Tag Archives: nest boxes

Sunday 19th January 2025: surveying and cleaning nest boxes – discoveries and insights

A very, very chilly morning, but ten of us gathered at 9.45 am for the first morning of our annual nest box survey and cleaning session.

The morning

We took our usual route – along Crag Lane, taking the diagonal path into the plantation, cleaning all the nest boxes around the plantation and then heading south back to Crag Lane, and finishing at lunch time with box 53.

As in every previous survey, we found that most of the tit boxes had been used for nesting. The robin boxes had not been used by robins but one had been used by a family of great tits or blue tits – we can tell by the nesting material.

Friends of Adel Woods surveying and cleaning nest boxes on 19th January 2025

Blue tits and great tits both build their nests out of moss, grass, fur, feathers and man made materials – it is common to find in their nests orange, green or white material which seems to come from tennis balls!

As usual we found that the nest boxes were homes not only to tits but also to assorted insects – clothes moth larvae, and woodlice – and spiders.

Friends of Adel Woods cleaning nest boxes. A hibernating comma butterfly in Adelj Woods
A hibernating comma butterfly in Adel Woods

We also had a new discovery. As your correspondent lifted one of the nest boxes down from the tree, he saw a leaf stuck to the bottom of it. Fortunately, he did not brush the leaf off the box because the leaf opened up to show a flash of orange and turned out to be a hibernating comma butterfly! The photograph above shows how well the butterfly was camouflaged as a leaf, and the photograph below shows its open wings. Fortunately, the butterfly returned to its state of hibernation and we were able to clean the nest box and replace it on the tree with the butterfly still in place.

The comma butterfly gets its name from the white “comma” shape on the underwing – which can be clearly seen in the photograph above.

A hibernating comma butterfly in Adel Woods
The same hibernating butterfly, sleepily opening its wings

The caterpillar stage of the comma is spectacular as can be seen in the photograph below. We came across this one back in August 2013 during a FOAW task. The white stripe along its back makes it look like a bird dropping.

The caterpillar stage of a comma butterfly photographed in Adel Woods by Friends of Adel Woods in August 2013
A caterpillar stage of a comma butterfly (polgonia c-album) photographed by Steve Joul on 13th 
August 2013

After surveying and cleaning box 53, we took a lunch break from about 1.30 to 2.30 pm.

The afternoon session

Refreshed after lunch, we continued cleaning and surveying the nest boxes along Crag Lane to the picnic area and Adel Crag, and then made our way down the Meanwood Valley Trail, finishing at about 4.45 pm.

Blue tits lay typically eight to twelve eggs, but sometimes as many as sixteen, one per day! Great tits are larger than blue tits, but lay a clutch of seven to nine eggs. The eggs of both species are similar – creamy white with brown spots – but the great tit eggs are larger.

a tit nest in Adel Woods: Friends of Adel Woods
A tit nest in Adel Woods photographed in the afternoon. Note the moss, grass and grey manmade material

It is common to find one or two unhatched eggs in the nesting material which probably indicates that most of the eggs hatched and the chicks successfully fledged. Sometimes though, as in the photo above, we may find more, which may indicate that the female was predated before laying all her eggs. Sometimes we find skeletons in the nest, indicating that the parents were predated whilst raising their young.

Having made our way down the Meanwood Valley Trail almost as far as the pond, we decided to call it a day in the fading light.

About Friends of Adel Woods

We hope that you have enjoyed reading about our activities and would be delighted if you would like to join us.

Friends of Adel Woods were formed in 2009 to help maintain Adel Woods and encourage people to enjoy them. We meet one weekend morning a month to carry out various jobs or ”work parties”, and we also put on educational events such as bat walks, fungal forays and birdsong walks.

We are a very friendly group and welcome new members who want to help preserve our special woods, enjoy fresh air and exercise in the woods, and make new friends. If you would like to take part in our activities, keep an eye on our Home Page and just come along to one of our work parties.

If you would like to join our email mailing list, please get in touch by leaving a comment on this website – you should be able to see a comment button at the bottom of this page.

