Science Spotlight

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  • January 13, 2022

The California Fish and Wildlife Journal concludes its 2021 Special Issue installments with the winter quarter’s Special Issue: Effects of Human-Wildlife Interactions on California’s Natural Resources: Conflict and Coexistence (PDF). With this year’s unprecedented drought, unpredictable fire season, climate change, pandemic response, and increased human-wildlife conflict reported statewide, issue 107-3 is salient and timely. In this Special Issue, we explore various interconnected themes across four sections: Terrestrial Predator Interactions, Conflicts & Adaptive Management, Coexistence & Conservation, and the Human Dimensions of Wildlife Conservation.

cover of Journal showing fox, with city in background

The California Department of Fish and Wildlife (CDFW) serves as the lead state agency charged with helping to resolve human-wildlife conflict, public safety, and reported depredation (property damage) and committed to advancing discussion and deeper understanding of human-wildlife interactions throughout the state. People live increasingly in close contact with animals, both wild and domestic, as the human population expands along the wildland-urban interface and increases over time. This reality has led to increased human-wildlife interactions and reported  human-wildlife conflict. Negative human-wildlife interactions can directly affect human and wildlife health and may result in loss of livelihood, reduced wellbeing, or in some instances, loss of life – animal or human.

Come read about the various types of human-wildlife interaction, some of the unique challenges – and opportunity – to better address understand and address human-wildlife conflict. Various agency partners, practitioners, researchers, and key stakeholders have contributed their expertise to this Special Issue. We hope you recognize the myriad factors that can shape our perception and approach to wildlife in California. Learn more!

The California Fish and Wildlife Journal has published high-quality, peer-reviewed science for more than 100 years – and the CDFW looks forward to more valuable contributions ahead.

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Categories: California Fish and Game Journal, Science Spotlight
  • December 9, 2021
Bird on a tree branch

California is home to more native animal and plant species than any other state in the nation. It also hosts the most endemic species—species that occur nowhere else in the world. However, our incredibly diverse native wildlife is facing an intensifying array of stressors stemming from human activity: habitat loss, new land uses like cannabis cultivation, invasive species, wildfires, drought and so many others. Wildlife managers can mitigate these threats through actions like conserving and restoring habitat, building relationships with private landowners and managing ecosystems for resilience to wildfire and climate change. But, to effectively target management actions, managers need to have high-quality information on wildlife populations across the state.

In two studies recently published in the California Fish and Wildlife Journal, Vol. 107-2 (PDF), researchers with CDFW’s Cannabis Program and Wildlife Diversity Program focused on this need for effective wildlife data collection.

One study focused on monitoring small terrestrial vertebrates, like small mammals, reptiles and amphibians. Traditionally, researchers have monitored these species through live-trapping and visual encounter surveys. But such time-intensive methods are not always feasible. Recently developed methods that use automatic cameras are one alternative. To determine how well cameras perform compared to more traditional methods, CDFW researchers tested two methods alongside each other: 1) visual encounter surveys, where they searched for reptiles and amphibians in a study area, and 2) camera traps, which combined small strips of fencing with close-focus cameras pointed at the ground. They found that the camera system detected far more species of small animals compared to the traditional surveys.

In a second study, researchers compared different methods for monitoring birds. Traditionally, researchers have used point counts, where trained observers identify every bird they hear or see at a location. Researchers are also increasingly using acoustic devices to automatically record bird sounds. Recently, machine learning tools have enabled computers to identify bird sounds from these recordings, allowing people to indirectly identify birds while saving much time and effort. In their study, the CDFW researchers found that low-cost recorders performed comparably to expensive ones, and that a machine learning tool accurately identified high numbers of bird species from the recordings.

The researchers will apply what they have learned and shared to a new statewide monitoring effort, which is being developed by CDFW’s Cannabis Program. These advancements will enable a more efficient wildlife monitoring effort that saves money and time. And most importantly, with the information gained from improved monitoring, CDFW staff and other wildlife managers will be able to make more informed decisions to help our native California wildlife cope with current and future challenges.

Categories: California Fish and Game Journal, General, Science Spotlight
  • November 12, 2021
journal cover featuring mouse balanced atop grain stock

Since being signed into law in 1970, the California Endangered Species Act, or CESA, has proved to be a landmark law in a history of progressive wildlife conservation in California. It has been key in helping to stem the tide of species extinctions, raise public awareness about the plight of wildlife, and underscore the need to balance species conservation with economic development. CDFW is responsible for safeguarding the hundreds of CESA-listed species, and a key part of this mission is supporting and elevating the important research being conducted on these imperiled plants and animals.

