Cynthia J. Zabel's research while affiliated with Oregon State University and other places

Publications (31)

Article
The objectives of our study were to determine the effects of commercial thinning and broadcast burning on sporocarp production of hypogeous ectomycorrhizal (HEM) fungi. At two sites in northeastern California, Jennie Springs (JS) and Swain Mountain (SM), we compared HEM sporocarp production among units that had been heavily thinned, moderately thin...
Article
Full-text available
In this paper we summarize the results of four studies in which we either examined the feeding habits of the northern flying squirrel (Glaucomys sabrinus), a mycophagous (consuming fungi) small mammal, or compared the abundance of truffles (sporocarps of hypogeous mycorrhizal fungi) among different types of fir (Abies) forest. The studies were cond...
Article
Red tree voles are one of the least understood small mammals in the Pacific Northwest, because they live in the forest canopy and are difficult to sample using conventional trapping methods. We examined the distribution and relative abundance of tree voles in different regions of Oregon based on their occurrence in diets of northern spotted owls. W...
Article
We describe local, regional, and annual variation in diets of northern Spotted Owls (Strix occidentalis caurina) in Oregon based on 24 497 prey collected at 1118 owl territories in 1970-2003. The sample included 91.5% mammals, 4.3% birds, 4.1% insects, and 0.1% other prey. The diet included a131 species, including 49 mammals, 41 birds, 3 reptiles,...
Chapter
Conservation of mammals in the coniferous forests of western North America has shifted in recent years from species-based strategies to community- and ecosystem-based strategies, resulting in an increase in the available information on mammalian communities and their management. This book provides a synthesis of the published literature on the role...
Chapter
Conservation of mammals in the coniferous forests of western North America has shifted in recent years from species-based strategies to community- and ecosystem-based strategies, resulting in an increase in the available information on mammalian communities and their management. This book provides a synthesis of the published literature on the role...
Chapter
Full-text available
Conservation of mammals in the coniferous forests of western North America has shifted in recent years from species-based strategies to community- and ecosystem-based strategies, resulting in an increase in the available information on mammalian communities and their management. This book provides a synthesis of the published literature on the role...
Article
In order to test the veracity of currently accepted ideas about Northern Spotted Owl (Strix occidentalis caurina). habitat associations in the Klamath Province of northern California (USA) we compared different habitat descriptions using predictive habitat-association models. The current description used by federal agencies and new descriptions bas...
Article
Full-text available
Bat detectors are widely used to compare bat activity among habitats. We placed 8 Anabat II detectors at 2 heights, 3 directions, and 2 angles with respect to horizontal to evaluate the effect of detector orientation on the number of bat detections received. The orientation receiving the maximum number of detections had 70% more detections than the...
Article
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Our goal was to describe and evaluate patterns of association between stream size and abundances of amphibians and small mammals in a northwestern California watershed. We sampled populations at 42 stream sites and eight upland sites within a 100-km(2) watershed in 1995 and 1996. Stream leaches sampled ranged from poorly defined channels that rarel...
Article
Bats are known to use areas above perennial streams and rivers for foraging and traveling; however, little is known about bat use of smaller streams that flow intermittently. We compared bat activity among 3 size classes of streams and upland sites in a northwestern California watershed during summers 1996 and 1997. Stream size was classified based...
Article
Bats are known to use areas above perennial streams and rivers for foraging and traveling; however, little is known about bat use of smaller streams that flow intermittently. We compared bat activity among 3 size classes of streams and upland sites in a northwestern California watershed during summers 1996 and 1997. Stream size was classified based...
Article
Understanding habitat relationships of forest-dwelling bats has become a wildlife management priority during the past decade. We used radiotelemetry to examine the use of day roosts by fringed myotis (Myotis thysanodes) in a Douglas-fir (Pseudotsuga menziesii) forest in northern California. We located 52 roosts in 23 trees and compared the characte...
Article
Northern Spotted Owl (Strix occidentalis caurina) reproduction and turnover (when an owl died or shifted territories, and was replaced by another owl) were monitored at 51 locations on Simpson Timber Company lands, northwestern California, from 1991- 1995. We tested for differences in proportions of five stand age classes and reproductive success b...
