This week, Rochester joins an international competition to see which city can make the most observations in nature. You can participate in the citizen-scientist City Nature Challenge, which takes place from Friday, April 26, to Monday, April 29. Participants will use the smartphone app iNaturalist to identify and log the different wildlife species they find in parks, in one of the Genesee Land Trust nature preserves, or even on their own property. City Nature Challenge is organized on a global scale by the Natural History Museum of Los Angeles County and the California Academy of Sciences.

Friday, April 26, to Monday, April 29, everywhere. More information at citynaturechallenge.org and geneseelandtrust.org.