Friday, 2nd February 2024: putting up two new nest boxes

Friends of Adel Woods putting up a tit box on the Meanwood Valley Trail
Putting up a nest box for blue tits on the Meanwood Valley Trail

When we surveyed the FOAW nest boxes on the 13th and 14th January, we found that three needed replacing, but only had one spare nest box to put up in their place. The committee therefore agreed to purchase two Schwegler tit boxes from Ark Wildlife. We purchased one with a 32 mm hole which is suitable for blue tits, great tits and nuthatches, and one with a smaller 26mm hole which is suitable just for blue tits.

They arrived yesterday and Steve Joul and your correspondent put them up this morning. We already have one Schwegler nest box near Old Leo’s clubhouse and we have been very impressed with it. It was donated to us in 2010 by our member Tina and it is very well designed and as good as new.

Friends of Adel Woods: a nest box on the Meanwood Valley Trail
The blue tit box on an oak tree by the Meanwood Valley Trail

This morning we put up the first nest box on the Meanwood Valley Trail about 100 metres north of the Seven Arches aqueduct. While there, we took the opportunity to have a look to see how the Seven Arches looks following work carried out by its owner, Yorkshire Water, to remove trees and brambles growing on the structure. A few weeks earlier, our local ranger, David Preston, and the Meanwood Valley Volunteer rangers had cleared scrub from the Scotland Wood side.

Friends of Adel Woods and the Seven Arches and the Meanwood Valley Trail
The Seven Arches photographed from the Scotland Wood side and looking good!

We put up the second nest box on the Meanwood Valley Trail just north of Adel Pond.

Friends of Adel Woods putting up a tit box on the Meanwood Valley Trail
Putting up a tit box on the Meanwood Valley Trail north of Adel Pond

The Schwegler nest boxes are made of a mixture of woodchips, concrete and clay and are long-lasting- expected to last for up to 25 years. We are looking forward to see how our new nest boxes have fared when we survey and clean them next January.

Friends of Adel Woods: snowdrops
Snowdrops by the side of Buckstone Road

On the way home afterwards it was a pleasure to see the snowdrops by the stream running alongside Buckstone Road.

About Friends of Adel Woods

Friends of Adel Woods were formed in 2009 to help maintain Adel Woods and encourage people to enjoy them. We meet one morning a month to carry out various ”work parties”, and we also put on educational events.  We are a very friendly group and welcome new members who want to help preserve our special woods, enjoy fresh air and exercise in the woods and make new friends. Please get in touch by leaving a comment on this website if you would like to take part in our activities.

13th January 2024: day one of the FOAW annual nest box clean and survey

Friends of Adel woods surveying nest boxes
Ready for action!

A fine but cold day for day one of our annual survey and clean of our nest boxes in Adel Woods. At 10 am we had an amazing turnout of nine people - and later on twelve when three more people joined us in the woods!

We have thirty eight tit boxes and four robin boxes in Adel Woods, so we had our work cut out! Tit boxes are the familiar nest boxes with a round hole in the front. Robins will not use tit boxes and prefer a box with a large opening at the front (as shown below) placed near the ground – or not to use a nest box at all. 

We need to clean the nest boxes because tits and robins do not re-use nests from previous years. In 2021 we were unable to clean out the nest boxes due to the covid lockdown and when we surveyed the nest boxes in January 2022 we found that in Spring 2021 nests had been built on top of the previous year’s nests. This probably happens all the time in natural nesting holes, but it is not a good start for young chicks because the old nesting material is frequently full of fleas and mites, and sometimes is very wet.

Friends of Adel Woods; robin nest box
A robin box made by Friends of Adel Woods – note the large entrance.

Our morning’s work

We set off down Crag Lane and then up the “diagonal” path on the right hand side of Crag Lane, just before Old Leo’s car park. We paused at the entrance to the path to have a look at some Yellow Brain fungus (see yesterday’s blog post) and then started work cleaning our first nest box, number 17.

