scholarly journals Consumption of Truffles and other Fungi by the American Red Squirrel (Tamiasciurus hudsonicus) and the Eastern Chipmunk (Tamias striatus) (Sciuridae) in Northwestern Ontario

2013 ◽  
Vol 127 (1) ◽  
pp. 57 ◽  
Author(s):  
Jocelin N. Teron ◽  
Leonard J. Hutchison

Faecal matter collected from the American Red Squirrel (Tamiasciurus hudsonicus) and the Eastern Chipmunk (Tamias striatus) on the campus of Lakehead University in Thunder Bay, Ontario, was examined for the presence of consumed fungal tissue. A total of 14 faecal samples were collected from live-trapped animals over six trapping periods (19 June to 25 September 2010). Eight samples contained intact remains of spores representative of hypogeous truffle fungi found in the genera Elaphomyces, Gautieria, Hymenogaster, Hysterangium, and Leucangium, as well as spores of epigeous mushrooms found in the orders Boletales and Pezizales and possibly in the family Tricholomataceae of the Agaricales. The results of this brief survey suggest not only the importance of mycophagy in the diet of American Red Squirrels and Eastern Chipmunks in the boreal mixed wood forests of northwestern Ontario but also the important role played by sciurids in vectoring spores of truffle fungi in this region.

1988 ◽  
Vol 120 (12) ◽  
pp. 1113-1121 ◽  
Author(s):  
Y.H. Prévost ◽  
J.E. Laing ◽  
V.F. Haavisto

AbstractThe seasonal damage to female reproductive structures (buds, flowers, and cones) of black spruce, Picea mariana (Mill.) B.S.P., was assessed during 1983 and 1984. Nineteen insects (five Orders) and the red squirrel, Tamiasciurus hudsonicus (Erxleben), were found feeding on these reproductive structures. Collectively, these organisms damaged 88.9 and 53.5% of the cones in 1983 and 1984, respectively. In the 2 years, Lepidoptera damaged 61.8% of the cones in 1983 and 44.4% of the cones in 1984. The spruce budworm, Choristoneura fumiferana (Clem.), and the spruce coneworm, Dioryctria reniculelloides Mut. and Mun., were the most important pests. Cones damaged by Lepidoptera could be classed into three categories: (a) severe, yielding no seeds; (b) moderate, yielding 22.3 seeds per cone; and (c) light, yielding 37.5 seeds per cone. Undamaged cones yielded on average 39.9 seeds per cone. Red squirrels removed 18.8% of the cones in 1983 and none in 1984. The spruce cone axis midge, Dasineura rachiphaga Tripp, and the spruce cone maggot, Lasiomma anthracinum (Czerny), caused minor damage in both years. Feeding by spruce cone axis midge did not reduce cone growth significantly or the number of viable seeds per cone, but feeding by the spruce cone maggot did. During both years new damage by insects to the female reproductive structures of the experimental trees was not observed after mid-July. In 1983 damage by red squirrels occurred from early to late September. In 1984 damage to cones on trees treated with dimethoate was 15.6% compared with 53.5% for untreated trees, without an increase in the number of aborted cones.


2021 ◽  
Vol 102 (3) ◽  
Author(s):  
Akbar Dastjerdi ◽  
David J. Everest ◽  
Hannah Davies ◽  
Daniela Denk ◽  
Roland Zell

Dicistroviruses are single-stranded RNA viruses in the family Dicistroviridae. The viruses have mainly been detected in arthropods and are the cause of several devastating diseases in many of these species such as honeybees. Increasingly, dicistroviruses have also been detected in both mammalian and avian species in faeces, blood and liver, but with unconfirmed pathology. Here, we report a novel dicistrovirus detected in the intestinal content of a captive red squirrel with enteritis along with the disease history, pathology and genomic characterisation of the virus. Virus particle morphology resembled those of picornaviruses with a diameter of 28–32 nm but failed to be detected using a mammalian/avian pan viral microarray. Next-generation sequencing confirmed a dicistrovirus having a typical dicistrovirus genome organization, but with the polyprotein 1 being shorter by about 100 amino acids, compared to that of other dicistroviruses. Phylogenetic analysis of ORF1 and ORF2 sequences clustered the virus with two yet unassigned dicistroviruses detected in Gorilla gorilla and a freshwater arthropod and likely to be designated to a new genus. Our data further highlights the ever-growing diversity of dicistroviruses, but the clinical significance of the virus in mammalian species and particularly red squirrels has yet to be established.


