Results City Nature Challenge 2021 in Luxembourg

Over 250 participants during City Nature Challenge 2021 in Luxembourg

City Nature Challenge: a global event

The City Nature Challenge (CNC) is an annual initiative of cities around the world, where citizens are called upon to observe and record wild species around them. This year’s edition focussed on the global collaborative effort to record as many species as possible. This year it took place between April 30 and May 3!

A total of 52,777 people participated in last week’s 6th annual City Nature Challenge! A total of 1,270,767 biodiversity observations were made in the 419 participating regions covering 44 countries. More than 45,300 species were documented, including more than 2,100 rare/endangered/threatened species. Despite the ongoing COVID-19 pandemic, we had over 10,000 more people participate compared to last year, and for the first time ever, we made over one million observations in the four days of the challenge! The City Nature Challenge also contributed to the most observations uploaded in a week on iNaturalist again - and also gave iNaturalist the first two weeks ever with over one million observations uploaded!
All the contributions made to the CNC2021 via iNaturalist can be consulted in the City Nature Challenge iNaturalist project.

City Nature Challenge Luxembourg

In Luxembourg, the CNC2021 was the third edition of the challenge organised by the ‘natur musée’. Though the absolute numbers for Luxembourg are lower than in previous years, the challenge can be considered a success. A total of 268 people participated and recorded a total of 5,341 observations with the iNaturalist app. A total of 888 different species were documented.
The area of the CNC2021 was once again extended to include the entire country to give the opportunity to everyone in Luxembourg to participate without needing to travel too far. All results for Luxembourg can be found in the City Nature Challenge 2021: Luxembourg iNaturalist project.
This year also marked the launch of the iNaturalist.LU portal and the official partnership of the ‘natur musée’ in the global iNaturalist network.

With 268 participants (2019: 415, 2020: 424), 5,341 observations (2019: 8,091, 2010: 5,913) and 888 species (2019: 942, 2020: 1,082) we unfortunately fell short of last year's count. However the quality of the contributed data can be considered significantly better this year! Much less “captive/cultivated” occurrences were reported and the percentage of already validated (research grade) observations of 60% (2019: 42%, 2020: 48%) is impressive and way above the global CNC average. A total of 316 specialists, from Luxembourg and all over the world helped identify and validate the reported occurrences.

Globally the most recorded species was the mallard duck (Anas platyrhynchos), in Luxembourg the most common species were the red deadnettle (Lamium purpureum - 78 observations), the common dandelion (Taraxacum officinale - 73 observations) and the wood anemone (Anemonoides nemorosa - 70 observations). Far off were the most common animal species: the western honey bee (Apis mellifera - 30 observations), the eurasian blackbird (Turdus merula - 27 observations) and the house sparrow (Passer domesticus - 24 observations).

Besides these very common species, some rare species for Luxembourg were recorded by amateurs and naturalists alike. Here are some of those noteworthy records:


Our special thanks goes to the top 5 users, which combined contributed 2,150 observations: @paul_luap (477 observations), @odovacrius (465 observations), @claudekolwelter (445 observations), @pinkgrasshopper (350 observations) and @bee-together (232 observations). But also those other that contributed each more than 100 observations: @hera-pt @svenjachristian @fraentz @ebbalux @krauselguy @cheidt @francisbirlenbach @marielouise2 @georges3 @michaely0907
Another big thanks goes to the users who contributed their time to identify what others found: @sleguil with 1,296 identifications (impressive), @svenjachristian 665 IDs, @paul_luap 435 IDs, @thierryh 320 IDs and @wollef 313 IDs.

We would like to express our gratitude to each and every participant (observer and identifier alike) and hope they had fun exploring biodiversity in Luxembourg and that they keep doing so using iNaturalistLU, thereby contributing valuable species occurrence data to the scientific community in Luxembourg and the world. We hope to see you again for the Nature Challenge 2022!

Posted on May 18, 2021 08:53 AM by paul_luap paul_luap


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