
Thanks to the Knox Council and info above. We live in Boronia Melbourne with the National Park adjacent to us and behind us. Virtually overnight these beetles have swarmed and there would be thousands upon thousands of them. Good to know they are not harmful and in fact they are actually a good thing.Hopefully they will move on soon
Jo 14 February, 2012 19:49
So glad I came across this. I have been trying to track down what these are for weeks. They have descended on us in Mount Waverley in their thousands. Ours too moved from the front yard where most mornings they could be found all over my car and have taken over the backyard and a large gum which in 14 years we have never seen flower before. Was beginning to think this was some kind of biblical plague!
Melissa 29 February, 2012 14:20
Another glad recipient of this information - in Bayswater North and the backyard is swarming with this little creepy crawlies!! Glad to hear they will move on after mating - lets hope that process is a quick one!
Grant 29 February, 2012 14:39
Same story where we live in Mandurang on the edge of Bendigo. Thousands of the bugs crawling around all over the ground, walls, rubbish bins, etc. mating. Hope they disperse soon!
Rosemary Pratt 1 March, 2012 00:41
Are the Plague Soldier Beetles one of the Longicorn species?
Discovery Centre 1 March, 2012 08:46
Hi Rosemary, the Plague Soldier Beetle is not one of the longicorn species; the Plague Soldier Beetle comes from the family Cantharidae, while the longicorn beetles come from the family Cerambycidae.
Jane 2 March, 2012 19:35
Thanks I've been waiting for rentokll to get back to me all week (only for identification purposes and safety of our dog). We first saw them at Somers in January and now we have them in Balwyn.
tony 6 March, 2012 16:02
I first noticed these beetles on my potatoe patch around December now I discovered their huge offsprings in clumps, around the garden beds .What sort of damage can they cause around the garden and what is their favourite meal
Discovery Centre 8 March, 2012 14:24
Hi Tony, when you get huge swarms of these beetles it is generally a mating swarm, so they don't tend to be doing much eating. They shouldn't cause much damage although if there are huge numbers and they rest on weak or delicate plants they may weigh them down and break them. The adults eat predominatly nectar, pollen and soft bodied invertebrates.  
tony 8 March, 2012 17:05
Ok thanks Discovery,so I won't have to worry about them as I don't like to use any kind of spray unless I have to.Tony
Nathan & Kylie 25 March, 2012 14:30
This is our 2nd plague of soldier beetles in 4 months, our 1st was 24th of november and our house is under attack again, they have come in under the tin roof and into our house via down lights and fans. i would hate to see the inside of our roof....
Dean 1 November, 2012 11:12
Hello Discovery, Today, we have encountered a mating swarm over the front of our house in Malvern and all over and through the engine of our car. My question is: How long will this swarm or infestation last? One or two days or longer? Thanks, Dean
Discovery Centre 5 November, 2012 13:46
Hi Dean, the length of time that these beetles will spend in an area can vary; it could just be a day or two or it could be up to a week or so. The adult stage of this beetle species is very short, so they quickly need to get together, mate and for the female to lay her eggs before they die. So hopefully they will be off your car and house shortly.
Kaylene 4 November, 2012 07:00
Hi we have these beetles every where in our back yard as well we are in newcastle they are loving our tree which is flowering
Carl 4 November, 2012 17:35
Hi we have a swarm at Taggerty just arrived today in a mating frenzy, they seem to prefer white or light coloured flowers to congregate in.
Karena 5 November, 2012 11:47
We have them in our garden in St Andrews. They are all over roses and any other blossoms they can but don't seem to be doing any damage.
Robyn 8 November, 2012 09:38
Great information. We live in Yea and have had literally thousands of these beetles in the trees, particularly on every blossom. I've never seen them before and I was worried that they might be a 'pest' beetle ... glad to hear they are somewhat beneficial. And they do look like they are really enjoying themselves !!! Lastly, does anyone know how long they'll be here (it's been nearly 2 weeks now) ? But I noticed that on my Malus blossum trees (which they seem to particularly love), the bees don't seem to mind them because they are all in there together.
Hannah 8 November, 2012 12:24
You say they like soft bodied invertebrates, but does include aphids? I noticed them on our White cedar and Robinia trees last year but now they are everywhere,and all over our vegetable garden, hoping they might be beneficial?
Discovery Centre 10 November, 2012 13:38
Hi Hannah, yes these beetles are likely to take aphids. The downside to them in your garden can be that if their numbers are sufficiently large they can weigh down some young or weaker plants. 
Kirstin 9 November, 2012 10:45
We have a massive swarm of them in our front yard on a lemon-scented gum tree in Greensborough - happy to know they are not dangerous and will be eating the aphids off my roses.
jeanette 9 November, 2012 11:14
we have had about 4 really bad infestations over past few years. in Katoomba nsw. especially when summer begins. now they are back. unfortunately i cannot stand to look at their clumps as they are in backyard within my sight whenever i sit in kitchen!they actually turn my stomach!! i'm afraid we have sprayed them previously before we knew what they were. we used mortein outdoor spray but upset my asthma! Karen 7th nov asked what happens to their eggs? do they lay them back into our garden soil or fly elsewhere? i will look at site again for reply. thanks
Helen 10 November, 2012 14:15
Thanks for this information and everyone's questions and experiences. I was shocked to discover my back deck, furniture and a number of shrubs teeming with these beetles. You have eased my mind.
