Jørgen Søraker

Fledgling distributors
Great tit 323
Blue tit 134
Pied flycatcher 96
Coal tit 40
Nuthatch 11
Marsh tit 2

Mean fledgling number for great tits this year was 4.6, which is a bit lower than last year (~5)

Pied flycatchers produced about the same number of fledglings as last year, on average (4.4)

19.07.2025 20:31 — 👍 3    🔁 0    💬 0    📌 0

Last fledge check of the season home in Norway today. Very low production this year, with most of the early broods failing. However, rather high density, with eggs in 137/186 boxes. Distribution:
Great tit 76
Blue tit 24
Pied flycatcher 27 (record high)
Coal tit 7
Nuthatch 2
Marsh tit 1

19.07.2025 20:31 — 👍 7    🔁 1    💬 1    📌 0

Fledgling distributors
Great tit 323
Blue tit 134
Pied flycatcher 96
Coal tit 40
Nuthatch 11
Marsh tit 2

Mean fledgling number for great tits this year was 4.6, which is a bit lower than last year (~5)

Pied flycatchers produced about the same number of fledglings as last year, on average (4.4)

19.07.2025 20:29 — 👍 1    🔁 0    💬 0    📌 0

Well done @roriwijnhorst.bsky.social and congratulations to both of you!🥳

18.07.2025 20:33 — 👍 1    🔁 0    💬 0    📌 0

Congratulations Denise!

18.06.2025 15:30 — 👍 1    🔁 0    💬 0    📌 0

Field team in Wytham Woods May 2025

Image of the new Biology Building, completed, and opening from August 2025

Lunch with the field team to celebrate another successful season - May 2025

Interested in Postdoc Research here in Oxford? Many projects possible using long-term population studies of birds, field & lab experiments with insect consumers, phenology of trees all in Wytham woods & based in new Biology building
marie-sklodowska-curie-actions.ec.europa.eu/calls/msca-p...

16.06.2025 09:01 — 👍 49    🔁 36    💬 0    📌 1

Map showing the tracks (yellow lights) followed to check my set of boxes (red dots) in Wytham Woods

Now that the field season is coming to an end (first day off since late April, I decided to compile some stats of what I have done during the last month.

To check the 208 (reduced a bit in mid-May), I have walked a total of 446km with an accumulated elevation gain of 9431m!

26.05.2025 11:04 — 👍 17    🔁 3    💬 1    📌 1

Indeed!

13.05.2025 08:26 — 👍 1    🔁 0    💬 1    📌 0

It’s like poetry!

30.04.2025 15:25 — 👍 1    🔁 0    💬 0    📌 0

Assessing the 'Small Population' Paradigm: The Effects of Stochasticity on Evolutionary Change and Population Growth in a Bird Metapopulation Habitat loss is resulting in smaller and more fragmented populations, increasing their susceptibility to stochasticity. We examined the effects of stochasticity on population growth and body mass ove...

New paper out🚨 Yimen Araya-Ajoy led this investigation on the impact of environmental and demographic stochasticity on (fluctuations in) growth rates in house sparrows. Also show how evolutionary change in body mass is driven more by drift than selection!

onlinelibrary.wiley.com/doi/full/10....

04.04.2025 15:45 — 👍 2    🔁 2    💬 0    📌 0

A single Blue Tit egg in a complete nest inside a woodcrete nestbox in Wytham Woods, 3 April 2025

Early developing Oak in Wytham Woods, Oxfordshire, April 2025

Newly emerged Oak leaves, Wytham Woods, near Oxford, 3 April 2025

Figures showing the change in the date of the first egg in the Great Tit and Blue Tit populations at Wytham Woods, near Oxford 1960-2025, and the relationship between average March daily maximum temperature and date of the first egg in the population for each species. In each figure the line fitted is for the data for the 65 years from 1960-2024, with the value for 2025 shown as a green (Great Tit) or blue (Blue Tit) star. The two right hand panels compare the change over time and the response to March temperature in the two species; Great Tits show a slightly steeper response to temperature than Blue Tits, and are advancing the population first egg date slightly more quickly.

The first eggs have been laid in this, the 79th year of data collection in the Wytham Tit Project! First Blue Tit egg laid 2 April, first Great Tit 3 April. Looks like an early spring, with first oak leaves out, though the observed first egg dates fit the long-term pattern well
wythamtits.com#intro

03.04.2025 21:11 — 👍 41    🔁 8    💬 0    📌 2

The first great tit (and blue tit) egg in my round for the season! Marley Plantation early as always🥚

03.04.2025 12:39 — 👍 3    🔁 0    💬 0    📌 0

Todays nest-box round revealed some nests close to completion. Not many had started building tho. Yet! Also produced a less fancy Strava-map than @davididiaquez.bsky.social, but still looks cool from above!

25.03.2025 22:25 — 👍 6    🔁 0    💬 0    📌 0

A chilling little owl

Wonderful last couple of days at @portlandbirdobs.bsky.social! Med gulls, sandwich terns, black redstart, purple sandpipers, little owls, avocets, ring ouzels, lots of newly arrived migrants and more! All this in wonderful EGI company

21.03.2025 16:10 — 👍 5    🔁 0    💬 0    📌 0

Delighted to be hosting Prof Andy Dobson @andy2dobson.bsky.social for an EGI Seminar next week (Fri 14 March) on "The Eye of the Finch: Ecology and Evolution of an Emerging Avian Pathogen" All welcome at 3.30pm, Seminar Room in @biology.ox.ac.uk Mansfield Road

04.03.2025 17:25 — 👍 19    🔁 8    💬 1    📌 1