This week my family embarked on a fascinating field trip to the world of Dung Beetles at Dung Beetle Innovations in Whenuapai. It was really interesting meeting Shaun Forgie and hearing about his passion to improve soil health and farm management systems in New Zealand. Shaun supplies beetle colonies that are suitable for thriving in conditions from Cape Reinga to Bluff. Whilst we were there, a busy hive of activity was taking place in the background tending to the many “beetle beds” which resemble raised garden beds. These beds are supplied with specialised premium soil from Matamata to establish larvae and efficiently harvest mature beetles. They must be kept constantly fed with fresh local dairy cow manure which is very labour intensive, particularly in our current wet conditions!
Shaun and his team package up colonies of beetles and can ship them across New Zealand with specific instructions for establishing your new beetles. There are different species options depending on the needs of different farms, their stock units and location. Diversity is the key to providing all year-round soil health and manure management.
Beetles may take a few years to establish, and you may be wondering if they’ve packed up and left home sometimes! However by year 2 to 3 you will start to see their presence and within 5 to 10 years soil and pasture health and manure management will have significantly improved.
It is very obvious when Shaun showed us cross section examples of beetle tunnels, that these wee guys are hugely beneficial when it comes to improving soil drainage and aerating our land. What you can’t see with the naked eye are all the other benefits. Beetles will bury nitrogen and phosphorus extracted from manure to specific depths that just happen to be ideal for fertilising pasture. They are like a team of mini Massey Fergusons.
Introducing beetles to New Zealand was a difficult process and it was important to provide evidence that they would not cause any harm to our unique flora and fauna. We do have several species of native beetles, but they have evolved for bush conditions to feed from our native wildlife manure and are not so useful for agricultural purposes.
There are 3 main types of beetle. Dwellers, Rollers and Tunnellers. Tunnellers are the most beneficial for improving soil quality, particularly compacted poorly aerated ground and it is this group of beetles that are focussed on at Dung Beetle Innovations. Each tunnelling beetle will excavate tunnels to specific depths depending on the species. Some may be as shallow as 10-20cm whilst others can tunnel to over 1m.
I found it endearing that once the male and female beetle have paired up, they share the excavation and preparation of the tunnels together. Dung balls are prepared once the tunnels are ready and usually one fertilised egg per ball is deposited. Multiple dung balls will exist per tunnel and these are filled with manure to act as a food source for the emerging adult. The dung balls are very robust and provide refugia for the stages of development from egg to larvae to pupa to adult. When the adult emerges from the ball about 2/3 of the shell is left behind which encourages root growth and promotes healthy microbes, earthworms etc to thrive. It is staggering to think of the amount of carbon, nitrogen and phosphorus re-introduced to the soil in this way.
Some studies have been conducted into the potential for dung beetles to significantly reduce methane gas emissions through these processes. Results look promising, however more research is required in this space.
As you can imagine with hundreds of tiny tunnels being introduced across your paddocks this results in reduced run off from rainfall into our precious waterways. Potentially harmful dung, urine and agricultural chemicals are kept locked in the land instead of aquatic ecosystems!
The more you look into dung beetles its actually mind blowing how beneficial they are for the agricultural sector. The thing that drew me to them many decades ago now, as a fresh new graduate in Victoria, Australia, was their ability to reduce reinfection rates of parasites on pasture by interrupting their lifecycle. This applies to many pests including the cluster flies we all put up with during summer, but for me of course the effect on internal parasites of the horse was of most interest.
Beetles will disrupt the lifecycle of common internal parasites of horses in 4 main ways:
As they process manure they will physically disrupt and damage eggs and larvae with their claws so they are no longer viable.
During the process of dung feeding, they will ingest and kill eggs and larvae with their digestive processes.
They will dry out or desiccate the manure as they spread it and organise it. This exposes eggs and larvae which require a film of moisture for development reducing their viability.
Finally they will bury the manure, taking eggs and larvae with them and preventing exposure to grazing animals.
So cool!
How does Worm-Ed support Beetle Health?
As we have developed and refined our Worm-Ed programme over the years and acknowledged the critical role dung beetles play in reducing pasture re-infection rates, I have been trying to cater to best practice management of beetles along the way too. It has been so interesting to see that our strategies for reducing the acceleration of dewormer/drench resistance tie in beautifully with protecting beetles.
One of the main concerns for horse owners with beetles is minimising exposure to chemical de-wormers when required. Beetles are actually relatively hardy and will tolerate exposure to de-wormers if used strategically. There are some classes of de-wormer known as the “BZs” (benzimidazoles), such as Panacur and Bomatak that may be kinder to beetles but have less efficacy against strongyle worms. Conversely the mectin group of de-wormers, such as ivermectin, abamectin and moxidectin have greater efficacy in general against strongyle worms but they are potentially more harmful for the beetle. How do we look after horse and beetle health???
We also have 4 main ways to protect beetles whilst maximising horse health:
Using diagnostic based treatment programmes through faecal egg counting (FEC) and only treating horses above a certain threshold. This is measured in eggs per gram of faeces (EPG). We can take this further by identifying different egg shedder types of horses. Horses will broadly fall into 3 categories of shedder type: High, Moderate or Low shedders. Given that 50% of horses are low egg shedders and recommendations for this group is only 1 to 2 de-worming treatments per year, we can instantly see the benefits for the beetles with this Targeted Selective Treatment approach.
Providing “refugia” from treatment. Allowing a source of refuge by not exposing worms to treatment at certain times of the year means that we are reducing the selection pressure for de-wormer/drench resistance but also reducing the chemical load on our whole ecosystem including the beetle and aquatic species.
Performing Faecal Egg Count Reduction Trials (FECRT) this is a mini study on your farm to see which wormers are performing well for you. If the worms on your property are susceptible to the kinder “BZ” group of de-wormers, then why not use them! This is just generally such good practice to perform a FECRT every few years to check in on how products are working for the health of your horses anyway.
Finally, staggering treatments across the herd so we are always providing chemical free manure for feeding at any one time. This ties in with the targeted selective treatment mentioned above. At certain times of the year however it may be recommended that the whole herd do need treatments. We are now recommending staggering those treatments across a few eeks for multi horse properties. We also recommend picking up and disposing of manure from treated horses for the first 72 hours.
On a final note, with all the rain we have had lately many people have been concerned about their beetles drowning. After holding one of the dung beetle balls at Dung Beetle Innovations you can appreciate how solid and robust they are! They are a cozy, safe and dry little home and there is no danger of them flooding
Well, that ends my summary of our fascinating field trip. If you are interested in raising beetles on your farm, get in touch with Shaun at www.dungbeetles.co.nz
