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• CDFW Completes 2017 Waterfowl Breeding Population Survey

  

  The California Department of Fish and Wildlife (CDFW) has completed its annual waterfowl breeding population survey. Mallards, gadwall and cinnamon teal comprised 54 percent of the ducks observed, down 30 percent from last year. The number of mallards decreased from 263,774 to 198,392 (a decrease of 25 percent) and total ducks decreased from 417,791 to 396,529 (a decrease of five percent). The most notable decrease occurred in the Sacramento Valley area, where mallards were estimated at a record low of 31,000 (73 percent below the long-term average). Given the abundant precipitation, one might expect the numbers to be higher. In some parts of the state, it did indeed increase available habitat (uplands and ponds). But in many areas, last winter’s heavy rains largely resulted in deep, fast-flowing water, which is not ideal for dabbling ducks. Other reasons for low duck observations could include winter flooding of nesting habitat that normally remains dry, the late-season flooding of the rice fields in the Sacramento Valley and the conversion of rice fields and pastures to tree crops. CDFW biologists and warden pilots have conducted this annual ...

• Survey Says: California Marine Anglers Help Scientists Collect Data

  

  If you’re an avid marine sport angler, you have most likely seen the smiling faces and brown polo shirts of California Recreational Fisheries Survey (CRFS) samplers. Since its inception in 2004, CRFS has grown into one of the state’s largest and most important survey efforts. Survey samplers are tasked with collecting data about both recreational fishing catch and effort. Annually, CRFS samplers make direct contact with 68,000 fishing parties at over 400 sampling sites between the California-Oregon state line to the California-Mexico border. A separate but related telephone survey effort contacts an additional 26,000 anglers. A program of this large scale is necessary because recreational fishing effort and success rates are highly dynamic – a large sample size is needed to adequately estimate catch and effort. Recreational fishing effort is also very challenging to predict, as it can be affected by many factors (weather, gas prices, time of year, fishing seasons, etc.). But the recreational sector accounts for a significant portion of overall marine harvest, so it’s essential to collect that data to produce reliable estimates of harvest. CRFS is ...

• CDFW and Oregon State University Researchers Estimate the Population Size of Fishers in Northern California and Southern Oregon

  

  Scientists with the California Department of Fish and Wildlife (CDFW) and Oregon State University recently published the results of a population study on fishers (Pekania pennanti) in northern California and southern Oregon. Led by CDFW Wildlife Statistician Dr. Brett Furnas and three coauthors, CDFW Senior Environmental Scientist Richard Callas, CDFW Research Analyst Russ Landers and Dr. Sean Matthews of Oregon State University, the study produced the first-ever robust estimates of density and size of the fisher population in northern California. “This is the first time we’ve come up with a solid number of fishers, which is a starting point for tracking and monitoring populations,” Furnas said. “One of the most important tools we have used so far to help this species is reintroductions, so now -- with a baseline established and ongoing surveys planned -- we’ll be able to see if the population is really rebounding over time.” Fishers in northern California and southern Oregon represent the largest remaining population in the Pacific states. The species once ranged from the state of Washington southward through Oregon and California. ...

• CDFW Kelp Survey

  

  Beneath the waters off the California coast are vast forests that are home to an astounding variety of animals. Their sunlit canopies can soar 150 feet from the ocean’s floor. But instead of trees, these forests are made of kelp. Worldwide, kelp is used in a host of everyday products like toothpaste, pudding, ice cream and even pharmaceuticals. Although kelp is valuable to humans, it is critical to sustaining life for many ocean-dwelling wildlife species ranging from microscopic plankton to sea otters, pelagic birds and predatory fishes. When a kelp forest is depleted, the entire underwater ecosystem can be thrown out of balance. This is why CDFW scientists are tracking and studying the amount of kelp growing in coastal waters. In 1989, CDFW marine biologists began using aerial surveys to monitor the size of the kelp forests off of California’s coast. A second survey was conducted a decade later, and since 2002, CDFW has made an effort to conduct these surveys annually (although budget issues sometimes require skipping a year). The surveys are conducted along the entire coastline and offshore of ...

• Counting Lizards: New CDFW Study Confirms a Better Way to Survey Reptiles

  

  CDFW scientists conducted a groundbreaking survey of lizards across the entire Mojave Desert. CDFW graphic. One might say that a groundbreaking new study conducted by two CDFW scientists and their research partners provides a leap forward in lizard research. Dr. Brett Furnas, a senior environmental scientist with CDFW’s Wildlife Investigations Lab, is the lead author on a paper entitled Hierarchical distance sampling to estimate population sizes of common lizards across a desert ecoregion. The co-authors on this paper are Scott Newton and Griffin Capehart, both formerly contractors for the Wildlife Branch at CDFW, and Dr. Cameron Barrows with the Center for Conservation Biology at the University of California, Riverside. According to Furnas, monitoring programs that survey many wildlife species at the same time across large geographic regions are important for informing conservation decisions, but reptiles are often missing from these efforts because they are difficult to survey. Therefore, the researchers applied a new distance-sampling approach to more accurately count lizards across the entire Mojave Desert within California (25,803 square miles in total). “As far as we know, this is the first time a ...

• Science Spotlight: Legwork and Expertise Combine to Bolster Endangered Frog Populations

  

  Yellow-Legged Frog Mountain Yellow-Legged Frog habitat Many years of painstaking monitoring and assessment efforts undertaken by CDFW have helped guide an ongoing effort to bolster the dwindling populations of mountain yellow-legged frogs in Southern California. Tim Hovey, a senior environmental scientist in CDFW’s South Coast Region, has been hiking through the forest to monitor and evaluate yellow-legged frogs in Little Rock Creek and Big Rock Creek in the Angeles National Forest since 2002, when they were listed under the Endangered Species Act (they were listed as state endangered in 2013). At that time, it was estimated that fewer than 100 adult frogs remained in the wild.  The drastic decline of this population over the last 50 years has been a cause for concern to biologists. “The mountain yellow-legged frog is a critical part of the fragile stream ecosystem here in Southern California,” Hovey explains. “We hope that our efforts to increase the wild population through captive tadpole release will eventually lead to self-sustaining populations that will no longer require captive care to recover.”   Hovey estimates that fewer than 400 adult mountain yellow-legged frogs ...