A new study conducted by researchers at the University of Helsinki emphasises the important role of low-intensity cattle grazing in maintaining biodiversity on modern farms.
Grazing is regarded as one particularly beneficial practice to biodiversity on farms, especially if it is practised on natural pastures in traditional ways.
The large-scale study, which surveyed over 40 dairy and beef cattle farms across southern Finland, demonstrates that extensive grazing practices can benefit the diversity of ground-dwelling arthropods, even on intensively cultivated agricultural grasslands. The findings provide valuable insights into balancing agricultural production and sustaining biodiversity on farmland in modern grassland systems. The importance of this comes to light when considering the population declines of several insect groups on farmland [*] and the important ecosystem services they provide, such as nutrient cycling or pollination.
Farms practising low-intensity grazing see the highest levels of arthropod diversity, particularly among ground-dwelling species. This highlights the ecological importance of grazing as a tool for maintaining farmland biodiversity.
Unlike traditional natural pastures, over 90% of grasslands in Finland are part of crop rotations. The study found that grazed rotational grasslands support higher arthropod diversity compared with mown grasslands or cereal crops, but only when grazing is conducted at low intensities, which in this study means a small number of cattle on a farm in relation to the farm’s pasture area.
Furthermore, organic farms showed higher arthropod diversity than conventional farms, but this benefit was only observed when low-intensity grazing was practised.
Challenges and trade-offs

According to researchers, modern cattle grazing faces certain limitations for maintaining biodiversity in regions like Finland, where agricultural land use has intensified. While grazing benefits biodiversity, it may lead to reduced production levels. This trade-off needs to be acknowledged and addressed when designing solutions to balance food production with ecosystem services.
"Our study makes a unique contribution to the limited evidence regarding the ecological state of rotational grasslands and the biodiversity benefits of cattle grazing on modern dairy and beef farms. While indoor housing of milking cows and intensive grassland use for silage may boost production, they can significantly reduce biodiversity on cattle farms, potentially to levels comparable to farms without cattle," says Dr. Iryna Herzon, senior lecturer in agroecology at the University of Helsinki and lead researcher of the study.
Pathways to sustainable livestock farming

Researchers suggest several strategies for livestock farmers to enhance biodiversity on their farms:

1. Prioritise grazing over indoor housing: Grazing cattle on pastures, even rotational grasslands, is a critical first step to maintaining arthropod populations.
2. Support extensive grazing areas: Farms with low-intensity grazing areas, where cattle are kept at low density to create diversity in vegetation, provide essential habitats for arthropods and other wildlife.
3. Economic and policy support: To offset potential reductions in production output, milk from grazing cows could be priced higher, or public support could be provided to incentivise biodiversity-friendly practices.

"Considering the large environmental impacts of animal production, the future of livestock farming must move towards producing less but better animal products. Sustainable grazing practices are a vital part of this transition," Dr. Herzon concludes.

[*] Major reasons for the decline in insect populations in Finland are intensive forestry and farming, where traditional forms of grazing on natural pastures continues declining, according to the most recent evaluation of threatened species. Red Data Book of Finland.