The Barn Owl colour ringing project has already provided valuable insights, including some notable sightings (see photograph) and unfortunate recoveries of birds that have perished.

The main aim of this project is to better understand Barn Owl chick dispersal, which is generally believed to be relatively limited, with most movements falling between 9 and 14 km from their natal sites. However, the first year of a Barn Owl’s life is particularly perilous, with studies indicating that around 70% of juveniles do not survive beyond their first year. Many face significant threats after dispersal, which is evident from our findings.

Summary of Results Since August 2024:

Sightings:

• • 4 sightings have been reported:

• • • Two birds were observed fledging and hunting near their nest boxes, eventually dispersing when they became proficient hunters.
    • One chick, ringed near Burton Mill Pond, was later spotted near Lavington, a 5 km journey.
    • Another Barn Owl, ringed on 21st June near Cranleigh, was seen at Beeding Brooks on 17th August, marking an impressive 40 km movement. Female ADJ, see image.

Recoveries:

• • 7 recoveries have been recorded, highlighting some of the key threats Barn Owls face:

• • • 2 road traffic accidents, both within 2 to 4 km of their natal sites, show how vulnerable young owls are to collisions, especially when hunting low over roads.
    • 2 electrocution incidents on power lines, 3 to 4 km from natal sites, further emphasize the danger of human infrastructure.
    • 3 unknown causes, with 2 of the birds later found predated. One of these, a chick ringed on 12th July near Storrington, was recovered on 11th October at Sandy Point Nature Reserve on Hayling Island, having travelled 46 km.

These incidents underscore the numerous dangers young Barn Owls face, including collision with road or rail traffic and electrocution which are the leading causes of mortality during the vulnerable first year after fledging. Other significant threats include accidental drowning in uncovered cattle troughs and the ingestion of poisoned rodents, which can lead to secondary poisoning and death.

Reporting Sightings:

As winter approaches and prey becomes scarcer, Barn Owls will likely become more active during daylight hours to compensate for the reduced availability of food. This increased daytime activity presents greater opportunities for sightings. We encourage everyone to keep an eye out for colour-ringed Barn Owls, which can be identified by a red ring with white letters on their left leg. If you spot one, please report it to us at info@sussexbarnowlgroup.org

2024 monitoring and ringing effort.

We found a slight increase in records of early broods this year with 77% of chicks ringed in the last 2 weeks of June and the first 2 weeks of July. Brood sizes were the smallest encountered from the time there has been consistency in monitoring since 2020, (viz 2.5, 3.2, 2.6, 2.5, 2.4). The wet late winter and early spring may have led to difficulty in hunting, which did not allow females to put on the weight necessary to lay larger clutches (pers obs).

However, from the 200+ boxes visited by ringers and Schedule 1 agents we found a 48% Barn Owl occupancy – the highest for 5 years.

125 boxes in total were occupied as follows:

94 by Barn Owls, 90 of which contained breeding birds. Other occupants included Stock Dove Columba Oenus, (19 boxes). Western Jackdaw Corvus Mondella (8 boxes). Common Kestrel Falco Tinnunculus (2 boxes). Tawny Owl Strix Aluco. (1 box) and Mandarin Duck Aix galericulata (1 box).

In total two hundred and twenty-four Barn Owls were ringed by Sussex Barn Owl Group, two hundred and twelve chicks and twelve adults. This was the first year the group embarked on colour ringing both adult and young Barn Owls with highly visible, unique rings with letters, this is to determine chick dispersal and adult movements, and it will be a long term meaningful project.

In August and September 4 sightings and 5 recoveries were reported to us.

A box in the upper Cuckmere contained a brood of 3 Barn Owls, 2 of which were considered to be of Dark breasted Tyto Alba guttata and Tyto Alba alba mixed parentage, although a license for DNA sampling was granted it was found the UK DNA database did not contain any guttata illustrations!

Note to all SOS members

Please be vigilant when observing Barn Owls in the field in East and West Sussex and report any colour ring sightings to info@sussexbarnowlgroup.org.

All sightings will be acknowledged.

Terry Hallahan

September 2024

Our group volunteers were treated to a rare occurrence recently, while visiting a box located in a barn at a site north of Brighton.

Inside we found four Kestrel chicks and three Barn Owl chicks co-existing in a box the size of a large tea chest!

