Jeroen Reneerkens
@jeroen-reneerkens.bsky.social
760 followers 880 following 46 posts
Shorebird ecologist | #Sanderling | Avian migration | Greenland | Arctic | climate change | #ornithology |#shorebirds | #BirdMigration
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Reposted by Jeroen Reneerkens
wadertales.bsky.social
Reminder!
@jeroen-reneerkens.bsky.social appreciates reports of colour-ringed Sanderlings:
submit.cr-birding.org/projects/181/
Counts of adult/juvenile Sanderlings in flocks are great too.
Blog about the Greenland Sanderling project:
wadertales.wordpress.com/2019/10/04/t...
📷 @markaeaton.bsky.social
Reposted by Jeroen Reneerkens
waderstudy.bsky.social
Thank you to all of today's speakers for a really interesting array of talks! So much great research, and more on the way tomorrow! #IWSG2025 #waders #shorebirds #ornithology
Reposted by Jeroen Reneerkens
jeroen-reneerkens.bsky.social
A vagrant juvenile Sanderling turned up in Israel—likely after a single non-stop flight from the Dutch Wadden Sea. Here’s thread explaining why that’s remarkable and interesting. @wadertales.bsky.social @globalflyway.bsky.social #Birds #Migration
The colour-marked Sanderling photographed in Israel, still carrying its radiotransmitter
jeroen-reneerkens.bsky.social
Thanks to the Israel Bird Ringing Center for the report, Katya Rudnev for photos, and colleagues at @niozsearesearch.bsky.social for long-term ringing and tracking and to @natuurmonumenten.bsky.social for permission to perform our research on Griend.
jeroen-reneerkens.bsky.social
If you observe a colour-ringed Sanderling, please report it here (photos help!): submit.cr-birding.org/projects/181/

Reports are useful for studies of migration routes and survival. I am also interested in counts of adults and juveniles within flocks #CitizenScience
Sanderling <h4> 1 flag and 4 plain rings</h4>
submit.cr-birding.org
jeroen-reneerkens.bsky.social
Will the bird stay in Israel this winter, or continue to the East African coast (where many Siberian-origin Sanderlings likely winter)? We’re watching closely. #AfricanEurasianFlyway
jeroen-reneerkens.bsky.social
Are Sanderlings seen in Israel usually Greenlandic, or could this be Siberian origin? Was this juvenile born in Greenland—or farther east?
jeroen-reneerkens.bsky.social
Questions: Why the route change? Was this bird travelling alone (no experienced guides)? How often do juvenile Sanderlings push inland routes across Europe?
jeroen-reneerkens.bsky.social
Map shows all out-of-Netherlands sightings of Wadden Sea colour-ringed Sanderlings (locations within 5 km merged; dot size = number of birds). The Israel point stands out clearly as an outlier.
Map of Europe–Africa showing Wadden Sea colour-ringed Sanderling sightings; larger dots = more birds; Israel marked and linked to capture site with dotted line.
jeroen-reneerkens.bsky.social
Reported in Israel, ~3,200 km from the Wadden Sea. Given timing and track, a non-stop flight across much of Europe is likely. Photo credit: Katya Rudnev via the Israel Bird Ringing Center. @shai-blitzblau.bsky.social #Israel #Birding
jeroen-reneerkens.bsky.social
16 Sept (midday): Tracking shows the bird using mudflats near Griend, then moving SW, leaving the Wadden Sea in the SW corner—before turning SE. A sharp course change away from the coast. #Migration
jeroen-reneerkens.bsky.social
This juvenile was caught and colour-ringed on 27 Aug 2025 near Griend (Dutch Wadden Sea). A WATLAS transmitter was fitted to track fine-scale movements locally. @allertbijleveld.bsky.social @niozsearesearch.bsky.social #WaddenSea #Tracking
jeroen-reneerkens.bsky.social
Sanderlings pick their non-breeding site on their very first southward trip, at ~2 months old. They usually return there every year—just like they are faithful to a breeding area. Such early choices shape a lifetime of migration routes and conditions. #Shorebirds
jeroen-reneerkens.bsky.social
A vagrant juvenile Sanderling turned up in Israel—likely after a single non-stop flight from the Dutch Wadden Sea. Here’s thread explaining why that’s remarkable and interesting. @wadertales.bsky.social @globalflyway.bsky.social #Birds #Migration
The colour-marked Sanderling photographed in Israel, still carrying its radiotransmitter
Reposted by Jeroen Reneerkens
wadertales.bsky.social
Colour-ring readers jave contributed greatly to the science underpinning 1️⃣0️⃣ years of WaderTales blogs.
One of the best studies, in terms of feedback to observers, is the Sanderling project run by @jeroen-reneerkens.bsky.social.
More here:
wadertales.wordpress.com/2019/10/04/t...
#ornithology
Reposted by Jeroen Reneerkens
wadertales.bsky.social
This month, WaderTales will be ten years old.
I'm going to create a thread that highlights some of the research findings that have surprised me.
Plenty of "Wow!" & "I didn't know that!" moments.
Here's a link to the catalogue of 150 blogs
wadertales.wordpress.com/about/
#ornithology
jeroen-reneerkens.bsky.social
It is juvenile #Sanderling time!

Observers, please share your counts of adults and juveniles with me ([email protected]; do not use the address in ageing guide!). I will use them in population models to.

📄 Find the ageing guide here: bit.ly/3HQdb5M
Reposted by Jeroen Reneerkens
wadertales.bsky.social
Sanderling.
Just a few weeks old.
Imagine arriving in St Andrews, from Greenland.
Should you stay?
Or fly to England, Portugal, Mauritania or Namibia?
Where's best?
If only this bird could read:
wadertales.wordpress.com/2019/10/04/t...
#ornithology @jeroen-reneerkens.bsky.social
tsm23.bsky.social
Sanderling on West Sands, St Andrews. #birdingFife #BirdingScotland
jeroen-reneerkens.bsky.social
It is juvenile #Sanderling time!

I am very interested in counts of adults and juveniles to be used for population models. Please use the manual and send your counts to [email protected] (not to address in ageing guide!).

📄 Download ageing guide: bit.ly/3HQdb5M
jeroen-reneerkens.bsky.social
I recommend the well-illustrated blog post by Alaska Audubon on our recent paper in Global Change Biology led by Eveling Tavera Fernandez and Kirsty Gurney about the effects of climatic variation on timing of nesting in arctic shorebirds.

ak.audubon.org/news/arctic-...
Silver Lining for Shorebirds: New Study Shows Arctic Nesting Species Are Cued into Climate Change
Attentive long-distance migrants are following environmental cues better than expected, showing some shorebirds to be surprisingly adaptable.
eur01.safelinks.protection.outlook.com
jeroen-reneerkens.bsky.social
@alexanderlees.bsky.social Not necessarily so! This is just my experience from one location in a large NE Greenland. Colleagues elsewhere in NE Greenland are experiencing a lemming peak year with many snowy owls and great nest survival of shorebirds, as we experienced last year in Zackenberg.
jeroen-reneerkens.bsky.social
Certainly, I had just ringed them. I expected the parent to walk away with the chicks.
jeroen-reneerkens.bsky.social
Yes, that communication between adult and chicks sounds great, right?