Science Spotlight

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  • April 25, 2017

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.

A photo of the world’s first radio tagged tricolored blackbird (Agelaius tricolor) graces the cover of this issue of California Fish and Game. The bird was tagged as part of a study, the results of which are published as “Breeding chronology, movements, and life history observations of tricolored blackbirds in the California Central Coast” by Wilson et al. The tricolored blackbird is currently under review for listing under both the California and Federal endangered species acts.

Also in this issue, Overton et al. offers a fascinating observation of predation by Peregrine falcons on an endangered California Ridgway’s rail (Rallus obsoletus obsoletus), the result of environmental extremes and a series of species interactions.

Other papers published in this issue look at a predictive model for commercial catch of white seabass (Atractoscion nobilis); fecundity and reproductive potential of wild female Delta Smelt (Hypomesus transpacificus); and updated information on the length-weight relationships (LWR) and length-length relationships (LLR) and condition factors for pelican barracuda (Sphyraena idiastes) in the Gulf of California.

New in this issue is a section called “From the Archives,” which reprints articles from past issues to provide historical perspective on topics still relevant today. The first article in this series comes from Volume I, Issue I, dated 1914. It asserts that natural resources must be conserved for the use and enjoyment of the public.

Download the entire Fall Issue 102 in high resolution, or browse individual articles in low resolution.

Categories: California Fish and Game Journal
  • April 18, 2017

California hosts approximately 6,500 different kinds of plants that occur naturally in the state, and many of these are found nowhere else in the world. Some of these plants are so rare or have been so impacted by human influence that they are at risk of permanent extinction from the wild and have been protected by state and federal laws. The California Department of Fish and Wildlife’s (CDFW) Native Plant Program is developing and implementing standardized and repeatable monitoring plans for ten state and federally listed plant species on nine CDFW Ecological Reserves throughout the state. This work is funded by a federal grant awarded in 2015.

a man kneels to look at wildflowers

One of the plants being monitored is Butte County meadowfoam (Limnanthes floccosa ssp. californica), which occurs at North Table Mountain Ecological Reserve, north of Oroville in Butte County. The reserve is on an elevated basalt mesa that was created by ancient lava flows and supports a rare type of vernal pool called Northern Basalt Flow Vernal Pools. There were only 498 Butte County meadowfoam plants found on the reserve this spring. The reserve also supports a high diversity of other plant species that erupt with bright colors in the spring and attract hordes of visitors.

Another plant being monitored is the endangered Slender-petaled thelypodium (Thelypodium stenopetalum) that occurs at Baldwin Lake Ecological Reserve, in the San Bernardino Mountains near Big Bear. The reserve is in a unique environment known as the pebble plains, which only occur in Big Bear Valley and nearby Holcomb Valley. The pebble plains were formed when glaciers receded during the Pleistocene age and mainly consist of clay soils overlain by a layer of orange and white quartzite pebbles. Slender-petaled thelypodium only grows in this rare pebble plain habitat, and only 15 plants were found on the reserve last spring. Other rare plant species such as the endangered bird-foot checkerbloom (Sidalcea pedata) are found on the reserve and in the surrounding pebble plain habitat.

The monitoring project also includes plants at Little Red Mountain, Boggs Lake, Loch Lomond, Stone Ridge, Phoenix Field, Pine Hill and Apricum Hill Ecological Reserves. The grant is funded through January 2018 and the Native Plant Program has applied for another grant to continue this project.

Categories: General
  • April 11, 2017

Two men capture an elk on grassy hill
Three men fit a research collar on a tule elk
Eight-man stand in front of a red helicopter

The California Department of Fish and Wildlife (CDFW) recently launched the first phase of a multi-year study of tule elk in Colusa and Lake counties. In partnership with the University of California, Davis and the Rocky Mountain Elk Foundation, and with the assistance of capture specialists from Leading Edge Aviation, researchers used helicopter net guns to capture and place satellite collars on 45 tule elk.

The technique of using DNA extracted from fecal pellets to study wildlife populations is a relatively new, non-invasive approach that minimally disturbs animals and enables surveys in low-visibility habitats where sight-based surveys would be relatively ineffective. It is also less costly than other survey methods, and therefore can be used more frequently.

While fecal DNA analysis has been used to estimate abundance and other population parameters in deer herds in California since 2011, this study will be the first application of the technique to free-ranging tule elk. The study results will guide future elk conservation planning efforts.

Tule elk are a native subspecies of elk unique to California. Prior to the arrival of European settlers, they numbered more than half a million statewide, but the population rapidly declined in the mid-1800s due to unregulated market hunting and habitat loss. In 1875, a ranch owner in Kern County took efforts to protect the last remaining tule elk and allowed them to multiply on his property, likely saving them from extirpation.

Since 1975, CDFW has captured and relocated more than 1,500 elk. As a result, there are an estimated 5,100-plus tule elk distributed in 22 herds throughout California today. See more information about the distribution, range and history of this unique animal in California.

Categories: Wildlife Research
  • April 6, 2017

Two women in lab coats simulate oiled bird intake
Three tan tents set up in campground

About 10 environmental scientists from CDFW’s Office of Spill Prevention and Response (OSPR) participated in a large-scale oil spill drill along the Feather River on March 21. The drill was intended to help wildlife response teams prepare for a potential train derailment. OSPR has a long history of oil spill response in marine environments but recently expanded its scope statewide to include inland waters. This Feather River exercise was the first time a substantial wildlife response drill has been held inland, testing responders’ abilities to resolve many operational and technical issues presented by a river spill.

Whereas marine spills typically require rescue of seabirds and occasionally marine mammals, the kinds of animals potentially affected by inland spills are quite different and varied, potentially including raptors, songbirds, reptiles, amphibians, rodents, foxes, and other mammals. The need to capture and care for these species during an oil spill presents unique challenges for scientist responders. The goal is to have the necessary protocols in place and practiced.

The drill was put on by the California Oiled Wildlife Care Network (OWCN), an organization funded by OSPR and managed by the UC Davis School of Veterinary Medicine to provide best achievable care of oiled wildlife. The OWCN currently maintains a network of 40 wildlife rehabilitation organizations, trained and ready to respond to oil spills anywhere in the state. Sixteen of these organizations participated in Tuesday’s drill, including two local organizations, Shasta Wildlife Rescue and Rehabilitation and North Valley Animal Disaster Group.

In addition to practicing wildlife response activities, the drill provided the opportunity to test a new Geographic Response Plan (GRP) for the Feather River. GRPs identify the location and nature of resources at risk in the event of a spill, and outline appropriate tactical response strategies to minimize oiling and other injury. During a real spill, OSPR environmental scientists serve as subject-matter experts who help ensure that the GRP is implemented appropriately. A simulated situation like this one gives them a valuable opportunity to conduct a realistic ‘dry run,’ as well as to analyze elements of the GRP and make adjustments as necessary.

To learn more about OSPR, visit www.wildlife.ca.gov/OSPR.

Categories: General