The Kestrel chicks were approximately 22 days old, so these will fledge in five to ten days. The Barn Owl chicks were aged between 28 and 32 days and will remain in the box for a further 30 days.

All seven chicks were healthy in weight.

The Barn Owl which occurs in the UK is unmistakable with its ghostly white plumage. ‘Our’ race Tyto alba is separated into over 30 subspecies, the nearest of which is present in Central and Eastern Europe known as Tyto alba guttata, also described as the Dark Breasted Barn Owl. Very occasionally these birds wander to the UK and have been known to interbreed with our white owl.

This week we discovered a brood in a box located on private land close to the upper Cuckmere, which contained two female Dark Breasted chicks, which we believe to be from a guttata parent.

In the photos, note the comparison between Tyto alba and the chick we ringed here in Sussex

The British Trust for Ornithology has supported the Sussex Barn Owl Group’s colour ringing project and granted us the required endorsements.

We colour ringed a very early brood of two Barn Owls at a site near Cuckfield in late May. In the photo, we see red ring numbered ADA fitted to a 52-day old male. His sibling, another male, bears a ring with letters ADB. We will colour ring over 200 Barn Owls in Sussex during this breeding season.

We are now asking all observers to be vigilant and report any colour ringed Barn Owls to your normal recorder or database and also to the Sussex Barn Owl group, using our email below. Please state the ring letters, which, as you can see from the photograph, are highly visible, plus the location of your sighting. This will provide us with significantly more information about adult and chick dispersal. All sightings will be acknowledged, and observers will be informed of the bird’s original breeding location.

Out thanks go to Sussex Ornithological Society who are partnering this by funding the colour rings.

Please email us via: info@sussexbarnowlgroup.org

While the Barn Owl is the primary focus of the Sussex Barn Owl Group, we are also actively installing and monitoring Tawny Owl boxes. Despite being the UK’s most widespread owl species, Tawny Owls are now Amber listed due to a recent decline in numbers.

Pictured is an adult male, roosting in one of our mid-Sussex boxes, which we trapped and ringed on the 20th May.

Approximately 900 chicks and 100-150 adults are ringed in the UK annually. This isn’t a vast number, so we will be increasing our recording efforts to obtain further information regarding breeding site fidelity and brood size.

Tawny Owls are early breeders, so the team’s breeding monitoring activities start in April through to early June. We are currently checking around 50 boxes installed across Sussex. More box installations are also planned for 2024/25.

Barn Owl box monitoring and ringing starts late June and runs through to August, when we visit over 250 boxes!

Please contact the group if you are interested in participating by emailing: info@sussexbarnowlgroup.org.

Barn Owl monitoring in Sussex began in the middle of the last century through the efforts of the late Barrie Watson. 3,346 Barn Owls were marked using his rings. In 2019, our group was formed by Barrie, Terry Hallahan, and Stuart Card, and it is now home to a dedicated team of volunteers, including professional ecologists, ornithologists, biologists, and conservationists, as well as enthusiastic birders. Together we are committed to the preservation and protection of Sussex’s owl population.

• We monitor over 250 Barn Owl boxes across Sussex each year.
• Through our active installation of nest boxes in strategic locations, we have not only stabilised but also contributed to the growth of the Sussex Barn Owl population.
• With over 90% of Barn Owls in the UK now using nest boxes, our efforts have had a significant impact on their conservation.
• Beyond Barn Owls: While our focus is primarily on Barn Owls, we also install and monitor boxes for other bird species, including Tawny Owls, Little Owls, and Kestrels. Many of these boxes have been successfully occupied, resulting in the raising of broods, and furthering our conservation objectives.

Why not join us?

• Whether you’re a seasoned conservationist or simply passionate about the welfare of owls and birds of prey, we welcome you to join us!
• If you’re a resident of Sussex and share our commitment to conservation, we’d love to hear from you.
• If you own land with habitat suitable to support breeding raptors, or have seen owls in your local area, please get in touch.

Volunteer opportunities

Consider volunteering with us to help install and monitor nest boxes, contributing directly to the conservation efforts in your local community.
No experience is necessary – just a love for wildlife and a willingness to make a difference!

Join us today: Become part of our passionate team dedicated to the conservation of owls and birds of prey in Sussex.

Find out more here on Facebook or email us at: info@sussexbarnowlgroup.org