Guanacaste Dry Forest Conservation Fund

Our latest newsletter is out! 🌿 Inside: 1.6 million ACG insects reshaping estimates of global insect diversity, new climate research, community science in Bahía Santa Elena, Dan & Winnie—and a few newly named species. Read the latest from ACG: mailchi.mp/847ec6fd5bde...

🧪 🪲🐜🐛🦟🦗🐞🦋 How many insect species & why it matters. Have a listen to @dirch3.bsky.social speaking with #CBC radio about our recent @pnas.org paper about raising old insect diversity estimates! doi.org/10.1073/pnas... www.cbc.ca/listen/live-...

🧪 🪲🐜🐛🦟🦗🐞🦋 How many insect species & why it matters. An interview with @jonathanmccrea.bsky.social on RTE Ireland’s #Futureproof about that very topic via our recent @pnas.org paper about old estimates that need to be raised! doi.org/10.1073/pnas... (@ 15 min) podcasts.apple.com/ca/podcast/f...

What an extraordinary story. 💚🌳 @mongabay.com’s Rhett Ayers Butler beautifully captures Dan Janzen, Winnie Hallwachs, and the decades of people, science, and persistence behind the restoration and protection of Área de Conservación Guanacaste. A must-read: news.mongabay.com/2026/08/dani...

🧪 A piece in this week's @science.org "In Other Journals" section by Sacha Vignieri about our species number paper "So many more" doi.org/10.1126/scie... @gdfcf.bsky.social doi.org/10.1073/pnas...

New research estimates around 20 million insect species on Earth — doubling those facing extinction theconversation.com/new-research...

🦟🐛🐞New article out on the PNAS paper that is based on decades of work in Área de Conservación Guanacaste, Costa Rica, and that reshaped our understanding of life on Earth. www.pnas.org/doi/10.1073/...

🧪 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 All the data is available here: doi.org/10.5683/SP3/... @gdfcf.bsky.social @rpuschen.bsky.social 🧵 end.

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 Thanks to all co-authors, in particular José A. Hernández Ugalde from CONAGEBio, & all associated with ACG & GDFCF – the hybrid association formed to aid with the development, protection, & sustainability of ACG. doi.org/10.1139/gen-... @gdfcf.bsky.social @rpuschen.bsky.social

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 Nearly 4 million records and 152 891 species. That’s a lot! (and there’s more to be found!) doi.org/10.1139/gen-... @gdfcf.bsky.social @rpuschen.bsky.social

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 Were there patterns in what groups we found? 🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰A LOT OF FLIES 🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰🪰 (and also loads of Hymenoptera, Coleoptera and Hemiptera). doi.org/10.1139/gen-... @gdfcf.bsky.social @rpuschen.bsky.social

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 After nearly 4 million records, we found extremely high turnover. Most species were exclusive to a single region & each life zone harbors unique assemblages, strongly associated with temperature and precipitation doi.org/10.1139/gen-... @gdfcf.bsky.social @rpuschen.bsky.social

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 Only 3.6% of species we recovered were linked to formal names and so we used DNA barcode derived ‘BINs’ as species proxies. doi.org/10.1139/gen-... @gdfcf.bsky.social @rpuschen.bsky.social

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 Most samples emerged from Malaise traps in national biodiversity initiative, BioAlfa. We analysed these Malaise traps across Costa Rica sampled between 2017 and 2023. doi.org/10.1139/gen-... @gdfcf.bsky.social @rpuschen.bsky.social

🧪 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 We analysed 3.78 million DNA barcodes from 152,891 Costa Rican insect species. Our results reveal limited community overlap across ecosystems, suggesting unique species assemblages in each life zone. doi.org/10.1139/gen-... @gdfcf.bsky.social @rpuschen.bsky.social 🧵

🧪 Mountain insects are running out of room as the planet warms: www.earth.com/news/mountai... 🧪🌋🪲

Tropical insects may be running out of room as temperatures rise | EurekAlert! www.eurekalert.org/news-release...

🧪 🪲 🌋 🌡️ The little things of ACG are teaching us much about the world. We enthusiastically thank ACG for protecting & preserving these species & spaces. @gdfcf.bsky.social @alexandreloureiro.bsky.social www.pnas.org/doi/10.1073/...