Mary 11 November, 2012 17:28
On 14th November 2011 these beetles were identified for us after great concern for the plague we were experiencing. Exactly a year later, they are back in greater proportions. The seem to have taken over Healesville. Thanks to last year's identification, we know not to worry. They are pesty though.
sophia 13 November, 2012 15:10
Do these insects bite or sting humans? Have a large swarm at our house in Wodonga Victoria.
Discovery Centre 14 November, 2012 11:13
Hi Sophia, these beetles do not bite or sting people; they do have chemicals they can release as a deterrant to predators.
David Newport 13 November, 2012 23:12
They're beautiful and a real Australian icon - all dressed in green and gold! There are many of them in Wangaratta at the moment.
Dianne 17 November, 2012 14:14
So glad to hear the above news. Have noticed these beetles over the last week or so but it wasn't till I went out this morning to fertilise my pittosporum hedge that I saw how densely they have populated said hedge and elsewhere in the front garden. Husband googled and I now feel at ease, though I could not see any damage. Glad to be a part of the ecosystem.
Discovery Centre 17 November, 2012 15:18
Hi Karen, we suspect the adults usually disperse before laying eggs or people would be getting swarms in the same place every year. Some people do report getting these beetles in consecutive years but we don't know whether that is because eggs have been laid on the property or whether the beetles are attracted by a particular flowering tree.


Helen 18 November, 2012 14:20
Just found hundreds on a tree in our back paddock (have 3.5 acres in Lara, Vic). Glad they are not a pest: husband was about to spray them. Thanks so much for info.
Aileen 25 November, 2012 21:34
Are these the beetles which have washed up on the beaches this weekend?
Greg 27 December, 2012 10:05
Probably. I've seen them washed up on Edithvale beach in the last few weeks.
Jen 25 November, 2012 22:22
I've seen them swarming in Campbellfield and Richmond. Do we have any idea why they have taken up residency in Vic?
Luke 27 November, 2012 14:55
I was watering the garden the other day and found these bugs on the back lawn. It was like a carpet of yellow and metalic green! Did not know what they were and was about to run the mower over them when I saw what they were doing... They were having a massive orgy party! It was like a beetle Woodstock in the middle of West Ryde NSW!
Gina 27 November, 2012 23:12
Thank you for the information, I am on the surfcoast and have seen these before but not the mass found on my watertank this afternoon, mating season indeed :)
Margaret Lee 28 November, 2012 19:37
I have spent days trying to identify these bugs. They have been swarming from Callistemon to callistemon as they come into flower and mating in major numbers. Good to heare that they like aphids!! I have too many of those as well. The Gurdies.
Fran 29 November, 2012 17:08
I have just returned from a holiday and was horrified to walk into my top floor Apartment (on the beach-front, Melbourne), to find millions of bugs like a dark carpet all over my floor to ceiling windows! There is no garden like all other comments,it was like coming home to a "horror movie". They had also gotten inside and nested under the blinds along the window frame, yuk! We spent the day spraying inside and out so that we could see out the windows! I have noticed these bugs a few times each year, but NEVER like they are now, what has happened to our eco system that they are in plague proportion as their name implies.
lisa 29 November, 2012 18:56
We last night and today must have millions in our front yard and on the house of the soldier beetles in a bayside suburb of melb they have litterly covered trees in their millions.......there back
Billy Embaz 1 December, 2012 10:12
Hi there Great info Got back from work to sunshine west Vic only to find these ozzy gernzy flying bugs every were, the tree on the nature strip was covered, the lawn, couple of shrubs as well with these crawling horny ozzy battlers. Luckily though quickly searched the bugs characteristics reason being I was ready to arm up and exterminate. Knowing now these guys are out partying before they drop, mate let them go for it -great way out - goes to show even our bugs have mutated as time evolved to the Aussie way...CoooooEeee
Chris 1 December, 2012 11:29
Thanks for the information A swarm of beetles decended on our yard in western sydney.
Denise 1 December, 2012 22:57
We live in Somerville and have these beetles by the thousands in our front yard on 3 lemon scented gum trees. I was getting quite concerned thought they might be a problem. Even tried to hose them off the trees to no avail they fell off trees then crawled back up and continued mating! - Hope they go soon - the kids hate them so do I! Does anyone know what country they come from?
Daniel 4 December, 2012 08:34
Denise, it says in the text that they are native.
