Philadelphia City Nature Challenge


CNC 2023

Mark your calendars for CNC 2023! From April 28th (Friday) to May 1st (Monday), we’ll be documenting the plants, animals, and fungi in Philadelphia, Delaware, Montgomery, and Bucks counties in PA and Camden, Gloucester and Burlington counties in NJ. The Identification phase runs from May 2nd to May 7th before results are announced on May…

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Welcome to the Philadelphia City Nature Challenge! Between April 28 and May 1, 2023, Philadelphia and its adjacent counties will be competing against other cities in the world to see who can find the most species in their regions. If you are interested in contributing and helping Philly win, download the iNaturalist app (or visit the website) and start documenting the wildlife in your area. You can also visit our project page to see the latest observations as they come in.

A lot of people think cities are mostly devoid of wildlife; there are the pigeons hanging out on buildings, the sparrows in city parks and the rats running around our alleyways, but that’s about it. This could not be farther from the truth. The City of Philadelphia alone has recorded more than 325 species of birds. Numerous butterflies including monarchs live and breed in the city. There are snakes, frogs, dragonflies, foxes, bats, and much more to experience in our area. The City Nature Challenge gives us a way to explore and document the biodiversity in the cities and suburbs we call home. This, in turn, is useful for science and conservation.

For information on the City Nature Challenge, tips on participating and to see the other cities competing in 2023 check out the City Nature Challenge page.

We thank the Penn Treaty Special Services District (PTSSD) for their continued funding for our event. The funding helps us spread the word about the Philadelphia City Nature Challenge via signage, social media, and this website. We also thank PTSSD as well as Weavers Way for helping us empower naturalists to make observations for community science by providing tools like loupes and bug boxes.

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