Article
We monitored reproductive success of northern spotted owls (Strix occidentalis caurina) at 51 sites on Simpson Timber Company's (STC) managed, young-growth forests in northwestern California from 1991 to 1995. We compared habitat characteristics between sites with high and low fecundity at 5 spatial scales (concentric circles of 7, 50, 114, 203, an...
Article
old-growth forests suggest that logging led to significant increases in populations o f golden- mantled ground squirrels (Spermophilus lateralis), yellow pine chipmunks (Tamias amoe- nus), and lodgepole chipmunks (Tamias speciosus) but may have led to reduced populations of western red-backed voles (Clethrionomys californicus). Capture rates of Dou...
Article
Few studies have examined fruiting patterns of hypogeous fungi, and relationships between sporocarp production of hypogeous fungi and forest habitat components such as organic soil depth and amounts of decayed wood are poorly understood. We sampled sporocarps of hypogeous fungi (truffles) in four old-growth (> 200 years) and four paired, mature (ca...
Article
Hypogeous sporocarps of mycorrhizal fungi (truffles) are a common food of northern flying squirrels (Glaucomys sabrinus) and many other species of small mammals. Forest management practices and natural disturbances can affect both total amounts and species composition of truffles. We conducted cafeteria-style feeding trials to compare preferences o...
Article
Glaucomys sabrinus is the primary prey of northern spotted owls (Strix occidentalis caurina) and California spotted owls (S.o. occidentalis) throughout much of the owls' ranges. The authors compared flying squirrel densities among three types of fir (Abies spp.) forests in Lassen National Forest, NE California. In 1990 flying squirrel density was g...
Article
Full-text available
433 Abstract: Correlations between the home-range size of northern spotted owls (Strix occidentalis caurina) and proportion of their range in old-growth forest have been reported, but there are few data on the relationship between their home-range size and prey. The primary prey of spotted owls are wood rats and northern flying squirrels (Glaucomys...
Article
Full-text available
Home range is an "area utilized by an individual during its normal activities such as food gathering, mating, and caring for young " (Burt 1943), as distinguished from its territory, which is typically defended against intrusion by other individuals of the same species, except a mate or a potential mate (Nice 1941). Home ranges of neighboring indiv...
Article
Full-text available
The radio-tracking study area on the Lassen National Forest (NF) reported in Chapter 6 was coincidentally an area for which we were able to locate nearly complete records of logging. It was also an area for which we had much information about the vegetation. Based on these records, we have visually examined patterns of habitat use by radio-tagged s...
Article
Fifteen of 47 radio-tagged northern spotted owls (Strix occidentalis caurina) died during a 2-year study in northern California, and 11 of 33 radio-tagged California spotted owls (S. o. occidentalis) died in 2.5 years in the Sierra Nevada. Female owls with 19-g radio tags had significantly lower annual survival rates than color-banded females (P =...
Article
Full-text available
We compared a set of competing logistic regression habitat selection models for Northern Spotted Owls (Strix occidentalis caurina) in California. The habitat selection models were estimated, compared, evaluated, and tested using multiple sample datasets collected on federal forestlands in northern California. We used Bayesian methods in interpretin...

Citations

... Several studies have been conducted on ACO use in amphibians and reptiles in North America, with a few ACO studies involving small mammals (Waters et al. 2001;Hampton 2007;Joppa et al. 2009;Kapfer and Munoz 2012;Halliday and Blouin-Demers 2015). ACO success is highly variable throughout North America, and the probability of finding animals associated with ACOs is probably based on temperature, habitat, and natural history of species. ...
... For small, perennial streams a distance of 10 m was used. The difference in approach for smaller streams was based on the idea that such streams are a significantly smaller foraging resource and as such would have a more limited nutrient value in the landscape (Seidman and Zabel, 2001). Relative frequency of habitat types was evaluated to ensure that there was adequate habitat diversity present for a comparative analysis. ...
