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Breaking: September 2025 was record-warm in Finnish Lapland, for the third time in a row.

Monthly mean temperature in Sodankylä Tähtelä was 11.0 °C, exceeding the previous record of 10.3 °C set in 2024 (which itself had exceeded the previous record of 10.0 °C set in 2023 and 1934).

Time series of September monthly mean temperatures in Sodankylä Tähtelä in 1901–2025.

Reposted by Juha Pöyry

Tagfalter-Monitoring Deutschland @faltermonitoring.bsky.social · 14d

We are happy to share this on a political level very important paper from our team - The Grassland Butterfly Index for Germany. Especially for the last ten years the results show a negativ trend for grassland butterflies in Germany doi.org/10.3897/natu... @pensoft.net @ufz.de #NRR

Development of the German Grassland Butterfly Index 2006-2023, based on German Butterfly Monitoring Scheme data. The annual index values (points) and the smoothed trend with 95% confidence intervals are shown

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Reposted by Juha Pöyry

Rothamsted Research @rothamsted.bsky.social · 16d

📣New Study: Collapse in UK insect populations may be overstated, but local communities are being reshaped by CC & development 🐝🪲🦋🦗🪰🐞@btobirds.bsky.social @uor-research.bsky.social @savebutterflies.bsky.social @ukceh.bsky.social @universityofleeds.bsky.social www.rothamsted.ac.uk/news/insects...

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Juha Pöyry @poyryjuha.bsky.social · 22d

This sp. is a climate opportunist that is expanding towards the north. It has also obtained a strong foothold in S Finland in recent years.

Reposted by Juha Pöyry

Prof. Stefan Rahmstorf @rahmstorf.bsky.social · 27d

Grundwissen Klima zur Erinnerung: weniger Tempo beim Klimaschutz heißt unerreichbare Klimaziele! Denn ein großer Teil des CO2 bleibt Jahrtausende in der Luft. Die *kumulativen* Emissionen bestimmen Ausmaß der Erderwärmung! Tempo ist entscheidend!

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Reposted by Juha Pöyry

Suomen ympäristökeskus - Finnish Environment Institute (Syke) @syke.fi · 26d

Suomen luontotyyppien ja lajien tila heikkenee edelleen. Tämä käy ilmi Suomen raporteista Euroopan komissiolle luonto- ja lintudirektiivien toimeenpanosta.

Kehityssuunnan kääntäminen vaatii lisäpanostuksia luonnonsuojeluun, ennallistamiseen ja seurantatyöhön.

www.sttinfo.fi/tiedote/7143...

Luontotyyppien ja lajien tilan heikkeneminen jatkuu – Suunta voidaan kääntää investoimalla ennallistamiseen | Suomen ympäristökeskus

Suomi raportoi Euroopan komissiolle luonto- ja lintudirektiivien toimeenpanosta. Arvioinnin tulokset (ym.fi) osoittavat lajien ja luontotyyppien heikkenevän kehityksen jatkuvan edelleen. Myös ennallistamisasetuksen toimeenpanoon tarvitaan yhä enemmän panostuksia lajien ja luontotyyppien tilan parantamiseen sekä seurantaan.

www.sttinfo.fi

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Reposted by Juha Pöyry

Richard Fox @richardfoxbc.bsky.social · Sep 3

📣 New research, including @savebutterflies.bsky.social #citizenscience data, shows winners & losers across >1200 insect species in Britain since 1990. Urbanisation identified as major driver of decline for moths, ladybirds & hoverflies www.nature.com/articles/s41... 🌍 🦋🐞🦗🪲🐝

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Reposted by Juha Pöyry

Mika Rantanen @mikarantane.bsky.social · Sep 1

Summer 2025 in Sodankylä, Finland was the coolest summer of the 2020s, but still ~0.5 °C warmer than the most recent 30-year period (1996–2025).

Modern summers in northern Fennoscandia are warmer than those in medieval times: www.nature.com/articles/s41... & www.nature.com/articles/s41...

Jun-Aug mean temperature in Sodankylä, Finland in 1901–2025.