Maria Sanko 2 December, 2012 21:26
This is the first time in my life that I have seen this creatures when it's so hot. And when it's cool they go away. I would like to get rid of them, as I go out and water the garden I get surrounded by them, about 6.30pm.
nicole 2 December, 2012 21:36
hi , i am in Melton , Vic and i have millions of them in the backyard freaked the crap outta me but good to know i can let the kids out the back
Jeanne 3 December, 2012 18:51
Hi Just saw thousands of them in the paddock in Lysterfield.Are they harmful go horses at all?
Discovery Centre 5 December, 2012 15:43

Hi Jeanne, we have checked with the Entomologist, and he has found no record of the Plague Soldier Beetle being harmful to horses.

Laura 4 December, 2012 12:46
So glad I found this site too cause they are clumps and hundreds of them on only one side of the house I have never seen these in Melbourne in such large numbers in all my life. We live in Narre Warren South, and I have also noticed the cockatoos and crows around more and in large numbers, no doubt they're eating these beetles. Glad they aren't harmful but they do look freaky in there large clumps...dirty little
Michelle 4 December, 2012 22:00
Hi all, we live on the South Coast of NSW and have these covering the external walls of our top floor apartment, despite the reassuring posts these bugs will keep me from using our verandas till they have moved on!
Jayne 4 December, 2012 22:19
We live in Dover Heights in a two storey house. Thousands of these beetles are all over our eaves & clumped on the windows - just gross!
nathan 5 December, 2012 17:06
hey i live in montrose vic, theese beetles are everywhere in our front yard, millions of them from the front kerb all the way to our front door they're even breeding under the bonet of my car. they have been here for about 2 weeks now and seem to tripple in number every day. our whole front door and walls around it were pitch black with them and they leave yellow stains everywhere they go. i regret to say that i killed a few of them, but felt bad so i stoped shortly after i started but now things are out of hand and i dont know what to do and im getting tired of it verry quickly. is there a way to get rid of them fast without killing them?
Tim Buckley 5 December, 2012 17:48
Hi Discovery, Thanks for all the info, thanks also to those commenting. I'm a professional gardener/landscaper primararily in the bayside area of Victoria. Yes, they are everywhere, particularly on trees (those on the ground seem to have fallen from the trees). They crawl all over us when working with no harm. They certainly don't bother us or from a distance, the plants on which they are on. We are also experiencing repetitive doses of these beetles each year. My question from a botanical view, is, what small invertabrates are they consuming as larvae in the ground? and could this affect the micro activity that the plants (trees) may need to be at their best? There is no mention of control. Is it best to address the understoreys whilst in larvae form? much like the scarab(lawn beetle)? Thanks in advance
Discovery Centre 12 December, 2012 14:54
Hi Tim, I don't know that anyone has studied what species of invertebrate the larvae of this species feed on; as such we wouldn't be able to say whether the larval populations have any affect, (either positive or negative) on trees. 
Emily 6 December, 2012 07:39
I've been searching the web for an answer to our swarm of these bugs, happy to have an answer. They might not be harmful but is there any way of moving them on? I find their big dark climbs all over lawn, trees and walls very creepy.
Karen.D 6 December, 2012 09:30
We have had an enormous swarm (10s of thousands) of these all over our back yard for a week now. How long do they usually habg around? They seem to like a flowering tree in our yard but the neighbour has the exact same variety of tree & they're not going near that one. Very strange.
Discovery Centre 6 December, 2012 10:57

Hi to all the people currently hosting populations of Plague Soldier Beetles. We understand some of you find their presence somewhat intimidating or annoying but try not to be too concerned. The beetles are native and don't bite. People want to know how long they'll be around and how to prevent them coming back. It seems to vary considerably with some people reporting them leaving in a couple of days and some reporting them staying for more than a week.

The Museum is not aware of any treatments to prevent them coming back. These beetles can be a positive in that they will be consuming things like aphids. People can try squirting them with the hose to move them on but as they are very focused on getting together and mating the easiest thing may be to let them get that done and then they'll move on.  


Toni-Maree 6 December, 2012 13:23
I have them too! They are revolting. I'm afraid that I've spent the morning stepping on thousands of them that had decided to have their orgy on my back lawn.I just had to try and find out what they were and feel a little more relaxed now that I know.
Chris 6 December, 2012 13:48
I have had these in my garden since the start of spring and they have only multiplied, I live in hampton Vic, They seem to like raspberries unripe and ripe other than that they don't seem to done any other damage! But its time they must go after reading 90% of this thread. Good or bad I don't want them here!
Arty 6 December, 2012 17:51
Came home from work today to find a whole lot of these guys making whoopie on the plants under our lemon scented gum. I have lived in Marshall, Vic for about 10 years and this is the first time I have seen them here. Thanks for the info you have provided - as long as they leave when they have finished their business I don't mind them.
Angela 6 December, 2012 21:16
Thank you so much for putting my mind at ease, I have millions of these things around my home in Montrose. This afternoon I was about to pay a pest company $300 to spray my entire property, surely pest control companies know that they're harmless and will go of their own accord, they should let people know, luckily I found this site before spending money i haven't got. Now, could you just let me know how long my guests will be staying?
