Using and Obtaining Watershed Occurance Data in Freshwater Fish Identification

If you are a micro-fisherman, chances are you are a multi-species fisherman as well.  One of the joys and challenges of multi-species fishing is the identification of your catch.  A huge aid in freshwater fish identification is knowing what species are documented to occur in, or be absent from, the water you fish.  Distribution maps in field guides are a good general starting point, but are limited in the detail they can portray.  Sampling data is great if it can be obtained as it not only identifies the body of water, but the location on that body the fish was captured.  Care must always be given to differentiating between current data and historical data.  What was present in 1902 may not be today!  Detailed species occurance data is especially valuable while micro-fishing, as many of the trophies belong to Genera that have minute differences between species.  These differences are often very difficult or almost impossible to distinguish in the photos taken home from the field; therefore, occurance data is relied upon heavily.

While researching the identification of some micros from a recent trip, I discovered a cool site, NatureServe, that can produce a list of species currently occurring in any of the 2,064 watersheds of the 48 contiguous US.  Each species is identified as currently or historically occurring in the watershed.  Not only are the lists helpful, but each species is also linked to interesting data and information summarized for that species.  The NatureServe information includes life history and population status including a bibliography.  This new found capability was all good, but I often fished in creeks on my trips that I didn’t really know to which watershed they belonged.  I found a USGS site with interactive maps of watersheds so that I can now quite quickly identify the appropriate watersheds and subsequently produce the desired species lists.

Now, in planning fishing trips, using these sites I can be proactive and create these lists before I leave.  Taking them with me, they greatly assist in identifying opportunities, preparing goals and in the identification of those new Lifelisters!