CNC 2021

Mark your calendars for CNC 2021! From April 30th (Friday) to May 3rd (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 4th to May 9th before results are announced on May 10th.

Fall Bioblitz

Join Philadelphia and its surrounding counties as we document our fall biodiversity. We’ve done the City Nature Challenge in the spring, but now it’s time to see what we have around us in the fall.

From September 25th (Friday) to September 28th (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. Can we beat our spring totals from the CNC in the fall? What new species are we going to find? Come participate in some community science and help us find out.

Simply download the iNaturalist app on your Android or iOS device and start making observations between September 25th and 28th for them to count towards the bioblitz. You can make observations in your own house or backyard, on your walks around the neighborhood, or anywhere you enjoy the outdoors.

Participating is exactly similar to the City Nature Challenge, except that it is in September. For more detailed instructions, check out our How To Participate page. You can also find more info on using iNaturalist in our Resources page.

Black Lives Matter

Black Lives Matter to the Philadelphia City Nature Challenge (PCNC). The Philadelphia City Nature Challenge Organizing Committee condemns all forms of racism, discrimination, and prejudice. We stand in solidarity with the Black community against systemic racism, white supremacy, and police brutality. We believe that nature is for everyone, but that can never be realized until we do everything we can to ensure that Black, Indigenous, and People of Color feel safe in the outdoors. The experience of engaging in active or passive activities in natural areas, using binoculars, or observing wildlife in every facet of the public realm, is drastically different for different groups of people. BIPOC, and especially black people, face excessive scrutiny from white people when engaging in the activities they love as evidenced by the recent racist incident against Christian Cooper, a black birdwatcher in NYC. While that incident luckily did not end as badly as it could have, we all know how easily the situation could have been very different as we saw with the murder of George Floyd, Breonna Taylor, and countless others at the hands of law enforcement. We grieve with all of their families and loved ones, and mourn that their lives were taken far too early.

While Philadelphia is a diverse city, the naturalist community in Philadelphia isn’t so diverse. We acknowledge that we haven’t done enough to make sure that this is addressed and we aim to do better. We pledge to increase programs in under-served areas, and actively reach out to communities of color to make sure that they are represented in citizen science efforts.



As so much of Philadelphia life slows to a pause as we do our best to limit the spread of COVID-19, and as we realize that this isn’t going to end any time soon, we wanted to update you about our City Nature Challenge plans.

The CNC planners, based at the California Academy of Sciences and at the Natural History Museum of Los Angeles County, have decided to not cancel this year’s Challenge. We agree with them.

One of the great things about the CNC is its flexibility. At a time when group events can present health risks to the attendees and their communities, we can still take part individually. We can document the wildlife of our basements and back yards, and, to the extent possible, we can head off into our neighborhoods and green spaces on our own or in small groups of friends or family.

Indeed at a time of illness, stress, and isolation from our neighbors, connecting with nature outdoors can be incredibly therapeutic. We hope you can take part in the CNC as something we can still do safely as we take a break from our increasingly-homebound lives.

Happy iNatting!