Worcestershire Record No. 27 November 2009 p. 6

John Partridge

The main use that I have for the Gateway is to see where a species has been recorded within the British Isles. I use this to check on the ‘commonness’ of a species, to see whether I have found something of more importance, to see whether it is spreading, or to find that what I have identified is highly unlikely and it might be better to try again or seek advice.

Find the site with Google, or go to data.nbn.org.uk

When the NBN page appears, there are two places that you can enter the species name to find – either top right or in the centre lower down:

Search for Species or Sites

Type in the name of a species or a wildlife site:

If your species is found, you will be given four choices:

The top choice ‘Grid Map’ enables you to produce a map that shows how the distribution has changed over a number of years, by typing in year ranges for the different colours. I have to admit that I find it difficult to see the three colours at the resolution shown, but selecting ‘large map’ at the bottom makes things better. It has the usual problem that later years ‘overwrite’ earlier years which can hide movement.

The third choice ‘Interactive Map’ allows you to see more detail of the records, by showing the level of recording – to 10km, 1km or 100m (2-figure, 4-figure or 6-figure grid reference). This may only reflect what the data owner is allowing you to see. To see a smaller area, use the Zoom function – click on ‘Zoom in’, then outline the area you want to look at, and the map will expand for you.

It is also possible to put a site into the Search, and download a species list. This is of limited use at present, since most of the records are only available at low resolution (1 or 2 km), so you will tend to get all the species within say the 1 km square that includes your site. This is unlikely to be of value, and it would be better to try your friendly local record centre wbrc.org.uk.