FOAW’s tit boxes have three different sizes of entrance hole. The two larger sizes, 28mm or 32mm, allow access to blue tits, great tits or nuthatches. The smallest entrance hole, 25mm, permits access only for blue tits. Coal tits may use nest boxes, but prefer a nest box only a metre or so above the ground so they do not use our tit boxes which are all at least three metres from the ground.

Nest box 17 seemed to contain two typical tit nests made of moss and grass – a great tit nest containing two unhatched eggs, and, on top of it, a blue tit nest containing one unhatched egg. Blue tit and great tit eggs look very similar, but great tit eggs are slightly bigger (17.5mm x 13.5mm) than blue tit eggs (15.6mm x 12mm).

Friends of Adel Woods repairing a nest box in Adel Woods on 13th January 2024
Replacing the damp proofing on box number 17

We have covered all our wooden tit boxes with damp proofing plastic to keep them dry. This has been very successful over the years, but the plastic gets holes where pecked by the birds and this year we had to replace or patch up many of the nest boxes.

Friends of Adel Woods: surveying nest boxes in Adel Woods. Tit nest.
A typical tit nest made of moss, feathers and grass found in box 18

This morning we surveyed eleven tit boxes and two robin boxes. Ten tit boxes had nests inside them, and one a partly built tit nest. Some had one or two unhatched eggs concealed in the nesting material but since great tits lay seven to nine eggs and blue tits eight to twelve eggs, we infer that most of the nests were successful even though some eggs did not hatch. One nest contained the skeleton of a fully formed bird – probably a chick, but perhaps an adult. One contained a sweet chestnut shell, indicating that after the tits departed a wood mouse moved in for a while.

Turning to the robin boxes, one contained lots of leaves and had clearly been used by a squirrel for roosting, while the other contained a partly formed tit nest.

Friends of Adel Woods: a blackbird nest  at the base of a tree in Adel Woods
A blackbird nest at the base of a downey birch

One of the most exciting finds was made by Steve Joul when he found a blackbird nest near the ground at the back of the tree on which nest box number 8 was hanging.

Friends of Adel Woods nest box survey on 13th January 2024
No report on our nest box surveys is complete without a photo of Steve climbing a ladder!
Friends of Adel Woods: rotten nest box material full of larvae and maggots
Nest box material well and truly processed by insects and containing larvae or maggots
Friends of Adel Woods surveying nest boxes in Adel Woods on 13th January 2024
Viewing “Tina’s nest box” – a posh Schwegler box near Old Leo’s clubhouse

We continued working till about 1.20pm when we adjourned for lunch and a piece of Christmas cake. We had surveyed the nest boxes in Alwoodley Plantation, the boxes on the path running north adjacent to the disused rugby pitch, and the nest boxes on Crag Lane behind the rugby clubhouse.

Our afternoon session

Five of us resumed work at about 2.30pm and surveyed the nest boxes along Crag Lane from the rugby club to the picnic area, and then started to make our way down the Meanwood Valley Trail. surveying and cleaning nine nest boxes – eight tit boxes and one robin box.

The robin box contained a tit nest and leaves on top of it suggesting that a squirrel had used it for roosting. Of the tit boxes, seven contained a nest, and one contained moss which looked very fresh suggested that it may have been put there this year, even though it would be early for tits to start nesting.

Friends of Adel Woods surveying nest boxes in Adel Woods: nesting material containing orange man-made fibres.
A tit nest made in part with man-made fibres – probably from tennis balls

One of the striking features which we always find in tit nests is the use of man-made materials – probably the covering of green, yellow or orange tennis balls – to make the nest.

Friends of Adel Woods: witches butter fungus and hairy curtain crust fungus in Adel Woods on 13th January 2024
Black “witches butter” fungus and hairy curtain crust fungus on a tree stump

A propos of nothing we found these excellent examples of fungi this afternoon.

Friends of Adel Woods: surveying nest boxes  in Adel Woods on the 13th January 2024
Time for a cup of tea!

We finished work at 4.35 as it was getting too dark to see.

