Blocks and maps

Data for the Connecticut Bird Atlas will be organized into 601 blocks, following the same system used for the first state atlas. These blocks were created by taking the grid of United States Geological Survey quadrangles and dividing each quad into six. Each block is approximately 9 square miles (3.2 x 2.8 miles) in size. The new project has five more blocks than the first atlas because we have created additional blocks for small patches of coastal land and offshore islands that were not included in the first atlas.

Choosing a block: Blocks can either be chosen by you or assigned by a regional coordinator. If you have a specific area that you would like to survey, you should go to the Block Map on the Maps menu and see if the block has already been assigned to someone. If it has not, click on the words “Sign Up!” and an email will be generated for you to send to the regional coordinator to alert them to your interest. The regional coordinator should get back to you within a few days to confirm whether or not the block is available. (If an email is not generated, ensure that you have an email address associated with your browser and that your security settings are not set to prevent the email from being created. If all else fails, just send an email direct to

If someone has already been assigned a block, then you can do one of two things. Ideally, we would like you to pick another block that has not already been assigned, because that helps us achieve our primary goal of having at least some data from every block. If you are not sure which block to pick, the regional coordinator will have suggestions.

If you really want to collect data in your first choice block, you should feel free to do so, but we recommend that you coordinate your data collection with the person listed as the lead so as to spread out the effort and maximize the information that we obtain. Note too that anyone can submit observations from any blocks, even if they just have information on a single species. For more information on this, see the section on Incidental Observations.

Block maps: Once you have adopted a block, go back to the Block Map on the Maps menu where you will be able to download a Google Earth map of the area as a pdf file that you can print out and use in the field. For each block, you can choose between maps showing “satellite” or “terrain” view. If you are familiar with using Google Earth, you will also be able to download the block grid and a map of public lands from that page, so that you can put this information on your phone for use in the field.

Before you begin field work, we recommend that you study the satellite map, noting any roads, trails, and other landmarks that will help you locate the boundaries of your block in the field and gain access to key habitats. Also look for features that indicate different habitats within the block so that you can be sure to visit a diversity of locations and maximize the number of species that you find.