There are a number of ways to map ringing recoveries. They vary in the degree to which they can be customised to suit individual preferences, and hence in the complexity required to use them. This Powerpoint presentation (PPT, 8.79 MB) provides a brief introduction to three different methods. The best way to learn how to use these things is just to try them; the worst that can happen is an increase in coffee consumption and swearing levels. Don't forget Google (note: other search engines are available), if you're having a problem chances are someone else did as well. Start your query with the method you're using (eg Google Static maps or R) then put in the key words of your question, it's surprising how often the answer will be on the first page of results. If you get stuck, feel free to email Rob Rob at BTO HQ who will try to help if he can.
Google Maps and Google Earth require recovery locations to be specified in terms of decimal degrees of latitude and longitude. If you have positions in degrees, minutes and seconds then simply divide the minutes by 60 and this to he degrees value (for extra precision, divide the seconds value by 3600 and add that too); negative values are used for positions West of the Greenwich Meridian or South of the Equator. If you have Ordnance Survey grid references the GridRat or Where's the Path websites are quite helpful for working out the conversion. If you have many positions to convert, the Ordnance Survey provides an Excel spreadsheet which will do the conversion for you; Google "OS grid reference lat long conversion" to find others.
The "Old-fashioned Way"
If you have just a few recoveries to plot, but would like arrows, labels etc, remember the quickest way may simply to be to do it 'by hand' i.e. copy a map into 'Powerpoint', 'Present' or an image-editing package and add them yourself. In addition to the usual Google imagery, you can download a nice (and free) worldmap from Natural Earth (hint: click the "raster" button, and be careful, file sizes range from 47MB for the 1:50m map to over 300MB for the 'large' 1:10m scale maps). Alternatively, NASA's 'Blue Marble' map is a good satellite image (the files are available in two different sizes, two different formats and with the upper left corner of the map in four different locations; for most purposes the first link, to a 2MB jpeg file, should suffice). If you fancy something different, browse the University of Austin's Perry-Castañeda Library Map Collection (caution: browsing this may seriously distract you if you are of a curious disposition, virtually all the maps are free to use, see the FAQ).
Google Static Maps
Google's Static Maps provide quite a simple way of presenting recoveries for one or a few individuals by effectively creating a custom webpage. Because these are essentially static images (the clue is in the name) there is a limited amount that can be done with them beyond simple presentation but, because of their simplicity, they are quite good for including in blogs, websites and for some printing purposes. This pdf (PDF, 22.33 KB)has a template for some of the more commonly used specifications with the different bits annotated to explain what they do, but full details can be found on the Google website. The North Thames Gull Group website has an example of what can be achieved using this style of maps.
Google's Earth application allows for much greater interactivity in presenting recovery maps - you can zoom in on particular recoveries, or (potentially) click on the markers to reveal further information. This added functionality means that the process of creating the maps is slightly more complicated, but there are many tools on the interweb to help you. Google Earth reads files that are in KML (Keyhole Markup Language) format and a number of websites offer the ability to convert spreadsheet type files into KML files. One of the easiest to use is the Earthpoint site as explained in the Powerpoint presentation.
R package maprec
R is free statitistical package. Part of its power (and beauty) lies in the fact that it is open source, so although it has a relatively small core, users from around the world have contributed add-ons (packages) to perform a myriad different tasks and analyses. One such is the package maprec which allows mapping of ring recoveries, and is what is used to produce many of the maps in the Ringing Report. You can download R and the maprec package (ZIP, 102.09 KB). Please Note: Loading the package, and the background maps may take some time (depending on the speed of your connection possibly a couple of minutes), please be patient!
Happy exploring and mapping!