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Juha Pöyry @poyryjuha.bsky.social · Sep 1

Helmi-ohjelma on parantanut luonnon tilaa Suomessa, mutta rahoitusleikkaukset uhkaavat vesittää hyvän kehityksen.

www.syke.fi/fi/tietoa-me...

Helmi-ohjelma on parantanut luonnon tilaa – resurssipula haastaa tavoitteet

Suomen luonnon monimuotoisuuden turvaamiseksi tehtiin Helmi-elinympäristöohjelmassa jälleen merkittäviä toimia koko Suomessa vuonna 2024. Suomen ympäristökeskuksen kokoama ohjelman vuosikatsaus 2024 k...

www.syke.fi

Reposted by Juha Pöyry

Ilmatieteen laitos - Finnish Meteorological Institute @ilmatieteenlaitos.fi · Aug 27

Ilmastonmuutos vaikuttaa vahvasti perhosiin. Ilmaston lämmetessä Suomeen on levinnyt etelästä monia uusia perhoslajeja. Toisaalta pohjoisten metsien, soiden ja tunturien lajeilta uhkaa loppua elintila.

www.ilmatieteenlaitos.fi/artikkeli/3l...

Lämpenevä ilmasto muuttaa perhoslajistoamme - Ilmatieteen laitos

Ilmaston lämmetessä maahamme on levinnyt etelästä monia uusia perhoslajeja. Kasvukauden pidentyessä yhä useampi perhoslaji myös tuottaa kesän aikana enemmän kuin yhden sukupolven. Toisaalta

www.ilmatieteenlaitos.fi

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Reposted by Juha Pöyry

Prof. Stefan Rahmstorf @rahmstorf.bsky.social · Aug 28

I was shocked when I first saw these results from standard climate models used in IPCC reports: for high emissions, the Atlantic overturning circulation #AMOC shuts down in all 9 models that ran past 2100, and is well on the way to shutdown by 2100.
Our paper on that is out today.🧵

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Juha Pöyry @poyryjuha.bsky.social · Aug 22

@mahtabyazdanian.bsky.social defending her PhD thesis "Moth abundance changes and consequent bottom-up effects on birds in boreal forests" today.

Congratulations for a really nice piece of work!

Tuomas Kankaanpää @bugwebs.bsky.social · Aug 22

@mahtabyazdanian.bsky.social defending her thesis on "Moth abundance changes and consequent bottom-up effects on birds in boreal forests". I'm proud to have mentored such a bright new PhD.

Three people, formally dressed in black sitting in a large lecture hall: Anu Valtonen, the opponent on the left, Sami Kivelä as the custos in the middle and Mahtab Yazdanian, the candidate in the speaker booth on the right.

Reposted by Juha Pöyry

UK Centre for Ecology & Hydrology (UKCEH) @ukceh.bsky.social · Aug 21

🦋 New UKCEH research with @naturalengland.bsky.social and @btobirds.bsky.social shows the positive impacts of agri-environment schemes (AES) on butterflies.

Paper: besjournals.onlinelibrary.wiley.com/doi/10.1111/... @jappliedecology.bsky.social

🧵🧪 1/

Positive impacts of agri‐environment schemes on butterflies from multiple evidence sources

Our results provide support for positive effects of AES on butterflies in England from multiple sources of evidence, providing confidence that these schemes are providing tangible benefits for butter...

besjournals.onlinelibrary.wiley.com

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Reposted by Juha Pöyry

Maija Karala @maijakarala.bsky.social · Aug 20

New summer adventures mean new moths! Here are a few I have met, photographed and illustrated this summer.

I’m at around 55 species of the 300 or so geometer moths found in Finland. At least I’m not running out anytime soon.

Digital illustration of a golden brown and yellow patterned geometer moth, Hydrelia flammeolaria.

Digital illustration of a blue-green geometer moth, Jodis putata.

Digital illustration of a black and white patterned geometer moth, Rheumaptera hastata.

