scholarly journals Testing the parasite-mediated competition hypothesis between sympatric northern and southern flying squirrels

2021 ◽  
Author(s):  
Paul P. O'Brien ◽  
Jeff Bowman ◽  
Sasha L. Newar ◽  
Colin J. Garroway
Keyword(s):  
Flying Squirrels ◽  
Competition Hypothesis

scholarly journals Wolf, Canis lupus, Pup Mortality: Interspecific Predation or Non-Parental Infanticide?

2011 ◽  
Vol 125 (2) ◽  
pp. 158 ◽  
Author(s):  
A. David M. Latham ◽  
Stan Boutin
Keyword(s):  
Canis Lupus ◽  
Resource Competition ◽  
The Other ◽  
Gray Wolf ◽  
Gps Collar ◽  
Competition Hypothesis ◽  
Interspecific Predation ◽  
Pup Mortality ◽  
First Time

A breeding male Gray Wolf, Canis lupus, equipped with a GPS collar was documented going to the den site of another Gray Wolf pack. This trip was coincident with an attack on the den of the other pack and the occurrence of a dead and partially consumed Gray Wolf pup at the same location. We present two possible explanations - interspecific predation and non-parental infanticide - to account for this observation. Because the Gray Wolf with the GPS collar and his mate were first-time breeders and were attempting to establish a territory space of their own, we speculate that, based on the available evidence, this observation most likely represents a case of non-parental infanticide that fits the predictions of the resource competition hypothesis.

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

Photoperiod synchronizes reproduction and growth in the southern flying squirrel,Glaucomys volans

1990 ◽  
Vol 68 (1) ◽  
pp. 134-139 ◽  
Author(s):  
Theresa M. Lee ◽  
Irving Zucker
Keyword(s):  
Body Weight ◽  
Reproductive Condition ◽  
Glaucomys Volans ◽  
Flying Squirrel ◽  
Seasonal Rhythms ◽  
Flying Squirrels ◽  
Body Weights ◽  
Natural Photoperiod ◽  
Ad Libitum ◽  
Southern Flying Squirrel

Southern flying squirrels were housed in a simulated natural photoperiod for 40°N latitude and held at a constant temperature of 23 °C with food and water provided ad libitum. Body weight and reproductive condition were monitored weekly for 2 years. Males were in reproductive condition between January and mid-August and females were in estrus from late February to mid-April and again from mid-June until early August. Young were conceived during both estrous periods and several squirrels produced two litters in the same year. Minimum body weights were recorded in adults in mid-October each year. Pups born in the spring grew more rapidly than those from summer litters, and reached puberty at 2.5 months as compared with 6–8 months of age for the summer litters. Several seasonal rhythms appear to be controlled by photoperiod in this species.

Distribution and relative abundance of giant squirrels and flying squirrels in Karnataka, India / Distribution et abondance relative des espèces d'écureuils géants et volants à Karnataka, Inde

Mammalia ◽  
2006 ◽  
Vol 70 (1-2) ◽  
Author(s):  
Honnavalli N. Kumara ◽  
Mewa Singh
Keyword(s):  
Relative Abundance ◽  
Eastern Ghats ◽  
Northern Population ◽  
Flying Squirrel ◽  
Evergreen Forests ◽  
Flying Squirrels ◽  
Major Threat ◽  
Distributional Range ◽  
Abondance Relative ◽  
The Western Ghats

AbstractWe assessed the distribution and relative abundance of giant squirrels and flying squirrels in the state of Karnataka, India. Two species of giant squirrels, the Indian giant squirrel and the grizzled giant squirrel, and two species of flying squirrel, the large brown flying squirrel and the small Travancore flying squirrel, were found to occur in Karnataka. Indian giant squirrels and large brown flying squirrels were more widely distributed than the other two species. The distributional range included the forests of the Western and Eastern Ghats. However, their distribution was confined only to forests with tall trees. Indian giant squirrels and large brown flying squirrels occur in both deciduous and evergreen forests. Small Travancore flying squirrels occupied high-rainfall evergreen forests on western slopes in the Western Ghats, and the grizzled giant squirrels occupy riverine forests. This report of the small Travancore flying squirrel is the first of this species from Karnataka, and this population is the most northern population of its distributional range. Hunting was found to be a major threat, and influenced the abundance of all species except the grizzled giant squirrel. Hunting was primarily for domestic consumption.

scholarly journals Responses of New World flying squirrels to the acute stress of capture and handling

2015 ◽  
Vol 97 (1) ◽  
pp. 80-88 ◽  
Author(s):  
Lanna M. Desantis ◽  
Jeff Bowman ◽  
Candace V. Lahoda ◽  
Rudy Boonstra ◽  
Gary Burness
Keyword(s):  
Stress Response ◽  
New World ◽  
Binding Capacity ◽  
Biologically Active ◽  
Stress Axis ◽  
Neutrophil Lymphocyte Ratio ◽  
Flying Squirrels ◽  
Physiological Variables ◽  
Total Cortisol ◽  
Cortisol Levels

Abstract Northern ( Glaucomys sabrinus ) and southern ( G. volans ) flying squirrels have glucocorticoid (GC; stress hormone) levels higher than most vertebrates but virtually no binding capacity for these GCs via the carrier protein, corticosteroid-binding globulin. Thus, their total GCs are essentially all free and biologically active. However, the GC estimates come from blood samples taken after squirrels had been in live traps, and thus in a stress-induced state. Obtaining baseline values for physiological variables is valuable for assessing the response of vertebrates to stressors in their environment. We compared baseline plasma total cortisol levels (within 3min of capture) to stress-induced levels (after 30min of trap restraint) in both flying squirrel species. We recorded baseline cortisol levels that were some of the highest ever reported for mammals, indicating their stress axes operate at a higher set point than most other species. As part of the stress response, we also measured 4 indices in addition to cortisol. Total cortisol and free fatty acids increased in both species, as predicted. In contrast with our predictions, blood glucose and neutrophil/lymphocyte ratio showed no overall change, and hematocrit decreased significantly. New World flying squirrels therefore appear to have a stress response that differs from many other mammals. The selective forces driving the physiology of these animals remain elusive, but this lineage may provide an interesting comparative system for the study of stress axis function and its evolution among vertebrates.

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.

Sign in / Sign up

Export Citation Format

Share Document