Breeding Season has finally kicked off here in @WythamWoods we had our first egg laid on the 2nd of April. The map here shows the progress of nest building as it was on the 1st of April. The Vast majority of boxes had no nest material inside (nest state = 0)

You can see in the plot here that nest building was just getting started prior to the Easter weekend, we still had 988 out 1209 nest boxes with no nesting material. Only 8 nests had been completed (nest state 4).

We had some really warm weather over Easter weekend and things really got going in relation to nest building we now had only 588 boxes with no nest material and 155 complete nests. A further 296 nests were in the process of being built

Despite the colder feel to the weather some of our birds started laying, out of the 155 complete nests there are 21 with eggs, 7 with 1 egg, 7 with 2 eggs, 5 with 3 eggs, 1 with 4, and 1 with 5 (our earliest eggs this year) and these are distributed quite evenly around the wood.

Stay tuned to this thread for more update throughout the 2021 breeding season

Here's a link to an interactive map where you can see what's happening in each nest box https://rpubs.com/mcmahok/Wytham_nest_states_0604
This is for nest building.

Time for another update from @WythamWoods. Last week things had gotten off to a slow start in terms of nest building, with only 155 complete nests. Well things have not really progressed. We've had some unseasonal weather lately with some snow yesterday.

In terms of nest building this gif shows how things have progressed since the 1st of April.

Here's a quick chart detailing the progress of nest building as of yesterday

Egg laying has been even slower to get cracking, last week we had 21 nests with eggs, now we are up to 81 nests with at least one egg, the majority of nests have only 1 or 2 eggs. Most have been laid over the last 2 days.

Here's the corresponding gif for egg laying. After yesterdays snow and todays sunny weather we would expect that egg laying will ramp up over the next week.

Here's a link to an interactive series of maps detailing everything that goes on inside our nest boxes, we will do our best to keep this as up to date as possible https://oxforduni.maps.arcgis.com/apps/MapSeries/index.html?appid=3804932748164a709b2b23cb35f4fafd#

Incubation has begun in four boxes over the weekend! With fieldworkers doing nest rounds this morning, we can expect to find plenty more eggs and potentially more females incubating. Check out our interactive map for daily updates on the birds progress. https://arcg.is/re4Cm 

Time for another update from @WythamWoods. Weather has improved dramatically in the last week and with that improvement has come increased activity from our tit population. We now have 566 complete nests (up from 273 on 13th of April)

Here's a gif of nest building progress since the 6th of April, the birds nesting in the centre of the woods are catching up on those on the edges. (incidentally nest stage 6 indicates a failed nesting attempt, we've had a nest with 4 eggs taken over by another pair)

Egg laying has really taken off in the last week too. This chart shows the distribution of first egg lay dates up until yesterday (there may be more who started to lay yesterday). There has been a steady increase in the number of pairs beginning to lay their clutches.

Here's how egg laying looks in gif form! Even though the pairs in the centre of the wood have caught up in terms of nest building, they are still a bit behind on egg laying.

We currently have 413 nests with at least one egg. Of these, 35 females have decided to start incubating.
These can be viewed here https://rpubs.com/mcmahok/758175 

For a more immersive map experience please do check out our online map where you can search through various nesting stages by date https://oxforduni.maps.arcgis.com/apps/MapSeries/index.html?appid=3804932748164a709b2b23cb35f4fafd#

Another week has passed, time for another update from @WythamWoods. We are up to 727 completed nests, with 275 of our 1209 boxes completely empty. So we've had 161 more nests completed in the last week.

You can see from the map below that most parts of the woods are now filled with nests.

Egg laying is underway all over the woods too. As of yesterday we had 4587 eggs laid by our tit population. That's approximately 7kg of eggs. Below is the corresponding map. There are still some areas where egg laying has been slow to catch up on the rest of the wood

Particularly in the eastern exposed areas of the woods, perhaps due to the biting easterly winds over the last few days

Despite the cold wind, lots of birds have started incubating. This series of maps shows only nest boxes which contain eggs. The most southerly end of Wytham (Bean Wood) is well ahead of the rest of the woods for incubating females, we even had our first chicks hatched there today

We are expecting lots of chicks over the coming week, but still plenty of eggs to be laid and incubated. Stay tuned for more updates,.