The Ryobi Pro Nestbox Vacuum.

I’m going to let the cat out of the bag - I can use a hoover. There I’ve said it, I’ve survived so long kidding my wife that I have no idea how to hoover the house.

Then I had a brain wave!

I do occasionally have them - brain waves that is and this one as it happens worked pretty well. I monitor a group of tawny owl boxes as part of a study alongside the University of Chester and recently we decided to start taking a closer look at prey remains from the nest boxes that have been active over the last couple of seasons. Tawny owls are cavity nesters for the most part (They will use old nests of other birds as well) so nest boxes are often a good way of supporting owls and monitoring them when they use the boxes. Owls don’t build their nests, and in the case of the tawny owl they will find a cavity and lay their eggs on the rotting detritus/wood pulp within that cavity, within a nest box this might be broken down pellets.

Once inside the cavity, 3-4 eggs are laid and depending on prey availability this will dictate how many owlets manage to branch. Yes, that’s right, you sharp-eyed reader, tawny owl chicks will branch well before they can naturally fledge (intransitive. Of a young bird: To acquire feathers large enough for flight; to become fully plumed. Also, figurative.) Tawny owl chicks at around the age of 14-21 days old will begin to climb out of their nest cavity and into the surrounding trees well before they can fly, they are however fantastic climbers and will sit silently nearby waiting for nightfall when their parents will come back to their squeaky calls and feed them - this is known as branching. There is however a window of 2-3 weeks where the nest box will have food dropped in for the chicks, the chicks will poo and regurgitate fur and bones of said prey species into the box and for biologists this can make for interesting science.

Tawny owl chicks and prey in one of the nest boxes. Copyright J Hill. 

This time of year, the owlets are fully fledged and finding their way in the big wild world (or Hogwarts, who knows?). It’s the perfect time to go around the next boxes and remove the nest box detritus so some lucky university students can pick their way through and try to identify prey species. How I hear you scream; do we get the nest box material out without spilling it all over the forest floor?

Enter light bulb moment and the Ryobi PRO Nest Box Vac! Yes - honestly, I bought a Ryobi portable hoover, and it works an absolute dream for hoovering out the contents of a tawny owl nest box. Granted, it doesn’t like twigs and it’s not the easiest thing to hold whilst up a ladder, but it sucks rodent skulls up really well. I am not sure the lady who walked past walking her dog knew what to say - I’ve not had a knock on the door from the police yet.

As if that wasn’t clever enough for you, we also took three core samples of each box with the idea of testing it using eDNA technology. I’m not about to try and explain how this works other than someone much more intelligent than me in genetics might be able to extract the DNA of prey species from within the detritus samples gathered. If it works, I honestly think it will be a game changer for prey analysis in predatory bird nest boxes.