The 2021 Special Issue of the California Fish and Wildlife Journal titled “The California Endangered Species Act: Successes and Challenges” contains a comprehensive collection of articles about the research, management and conservation of threatened and endangered species. At 473 pages, this is the largest Journal issue ever published! It includes 16 full research articles, five research notes, two review papers and four essays, altogether covering 25 species. Authors include CDFW staff, academic researchers, non-profit organizations and other conservation entities. Download the entire issue (PDF) or individual articles.

Topics covered in the issue include range expansions, new methods for species identification in the field and lab, reviews of habitat use and spatial occurrence patterns throughout California, results of management actions, benefits of long-term monitoring programs and planning strategies for conservation and recovery actions. The issue starts with a CESA Policy and Regulations section and follows with eight sections organized by taxa. Photos at the beginning of each section showcase California’s amazing biodiversity. For those new to CESA, an overview of the listing process is provided both in a detailed article and a simplified flowchart.

Article highlights include:

Amargosa Niterwort

Plants make up 158 of the 316 species currently listed under CESA. In this issue, Amargosa niterwort (Nitrophila mohavensis) takes the spotlight when authors share the value of a 10-year monitoring program for this alkali wetland plant, which occupies a total area less than 20 km2 in the northern Mojave Desert. Collaborative monitoring has resulted in a better understanding of the species, including phenology and abundance trends. This information could support conservation actions in response to threats such as groundwater alteration and off-highway vehicle impacts. For more details, see the article titled “Status of the Amargosa niterwort (Amaranthaceae) in California and Nevada.”

Bumble Bee Protection

In the article “A conservation conundrum: protecting bumble bees under the California Endangered Species Act,” authors Richard Hatfield and Sarina Jepson of the Xerces Society for Invertebrate Conservation present their view of the history and recent context of listing invertebrates under CESA. The authors argue that population declines driven by factors including climate change, insecticides and habitat loss have led to thirty percent of California’s bumblebee species facing extinction risk. In light of this, the Xerces Society and others have led a recent push to provide formal protections for several species of bumblebee. The article provides the authors’ overview of their 2018 petition to protect four imperiled bumblebee species under CESA and the subsequent legal complications that have unfolded.

California Tiger Salamander

“Use of atypical aquatic breeding habitat by the California Tiger Salamander” provides insight into this endangered species’ ability to reproduce outside of its historically associated habitat. Typically thought to reproduce only in vernal pools, researchers observed California tiger salamanders breeding in cattle stock ponds, intermittent creeks and rain-filled excavated depressions. Further investigation is needed to determine if these atypical breeding sites result in any reproductive success, as some have limited hydroperiods that may not be conducive to California tiger salamander metamorphosis. However, this study provides insight for the potential role of reproductive plasticity in the face of vernal pool habitat loss. For development projects within the range of the California tiger salamander, this study identifies additional habitat features that should be assessed when identifying and addressing potential impacts to this listed species.

We would like to thank the CDFW editorial staff for their hard work on this special issue. We also want to thank and acknowledge the researchers and authors of the articles, whose hard work to understand these imperiled species is helping bring them closer to recovery. The California Fish and Wildlife scientific journal has published high-quality, peer-reviewed science that contributes to the understanding and conservation of California’s wildlife for more than 100 years. We look forward to the continued contributions in the next decade to come.

Categories: California Fish and Game Journal, Science Spotlight
  • January 5, 2021

The link opens in new windowCalifornia Fish and Wildlife Journal concludes the 2020 Special Issue installments with the winter quarter’s Special Wildland Fire Issue. With this year’s unprecedented fire season, and California’s fire-adapted natural communities taking center stage in land management discussions throughout the State and beyond, this issue is especially poignant as we reflect on this past year and contemplate the incoming new year.

Unlike previous Special Issues, this issue is divided into three sections: Vegetation Treatment and Policy, Fire Impacts on Plants, and Fire Impacts on Wildlife and Water. Each section highlights a piece of the wildfire and landscape management ‘puzzle’ through an examination of fire and its impacts on California’s fire-adapted ecological landscape.