🧪 🪲 🌋 🌡️ However, as predicted by Janzen’s Mountain Passes, most of these species do not move much; and eventually, there will be nowhere higher to go. @gdfcf.bsky.social @alexandreloureiro.bsky.social www.pnas.org/doi/10.1073/... 🧵

🧪 🪲 🌋 🌡️ How to deal with the climate crisis? Refuge in the soil may provide temporary respite from rising temp. Larger spp that can move may move upslope and find respite in cooler temperatures. @gdfcf.bsky.social @alexandreloureiro.bsky.social www.pnas.org/doi/10.1073/... 🧵

🧪 🪲 🌋 🌡️ Tropical forest communities are vulnerable across elevation in different ways. This highlights the critical protective role that the ÁCG plays in preserving habitat these species and others like them. @gdfcf.bsky.social @alexandreloureiro.bsky.social www.pnas.org/doi/10.1073/... 🧵

🧪 🪲 🌋 🌡️ High-elev cloud forest spp r likely not capable of dealing with the coming temp. Low-elev dry forest spp, have higher heat tolerances, but r already exposed to temps that can exceed their thermal limits. @gdfcf.bsky.social @alexandreloureiro.bsky.social www.pnas.org/doi/10.1073/... 🧵

🧪 🪲 🌋 🌡️ Diverse tropical leaf litter-dwelling rove beetles in Área de Conservación Guanacaste (ACG) Costa Rica (a UNESCO World Heritage Site), show how thermal tolerance can change with elevation. @gdfcf.bsky.social fcf.bsky.social @alexandreloureiro.bsky.social www.pnas.org/doi/10.1073/...

🧪 🪲 🌋 🌡️ When are things too hot to handle? Our new paper on insect thermal tolerance across elevation in @pnas.org nas.org suggest perhaps not too far in the future. @gdfcf.bsky.social sky.social @alexandreloureiro.bsky.social www.pnas.org/doi/10.1073/... 🧵

New research from Área de Conservación Guanacaste! Congratulations @natingui.bsky.social and @isabelvargas.bsky.social #womeninscience #woodthrush #cienciatica #bioave #costarica #birds

New study shows there may be 2-3x as many insect species as previously estimated, owing significantly to the diversity of parasitoid wasps!

🧪 "Más de tres décadas de investigación en el ACG transforman la estimación mundial" "More than three decades of research at the ACG are transforming global estimates." www.acguanacaste.ac.cr/noticias/not...

This isn't just a paper about insects. It's a demonstration of what decades of biodiversity inventory, conservation, and scientific collaboration can achieve. Congratulations to Dan & Winnie, the parataxonomists, and all the authors on this remarkable PNAS publication. www.pnas.org/doi/10.1073/...

🧪 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 "Study finds number of insect species on Earth is more than double previous estimates" 🎁link to a wonderful article by @ivansemeniuk.bsky.social in the @theglobeandmail.com about our #OA PNAS paper doi.org/10.1073/pnas.... @gdfcf.bsky.social www.theglobeandmail.com/gift/c231c7b...

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 In many ways, the deeper story is that patient, long-term inventory work in one very special place, involving the people of that place, has generated insights about biodiversity at a global scale. @gdfcf.bsky.social doi.org/10.1073/pnas...  grateful to have been part of the team🧵

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 In our paper, we (an international team of authors) root our answer in the globally unique biodiversity hotspot, (and UNESCO World Heritage Site), in northwestern Costa Rica, the Área de Conservación Guanacaste (ACG). @gdfcf.bsky.social

🧪🧵 🪰 🐜🪲🐞🦗🐛🦋🪳🦟 How many species of insect are there?  A seemingly simple question, but one that has been 'bugging' scientists for years.  Our work out today suggests that there are millions more than we had previously expected.  doi.org/10.1073/pnas... @gdfcf.bsky.social

A new species of scale-covered marine worm, Sthenelais onca, has been documented along the Pacific coast of Costa Rica. It is characterised by a jaguar-like color pattern! Read more: zookeys.pensoft.net/article/1764...