Vicki 7 December, 2012 07:56
We are in Berwick and some areas of the ground in our paddocks are moving with the density of the bugs on the ground. They are also on nearly every surface you can imagine - underneath leaves, all over branches, the edge of the verandah glass. My real concern is they are in the water troughs forming a black mass meaning the horses can't drink without us emptying every day.
Helen 7 December, 2012 08:10
I report thousands of beetles swarming in what appears to be isolated to one garden at Tootgarook on the Peninsula. Relieved to have them identified - thanks. They appear to have become active after digging in the garden, as that spot erupted with thousands, then they spread everywhere particularly clustering and massing over a small green children's plastic slide. The must have liked the color. This is the fourth day and the beetles are showing little sign of moving on as yet!
rosslyn 7 December, 2012 13:47
Have thousands of these beetles in my back yard, started by clumping on the lawn then went up into the trees now today they are flying everywhere. My only concern is for the past week we have had a lot of bees mostly on the buddlias, today with the beetles swarming there are no bees at all.
karen 8 December, 2012 08:37
I live in Bonbeach by the river and these pretty little beetles have been swarming my place in the tens of thousands off & on for about 2 months now. They leave for a week & just as I plan a sitdown catered xmas function for 20 people on my deck ......back they come. Agree they dont sting, but you just cant sit outside amongst them and my guests end up leaving because they are so annoying ! I see comments of them hanging around for a week or two. Ive had two months of it now ..... I hope I get to enjoy my summer on my new decking very soon :(
colin 8 December, 2012 20:33
Thanks for info. Have been bad in Altona for at least 3 weeks being particularly bad on hot days. Can't wait till they loose their mating urge.
Mick 11 December, 2012 11:39
Looked out side today a saw million of these buds about 30 to 40 meters in the sky. Looked like an invasion of bugs...very scary!
Jacqueline 12 December, 2012 08:21
Thanks so much for this information! None of my gardening guru friends had the slightest idea about this beetle or whether it was a pest or beneficial for gardens.
Paige 16 December, 2012 14:47
Leave our friends alone please. "Soldier beetles are highly desired by gardeners as biological control agents of a number of pest insects. The larvae tend to be dark brown or gray, slender and wormlike with a rippled appearance due to pronounced segmentation. They consume grasshopper eggs, aphids, caterpillars and other soft bodied insects, most of which are pests. The adults are especially important predators of aphids. They supplement their diet with nectar and pollen and can be minor pollinators. Soldier beetle populations can be increased by planting good nectar- or pollen-producing plants such as Asclepias or Solidago."
Helen 17 December, 2012 12:58
They may be desirable by gardeners but the tens of thousands I have had in my front yard for the last month are completely freaking me out they leave some sort of secretion behind that is ruining my painwork, I just need some sort of solution to keep them off my house!
Melissa 16 December, 2012 23:06
Thank you for the information! I can now tell my parents that they don't have to worry about our plants. It's really scary seeing so many of them clustered together!!
Sonja Boyce 17 December, 2012 15:29
Hi, I'm not too keen on the fact that they leave yellow stains on white washing. Cannot remove the stains, do you have any ideas? I'm glad they're not dangerous though.
Roma 20 December, 2012 14:36
I live in Torquay, and have had millions of them swarming in one corner of my garden for 2 weeks. They are flying around a giant lilli pilli tree that is flowering, and swarming on every plant and blade of gtrass under the tree. I tried hosing them, and sweeping them off the path, but they very quickly come back. I have asked people who live nearby, and they only have a few flying around. I usually see a lot of aphids on my roses at this time, but have none this year. I have also seen them washed up on the shore line at the beach.
Roma 27 December, 2013 13:50
They are back again this year. Again they are flying around my neighbour's giant lili pilli tree. When I shake a branch, they drop to the ground. They have not formed a swarm this year.(yet)
roma 5 November, 2014 10:33
They are back again! Earlier than the past 2 years. This year they have chosen a cream calistamon next to the lily pilli tree. The ones that drop off the tree are particularly attracted to my parsley growing nearby.
roma 28 December, 2014 14:57
It is late December, and there is a second wave of the beetles in my garden. There are not as many this time, and they are not swarming. They are in the same corner of the garden.
Vicki 20 December, 2012 16:34
I have them on my Sunbury property, scaring the life of me this morning when I went outside and saw the new lawn "moving" with hundreds of thousands of these things. Large clumps have formed on the verandah posts, and the chickens wont go near them!
Melanie 21 December, 2012 08:53
They have just arrived in our back garden in Mooroolbark, hanging off the seed pods on our large acacia shrub and all over the place in the vicinity. I was a bit spooked at this plague when it is supposed to be the end of the world today, but I am glad to learn that I don't need to worry!