In summary, during today’s survey we found that all the tit boxes were used. The nesting material in some tit boxes was dry, but in some it was very wet indeed – perhaps not surprising in view of the recent months of seemingly relentless heavy rain. Fortunately, today we spruced up twenty one nest boxes for this year’s broods.

Several of the nests contained droppings, indicating that the nest box had been used for roosting, as nesting birds do not defecate in the nest and clean out droppings from chicks.

Thank you to everyone who helped with today’s workparty!

To read more, have a look at tomorrow’s blog entry for day two of our annual nest box survey and clean.

Friends of Adel Woods were formed in 2009 to help maintain Adel Woods and encourage people to enjoy them. We meet one morning a month to carry out various jobs, and we also put on educational events.  We are a very friendly group and welcome new members who want to make new friends and enjoy getting out in the woods.

Sunday, 23rd January 2022: surveying nest boxes, part 2

Today we completed our survey of the nest boxes in Adel Woods. We started the survey on Sunday the 9th, when we surveyed about two thirds of the boxes. (You can find out what we discovered that day by clicking here.)

This morning we met at 10 am at the Slabbering Baby entrance to Adel Woods at 9.55 am. Steve Joul drove his landrover down to the Slabbering Baby and we set off up the Meanwood Valley Trail, past the pond, to nest box 35, which was the next nest box to be cleaned when we finished on the 9th. It was a pleasant morning and there were five of us, including Steve.

Having cleaned nest box 35 we made our way down the Meanwood Valley Trail to the Seven Arches, cleaning another fourteen nest boxes, finishing with box 39, to the right of the path. We then put up nearby two more nest boxes donated by Rob and Tina, having numbered them 50 and 51.

What we discovered

Like many of the nest boxes we surveyed on the 9th, most nest boxes contained two nests – one from Spring 2020, and another on top of it from Spring 2021. This was because we were unable to clean and survey the boxes in January 2021 due to Covid 19.

People are often surprised that great tits and blue tits don’t simply re-use an existing nest, but they don’t even though it clearly takes a huge amount of time and hundreds of trips to make a tit nest from moss and grass. No doubt there is an evolutionary advantage to raising chicks in a new nest as the old nests are often full of fleas and mites which would harm the young brood.

Friends of Adel Woods: nest box on the Meanwood Valley Trail
The remains of a tit nest from 2020 judging by its condition. Note the many grubs, and that the nesting material is largely reduced to dust.

Nest box 35, the first we surveyed, also contained 7 unhatched eggs, so the likelihood is that in Spring 2021 the nest was wholly unsuccessful.

We found two nest boxes which had been used by nuthatches. You can always tell a nest box has been used by nuthatches before opening them because nuthatches fill all of the gaps in the nest box, particularly around the lid, with mud. The nest inside is totally different from a tit nest in that it is made of bark chips and looks like a bowl of bran flakes!

We were amazed to find in one nest box a hibernating noctule bat. Needless to say we immediately closed the nest box and put it back up without cleaning it. Perhaps we shouldn’t have been surprised because we found a hibernating noctule bat in the same nest box in January 2020, so it was probably the same individual. What was interesting was that the nest box had also been used by nuthatches to bring up a family in Spring 2020 or 2021 – so it was a bit like a timeshare!

Noctule bats are the UK’s largest bat and you can find out more about them on the Woodland Trust’s website here.

We have one particularly large nest box which is about 45cm deep which is supposed to be for treecreepers or starlings. We have never had treecreepers or starlings in it, though we have found tit nests in it in the past – which makes you wonder about young fledglings having to fly up to the exit hole to leave the nest! In 2020 we found a tit nest and a mummified squirrel in the box. This year we found about 30 cm of dried leaves in the box, so it had clearly been used for nesting by a squirrel.


Several nest boxes contained bird droppings on top of the nesting material, indicating that they had been used for roosting since the last breeding season. Several contained moth larvae which chew the wood of the nest box and create a very tough spongy material in which they pupate. It also tends to glue the lid of the nest box shut!

So that is it for another year. When walking through Adel Woods this Spring, keep an eye out for our nest boxes and take a few minutes to watch from a distance and see who is using them. Pretty well all of the nest boxes you see will be used.