NEW SPECIES ALERT! Researchers with the BioMar project have discovered a new species of marine worm in Área de Conservación Guanacaste. #newspecies #biodiversity #costarica #science #marineworm #marinebiodiversity Read more here: zookeys.pensoft.net/art.../17644...

Our latest newsletter is out today. Please read and share. Thank you! mailchi.mp/eee818ebe3bb...

Inspired by this @karaman.is #TidyTuesday example to use his format to plot elevation rather than depth! Here are three years of air temperature data across 1500 m of elevation in #ACG #CostaRica from sea level (outer band) to cloud forest (centre) 🙏 for the example!! @gdfcf.bsky.social

🌿✨ A new species for science! Meet Cryptocarya costaricana, a newly described tree in the family Lauraceae. 🇨🇷 Co-authored by botanist Nelson Zamora, who works closely with the parataxonomists on the ACG plant bioinventory. www.scilit.com/publications...

www.theguardian.com/environment/...

“What I see when I'm walking through the forest, I just do not feel that the birds are having any kind of food,” Dan Janzen says. “No insects.” Birds are vanishing from tropical forests. Is another ‘silent spring’ coming? | Science | AAAS www.science.org/content/arti...

Here’s a view of a deceased Costa Rican nightjar slowly being turned into Costa Rican ants in #ACG @gdfcf.bsky.social youtube.com/shorts/kqwsY...

🧪🪰🧪 More #ACG diversity described! Santarosamyia woodorum sp. nov. Fleming AJ, Smith MA, Hallwachs W, Janzen D (2025) A new genus and a new species in the tribe Eryciini ( #Diptera , #Tachinidae ) from Area de Conservación Guanacaste. @bdj.pensoft.net doi.org/10.3897/BDJ.... @gdfcf.bsky.social

🍃Our End of Year newsletter is just out today! Thank you to all of our supporters for helping us protect one of the most remarkable places on the planet: Área de Conservación Guanacaste. Happy Holidays! mailchi.mp/040b71d05c06...

Successful Master's thesis defense of my student Isabel Vargas at the University of Costa Rica. She studied environmental and forest structure factors affecting Wood Thrush occupancy in Northern Costa Rica Project funded by @gdfcf.bsky.social

"After 55 years, the world’s most ambitious caterpillar inventory will come to a close. This monumental project in ACG has reared 870,000 caterpillars, of 8,000 species of butterflies and moths, and 18,000 species of wasp parasites—all documented by a team that grew to 30 local parataxonomists."

Happy to share our latest newsletter! The latest GDFCF and Area de Conservación Guanacaste news is here: mailchi.mp/54601d57a15d...

🧪 Very honored/excited to take part in this paper analysing & releasing 🐛 caterpillar rearing info from #ACG #CostaRica collected by #DanJanzen and #WinnieHallwachs and the #parataxonomists of @gdfcf.bsky.social doi.org/10.3389/fevo... Figures from data available at doi.org/10.5683/SP3/...

🧪 🪰 Happy to see this large data release and analysis of decades of #tachinidae collected by #DanJanzen, #WinnieHallwachs and the #parataxonomists of #ACG @gdfcf.bsky.social in #CostaRica. So much diversity! Paper here: doi.org/10.3390/d170... Data here: doi.org/10.5683/SP3/... 🪰 🧪

Fascinating new research on spectral #bats conducted in Área de Conservación Guanacaste #hugs #murcielago #batconservation #science #costarica @plosone.org These Bats Like to Give Hugs and Play With Bugs www.nytimes.com/2025/08/20/s...

How do Rufous-and-white Wrens respond when this 3D-printed owl is presented near versus far from their nest? Find out in Dr. Natalie Sanchez' talk "Singing in the face of danger" today at 16:00 in Grand Ballroom A at #AOS2025. 🦉🇨🇷🎶 @natingui.bsky.social @gdfcf.bsky.social @lincolnsavi.bsky.social

New paper out in Frontiers in Ecology & Evolution on #caterpillar diet in Área de Conservación Guanacaste. Authors include GDFCF's taxonomists in Costa Rica, Dan Janzen and Winnie Hallwachs, @alexsmithants.bsky.social, and Scott Miller. #science #Lepidoptera www.frontiersin.org/journals/eco...