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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 ...

• 2018 Waterfowl Breeding Population Survey Shows Continuing Upward Trend

  

  The California Department of Fish and Wildlife (CDFW) has completed its 2018 waterfowl breeding population survey -- and it’s good news for hunters and birdwatchers alike, as the total waterfowl population in the state now tops out at over a half million, for the first time in six years. Melanie Weaver, who oversees CDFW’s Waterfowl Program, said that duck populations responded positively to the wet winter conditions of 2017. “Given the good upland and wetland habitat conditions last year from excessive precipitation, we anticipated good production,” she said. “We are pleased to see that higher recruitment reflected in this year’s breeding population survey.” The full Breeding Population Survey Report, which can be found on the CDFW website, indicates the 2018 breeding population of mallards increased from 198,392 in 2017 to 272,859 (an increase of 38 percent). Mallards are the most abundant waterfowl species in the state, followed by gadwall (102,637) and cinnamon teal (78,498). Other ducks that increased in number include northern shovelers, wood ducks, redhead and canvasback. Overall, the total number of ducks increased from 396,529 to 549,180 (an increase of ...

• 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 Pilot Study Establishing Foundation for Enhanced Study of Porcupines

  

  Porcupine1: NRVP participants Greg Moore, Mike Maulhardt, Charles Brown and Ben Smith volunteered to service and maintain porcupine stations at Red Lake Wildlife Area. Not to put too fine a point on it, but studying California’s porcupines hasn’t traditionally been a high priority for CDFW. Wildlife research funding is limited, especially for non-game species, and species listed as threatened or endangered are typically given top priority. That means that scientists sometimes need to be creative – and frugal – in their efforts to survey and manage non-listed, non-game species. Stacy Anderson, a CDFW senior environmental scientist specialist based in Rancho Cordova, recently conducted a pilot project that does just that. Anderson developed an interest in the North American porcupine (Erethizon dorsatum) in 2017, after acknowledging that anecdotal evidence seems to indicate their numbers are on the decline. Porcupines have historically inhabited diverse habitats including Humboldt County, along the Sacramento River, in the Coast Ranges, the Klamath Mountains, the southern Cascades, the Modoc Plateau and the Sierra Nevada. But in her conversations with unit biologists and wildlife officers in some of these areas, ...

• CDFW Gets a Jump on Preserving Sierra Nevada Yellow-legged Frogs

  

  It does not take a leap of faith to believe that CDFW scientists have gained the upper hand in bolstering the population of yellow-legged frogs in the High Sierra. Over the past three decades, Sierra Nevada yellow-legged frogs have become imperiled in California due to the two-pronged impact of introduced (non-native) trout and chytridiomycosis, a disease that is affecting amphibians worldwide. Past introduction of non-native fish, including rainbow trout and golden trout, to benefit sport fishing in the High Sierra took a heavy toll on the species. High-elevation lakes where these frogs once flourished were largely fishless until fish stocking came into vogue. As the years passed, scientists determined that these introduced fish were depopulating the frogs by competing for food sources (primarily insects) and by predation (trout ate both adult frogs and their tadpoles). Chytridiomycosis, which affects many frog species, also impaired the ability of the Sierra Nevada yellow-legged frog’s skin to exchange vital nutrients, which often leads to death. As a result, Sierra Nevada yellow-legged frogs are believed to have vanished from approximately 92 percent of their historical ...

• 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. ...