Chaco Owl EEP

The Chaco owl (Strix chacoensis) (is a small owl from Bolivia, Argentina and Paraguay. It is currently classified as Near Threatened but continual population declines, and poor mitigation actions suggest that a reduction to a ‘Vulnerable’ status is expected (Birdlife International, 2020).

The Chaco Owl EEP was established in October 2023. With the Regional Species Plan, defining Insurance, Education and Funding conservation roles.

There is only thtee EAZA collections holding this species, but there are many owned by non EAZA zoos, raptor centres and private breeders in the UK, Netherlands, Italy and Germany. The priority is to identify birds, develop relationships with holders and investigate ways to establish an EEP with sufficient birds for the population to be demographically, genetically and behaviourally competent and stable.

Chaco Owl EEP briefing sheet has been produced to explain to non-EAZA holders how they can participate with the EEP and be part of it as a non-EAZA member. There is a major misconception that EEPS just want to ‘take their birds’ for nothing in return so confidence building to ensure that holders understand the EEP will work in partnership is essential. This approach has resulted in 4 collections holding Chaco Owl asking to join the EEP as Non- EAZA Members and two collections agreeing to generously donate birds to the programme. Expanding this work to other European countries is the next step and assistance from members would be greatly appreciated.

Chaco Owl are an attractive species, display well and are not difficult to manage and therefore are a valuable species for conservation education.

The principal threat to Chao Owls is is the massive scale deforestation and conversion of land to soya production and cattle ranches (Tracewski et al. 2016, Bodrati et al, 2017)). This is making the Chaco ecosystem even more threatened than the Atlantic rain forest, The meat is exported to Europe, therefore as European consumers, we are indirectly responsible for the destruction of this habitat. This habitat loss is also impacting on other species EAZA collections hold and conserve such as the Chacoan Peccary and Giant Anteater, so the Chaco owl provides opportunity to educate on ecosystem affects and impacts.

A Chaco Owl fact sheet for containing key information about the species and the threats it is facing has been produced and is in use by holders to create displays, signage and a scripts for flying displays and interactive sessions.

Unfortunately, the conservation of owls is made more complex by the near total lack of knowledge of their reproductive biology, habitat requirements, and diet, making it difficult to propose effective conservation strategies to combat the challenges posed to them by the modern world (Bodrati et al, 2017) Conservation non-governmental organization Zoo and Wildlife Conservation is working with Fundacion Para la Tierra to establish a research programme in Paraguay’s dry Chaco to develop an understanding of the ecological and conservation needs of the species.

This project aims to start addressing the research needs identified for effective conservation planning for the species, these are population size, distribution and trends, life history and ecology and threats (Birdlife International, 2020).

Three field trips to the Central Chaco of Paraguay will be made each year in February, July and October to allow for study of seasonal variation in range, habitat use, diet and breeding behaviour.

Populations will be estimated by undertaking mist netting. All individuals will be banded and morphological data recorded. GPS locations will be recorded and an assessment of the habitat at the netting location will be made. To investigate home ranges and habitat use, individuals will be tagged with remote download solar GPS TAGs. Diet will be investigated by locating nests and roosts and pellets will be collected and examined as described by (Santander,et al, 2012). Breeding and feeding behaviour will be monitored through the use of camera traps and, breeding success will be monitored.

Non- EAZA EEP participant Baytree Owls has produced and education poster with a QR code donation function which are now being used in 6 zoos in the UK. This consortium of current non-EAZA Chaco Owl holders has now raised sufficient funds to establish the filed project in Paraguay. The first trip is scheduled to take place in February 2026, but we need ongoing support to continue this exciting field conservation project.

For more information, if your collection holds Chaco Owl and you would like to be part of the managed programme or if your zoo would like to hold Chaco Owl please contact me.