Differences in trapping mortality rates of northern flying squirrels

1993 ◽  
Vol 71 (3) ◽  
pp. 660-663 ◽  
Author(s):  
Daniel K. Rosenberg ◽  
Robert G. Anthony
Keyword(s):  
Mortality Rates ◽  
Differential Mortality ◽  
Glaucomys Sabrinus ◽  
Adult Males ◽  
Extrinsic Factors ◽  
Age Cohorts ◽  
Flying Squirrels ◽  
Northern Flying Squirrel ◽  
Northern Flying Squirrels ◽  
Juvenile Males

We described trapping mortality rates of northern flying squirrel (Glaucomys sabrinus) populations in western Oregon, U.S.A., and evaluated the effects of sex, age, body mass, and number of times an individual was recaptured on these rates. Although the overall trapping mortality rates were relatively low (7%) during 16–21 day trapping sessions, we observed differential mortality rates among the sex and age cohorts. The order of mortality rates was: juvenile females (32.3%) > juvenile males (11.1%) > adult females (5.1%) = adult males (4.1%). Overall trapping mortality rates were not affected by the number of times an individual was captured. We hypothesize that the differences we found were due to extrinsic factors (weather-related) acting on differential behavioral responses to trapping and thresholds of stress an animal can tolerate.

Den trees used by northern flying squirrels (Glaucomys sabrinus) in southeastern Alaska

2002 ◽  
Vol 80 (9) ◽  
pp. 1623-1633 ◽  
Author(s):  
V J Bakker ◽  
K Hastings
Keyword(s):  
Small Groups ◽  
Random Trees ◽  
High Rate ◽  
Limiting Factor ◽  
Glaucomys Sabrinus ◽  
Flying Squirrel ◽  
Flying Squirrels ◽  
Northern Flying Squirrel ◽  
Den Site Selection ◽  
Northern Flying Squirrels

Northern flying squirrel (Glaucomys sabrinus) dens are reportedly associated with features characteristic of older forests, and den availability is a potential limiting factor in younger forests. We assessed den sites used by northern flying squirrels in southeastern Alaska, where we expected den-site selection to differ from more southerly forests, owing to increased thermal stress but reduced predation and competition. We located 27 squirrels in 76 dens and compared den trees with 1875 matched random trees. Most dens ([Formula: see text]73%) were in cavities and 21% were at heights of [Formula: see text]3 m. This high rate of cavity use, including cavities low in the bole, likely reflects the importance of weatherproof dens in this cool wet region. Northern flying squirrels preferentially used trees with indicators of cavity presence, selecting for snags and for larger diameter trees with bole entries, conks, abundant mistletoe, and dead tops. Although cavity availability is probably not limiting populations in this region currently, cavity-supporting trees would be one of the last elements of old-growth forests to develop in intensively logged stands. Retention of small groups of large snags and live trees exhibiting evidence of disease or physical defects would ensure availability of denning structures after logging.

scholarly journals Fungi in the diets of northern flying squirrels and lodgepole chipmunks in the Sierra Nevada

2005 ◽  
Vol 83 (12) ◽  
pp. 1581-1589 ◽  
Author(s):  
Marc D Meyer ◽  
Malcolm P North ◽  
Douglas A Kelt
Keyword(s):  
Sierra Nevada ◽  
Glaucomys Sabrinus ◽  
Dietary Overlap ◽  
Conifer Forest ◽  
Seasonal Differences ◽  
Flying Squirrels ◽  
Northern Flying Squirrel ◽  
Mixed Conifer Forest ◽  
Northern Flying Squirrels ◽  
Teakettle Experimental Forest

The diets of a fungal specialist, northern flying squirrel (Glaucomys sabrinus (Shaw, 1801)), and a dietary generalist, lodgepole chipmunk (Neotamias speciosus (Merriam, 1890)), were examined in the old-growth, mixed-conifer forest at the Teakettle Experimental Forest in California's southern Sierra Nevada. Spores of fungi were identified from fecal pellets collected from both species during spring and summer of 1999 through 2002. Frequency of fungi in the diets of both squirrel species was consistently high across all seasons and years of study. Overall, G. sabrinus diets contained about 30% greater richness and evenness of fungal taxa than N. speciosus diets. There were no seasonal differences in richness and evenness of fungal taxa in squirrel diets. Richness of fungal taxa in diets was positively correlated with hypogeous sporocarp biomass and rainfall from June through August for N. speciosus but not for G. sabrinus. Dietary overlap between G. sabrinus and N. speciosus was high with respect to the most frequently consumed fungal taxa, although Gautieria and Gastroboletus were consumed in greater proportions by G. sabrinus than N. speciosus. Our results indicate that in the southern Sierra Nevada both G. sabrinus and N. speciosus were frequent consumers of a similar, diverse assemblage of fungal taxa and that consumption was proportional to seasonal differences in availability. For the more strongly mycophagist G. sabrinus, however, diet had a greater proportion of select fungal taxa and avoidance of less desirable taxa.