Ray 21 December, 2012 19:53
I am in Glenhaven Sydney hills and i had millions apon millions swarming my flowering weeping lilly pillys. Thay are now clumped all over my herbs and all the rest of my garden nearest my lilly pillys. There are so many on the branches of the lilly pillys they are weighted down and look very heavy.My 13 year old daughter is now scared to go outside and i will be glad to see the back of them. I dont like the idea of chemical control ( i would probably need a tanker full) so i think i will just wait them out.
David Gillam 22 December, 2012 11:14
We should think of this as a gentle reminder that we share the world with others. I am quite surprised how people can be freaked out by nature. Perhaps it goes to show how some of us believe that nature should conform to us rather than the other way around. At the end of the day a minor inconvenience or a little yellow discolouration is not such a big deal, it it? Well, at least it shouldn't be. My 4 y/o daughter has been learning all about them and is not at all freaked out. Far as I can see, unless one of them accidentally flies in your mouth (not very tasty) then it's no big deal. The manicured lawns and fresh paint are after all , less important.
jay rao 23 December, 2012 18:31
plague of them in kew as well, and I initially thought they were flying baby cockroaches. Now I know what they are I am not worried that much. If they are inside the house wort vaccuming though. good luck and hope they will dissappear soon.
Tony Middleditch 23 December, 2012 18:54
Was travelling in the high country above Dargo a few weeks ago and found huge clumps of these beetles weighing down the trees up at the Pinnacles. Now, a few weeks later we have heaps of them at home in Lyndhurst We've never had these before, usually we have lots of Harlequin bugs this time of year I've noticed the Harlequins are almost non-existent I wonder if the Soldier Beetles do something to keep the Harlequins away?
Discovery Centre 26 December, 2012 12:06
Hi Tony, according to one publication from the 1980's swarms of Harlequin Bugs often move to cultivated plants from native trees, shrubs, and weeds along roadsides when these dry out in the summertime. There may be an element of competition between the 2 species but Harlequin Bugs and Plague Soldier Beetles have different food sources. It may also be that the Harlequin Bugs haven't yet started to move into people's gardens, (and hence become noticed) if sufficient moisture and nutrients still remain in these other plants. 
Bridget Kirby 23 December, 2012 21:19
As much as I'm pleased to read that they won't harm or devour our beautiful trees and veggie patch in our backyard, it would be nice for them to now move on. I feel 6 weeks of stained washing and and being swammed on ourselves when watering is long enough. My concern is that their numbers only keep increasing with no sign of them moving on. I fear it is due to the big flowering tree in our backyard that they have taken over. You mentioned in another post that they have a short life span. How long exactly is it? This will give me an indication of whether we just have a super large number of them or if we are getting new ones joining in all the time. Thanks
Discovery Centre 26 December, 2012 12:20
Hi Bridget, the adult Plague Soldier Beetles probably live for a couple of months only.
Wendy 23 December, 2012 22:10
Many thanks for the interesting read regarding these friendly and harmless beetles. I live in Mentone, Vic and they have been in my back yard for two weeks. I am looking forward to them finishing their business so we can once again enjoy our back yard. Nature is a wonderful thing but wish they would get on and do their job a bit quicker and move on !
David Norman 24 December, 2012 17:51
llive in bonbeach near the beach and they have nested in the trees in the unit block in their thousands just clumps of beetles seem to become more active in hot weather glad they are harmless otherwise it could be a horror story
Edward 25 December, 2012 16:11
thousands in my backyards and very annoying. I know they are harmless and hope they move on ASAP. If we don't do anythings now they may cause big problems in future. Thousands in this year , five thousands in 2 years and millions in five years and one day they may be out of control and is too late for us to control them.
Cheryl 27 December, 2012 15:18
Today found these flying and swarming in what seems like thousands at our property in Swan Bay NSW never seen this before, my husband thought they were bees until we went and had a closer look, found this great website, the name "plague" seems very appropriate, from all the posts it seems this Plague Soldier Beetle is spreading its wings and increasing its footprint around our turf, so much breeding has got to increase the numbers of this beetle and maybe could displace other pollen and nectar diners.
Richard 27 December, 2012 17:56
Have a major infestation in North Avalon NSW on a flowering gum. They were swarming (flying) the other morning - I thought they were bees - and did not venture close. The poor tree is suffering under the weight. Thanks for the info.
Diane 28 December, 2012 17:02
Just been to Kingston Council to find out information and they gave me this fantastic website. Wonder why the nasty looking Plague Soldier Beetles be infumigated? They are on our front door porch, in and out of letterbox and fence! Hundreds of them! Yuk!
Mal 31 December, 2012 11:23
These beetles look very similar to the masses which have colonised one of our large trees at Valentine, Lake Macquarie. Good to know that they are harmless and even better to know that soon they will move along!
Dan 4 January, 2013 16:00
We have just arrived home to hundreds of these beetles at our house, glad I found this website because I was getting worried. How long before they move on? We are in Melbourne, Vic
Maddie 4 January, 2013 08:32
They may be harmless, but when we can't get out our front door because as soon as we open it hundreds fall inside, they're annoying! They're coming into the house through every window at the front, and as we have a beautiful flowering Gum tree right in front of the property, it's like a heaving mass all over the nature strip, it sounds like its raining so many are smacking against the panes of glass.
