Science Spotlight

California Fish and Game, Volume 104, Issue 2, is now available online! California Fish and Game is CDFW's official, quarterly, scientific journal devoted to the conservation and understanding of the flora and fauna of California and surrounding areas, and the eastern Pacific Ocean.

A mallard in flight appears on the cover of the newest installment of the journal. With its iridescent green head and school bus yellow legs, the male mallard is one of the most recognizable species of duck in California. It is also the most abundant breeding species of waterfowl in the state. However, California’s mallard population estimates have generally declined since the mid-1990s. In California mallards: a review, Feldheim et. al synthesizes volumes of research in an effort to identify long-term research needs and monitoring activities to help improve management of this iconic species.

In another paper, entitled Abundance, habitat and occupancy of Roosevelt Elk in the Bald Hills of Redwood National Park, Tolliver and Weckerly seek to understand the relationship between a species’ occupancy-abundance rate and its habitat use. Using elk sign surveys (i.e, counting tracks and feces at standardized locations) researchers found that, as population density increases, Roosevelt elk will move into other (lower quality) habitats. This was true for two herds of vastly different sizes, although the occupancy rate remained comparable.

Finally, Hiney et. al looks at recruiting experienced anglers and using citizen science to help document and survey the native Coastal Rainbow Trout population of Grass Valley Creek Reservoir. The authors look at methods of overcoming the time and resource limitations of assessing wild trout populations.

Also included in this issue are reviews of two books that make meaningful contributions to the field of wildlife research.

As it has for the past 104 years, California Fish and Game continues to publish high-quality, peer-reviewed science that contributes to the understanding and conservation of California’s wildlife. We look forward to witnessing the contributions of the next installment.

The latest issue of California Fish and Game, CDFW’s scientific journal, is now available online. This century-old quarterly journal contains peer-reviewed scientific literature that explores and advances the conservation and understanding of California’s flora and fauna.

The endangered salt marsh harvest mouse (Reithrodontomys raviventris) graces the cover of California Fish and Game, Volume 103, Issue I. Researchers ventured into the pickleweed to study the tiny mouse, which is endemic to the marshes surrounding the San Francisco Estuary Bay and its tributaries. The mice were fitted with tiny radiotelemetry collars and tracked for three years. Researchers documented some curious behavior in the resulting paper, “Potential evidence of communal nesting, mate guarding, or biparental care.” The accompanying photos provide a fascinating glimpse into an active nest.

Another paper, “Documentation of mountain lion occurrence and reproduction in the Sacramento Valley of California,” explores the potential for mountain lions to exist in fragmented habitats if there is adequate connectivity with larger blocks of suitable habitat and sufficient prey. The study used camera traps to document populations of mountain lions in the Sacramento Valley’s Butte Sink, which is made up of relic riparian habitats interspersed with managed wetlands. The photos show healthy mountain lions moving through habitat that has long been considered unsuitable due to extensive agricultural and urban development.

The article, “Mussels of the Upper Klamath River, Oregon and California,” reports on sampling efforts that expand existing baseline population data on freshwater mussels in the Upper Klamath River. The sampling efforts may ultimately assist with protection, mitigation and enhancement efforts for large bi-valve species.

The final paper provides insights into the benefits deer and elk derive from licking mineral rocks. Researchers took samples of “lick sites” that were used by California black-tail deer (Odocoileus hemionus columbianus) and Roosevelt elk (Cervus canadensis roosevelti) in the Klamath Mountains, Siskiyou County. After performing a detailed analysis of the elemental content of each lick site, the researchers concluded that each lick site offers a different smorgasbord of minerals, and in varying concentrations. The study’s objective is to begin identifying, classifying, and analyzing important mineral lick sites to benefit future ungulate management efforts.

As it has for the past 103 years, California Fish and Game continues to publish high-quality, peer-reviewed science that contributes to the understanding and conservation of California’s wildlife. We look forward to witnessing the contributions of the next installment.

Download the entire Winter Issue 103 (PDF) in high resolution, or browse individual articles in low resolution.