November 8, 2015
by UC Davis Center for Watershed Sciences
By Nick Santos
The question is foundational to conservation biology and policy. To take a conservation action, you need to know where to act. And, yet, for decades stewards and researchers of aquatic fauna have been sorely lacking in tools to systematically collect, store and map data on where California’s freshwater fishes are located.
A reliable and comprehensive compilation of standardized species data is especially important for tracking California’s 133 native fishes because 100 of them are officially designated as being in trouble – “endangered” or “threatened” with extinction or otherwise of “special concern.”
This need led the UC Davis Center for Watershed Sciences to develop “PISCES,” an open-source suite of data and software providing the most comprehensive and accurate information on current and historic ranges of California’s fishes.
The center has just released PISCES to the public. The software and data can be downloaded for free from its website. The data also can be viewed from interactive maps on the website showing species ranges or species richness.
More than a data aggregator, PISCES converts different forms of data to a standard format and provides easily updatable, high-resolution maps outlining species’ ranges with the best and latest location information available. The program also produces summary California maps showing overall distribution of fishes, patterns of biodiversity and areas where biological data are lacking.
Watershed Sciences researchers have already deployed PISCES on several projects, including:
- Providing the California Department of Fish and Wildlife with information to manage fish species of special concern
- Assessing the ecological health of 17,000 Sierra meadows
- Locating “hot spots” with the highest concentrations of aquatic species in trouble
- Evaluating impacts of the ongoing drought on native fish
- Assisting the Nature Conservancy in its recently published comprehensive assessment of California’s freshwater ecosystems
A 2014 center study by Ted Grantham and co-researchers Joshua Viers and Peter Moyle is a good example of how PISCES can be used.
The scientists found PISCES invaluable for quantifying the impacts of individual dams on California’s native fishes. They needed to know with good precision the current and former ranges of imperiled species in relation to dams. This information in turn can be used to determine which dams would provide the most benefit to native fishes with improved flow releases.
PISCES enabled the researchers to flag dams in drainages known to support salmon, lamprey, splittail and other species sensitive to unnatural changes in flows. Using this filter and several others, they evaluated 753 dams on relatively large streams and rivers and identified 181 of them – 25 percent – as high-priority candidates for enforcement, under a law requiring dam owners to release enough flow “at all times” to keep fish “in good condition.”
For Moyle, a UC Davis professor emeritus of fish biology, PISCES is the culmination of several efforts to aggregate and digitize scientists’ scattered field notes and databases on locations of California fishes.
Moyle made his first attempt in the mid-1980s, to inform state fish and game wardens of the fishes likely to be affected by proposed stream alterations. He and then-graduate student Paul Randall conducted a more sophisticated cataloguing and mapping of native fish ranges in the mid-1990s as part of the Sierra Nevada Ecosystem Project, a sweeping scientific study benchmarking the ecological health of the 400-mile-long mountain range.
However, none of these efforts gained traction beyond the specific projects.
The turning point came in 2011. The U.S. Forest Service issued a solicitation for accurate maps of fish species locations on California’s national forests, which cover one-fifth of the state. Moyle, Viers, and graduate student Jacob Katz saw an opportunity to develop a comprehensive database.
A team of center scientists and computer programmers embarked on an extensive literature search for empirical and inferred observations of fish locations. In many cases, though, the information was stored in the unwritten memories of veteran biologists like Moyle. Researchers spent countless hours interviewing experts and poring over maps. By 2014, the group had collected 274,555 records documenting the range of California fish species.
As open-source software, PISCES allows users to enhance the tools and software and propose updates and corrections on the data. The data are available in many standard spatial and relational forms accessible from ArcGIS, QGIS, Google Earth, Microsoft Access and other software.
Although PISCES is focused on California fish, the software and database are a generalized system for tracking and analyzing ranges. It can be quickly adapted to track fauna anywhere. Scientists can install and use the software to tweak their own species ranges, export data into other formats, generate custom range maps or create ones for whole new areas or species.
Moyle said he can live easier knowing that his four decades of memories on species locations in California can be easily downloaded from a website.
“The future won’t have to rely my foggy recollections and penciled field notes,” he said. “You’ll have the database.”
Nick Santos creates geospatial applications for the UC Davis Center for Watershed Sciences and developed the PISCES software.