In a Wiltshire Garden, squirrels and jackdaws fought for weeks over possession of a nest box. Neither could have predicted their dispute would have a twist in the ending.

 

A dispute over ownership of a nesting box has led to growing tensions between a pair of jackdaws and some squatting squirrels. Both species staked a claim over the modest abode – a large plywood box that photographer Nick Upton fixed to a beech tree in his Wiltshire garden in 2020. Upton had hoped that the box would encourage tawny owls to move in – but a pair of jackdaws adopted the box instead, and raised three chicks in it during the spring of 2021. The jackdaws returned to nest again in 2022 – only to find that some squatters had moved in.

IN A FLAP

“I noticed the jackdaws seemed very wary and jumpy, and then I saw why,” says Upton. “A grey squirrel pair had taken to sleeping in the box every night, while the jackdaws roosted in the treetops. When the birds returned to the box every morning, the squirrels would spring to the entrance and chase the jackdaws. But the birds would only fly a few feet away before launching a counterattack, dive bombing the intruders. Then, as soon as the squirrels emerged to feed, the jackdaws would chase them mercilessly, trying to peck them as they scampered up the tree trunk.”

 

GOING NUTS

But the tufty rodents weren’t about to be pushed around so easily by a pair of featherweights. Both squirrels and jackdaws have quite dominant personalities, which makes them persistent. By spending long hours in a hide 70 feet away, Upton saw that the squirrels would come back when the jackdaws weren’t around, and the conflict would start up again as soon as the birds returned: “It’s been quite comical to watch the jackdaws jumping up and down on the lid of the box and pecking at it to disturb the squirrels.”

After constantly antagonising each other for over a month, the quarrel reached boiling point, with the squirrels and jackdaws engaging in full-blown territorial combat. It has long been known that grey squirrels will snack on bird eggs, but Upton says he can’t find any records of nest competition between grey squirrels and jackdaws. One study in Wales showed that jackdaws can evict the smaller red squirrel from nest boxes. But there are also records of grey squirrels booting tawny owls out of their nest holes. In other words, when squirrels and birds clash over nesting space, the conflict can go either way.

BEAK, TOOTH & CLAW

At one point, it appeared as though the jackdaws had emerged at the top of the pecking order. Upton says the birds  brought twigs and animal hair into the box, a tell-tale sign that nest-building has begun. However, the squirrels keep returning – and Upton says it was a close fight: “The stakes couldn’t have been higher. The jackdaw’s ability to lay and incubate eggs was entirely dependent on them booting out the competition!”

HOUSING CRISIS

Just when it appeared as though the jackdaws had gained the upper wing, a tawny owl discovered the nest box. On one occasion, the owl spent time inside when a squirrel was in residence. Upton’s trailcam footage showed the squirrel emerging unscathed – a lucky escape, given that tawny owls are known to occasionally predate on squirrels. Before long, the owl moved in one night, and resisted efforts from both the jackdaws and squirrels to reclaim the nest box. With all this competition over nesting space, Upton plans to invest in additional bird boxes, which he says are needed now more than ever: “Storm damaged trees, and the drive to cut down old ones deemed to pose a health and safety risk, takes away potential homes for tree-nesting birds. Clashes over nesting space may be fiercer than ever right now, so putting up bird boxes is a great way to help out jackdaws, owls, kestrels, and more.”

NESTING SUCCESS

Shortly after the first tawny owl (a male) showed interest in the box, Upton saw a female enter the box, He heard the birds calling to each other, with the male’s “ho-hoo” call answered by the female’s “kewick”. The birds paired up late in the spring, which is unusual but not unheard of. Upton says they grew increasingly noisy: “The female regularly called for food and the male sat around in the beech tree day and night, and alarm called if I or our cats got too close.”

While the female sat on her eggs, the male took on hunting duties, bringing 2-5 rodents to the nesting box each night. He also hunted during the day – tawny owl behaviour which is usually seen only when there are chicks in the nest.

Sure enough, one day in mid-June, Upton went outside to turn on his camera trap and saw a chick sitting in the entrance to the box. The single owlet fledged in late June, flying vertically up into the beech tree in response to its parent’s calls.

It was the first baby to be born in the box that year. The owls had succeeded where the jackdaws had failed.

 

Upton was surprised at how quickly the tawny owls reared their chick. Not only did they nest late in the season, but only 62 days elapsed from the moment the male took over the nestbox, to the day the chick fledged. The British Trust for Ornithology suggests incubation is usually 30 days, and fledging time 35-39 days. Upton speculates that the warmer temperatures so late in the spring may have led to faster development. He is unsure how many chicks were born but notes that “hatching is staggered so younger chicks are smaller and get fed less, and don’t survive if there is not enough food.” Upton believes that the single fledgling might point to the fact that the adults were a young pair, and hopes they will return next spring and start nesting earlier.

THE CONFLICT CONTINUES

While the owls were nesting, Upton saw a jackdaw pair mobbing the larger birds, and on several occasions the squirrels returned to peer inside the box, always backing off when they spotted an adult owl inside (one actually entered the box for a couple of minutes when the owlet was alone in the box. Fortunately, neither squirrel nor owl came to any harm).

As soon as the tawny owl chick had fledged, a pair of stock doves began peering into the vacated box (stock dove breeding season continues into the summer). Ultimately, they didn’t nest but the box continued to receive plenty of interest from all other parties, including squirrels, jackdaws and the tawny owls, who returned to begin their autumn courtship in September. Upton described hearing the “male singing beautifully with ululating hoots at dusk, with the female answering “kiwick” from nearby.” One morning, he witnessed jackdaws, magpies and jays all “going mad in the beech tree, alarm calling and swooping around near the box, with an owl at the entrance.” Now that breeding season is well over, the jackdaws and stock doves are less likely to do much nest prospecting. But the owls are around quite often and Upton thinks they still view the tree as part of their territory. He expects them to try to reclaim the box next year, likely earlier this time as tawny owls usually start laying in February. In the meantime, the squirrels have continued to check out the box regularly and may seek to nest in there during the colder months. But if it’s a contest between the squirrels and the owls taking up residence, Upton is backing the birds to take charge…