Jacob Drucker

Sharing this work brings me immense joy and would be impossible without my coauthors @bvdbirds.bsky.social, @aladino123.bsky.social, Nick Bayly, John Bates, Wilmer Ramirez and especially Adriaan Dokter who has been a world class mentor and collaborator. Can't wait to see where our work goes next!

Given the weak link between wind support and nightly migration at our study sites, predicting high-volume migration events to target for conservation action such as lights-out initiatives may be harder in tropical cities like Bogotá, Medellín, and Calí 🧵9/10

Our findings also build on an emerging picture of how flyways are structured in Colombia. We found the highest volume of birds funneling through the Magdalena Valley in fall as birds aim for the Andes as an overwintering destination and for destinations deeper into South America. 🧵8/10

It's spectacular to see birds flying 3000 m above the Amazon when headwinds headwinds are closer to ground level as seen in this week-long profile from Guaviare. Check out the switch in altitude with the wind! These switches drive the migration pulses we see during spring in the Orinoco Basin 🧵7/10

Wind support may not drive which nights birds choose to migrate but does play a big role in altitude selection, especially when navigating spring headwinds 🧵6/10

Since it doesn't pay to wait for optimal conditions nightly variation in the volume of migration is also much lower in Colombia. I.e. more than twice as many nights are needed to capture half of the total seasonal migration in the Magdalena Valley than in Illinois. 🧵5/10

Vertical profiles of wind support across height highlight just how much more variable wind is across altitude and between nights in Colombia than in Illinois, USA. Wind at our study sites in Colombia is similar across the year but in Illinois looks like a bowl of spaghetti! 🧵4/10

Wind helps birds travel huge distances while conserving energy which is a big part of why cycles of warm fronts and cold fronts drive the nightly volume of migration at temperate latitudes. But how is wind relevant for birds in the tropics, where weather operates at a much finer spatial scale? 🧵3/10

Stable atmospheric conditions underlie a steady pace of nocturnal bird migration in the tropics | Proceedings of the Royal Society B: Biological Sciences Seasonal migrations between temperate and tropical latitudes have evolved repeatedly across the tree of life, but we know little about how tropical environments have shaped this life history strategy. In this first aeroecological radar study in South ...

You can find the paper here or on my Researchgate, and read on for details! 🧵2/10

royalsocietypublishing.org/doi/10.1098/...

Our paper about the flow of nocturnal bird migration through Colombia is finally out today in #ProcB! Using weather radars operated by the #IDEAM, we found that low variability in wind underlies a pace of migration that is far more gradual than at temperate latitudes. #Ornithology 📡🪶🇨🇴

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Volunteer raptor migration counter TROPICOS Colombia is seeking an experienced Hawk Counter to join our spring migration team at the Tolima Raptor Count, the only active spring raptor count site in South America that is part of the HMA...

What I would give to help count raptors with the legendary Esther Vallejo in Colombia this spring! If you can, consider applying! ornithologyexchange.org/jobs/board/v...

Preparing for remote work during holiday travel feels too much like preparing for a field season

Sometimes you want to work late but you drank too much chocolate milk