Gillian 5 January, 2013 11:01
I live in Mt Waverley and had a plague of them on one corner of my house. I put a knee high stocking over the hose of a vacuum cleaner and secured it with a rubber band. When I switched on the cleaner all the beetles were sucked up into the stocking. Before turning off the cleaner I folded the loose end of the stocking back over the hose end, tied it and held it securely so it wouldn't be sucked back up the hose and switched off the vacuum cleaner. I've put the beetle filled stocking in a bottle and will wait until they die.
Discovery Centre 8 January, 2013 10:18
Hi Gillian, these beetles are a native species and can play an important role as plant pollinators but there is no law to say they can't be killed. Completely up to you but it might be nicer if you decide you want to kill them to place the stocking in the freezer which will quickly and relatively humanely kill them.
Helen 10 January, 2013 14:06
I have noticed 2 very large swarms on trees here at work. North Ryde, NSW. They only swarmed on 1 side of each tree. I Was concerned at first but thanks for all the information I will leave them alone and hopefully they will move on in the next few weeks. I have pictures if you want them.
anita marshall 11 January, 2013 11:19
We have just been invaded by the soldier beetle, we live in Budgeree Vic. They have made our huge Cheshnut tree their home,large limbs are weighted down by thousands of beetles all clumped together and when you shake the branch it looks like heavy rainfall. Now after 4 days they are flying around the garden. Amazing site.
Leila 11 January, 2013 12:32
I was quite happy to live out the plague at the end of the year that invaded my garden, however have now found that they have decimated my worm farm. Before I re-establish it, I am wanting to know how I can safely remove and dispose of the larve (along with what remains of my farm - castings and food). Any suggestions?
Discovery Centre 15 January, 2013 15:30
Hi Leila, the larvae of Plague Soldier Beetles are quite small and as far as we know would be too small to consume worms; and to our knowledge have not been implicated in this. Is it possible something else was responsible for the collapse of the worm farm?
Richard 17 January, 2013 22:46
There was a swarm of hundreds or thousands of them outside an office in Doncaster today. Great to see this harmless natural phenomenon in action in the suburbs.
Terry 19 January, 2013 07:45
My neighbour was talking about them yesterday as he has some on his property - he is wondering if these Soldier beetles are what he has always known by the common name of 'blister beetles' ? and a comment - I am constantly amazed, and saddened, by the number of people who seem unable to cope with the natural processes of nature when they impact on them - leave the poor creatures be, they'll be gone soon enough.
Discovery Centre 22 January, 2013 12:36
Hi Terry, Plague Soldier Beetles and Blister Beetles are different; the Soldier Beetles are from the beetle family Cantharidae and the Blister Beetles are from the family Meloidae. Some Blister Beetles (as the name implies) can cause blistering of human skin. Plague Soldier Beetles can release a distasteful chemical but it would only be a problem if you were to eat them. Good to see you are a fan of these native beetles.   
Craig 19 January, 2013 20:59
I'm into macro photography and great to read about these beetles. We have had a few hundred gathered on various plants but only during days where the temperature is in the high 30s. A friend on mine in early December had 4m of his gum tree covered in these - must have been thousands of them!
john 28 January, 2013 21:17
I live in Reservoir Victoria and am finding that the beetles seem to have impacted on my fruit and vegetable garden; sucking the 'juice' from plums, peaches, tomatoes. I applied soapy detergent and this seems to have helped in getting rid of them.
Discovery Centre 29 January, 2013 16:13
Hi John, it would be unlikely that the Plague Solider Beetles would be sucking the juices from your plants as when they are swarming their primary focus is usually mating. However, your treatment may have deterred something else that may have been causing some damage.
Dorothy 12 May, 2013 18:57
Hi John I live in the Riverina area, these pesky things were all over our grapes and figs and sucked them dry and what they didn't suck dry left a bitter taste on the fruit was not impressed, hope they don't return next season
Debbie 31 January, 2013 13:48
We have thousands of these beetles on a beautiful gum tree in the park next door to our house, they have been there for more than 4 weeks and have spent some time on the grass and some time on a smaller tree whose leaves are now dying, obviously the tree couldnt handle stress. Bit disconcerting when they fly into your mouth, hair and face as you walk in the park but our young boys are facinated with them. You knows when they will move on!
Jed 31 January, 2013 15:38
I've lived in the Upper Yarra for 23 years and never experienced anything like it! Hundreds of thousands of the little buggers literally 'raining' in our front yard from the neighbours' tall trees (including a huge lilli pilli) during mid-December – and they stuck around for a month or so. Earlier this month they started appearing in the primary school across the road and are still there in big numbers. Since I've never experienced this phenomenon before I'm starting to suspect there might be a connection with our exceptionally dry summer?