Sunday, 9th January 2022: surveying and cleaning the nest boxes in Adel Woods

Surveying nest boxes in Adel Woods on 9 January 2022
Retrieving nest box number 5, near Devil’s Rock, Alwoodley Plantation

It is 12 years since the Friends of Adel Woods made and put up our first nest boxes in Adel Woods under the tutelage of Steve Joul, senior ranger with Leeds City Council. Since then we have surveyed them every year – except for last year when we were in a Covid 19 lockdown. This year, your correspondent was intrigued to find out how our feathered friends have fared without their annual spring clean in January 2021.

Most of the nestboxes are the tit boxes which you can see high up in trees throughout the woods. However, we also put a number of robin boxes out of sight within thick holly bushes – not a pleasure to survey! Robin boxes differ from tit boxes in that robins like to nest in a box with a large open front. This means that they have to be placed somewhere hard to find, to keep them safe from predators like magpies, woodpeckers and squirrels.

It was rather “parky” as we met in Old Leo’s carpark at 10 am, but fortunately the weather warmed up surprisingly quickly and we had a very enjoyable and successful day. In the morning there were eight of us including Steve.

We followed our usual route, heading along Crag Lane towards King Lane and taking the first turn left into Alwoodley Plantation where we surveyed our first boxes. We then made our way through the plantation, turning left at the practice rugby ground to come back to Crag Lane. We then continued along Crag Lane to the picnic area surveying nest boxes along the way.

By then it was lunchtime and we broke off for lunch after returning along Crag Lane and cleaning and surveying “Tina’s nest box”, a woodcrete nest box near the entrance to Old Leo’s car park.

Friends of Adel Woods surveying Tina's nestbox near Old Leo's carpark in Adel Woods
Surveying Tina’s nestbox near the entrance to Old Leo’s carpark

After an enjoyable lunch break, five of us resumed our survey, making our way down the Meanwood Valley Trail from the picnic area towards Adel Pond. We finished as dusk fell at about 4.20 pm.

Friends of Adel Woods: Nestbox survey on 9th January 2022

So what did we discover?

In all, we surveyed twenty two nestboxes today. Most of the tit boxes had been used. Of the three robin nest boxes we surveyed, only one had been used for nesting – by a pair of great or blue tits!

Blue tits and great tits nest once a year and do not re-use old nests and so, as expected, we found that most of the nestboxes contained two nests, one (from Spring 2021) on top of an earlier one from 2020.

We were surprised to find that most of the lower nests from 2020 had been “processed”, presumably by insects, almost to a kind of dust. The photograph below shows the difference between the condition of the earlier nest (on the right) and last year’s nest (on the left).

Two nests in a single nestbox – the one on the left from 2021 built on top of the one on the right from 2020

As is usual a number of the nestboxes contained one or two unhatched eggs – as in the photograph above. The nest on the left also contained a number of droppings, indicating that the nest box has been used for roosting by adult birds since the breeding season.

One of the things which we find each year is that tits like to use coloured man-made fibre in building their nests. In the photograph above, we can see blue, green and white fibre, but we also found plenty of bright orange fibre in other nests. We speculate that these fibres must have been collected from lost tennis balls, or possibly discarded clothing – though we have never found that number of tennis balls, or much clothing with those colours!

Usually we find one or two nuthatch nests, but none of the nestboxes surveyed today had been used by nuthatches in 2020 or 2021. Nuthatch nests are very different from tit nests as they are made from bark chips – looking rather like a bowl of bran flakes – rather than moss and grass. And it is usually possible to tell from the outside that a box has been used by nuthatches because they seal up any gaps between the lid and the box or in the sides of the box with mud.

There were two sad finds, reminding us that life in the wild can be harsh. One nest box contained twelve unhatched eggs. Another contained the skeletons of eight well developed chicks. Presumably, in each case the adult tits had fallen prey to a sparrowhawk or suffered some other sad fate.

We are completing our survey on Sunday the 23rd January. See our website for details! In the meantime, here are some photos of today’s activities.