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Juha Pöyry @poyryjuha.bsky.social · Aug 18

In 1990s, the species started expanding towards N-NW, and now it occurs commonly up to the Arctic circle. In 2025 the species was photographed on the Jehkats fell situated in the NW tip of Finland, adjacent to Norwegian border. 2/2
(Maps from FinBIF hub, Laji.fi)

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Juha Pöyry @poyryjuha.bsky.social · Aug 18

The Silver-washed fritillary (Argynnis paphia, keisarinviitta) is one of the opportunist butterflies that has benefitted most from the warming climate in N Europe. When I started with butterflies in early 1980s, this species was rare and occurred in a narrow area in SE Finland. 1/2

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Juha Pöyry @poyryjuha.bsky.social · Aug 15

The Sooty copper (Lycaena tityrus, tummakultasiipi) is an expansive species in N Europe that was first found in Finland in 2009, but only in recent years it has gained a stronger foothold along the S coast of the country. The pic shows a female butterfly (Hanko, 14 August 2025).

Juha Pöyry @poyryjuha.bsky.social · Aug 12

A news release on the main findings: www.helsinki.fi/en/news/life...

Northern losses and southern gains – climate change reshapes moth communities across Finland | University of Helsinki

Climate change is transforming moth communities across Finland. According to researchers at the University of Helsinki, cold-adapted species are disappearing in the North while Southern Finland is see...

www.helsinki.fi

Juha Pöyry @poyryjuha.bsky.social · Aug 12

A new paper demonstrates a clear latitudinal gradient in responses of the Finnish moth communities to warming climate. This work is based on the Finnish #mothmonitoring dataset gathered @syke.fi.

Emilie Ellis @e-ellis1.bsky.social · Aug 12

🚨 Just out in Nature Communications from my current work with fantastic collaborators @rececochange.bsky.social !

We show that moth communities are experiencing an overall “warming,” with a clear latitudinal pattern: extinction in the north and colonisation in the south.
doi.org/10.1038/s414...

Recent community warming of moths in Finland is driven by extinction in the north and colonisation in the south - Nature Communications

As Finland’s climate warms, cold-adapted moths are disappearing in the north while warm-loving species move in from the south. This shift in insect communities highlights the threat climate change pos...

doi.org

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Juha Pöyry @poyryjuha.bsky.social · Aug 12

The Short-tailed blue (Cupido argiades, kannussinisiipi) is having another good year in Finland, and can now be found in good numbers in e.g. clover fields. This newcomer species has clearly benefitted from warming summers.

Reposted by Juha Pöyry

Nahel Belgherze @wxnb.bsky.social · Aug 6

This is unbelievable.

The high temperature at one of Finland’s northernmost weather stations, in the municipality of Sodankylä (Lapland region) within the Arctic Circle at latitude 67.3°N, reached at least 25°C for 26 days in a row.

Records date back to 1908.

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Reposted by Juha Pöyry

Richard Fox @richardfoxbc.bsky.social · Aug 7

Cool new research by @e-ellis1.bsky.social Moths & hoverflies are more sensitive to urbanisation than bees, but urban trees boost moth species richness in UK cities. #teammoth 🌍 royalsocietypublishing.org/doi/10.1098/...

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Reposted by Juha Pöyry

Journal of Applied Ecology @jappliedecology.bsky.social · Aug 6

A meta-analysis found that high-density managed honeybee populations can:

👉disrupt local biodiversity🌏
👉reduce pollinator richness🧪
👉alter plant-pollinator relationships🐝
...all with minimal benefits to crop yields!

Calls for evidence-based hive density guidelines 📑

🔗 doi.org/10.1111/1365...

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Reposted by Juha Pöyry

Phil Stevenson @philstevenson.bsky.social · Jul 16

Negative ecological impacts of honeybees begin at densities below recommended levels for crop pollination. doi.org/10.1111/1365...

Negative ecological impacts of honeybees begin at densities below recommended levels for crop pollination

The ecological consequences of high-density honeybee management are significant, calling for a re-evaluation of pollination strategies in agricultural landscapes. Setting evidence-based hive density ....

doi.org

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