Food habits of the northern flying squirrel (Glaucomys sabrinus) in Oregon

1985 ◽  
Vol 63 (5) ◽  
pp. 1084-1088 ◽  
Author(s):  
Zane Maser ◽  
Chris Maser ◽  
James M. Trappe
Keyword(s):  
Food Habits ◽  
Food Source ◽  
Coniferous Forests ◽  
Glaucomys Sabrinus ◽  
Hypogeous Fungi ◽  
Flying Squirrel ◽  
Flying Squirrels ◽  
Food Items ◽  
Northern Flying Squirrel ◽  
Northern Flying Squirrels

Digestive tracts of 91 northern flying squirrels (Glaucomys sabrinus) were analyzed for food items; 28 were from northwestern Oregon and 63 from northeastern Oregon. Ninety percent or more of the ingested materials were fungi and lichens, including 20 genera of hypogeous fungi. The northern flying squirrel, in using hypogeous fungi as a major food source, is an important nocturnal disperser of the spores. In Oregon coniferous forests, these fungi are obligatory ectomycorrhizal symbionts with the trees in which the squirrels live.

Modeling impacts of landscape connectivity on dispersal movements of northern flying squirrels (Glaucomys sabrinus griseifrons)

2019 ◽  
Vol 394 ◽  
pp. 44-52 ◽  
Author(s):  
Stephanie E. Trapp ◽  
Casey C. Day ◽  
Elizabeth A. Flaherty ◽  
Patrick A. Zollner ◽  
Winston P. Smith
Keyword(s):  
Landscape Connectivity ◽  
Glaucomys Sabrinus ◽  
Flying Squirrels ◽  
Northern Flying Squirrels

Winter nest trees of sympatric northern and southern flying squirrels: a test of reinforcement in a hybrid zone

2021 ◽  
Author(s):  
Paul Philip O'Brien ◽  
Jeff Bowman ◽  
Andrea Coombs ◽  
Sasha Newar ◽  
Colin J. Garroway
Keyword(s):  
Secondary Contact ◽  
Glaucomys Sabrinus ◽  
Closely Related Species ◽  
Flying Squirrels ◽  
Hardwood Trees ◽  
Weak Evidence ◽  
Northern Flying Squirrels ◽  
Habitat Suitability Modelling ◽  
Classification Information ◽  
Nest Type

Shifting range boundaries can lead to secondary contact of closely related species, which might in turn lead to hybridization when the evolution of reproductive isolation is incomplete. We examined winter nest use of northern (Glaucomys sabrinus Shaw, 1801) and southern flying squirrels (G. volans Linnaeus, 1758) in an area of recent secondary contact and known hybridization in Ontario, Canada to test for evidence of reinforcement due to different and diverging nesting behaviours. We radio-collared 26 flying squirrels (12 G. sabrinus and 14 G. volans) between two survey periods (winters of 2008-9 and 2019-20) and identified all nest trees used by individuals throughout each winter. For each nest tree we identified the nest type and collected tree classification information to compare differences in nest use between species. We also present a novel application of habitat suitability modelling to test for evidence of divergence in nest use through time, which would suggest reinforcement. We found southern flying squirrels used a higher proportion of cavities in large, hardwood trees, whereas northern flying squirrels used more external nests and softwood trees. Conditional probabilities provided some evidence for increased differentiation in nest use by flying squirrels through time. Overall, we found relatively little overlap in winter nest use between flying squirrel species, despite evidence for hybridization at this site, and some weak evidence for increased divergence between species in nest use over 11 years

scholarly journals Spatial Organization of Northern Flying Squirrels,Glaucomys sabrinus: Territoriality in Females?

2011 ◽  
Vol 71 (1) ◽  
pp. 44-48 ◽  
Author(s):  
Jaya R. Smith ◽  
Dirk H. Van Vuren ◽  
Douglas A. Kelt ◽  
Michael L. Johnson
Keyword(s):  
Spatial Organization ◽  
Glaucomys Sabrinus ◽  
Flying Squirrels ◽  
Northern Flying Squirrels
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