Small fields, great diversity: How a diverse patchwork of crops helps birds

Birds are not only beautiful to look at and listen to; they also play important roles in nature. They eat pests and disperse seeds. They are generally considered indicators of a healthy environment. When birds thrive, soil and water quality often benefit as well. A new study published in the journal Landscape Ecology shows that growing a variety of crops in small field patches creates better habitats for birds.

The study was led by the Leibniz Centre for Agricultural Landscape Research (ZALF). Over three years, the scientists investigated how growing a variety of crops in small patches within a field affects bird populations. Birds visited the experimental field about 70% more often than neighboring, conventionally managed large reference fields. The result is clear: Where fewer pesticides are used and different crops grow close to one another, birds feel more at home and are more abundant. The paper is published in the journal Landscape Ecology.

The analysis found that birds were not only encountered more often in the diversely managed fields but also behaved differently. They formed small groups and preferred areas with lower pesticide use and greater plant diversity. The skylark in particular—a bird that nests in open areas and is often considered an emblem of the agricultural landscape—benefited from these conditions. It was found significantly more often in areas with less chemical pesticide use, adjacent flower strips and more wild plants.

“Our data clearly show that it’s not just about what is cropped, but also how the land is designed and managed,” explains Jenny Kröcher, a researcher on the ZALF team. “If we make the fields smaller, combine different crops, and—wherever it is possible—reduce chemical crop protection or replace it with non-chemical methods, we create habitats that provide birds with food and shelter. It’s like a buffet and a safety net all in one.” Other research groups have reached similar conclusions: A diverse landscape is more resilient and richer in species.

What makes this study distinctive is its consideration of the entire landscape mosaic, rather than individual measures alone. While other studies often examine only the effect of individual wildflower strips, the patchCROP experiment shows how small field patches, different crops and sustainable pest management work together. The results confirm earlier observations but, thanks to the high spatial resolution of the data, provide a more detailed picture.

The “patchCROP” experiment was at the heart of the study. In this experiment, many small patches were combined within a large field, with different crops grown and various management methods applied. For comparison, researchers observed neighboring large fields managed using conventional methods. From September 2020 to August 2023, they mapped all birds observed on the small patches and on nearby control areas.

This analysis was made possible by a method that has rarely been applied to bird data in this way: “Spatial Point Pattern Analysis” (SPPA). Research conducted on working farmland is difficult to evaluate by conventional scientific standards. Unlike in a controlled field experiment, there are no identical, independent replicate plots—each patch occupies a different position in the landscape and differs in its surroundings or soil conditions. Conventional statistical methods, however, require such comparable replicates.

The SPPA method works around this problem by using the spatial distribution of the observations themselves, rather than predefined comparison plots, to examine whether the distribution is random or reveals patterns. This allows researchers to consider environmental factors—such as the use of plant protection products, soil conditions and vegetation structure—simultaneously and distinguish their effects. The study thus shows that reliable scientific conclusions can be drawn even from real-world field trials without replicate plots—an approach that could put future research on farmland on a more scientifically sound footing.

How can these results be applied in practice?

Growing a wider variety of crops across many smaller fields or in patches is difficult with the large machinery currently in use. That could change as autonomous field robots become ready for practical use, as is also being tested in the patchCROP experiment.

Integrating nature conservation into cultivated land, as demonstrated by the patchCROP approach, offers a promising way to combine food security with species conservation. Further research is needed to clarify how these systems will affect farm profitability in the long term and how they can be adopted widely.

Who’s behind this story?

Gaby Clark

MA in English, copy editor since 2021 with experience in higher education and health content. Dedicated to trustworthy science news.

Full profile →

Andrew Zinin

Master’s in physics with research experience. Long-time science news enthusiast. Plays key role in Science X’s editorial success.

Full profile →