Interview with the authors of The Little Owl

The Little Owl, Athene noctua, is one of the most well-studied species of owl. Despite being widespread across Europe, Asia and North Africa, populations are now in decline, making studies of its behaviour and ecology all the more important. The revised second edition of The Little Owl, which vastly expands on the original, published in 2011, covers everything you could wish to know about the species. From its history, taxonomy and genetics, to details of its habits, diet and breeding, the wide-ranging text consolidates all of the current available knowledge, obtained both from the author’s personal experience and research, as well as scientific and conservation literature.

The authors, Dries van Nieuwenhuyse, Ronald van Harxen and David H Johnson generously gave up some of their time to answer our questions about the book, the issues currently affecting Little Owls globally, and their hopes for the future of this captivating species. The Q&A is also illustrated with some of the beautiful images from the book, all of which were created by scientific illustrator and graphic designer Joris De Raedt.


Firstly, can you tell us a little bit about yourselves and the work you are currently involved in?

Dries is a life-long owl researcher and statistician active in ecological method development and publication. He has authored five books on the impact of technology and statistics on the decision-making processes of organisations, and in particular brings his skills as a statistician to his ornithological work.

Ronald is Chairman of the Dutch Little Owl Working Group (STONE), and has been active in research on breeding biology and population dynamics within nest box populations and conservation of the Little Owl in the Netherlands and internationally for more than four decades.

David is Executive Director at Global Owl Project, USA and working since more than a decade on a demographic study of the Burrowing Owl (Athene cunicularia). He has worked in natural resource conservation for four decades and has written two previous books on owls, wildlife and fisheries.

Joris De Raedt is scientific illustrator and graphic designer
visualising the wonders of the natural world. He illustrated the book through a combination of graphite sketches and digital illustrations. Color and details are added on the computer using a graphic tablet. More on his workflow at jorisderaedt.com.

For anyone that enjoyed reading the first version of The Little Owl which was published in 2011, what new things can they expect to discover in this updated second edition?

The subtitle of the first edition was Conservation, Ecology and Behavior, the second edition paid special attention to Taxonomy, Population Dynamics and Management. Major improvements are the illustrations that were all created by Joris De Raedt. This allowed us to make compilations of photos of the subspecies and their habitats to obtain extremely detailed and standardised artistic plates. The fact that this edition is in colour allowed excellent drawings of the embryonic development, the evolution of nestlings in function of age and high quality distribution maps by country and globally. The global distribution map was revised with much more accurate data than even before, thanks to the internet and technological advances.

Plenty of new insights were brought in by Ronald on breeding biology, prey items and behaviour in nestboxes that were equipped with webcams. Photos led to video, and that led to online webcam data that was tagged with time, prey species and specific behavior by volunteers.

The final major evolution was the intensification of replicated experiments since the first edition. Crucial questions on the yellowness of the beak of the female in relation to breeding performance and feeding preference of female nestlings by females, and also in relation to the yellowness of the beaks of the offspring, led to major breakthroughs in our knowledge. Due to the publication of the first edition, the start of a pdf and citizen science website for data collection improved the international cooperation tremendously and facilitated access to international data bases of ringing data, geocoded pictures and vocalisations.

Historically the Little Owl has suffered due to intensive agriculture practices and abundant use of pesticides. Are Little Owls still widely affected by these issues, and do we yet have a clear idea of how they are likely to be impacted with the additional challenges posed by the climate crisis?

Little Owls are ambassadors of small-scale landscapes. In some countries they disappear due to intensification of the agriculture, while in other countries they disappear when farming is halted (grazing cattle disappear) and after forestation. Climate change is expected to have a positive impact on the species in the north and the east due to less snow cover. Increasing heavy rain during the breeding season, on the other hand, will probably have a negative impact on breeding success. Increase in desertification might not be an issue, as this typical Mediterranean species can even be found in the Sahara and the Arabian Peninsula. In Europe, most negative impacts comes from agricultural intensification, with an increase in maize leading to less grassland, increase in pesticides and rodenticides, increase in scale of the landscape with fewer parcel borders, fences or shrubs.

An important part of the book deals with management techniques that have proven to work over the long term. Reintroducing short grassy vegetation with commanding perches and provision of nestboxes can significantly help Little Owls to cope with modern agriculture. If conservation is started timely enough, this simple management can help preserve healthy populations. When densities drop too low, this might not be sufficient and, in combination with a lack of food, can lead to local extinctions.

What are the key ways in which Little Owls are surveyed? And how comprehensive is our knowledge of where they occur and their current population sizes?

The species is excellent for research due to its easy response to playback of vocalisations, historically mostly undertaken in western Europe but recently increasing in eastern Europe. Monitoring efforts have continued since the 1980s and offer a good view on population numbers. This has led to extra research on the possible impact of habitat deterioration, food availability and the increase of Stone Marten and Tawny Owls as possible limiting factors.

Since the first edition plenty of new local and large scale atlases have been published leading to a very detailed knowledge on the distribution and population numbers in Europe. The new EBCC atlas has distribution data at the 50 by 50km level, the 27 EU member states monitor Little Owl presence at the 10 by 10km level, and a number of local atlases have data available at the 1 by 1 km level.

Outside of Europe, the species is rather common but distribution knowledge remains anecdotal with population estimates largely based on local average densities and, in rare cases, on habitat modelling. More insights emerged from North Africa and the East (eg Iran and Pakistan) but much more work is still needed outside Europe. Hopefully this book can boost research in less well-studied countries, as many methods that have proven to be working simply need to be replicated elsewhere.

How effective have captive breeding and reintroduction projects been for the Little Owl so far? And is this approach likely to be an important one for their future conservation?

Not very effective. Some initiatives have been undertaken but with moderate outcomes. Reintroduction remains an emergency brake that rarely works. Supplemental feeding, provision of nestboxes and landscape improvements are much more effective, particularly when they are started in a timely manner. The key is not to wait too long before starting with small-scale management and to keep healthy populations, even in areas with intensive agriculture.

How likely are Little Owls to utilise artificial nestboxes?

Very likely, and this makes The Little Owl one of the best and easiest models for biological and conservation research. The ease of installing nestboxes with webcams and with predator protection allows data to be collected in an unprecedented manner, without special tools or tedious field work. People can observe the species seated at their kitchen table, youngsters can easily be involved in playback monitoring, nestbox maintenance and food supplementation, which eventually leads to experiments and dedicated citizen science. This make the species so special.

Finally, what’s next for you? Are there new books on the horizon?

Sure, Ronald and Dries will publish a non-scientific version of the book in Dutch for the 2000+ local volunteers to thank them for their tremendous help in collecting and digitising Little Owl data through conservation, management and ringing. David and Dries are currently preparing a similar book on the close relative of the Little Owl, the Burrowing Owl. Finally, Ronald is currently working on a book on all owl species that can be found in The Netherlands. We’ve still got some work to do.


The Little Owl by Dries van Nieuwenhuyse, Ronald van Harxen and David H. Johnson was published by Cambridge University Press in October 2023 and is available from nhbs.com.