... Since lichens play an important role in forest ecosystems, such as, contributing to forest biodiversity (Dettki and Esseen 1998;Kuusinen and Siitonen 1998;Lesica et al. 1991;Pharo et al. 1999), used as forage by many animals (Rosentreter et al. 1997;Zabel and Waters 1997), provide nesting material for birds (Hayward and Rosentreter 1994;Starkey and Hagar 1999), constitute preferred habitat for many invertebrates (Pettersson et al. 1995), involved in nutrient cycling (Boucher and Nash 1990;Esseen et al. 1996;Knops et al. 1991;Pike 1978), but their number is declining day by day and many of the lichen species are becoming rare, as their living area due to the activities of human being is either being destroyed or all too frequently is subjected to change. The evidence for this decline is produced by old publications about the lichen flora, from others still maintaining access to collections of lichens from an earlier time. ...
... Other recent research on red tree voles includes determining their distribution and abundance based on occurrence in pellets regurgitated by a principal predator, northern spotted owls(Forsman et al. 2004 . Working in Oregon, the authors found that the incidence of red tree voles in the owl pellets occurred most commonly in the central and southcoastal regions, were relatively sparse in the northern Coast Range and Cascades areas of the state, and were absent from pellets on the east slope of the Cascade Mountains and most of the dry forest area in south central Oregon. ...
... The early successional forest-floor species typically decline in abundance as canopy closure occurs in coniferous stands. The red squirrel and northern flying squirrel occupy older forests with tall trees, complex stand structure, snags, and large-diameter woody debris [48]. However, both sciurids seem to persist in a relatively broad range of young managed forest habitats, as well as in old-growth stands [43]. ...
... Our interest in counts as indices of abundance was motivated, in part, by a concern that historical (or current) conclusions based on counts might be dismissed out of hand (e.g., a criticism of Carey et al. 1992 by Rosenberg et al. 1994). Although counts are inadequate estimates of population size, they may provide indices of abundance. ...
... Thomas's Rope Squirrel Emmons (1980), Gautier-Hion et al. (1980), Happold (1996) Funisciurus isabella Lady Burton's Rope Squirrel Emmons (1980), Gautier-Hion et al. (1980), Happold (1996) Funisciurus lemniscatus Ribboned Rope Squirrel Emmons (1980), Gautier-Hion et al. (1980) Funisciurus pyrropus Fire-footed Rope Squirrel Emmons (1980), Gautier-Hion et al. (1980), Happold (1996) Glaucomys oregonensis Humboldt's Flying Squirrel Tevis (1953), McKeever (1960), Maser et al. (1978a), Maser et al. (1978b), Gunther et al. (1983), Maser et al. (1985), Maser et al. (1986), Maser & Maser (1988a), Hall (1991), Carey (1991), Carey (1995), Waters & Zabel (1995), Carey et al. (1996), Colgan (1997) ...
... At lower elevations, spotted owl territory occupancy and breeding probabilities tend to be higher, home ranges smaller, and woodrats more prevalent in the diet , Hobart et al. 2019a. Moreover, spotted owl breeding probabilities can be positively associated with the prevalence of younger forests at low elevations where there is a significant hardwood component (a forest type that likely harbors relatively abundant woodrat populations) in owl territories (Thome et al. 1999, Hobart et al. 2019b. But territory occupancy can be Notes: All covariates showed significant interaction with elevation in the underlying step or resource selection model (see Appendix S2 for parameter estimates and associated measures of uncertainty). ...
... At each detector location, we measured the microhabitat variables that could influence species-specific activity patterns at a local scale. We used a 0.1 ha circular plot (17.8 m radius) centered on the detector [63,68,69]. We used a clinometer (Suunto Oy: Vantaa, Finland) to assess the overstory and understory (if applicable) height (m) within the stand and measured canopy cover using a GRS densitometer (Forestry Suppliers, Inc: Jackson, MS, USA). ...
... These thinning operations provided an opportunity to establish a replicated forest management-scale before-after-control-impact (BACI) study to experimentally assess the effects of thinning on forest structure and a broad suite of fauna. Few experimental assessments have been established globally to assess the effects of thinning on fauna (but see Welsh et al. 2015), with these often limited to single fauna groups. We report on the 1-2 year post-thinning response of forest structural components (stem densityalive or dead, hollow-bearing trees, coarse woody debris (CWD) density and volumes) and multiple fauna groups (bats, birds, volant insects and non-volant mammals). ...