2012 ◽  
Vol 90 (9) ◽  
pp. 1191-1200 ◽  
Author(s):  
A.M. Kiesow ◽  
E.M. Monroe ◽  
H.B. Britten

We selected two isolated mammalian populations, the Black Hills northern flying squirrel ( Glaucomys sabrinus (Shaw, 1801)) and red squirrel ( Tamiasciurus hudsonicus (Erxleben, 1777)), to elucidate their genetic structure. We trapped both squirrels from 2005 to 2007, in three regions of the Black Hills, differing in geology and vegetation, to collect ear samples for genetic analyses. Microsatellite loci (northern flying (9) and red squirrel (13)) were used to examine genetic structure. Data analyses estimated genetic variability, substructure, and gene flow. Northern flying and red squirrel populations have allelic diversity and observed heterozygosity similar to other isolated populations. Each species shows weak substructure from STRUCTURE and GENELAND analyses, suggesting squirrel movements may be inhibited by topography or unsuitable habitat. Recent gene flow estimates from BAYESASS indicate that both species experience some within population gene flow and red squirrels may be more structured than northern flying squirrels because of lower migration rates. Concordant patterns of genetic structure in northern flying and red squirrels indicate that other species’ movements in the Black Hills may be affected by topography and habitat. Because their habitat is isolated in the Black Hills, management practices and conservation measures are recommended to promote viability and survival of each species.


1979 ◽  
Vol 57 (7) ◽  
pp. 1349-1354 ◽  
Author(s):  
Ronald W. Pauls

Abdominal temperatures (Tb) of two captive female red squirrels (Tamiasciurus hudsonicus) in a natural outdoor environment were monitored by radiotelemetry at air temperatures (Ta) from −33 to 28 °C. Abdominal temperature ranged from 35.9 to 41.4 °C with values usually less than 39 °C when an animal was in the nest and greater than 39 °C when outside. An increase of Tb to about 39 °C usually occurred before an animal left the nest. In the nest Tb was positively correlated with Ta. Outside the nest there was a weak positive correlation at Ta less than 15 °C and a stronger negative correlation at higher Ta. During subnivean activity a rapid decline in Tb usually occurred. It is suggested that in the nest a low Tb is adaptive in that it results in energy conservation while a higher Tb is required outside the nest for rapid and coordinated motor activity.


1978 ◽  
Vol 56 (7) ◽  
pp. 1519-1525 ◽  
Author(s):  
Ronald W. Pauls

Amount and intensity of locomotor activity and time out of the nest were measured for a 1-year period on captive red squirrels (Tamiasciurus hudsonicus) under natural conditions. Daily and annual activity patterns and correlations between activity and meteorological variables were examined. A pronounced annual cycle, in phase with the annual temperature cycle, was found in all three aspects of activity. Daily amount of locomotor activity and time out of the nest were closely correlated with mean daily air temperature. Wind, photoperiod, and air temperature during the preceding week showed a weak but significant correlation with activity. Daily patterns of activity varied seasonally from a distinctly bimodal to a unimodal pattern, with a shift in winter to more midday activity. The relevance of these behavioural strategies to the energy economy of the red squirrel is discussed.


1986 ◽  
Vol 62 (4) ◽  
pp. 233-235 ◽  
Author(s):  
Louis LaPierre

Between August 15th and September 15th 1979, 1980 and 1981, 77 and 74 red squirrels, Tamiasciurus hudsonicus, were captured within the sprayed and unsprayed coniferous forest of southeastern New Brunswick. Following live capture, the squirrels were sacrificed, weighed and the reproductive tracts were removed and preserved in a 10% formalin solution.Counts of placental scars and corpora lutea of squirrels that inhabited the sprayed forest had a mean placental scar count of 3.8 and a mean corpora lutea count of 4.2. Squirrels from the unsprayed coniferous forest had a mean placental count of 3.6 and a corpora lutea count of 3.9. Statistical analyses, using the student's T-test with a probability level of 0.05, revealed no significant differences in reproductive success of the two groups of squirrels.


1971 ◽  
Vol 49 (3) ◽  
pp. 303-305 ◽  
Author(s):  
J. Homer Ferguson ◽  
G. Edgar Folk Jr.

Free fatty acid (FFA) levels were determined in warm- and cold-acclimated white rats, mice, and red squirrels (Tamiasciurus hudsonicus). FFA concentrations of the genetically cold-adapted species (red squirrel) were highest and reflect its ability to maintain high metabolic rates reported by others. In the red squirrels, FFA concentrations were elevated after cold acclimation. Acclimation of white rats and mice had no effect on FFA levels. Short-term cold exposure (−35 °C) caused the FFA levels to rise in all three species. Cold-exposed mice were found to be highest in plasma FFA content. The ability of the red squirrels to mobilize FFA during short-term exposure was enhanced by cold acclimation. The response of rats and mice to cold exposure was not changed by acclimation. This would indicate a greater capacity of the red squirrel to respond to acclimating conditions.


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