GBIF Web Map Service (WMS)

Introduction

The Global Biodiversity Information Facility (GBIF) data portal, provides access to the World's largest collection of online records for biological specimens and observations. The Canadian Biodiversity Information Facility (CBIF) in cooperation with GBIF now provides Web Map Service (WMS) access to these records. This opens up access to millions of biological records for online mapping purposes.

WMS is a technical specification standardizing the way in which client-software applications request maps from a map server. This enables the development of Internet mapping applications that can combine on a single map in real time and dynamically several layers of information provided by one or many servers. You can see an example of such application by using our mapping client that can map multiple distribution layers (taxa) from the GBIF data portal.

Instructions for programmers

Technical instructions below are intended for web application developers and are not meant for casual end users. The following describes the technical details required to use the GBIF WMS layers. This WMS service makes dynamic queries against the GBIF Data portal based on scientific names (e.g. Sinapis arvensis). The maximum point coordinates returned are currently set to 10,000 for reasons of performance. The first time that a taxon is queried it might take some time (e.g. a minute to retrieve and parse 10,000 geographic coordinates). From then on each WMS layer is returned almost instantly because the responses are cached for a period of time. Multiple taxon layers can be plotted together using differing shapes, colors and sizes of points as described below. The coordinates are queriable and return the user to the GBIF data portal to retrieve the information for a specific point (using the GetFeatureInfo query).

Standard requests

• GetCapabilities - Returns an XML document containing a description (metadata) of the capabilities of the server. This XML document that is not normally viewable in a browser. Therefore save the result and view with any text or XML editor.
• GetMap (projected) for Sinapis arvensis - Returns a map image of specified coverage and dimension - for ex., a projected distribution of Sinapis arvensis.
• GetFeatureInfo - Returns primary data underlying a particular point of distribution on the map.

Additional variables

The following non-standard variables can also be sent with a GetMap request to allow for multiple WMS layers with differing points to be combined onto a single map. If these extra variables are not used then the default points are red (RGB value: 250 0 0), the shape is star and the size is 8 pixels. For example, the GetMap Web address above will retrieve a layer for Sinapis arvensis with purple stars of size 8 pixels.

&COLOR=

The colors are in RGB order separated by a space (use the %20 encoding for the space). For example the default is red which is RGB 255 0 0 and this becomes &COLOR=250%200%200

&STYLE=

The style refers to possible shapes of the points. The available styles can be one of type: circle, cross, plus, square, star, tent, triangle. E.g. &STYLE=circle

&SIZE=

Size affects the rendered size of the point in pixels. Use the numeric value e.g. &SIZE=8

Using the map client in your own web pages:

The mapping client mentioned above can also be used by itself without the CBIF headers and footers. You can add this mapping application as a separate page or embed it either as a <FRAME> or <IFRAME> from your own website by simply calling this application in the following manner:

• In English: http://www.cbif.gc.ca/mapdata/cbif/gbifwmsmc.php.
• In French: http://www.scib.gc.ca/mapdata/cbif/gbifwmsmc.php?p_lang=fr