One of these unique communities, the Pine Hill Ecological Reserve in El Dorado County, is home to almost 750 plant species, some of which can only be found at Pine Hill due to its unique soil composition. Researchers from CDFW, the California Native Plant Society and Sacramento City College investigate the impacts of different fuel-reduction methods on Pine Hill Ceanothus in link opens in new window“Effects of a firebreak on plants and wildlife at Pine Hill, a biodiversity hotspot, El Dorado County, California” (PDF). The article examines the effects of hand clearing and pile burning on chaparral species within the Wildland Urban Interface and the secondary impacts on wildlife. The study also includes the exciting discovery of new seedlings of Pine Hill Flannelbush, the rarest and most endangered plant in El Dorado county, and a fire-obligate germinator!

Plants that depend on fire to propagate aren’t the only plant communities impacted by the long-term fire suppression practiced in the western United States. New and updated technology is helping landscape managers and scientists study and assess the pre- and post-fire impacts to landscapes using remote sensing and modeling techniques. This type of data collection and analysis helps inform scientists and policy makers on landscape and watershed-level scales and helps focus efforts to manage habitats and sensitive plant communities before and after wildfires. One such effort is presented by Sonoma County scientists in link opens in new window“Sonoma County Complex Fires of 2017: Remote sensing data and modeling to support ecosystem and community resiliency” (PDF). With the help of NASA and other experts the team evaluates the impacts of the 2017 fires to woody vegetation within areas that burned during wind-driven and non-wind driven events to evaluate canopy condition. Using lidar data, the team identifies important predictors for post-fire woody canopy condition, which highlights the importance of high-resolution airborne mapping technology for informing management decisions.

Management decisions include when and how to monitor pre- and post-fire events, and the CSU Monterey Bay’s study link opens in new window“Analysis of the impacts of the Soberanes Wildlife on stream ecosystems” (PDF) highlights the need for monitoring wildfire’s impacts on coastal streams and benthic macroinvertebrate responses to fire events. This monitoring is especially important because macroinvertebrates are the foundation for in-stream salmon and steelhead foodwebs, and the ability of these microscopic organisms to recover from wildfire also impacts the recovery of these keystone species in California’s rivers and streams.

This quarter’s Special Wildlife Fire Issue also includes examinations of impacts and responses of Roosevelt Elk forage in Humboldt County, an essay on the California Vegetation Treatment Program, amphibian responses to wildfire and other topics that span California’s rich ecological diversity.

The California Fish and Wildlife scientific journal has published high-quality, peer-reviewed science that contributes to the understanding and conservation of California’s wildlife for more than 100 years. We look forward to the continued contributions in the next decade to come.

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Media Contact:
Kirsten Macintyre, CDFW Communications, (916) 804-1714

Categories: California Fish and Game Journal, Science Spotlight
  • April 2, 2019

The latest issue of California Fish and Game, Vol. 105, Issue 1 (PDF), focuses on marine species, bringing new insights and understanding of several fish species found off the California coast.

In A very long term tag recovery of a California scorpionfish (Scorpaena guttata) (PDF), Roberts and Hanan report the remarkable recovery of a tagged scorpionfish that had been at liberty far longer than any previously recaptured scorpionfish. The recovery was made during a four-year mark-recapture study on nearshore groundfish off southern and central California. More than 32,000 fish were recaptured, with an average of 408.8 days at liberty. The study results indicate that scorpionfish demonstrate strong site fidelity, given that a majority of the fish were recaptured within 5k of their original tagging site. The scorpionfish that is the subject of the article was tagged in 2004. It had been at liberty for nearly 14 years (5,048 days). After removing the tag, the fisherman who captured the fish reported that he released it “unharmed and looking very healthy.”

Another paper reports on a method for estimating the age of roosterfish using dorsal fin spines (PDF). According to authors Chavez-Arellano et. al, the roosterfish is considered a prized species by the sport fishing community and provides a significant economic benefit to the Mexican tourism industry. However, little is known about its biology, ecology, and movement patterns. The authors embarked upon a study to assess which sections of roosterfish dorsal fin spines have the most legible indicators of growth for use in future aging studies. Their work provides the initial basis from which future aging studies can be conducted.

Finally,Primary and secondary nursery areas for leopard and brown smoothhound sharks in San Francisco Bay, California (PDF), summarizes a 31-year study to determine primary and secondary nursery habitats for leopard and brown smoothhound sharks within South San Francisco Bay, adding new knowledge to the biology of both species.

As it has for the past 105 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.

CDFW Photo.
Media Contact:
Lorna Bernard, CDFW Communications, (916) 322-8911  

Categories: California Fish and Game Journal
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