Geology topics
J. P. Fleskes
Publications and source records attributed to J. P. Fleskes.
Waterfowl Distribution, Movements and Habitat Use Relative to Recent Habitat Changes in the Central Valley of California: Progress Report - June 2000
No abstract available at this time
Ecology of female northern pintails during winter in the San Joaquin Valley, California
No abstract available at this time
Changing patterns of goose harvest on California public hunting areas
We summarized hunter visits, success, and the magnitude and species-subspecies composition of tho goose harvest recorded on California public hunting areas (PHAs) during 1950-89. Of six geographic regions, the Northeast accounted for the largest portion of the PHA harvest (55%); most of the remainder occurred in the Sacramento (30%) and Imperial (10%) Valley regions. Harvest, hunter visits, and success were low during the 1950s, but increased during the 1960s as new PHAs were added and data from Tule Lake and Lower Klamath National Wildlife Refuges (NWRs), where about half of California's PHA goose harvest occurs, became available. Success and harvest reflected declining goose abundance during the 1970s; however, hunter visits remained high on most PHAs because ducks were abundant. During the 1980s, declining populations of greater white-fronted geese, Anser albifrons frontalis, and cackling Canada geese, Branta canadensis minima, prompted restrictive regulations resulting in low harvest and success. Hunter visits were further reduced because of declining duck abundance and overall declines in hunter numbers. White-fronted geese were most prominent in the Northeast and Suisun Marsh harvest, but the lesser snow goose, Chen caerulescens caerulescens, was more important in other regions. Overall, the cackling Canada goose was the third most common goose harvested. The harvest of most geese peaked during 1965-74, coinciding with a peak in hunter visits, and then declined. However, the harvest of Canada geese (includes unknown proportions of western, B. c. moffitti, Taverner's, B. c. taverneri, and lesser, B. c. parvipes) and Ross' geese, Chen rossi, increased slightly throughout the study period. PHA harvest averaged 9-15% of the total state goose harvest during 1960-89. Success on PHAs was greater than statewide success until the 1980's, when restrictive regulations were imposed in zones encompassing many Sacramento Valley and San Joaquin Basin PHAs. White-fronted geese comprised a larger portion of the PHA bag than state-wide, and their decline reduced hunting opportunity for PHA hunters. The status of Pacific Flyway geese has improved in recent years, but intensive population management and monitoring should continue.
Changing patterns of goose harvest on California public hunting areas
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Remains of ducks and other prey found near fox and mink dens on an Iowa Wildlife Refuge
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Survival, movements, and habitat use of juvenile and adult female northern pintails in the San Joaquin Valley. Progress Report
No abstract available at this time
Record of a redhead, Aythya americana, laying eggs in a northern harrier, Circus cyaneus, nest
An active Northern Harrier, Circus cyaneus, nest containing Redhead, Aythya americana, eggs, found in an Alberta wetland, apparently represents the first record of a Redhead parasitizing a harrier.
Survival and other observations of adult female northern pintails molting in California
Survival rates of nine adult female Northern Pintails (Anas acuta) that became flightless after being radio-marked in the Sacramento Valley, California in August 1987-1989 were estimated. Seven of the radio-marked pintails molted in the Sacramento Valley, a nontraditional molting region, and two flew 280 km north to the Klamath Basin to molt. Molting marshes were dominated by emergent vegetation in both locations. Two ducks, while flightless in the Sacramento Valley, were killed by predators. Molting pintails remained sedentary (did not fly) for an average of 36 d, and the daily survival rate during this period was 0.9934. The resulting sedentary-period survival rate was 0.79. Primary feather 9 on two captive ducks grew an average of 4.2 mm per day. Mean body mass of molting ducks that died was lower than that for molting ducks that survived (P < 0.10). The number of pintails molting on Sacramento Valley refuges is probably <200.
Record of a redhead, Aytha americana, laying eggs in a northern harrier, Circus cyaneus, nest
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Survival and other observations of adult female northern pintails molting in California
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A simplified detonator for rocket net traps
No abstract available at this time
Survival, movements, and habitat use of juvenile and adult female northern pintails in the San Joaquin Valley. Progress Report
No abstract available at this time
Two incubating mallards move eggs to drier nest sites
Abstract has not been submitted
Two Incubating mallards move eggs to drier nest sites
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High survival rates for female northern pintails in California's Sacramento Valley
No abstract available at this time
Dabbling duck recruitment in relation to habitat and predators at Union Slough National Wildlife Refuge, Iowa
No abstract available at this time