A BioBlitz is a 24-hour inventory of all living organisms in a given area, often an urban park. It has the dual aims of establishing the degree of biodiversity in an area and popularising science. Botanists, mycologists and entomologists all play a role. Some BioBlitzes are an annual event.

Scientists establish a base at a point close to the area and provide expertise in identifying organisms found by the public as well as doing their own inspection of the area.

A full BioBlitz must take place over a full 24-hour period as different organisms are likely to be found at different times of day. Schools may organise BioBlitzes over a shorter period of time, but the results will less accurately show the variety of species in the area.

At a BioBlitz in New York City's Central Park in 2003, 393 plants, 78 moths, 14 fungi, 10 spiders, 9 dragonflies, 2 tardigrades, 102 other invertebrates, 7 mammals, 3 turtles, 46 birds and 2 frogs were found.

The list of events below is not comprehensive.

United States of America

• Connecticut: The Center for Conservation and Biodiversity and Connecticut State Museum of Natural History have held a BioBlitz each year (except 2004) since 1999. See [1].
• District of Columbia: A BioBlitz at the Kenilworth Park and Aquatic Gardens in Washington, D.C. in 1996 found approximately 1000 species. See [2]
• Illinois: The Field Museum of Natural History and other organisations held a BioBlitz in Chicago in 2002. See [3].
• Missouri: Several organisations collaborated on a BioBlitz at Forest Park in St Louis in 2004. See [4].
• Vermont: The Vermont Institute of Natural Science held a BioBlitz in 2004 at Hartford. See [5]
• New York: A BioBlitz at Central Park found more than 800 species in 2003. See [6]

Canada

• The Canadian Biodiversity Institute has held annual BioBlitzes since 1998. See [7]

Australia

• The Woodland Watch Project (part of the World Wildlife Fund has an annual BioBlitz in wheatbelt areas of Western Australia. See [8]

New Zealand

• Landcare Research held BioBlitzes in Auckland in 2004 and 2005, and in Christchurch in 2005. See [9].