Buggered 1 February, 2013 12:41
Hi we also have thousands of them in our backyard and now I feel really bad considering how long they live for and they don't bite. I just massacred about ten thousand in one go. Am I going to heaven still??? They look like the stink bugs up in Queensland, our Little Jack Russel (GUS) is a Veteran Bug killer and he won't go near them. So I'm guessing if they aren't trying to sneak into the house or make the Mrs Scream they are ok, but if they come any closer and make my life hard, it's Asta La Vista Baby.
Mel Croker 2 February, 2013 14:28
We have been "plagued" for about 8 weeks around our house in the western suburbs I soon learnt they like white and caused me to have to bring in my white sheets I had just washed and hung on the line as they seemed to be laying lave on them. Everything had to be washed again no enjoying sitting in the back garden either. The sooner they go the better!
Emma 13 March, 2013 23:42
The CSIRO insect of the week site says: "The bright colours of Chauliognathus are a warning to any predator thinking of taking a swipe at one, as they exude a white viscous fluid from their glands that repels any predators thinking of getting too close. Close up image of the secreted fluid of a soldier beetle A close up view of the secreted fluid (Image Victoria Haritos) The soldier beetle also secretes the same chemical in a wax form to protect it’s eggs against infection. Our researchers have recently found the genes that give the chemical its anti-microbial and anti-cancer properties, and were able to replicate the synthesis in the lab. This may one day lead to the development of new anti-biotic and anti-cancer related products." So if you can, try not to kill these beetles, you can never be sure what a thing is really good for - these might save us from cancer one day! The CSIRO blog in full is here
Trevor Hopkins 25 March, 2013 11:50
We are at Lake Conjola NSW first time I have seen them here in 9 years of camping at this time of year. As you have said they seem to be mating by the thousands, hope they don't stay to long as the Easter break starts this weekend.
John 1 April, 2013 14:46
Hi, these are swarming at Phillip Island this long weekend. The house yard is off limits until they move on!!!
Kristy 2 April, 2013 15:44
I recently moved from frankston north to carrum downs and feel they have followed me:( however i havent seen the mass amount as i now have all over my front yard from the grass, to the concrete now they are slowly moving into my back yard and on my outdoor furniture on back decking. i have a phobia of bugs so its really getting to me that my 4 yr old son loves them collects them and wants them as pets and everyday they just seems to be more and more of them no matter the weather every day their there:(
Judith 2 April, 2013 19:10
These beatles are swarming in Queensland too. I live on the Darling Downs (in the country) and the eaves of our house are black at the moment. Have been now for a week. Like everyone else I hope they move on soon. We have been living here for 10 years and this is the first time we've had them like this.
Colin 3 April, 2013 15:50
Pascoe Vale Vic they love the silver car! Thanks for the info.
fernando 4 April, 2013 10:24
Richard 7 April, 2013 10:50
I too have these in my back garden in Berwick. They always come when my gum tree flowers. The ground is a mess with the broken gum nut things and the little hair like things that fall from the gum. The beetles are not a problem but the bees are lol. We have beautiful Rosellas in the gum & bats at night. At least I know what these beetles are now. Thanks.
Di 23 April, 2013 23:29
Exactly the same sceario here in dundas valley NSW . rather annoying as they leave yellow sperm all over the washing basket and on whites. The gum tree is in full flower and the bats are partying all night long .
Gary Leeson 7 April, 2013 11:50
We just had a swarm arrive last week that have grown in numbers and have taken up residence around our pond in Oatley (Sydney). They are having a great time!
julia 22 April, 2013 14:16
Im in Rowville, melbourne, and have tens of thousands of these in my yard....How do i get rid of them...they are all over my car as well... havnt seen them before this week....
Amanda 28 April, 2013 10:45
We have had quite a few in our backyard at Drouin over the last week. Not sure if the are eating the leaves of our chilli and jalapeño plants but they are annoying anyway. Seems every season there is a plague of some sort of different insect or bird, weird!
Martin 28 April, 2013 21:38
I caught a trout in the Kyneton area today and kept it to eat. Its stomach was packed full of beetles, mostly what look like soldier beetles. I guess they didn't taste bad to the trout. Do the beetles actually have a toxin in them? I ask because the trout ate the beetles and then I ate the trout....
Russell 29 April, 2013 14:26
I was wondering if you had any idea as to the length of time larvae of the Plague Soldier Beetles are in the ground before becoming an adult?
Vanessa 12 August, 2013 13:03
We arrived home from a holiday in the first week of April this year and found our house covered in them.During the very cold nights they seem to retreat in the roof and under the eaves and into the sheds then come out again during the warmer day. It is now August 12 and they show no signs or leaving-I hate them!!!
Judy 19 October, 2013 14:45
We have a property in Stanthorpe near the NSW/QLD border and arrived yesterday to see millions of them all over the grass. We don't have any flowering trees at the moment so not sure what's attracted them. I was happy to find this blog and the great comments from everyone - it has certainly put my mind at rest. Will just leave them alone until they are done with their spring frolicking.
