A Census for the Natural World

A Census for the Natural World
September 4, 2018 by: Robinne Gray

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Every ten years, the U.S. Census Bureau counts us. But who counts the animals and plants that share the world with us?  During a BioBlitz, you can!

This September 6-9, anyone with some curiosity, a smartphone camera, and a willingness to get outside can join in the Anacostia River BioBlitz, an effort to identify and count as many species as possible throughout the Anacostia watershed. And that means any and all species, from the tiniest insects and aquatic plants to the largest trees and mammals. And everyone, from beginner to expert, can be a part of this citizen science effort.

What’s a BioBlitz?

The BioBlitz concept, developed by the National Park Service and popularized by National Geographic, is a crowd-sourced biological survey organized in a particular place during a specific window of time, often as a collaboration with professional scientists. While wildlife biologists may closely monitor the number and location of some animals, their work tends to be concerned only with individuals of a specific species – say, of elk or chestnut populations. By contrast, BioBlitz counts are crowd-sourced, unofficial and impressively broad inventories of how many different species are spotted, and help us tune in to the wonderous biodiversity (variety of life forms, or species richness) in our part of the mid-Atlantic.

The 2018 Anacostia River BioBlitz

The Anacostia BioBlitz has two parts: the public event will be held Saturday, September 8 from 9:00 a.m. to 1:00 p.m. at Kenilworth Aquatic Gardens near the DC/Maryand border.  To record and share your field observations during the BioBlitz, you’ll need to download the free mobile app iNaturalist, an online social network that lets you upload and tag your photos to our local BioBlitz project, Biodiversity of the Anacostia River.

At the event, you’ll have help from experienced and knowledgeable naturalists who can assist you with using iNaturalist and with identifying what you see. These friendly experts will also offer walks throughout the morning to look for birds, fish, fungi, plants, reptiles, insects, and more. The four-day “virtual” event, during which you can record your watershed observations at any time or day or night, runs Thursday through Sunday,

What does a BioBlitz tell us?

A count of species in any given year provides a snapshot in time, showing “who” may be found in a particular place and season: What is that pretty blossom? Is that an osprey or an eagle flying above? Is this plant native or invasive? What kind of mushroom is that? A BioBlitz is an opportunity to sharpen our skills in observing and identifying – and appreciating – what is around us.

Year to year, the number of sightings can give clues to changes that might be occurring. A significant difference observed from one year to the next could indicate a temporary or cyclical change in habitat or behavior; for example, in certain years the periodical cicadas emerge and are seen in large numbers, and varying weather patterns can affect bird migration or the flowering and fruiting of plants. An area where land is cleared for development may show reduced counts of species in the area. Some new species may be sighted, perhaps signaling the resurgence of an animal in a particular area or the arrival of a pest, or the spread of an invasive plant.

The handwritten phenological records kept by amateur naturalists in earlier decades are helping scientists track broader changes over time and geography. For example, sightings that change considerably over a longer period of years could indicate the range of a species expanding or shrinking. While some changes are beneficial and welcome, loss of biodiversity due to climate change is a long-term concern that is being tracked.

If you’d like to join the 2018 Anacostia River BioBlitz, please download the iNaturalist app and create an online account. You may also learn more and register for the event by clicking here.

Robinne Gray

Robinne Gray

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