British dung beetles – here to help

Author: Ceri Watkins, Co-Founder of Dung beetle UK Mapping Project

Species: Dung beetles

Why is farmland important for these species?

There are approximately 60 species of dung beetle in the UK. They are not the ‘ball rollers’ seen in warmer countries and on TV, instead they live inside the dung pile (dwellers) or in the soil beneath it (tunnellers). Livestock grazing provides much of the dung required for the survival of these beetles, although other animals such deer and badgers also contribute. Some species are rather specialised and require exacting conditions. For example, Volinus sticticus prefers horse or sheep dung in the shade and Onthophagus joannae is a sun loving beetle that favours sheep dung on light soils. Others are less fussy and have few specific requirements.

It is possible to find dung beetles at work all year round. Several species are winter active, although the vast majority are found in the spring, summer and autumn. Given the right conditions, dung beetles can decimate a pile of horse poo or a cow pat in just a couple of days.

Volinus sticticus (c) Katherine Child  

Onthophagus joannae (c) Katherine Child

How do dung beetles benefit farms?

Dung beetles provide a wide range of ecosystem services that help to maintain healthy pastures and soils. These include the most obvious, the consumption of dung thereby removing it from the fields thus reducing pasture fouling, but also some that you may not have considered. As the beetles tunnel down through the soil, burying the dung for breeding purposes, essential nutrients are recycled within the soil profile. This improves grass growth and provides a direct benefit to grazing animals. The larger species such as the Minotaur beetle (Typhaeus typhoeus) can tunnel a metre or more, this action breaks up the ground and improves drainage, especially useful on clay soils.

In addition, dung beetles also reduce nuisance fly populations by transporting phoretic mites that eat fly eggs and help control intestinal parasites by reducing dung suitability for worm larvae. The beetles are also an important food source for many other farmland favourites such as bats and birds.

 

Onthophagus similis with phoretic mites (c) Ceri Watkins

Habitat management

Continuity of the dung supply and diversity of habitat are key factors in supporting a diverse range of dung beetle species on the farm. If possible, maintain some outdoor grazing year-round, even if only a few animals. Planting a group of trees and grazing within them will provide variety of forage and shelter for livestock and support the shade loving dung beetles too.

Broad spectrum livestock wormers such as avermectin are detrimental to beneficial dung invertebrates. These chemicals are excreted in the dung for many weeks after treatment and a range of lethal and sub-lethal effects occur depending on the concentration. Such effects include slowing beetle larvae development, reducing the size attained at adulthood and reduced breeding capacity.

Dung beetle larvae (dwellers) (c) Darren Mann

Cutting down the use of chemicals on the farm with a sustainable worm control policy that includes monitoring with faecal egg counts will help. Treating animals only when necessary will save money and also slow the rate of anthelmintic resistance. As a natural alternative in a rotational system, consider using herbal leys. Sainfoin, birdsfoot trefoil and chicory all have anthelmintic properties. The latter has been shown to reduce worm burden in sheep by as much as 40%. In permanent grasslands, mixing up cattle and sheep grazing works by reducing the stocking density of the parasite host – cattle and sheep worms are different species.

Benefits

Supporting dung beetles on your farm not only helps keep pasture and livestock healthy, it also represents good economic sense. It has been estimated that dung beetles save the UK cattle industry £367 million per annum through the provision of ecosystem services (Beynon et al., 2015). So, it really does pay to look after these useful little creatures.

For further information and dung beetle identification resources, please visit the Dung beetle UK Mapping Project website or get in touch via email or twitter.

Case study: Herb-rich leys

Author: Ian Boyd
Farm: Whittington Lodge Farm, Gloucestershire

Aims:

Whittington Lodge Farm has predominately thin Cotswold Brash soils on 280ha, mostly over 800 feet in altitude. The cultivated half of the farm was in a continuous arable system, but average yields meant it was only marginally viable and blackgrass was creeping in.

In 2015, it was decided to undergo organic conversion on all the arable area to combine with the fully organic grassland. Herb-rich leys were introduced into the rotation to build fertility for the organic cereals. They are grazed by an existing and expanded suckler herd of native Hereford cows and calves.

Cattle grazing a herb-rich ley at Whittington Lodge Farm. Image credit: Ian Boyd

Management:

The herb-rich leys contain at least 5 species of grass, 5 legumes and 5 herbs which all add to the biodiversity with varying rooting depth in the shallow soils. They are established by under-sowing in spring barley crops, broadcast with an Opico seeder/harrow once the barley plants have reached the 3 leaf stage. This way the undersown plants are still small enough not to interfere with the barley combining. Grazing can begin in the autumn.

The herb-rich ley can last for 4 years and can be grazed or conserved as hay or silage. It can fit in well with other grasslands like permanent pasture with the management of grazing livestock.

Mob grazing can help achieve the best from the leys. The cattle are moved frequently, usually daily, onto fresh grazing and a back fence stops them eating any re-growth after about 3 days. The adage is that you should not see the cattle’s knees when they go in and you should not see their ankles when they come out. Some of the herbage is eaten, some trampled and some left so that the root structure underneath the plants is maintained and re-growth is rapid.

Then, most importantly, the ley is rested for a couple of months to allow plants to flower and set seed before the next grazing. This will provide habitat for invertebrates, including crop pollinators, and improve soil structure and water infiltration.

Moving the electric fence is a daily commitment but it makes it easier to check and count the stock as they run past.

The cost of seed is significant but no nitrogen is required, and it is possible to incorporate this option into a Countryside Stewardship scheme and claim payments for it.

As the soil organic matter level is improved, more grass will be grown and stocking rates will be able to be increased. This system suits both cattle and sheep on organic and non-organic farms.

Achievements:

There are multiple benefits to herb-rich leys. When terminated, they provide an ideal entry to cereal crops for several years, organic or not. The arable weed spectrum is dramatically reduced, especially blackgrass.
Soil health and organic matters levels will have been increased with large amounts of carbon sequestered into the soil, far more than the effects of methane produced by the cattle.

The nutrient density of the beef will be greater when multiple species and biodiversity are eaten with knock-on health benefits for the cattle and consumer.

The farmland wildlife is a big winner here, with many different plants flowering producing nectar for pollinating insects and producing seed (and insects) for many bird species to eat. Skylarks nest everywhere, hares and roe deer love to graze it. Kestrels and barn owls hunt for short-tailed field voles living in the long grass and snipe are increasingly being seen looking for worms in the winter time.

It really helps to be organised and to have planned the rotational grazing before the start of the season. Access to water, ease of moving electric fences and having the cattle in the right place at the right date all have to be factored in.

This system really suits British native breeds of cattle, which can readily be managed to Pasture-for-Life standards (essentially no grain fed). Pasture-for-Life beef allows the opportunity to brand and market it yourself with a great story for a higher price than the beef commodity market can pay.

www.cotswoldbeef.com