Murray 5 November, 2013 17:22
A swarm arrived about a week ago at my place in Oatley NSW. They're congregating all over the balcony railings and external walls. I'm glad I saw this site as I was very curious as to what they are.
Emily 10 November, 2013 11:32
Are they considered a pest?
Discovery Centre 11 November, 2013 14:38
Hi Emily, as to whether they are a pest depends on your point of view. This native species is not a pest in terms of they don't bite people and they don't attack the timbers of peoples' homes. But for some the fact that they can arrive in your garden in large numbers and decide to stay for a period of time makes them a pest. 
Peter Holz 24 December, 2013 10:12
Our Escalonia hedge was covered in bees, but is now covered in soldier beetles. They appear to be keeping the bees off the plants and presumably out competing them for nectar and pollen. Is there anything that can be done about the beetles that won't also harm the bees, or do we just have to wait it out? Thanks.
Jeanette Evans 19 January, 2014 14:55
These bettles are eating my corn and tomatoes by the thousands, have not been able to eat any, so on another site I read to spray with orange scented dish detergent mixed with water which I have just done loved to see them run away, I will be spraying everyday till they all gone may take awhile
Samantha 28 January, 2014 19:55
Live in wantirna Victoria and masses in clumps around bottom of every tree trunk on our property. Gums, pines, yakka, and pottostrums. Been here now for three months and getting worse !!!!!!!!! Leaves are falling off the pittosporum trees is this because of these beetles.
Debbie 9 February, 2014 17:13
A swarm has just descended onto our chicken coop. With 2 one week old chickens inside, (the beetles have moved inside too), I am hoping they will not be a problem to them? Does their arrival have anything to do with an outbreak of mites we had also? Will the beetles eat the mites? Just loving country life!
Discovery Centre 12 February, 2014 15:23
Hi Debbie, when the beetles gather like this it is generally a mating swarm so their principal preoccupation is going to be mating rather than eating. What usually happens is a few beetles pick a spot and release pheromones which attracts others until you get these sometimes huge gatherings. I doubt they'll pose a risk to the chickens, their bright colouration serves as a warning that they are distasteful. 
Neil 17 March, 2014 18:17
A swarm has turned up in Knoxfield and was a bit frightening as they would fall onto girls long hair from the trees and the gutters over the back door. Your site would be about the best we have ever recived help from. Keep up the great work (and hope they go soon, having trouble getting out back door).
Yvette 24 March, 2014 23:18
I have read all previous comments and take it that these beetles love big trees. I have a lot out the front and they have been there for over a month now. I know you have said they're here from Spring until summer, but some people are getting them in Autumn and Winter? Is there any reason for this? Has their life span been researched? Also, I have not seen these beetles before and I have read a few other people have as well.. Any answer on where they may have come from? Why are these beetles so popular now? Thank you for all the information on these bugs. Glad to know they're not harmful and native! Oh, and also great to know I'm not the only one experiencing this plague (:
Janelle 28 October, 2014 07:19
Hi, I'm in laidley , qld and we have a massive swarm in the tree next to our laundry door !! Is there any way to stop them coming in the house as getting home and finding a whole garage and living room full of them last night was not something I'm fond of ;) also I notice they are mainly in vic and nsw , is it common to find them in qld ?
Discovery Centre 1 November, 2014 11:04

Hi Janelle, I have been having a look at registered museum specimens for this species and you are correct that the majority of the records tend to be south-eastern Australia but there are some museum records of this species from south-eastern Queensland. In terms of moving them on that can be difficult as the females release a pheromone to attract the males. The sole purpose of these swarms is to mate and they are pretty hard to dissuade.

Bec 9 December, 2014 10:48
We have millions of these beetles infesting a flowering gum in Springwood NSW (blue mountains). They arrived 4 days ago just seem to be increasing in numbers every day! It is quite incredible, every leaf on the 100ft+ gum is black with them and they are also on all the other trees and plants in my front yard, I have never seen anything like it! I hope they move on soon, I'd like to park my car in the driveway again rather than half way up the street!
jo 11 December, 2014 12:22
Hey Bec, same here, we have millions in Springwood NSW in our big gum, all over our yard, car, washing line etc. We are past the novelty of them too now, I just went to post office & the lady there told me there were 2 crawling in my hair! Alas, all part of nature. Good to hear someone else in the hood has experienced the same thing.
Jennie Towan 22 March, 2015 14:15
Just wondering if these beetles are likely to damage a croquet lawn? Noticed a few here at croquet this morning in Lakes Entrance. Thanks.
Brigette W 25 January, 2016 13:36
I have thousands swarming my front yard in Sunbury, Victoria. Good to know they are ok but highly annoying trying to walk to the car. Been around for a few days now.
Carlene 27 February, 2016 11:39
We have them in my pumpkin patch. Thought I'd lost all my pumpkins to them.
Carlene 27 February, 2016 11:41
Forgot to add, we are in Wodonga.
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