Home Range and Population Density of Fishers in Eastern Ontario

Abstract: Fishers (Martes pennanti) were almost extirpated in Ontario, Canada, south of the French and Mattawa rivers by the 1940s but have recolonized much of their former range over the past several decades. We assessed the effect of the current harvest quota on a fisher population in eastern Ontario by estimating home range size and population density from a sample of radiocollared animals. Mean (± SD) adult home ranges (based on annual 95% min. convex polygons) were consistently smaller than those reported in the literature (M: 11 ± 4.4 km²; F: 2.1 ± 0.8 km²), with up to 71% overlap of adjacent intrasexual home ranges. This yielded an estimated adult fisher population density of 32.7/100 km² of suitable habitat, as defined by the habitat composition within observed home ranges. We further estimated that between 2003 and 2005, trappers harvested 17.8-42.3% of the pretrapping population. These results suggest that although current fisher population density is high in our study area compared to reported densities in other areas, harvest rate is also high and an increase in quota is unwarranted.     

Diverticulum of the urinary bladder in a woman

In the two cases of congenital absence of the vagina reported herein, the embryologic point of arrest of development of the mullerian ducts was identical. Both patients had a rudimentary uterus, and one had a fibroid tumor on the rudimentary uterus. As a part of operation to construct a vagina in such cases, exploratory pelvic laparotomy appears to be a desirable step in order to determine the status of the internal genital organs. The use of a split thickness skin graft sewn around a vaginal mold and inserted into the dissected vaginal space results in more rapid healing, less scar tissue and a vagina that is soft, pliable and normal in appearance, even to the extent of having rugal folds.     

Orientation behaviour in the Grayling butterfly: thermoregulation or crypsis?

ABSTRACT.

• 1 Body orientation and wing tilting in Hipparchia semele (L.) have been explained previously both by the need for shadow-minimization (crypsis hypothesis) and by the need to regulate body temperature (thermoregulation hypothesis).
• 2 This study tests the thermoregulation hypothesis by quantifying butterfly orientation in relation to sun position, using vector analysis, and correlating the data with ambient temperature and time of day.
• 3 During sunshine, Graylings tend to present a maximal wing area to the sun's rays when the ambient temperature is relatively low, and a minimal area when it is high ('sunning’and‘heat-avoiding’positions respectively).
• 4 On cool sunny days, butterflies adopt sunning positions throughout the day, whereas on warm sunny days they adopt sunning positions during the outlying periods and heat-avoiding positions in the middle period of the day. Correlations between wing exposure and both ambient temperature and time of day are statistically significant for warm sunny days.
• 5 During overcast weather, butterfly orientation is very variable and possibly random.
• 6 Analysis of sunny day data supports the thermoregulation hypothesis. This is discussed in relation to other known types of thermoregulatory behaviour observed in this species: stilting, shade-seeking, ground-hugging and shivering.
• 7 Conversely, the results do not support the crypsis hypothesis.

     

Water Transport in Isolated Maize Roots

A simple model has been devised which predicts the concentration,C^x_s, of salt (e.g. KCl) in the exudate from isolated roots asa function of the salt concentration, C⁰_s, in the medium. Thechief assumption, made in deriving the relationship betweenC^x_s and C⁰₅, is that the exudation of water, J, from the rootsconsists of two components (one being osmotic, Ø, inorigin and the other, Ø⁰, flowing in the absence of anosmotic gradient). The exudation of salt, J_s, calculated asJ C^x_s, was found to be dependent on C⁰_s. Our investigationson maize roots were concerned with estimations of L_p and Ø^vand determinations of C^x_s as a function of C⁰_s. Satisfactoryagreement between prediction and experiment was found in thesepreliminary studies. It is considered that water movement inisolated roots can be explained by a simple osmotic model withthe additional possibility that a relatively small non-osmoticwater flow occurs.     

THE EFFECT OF MASTICATORY PATTERNS AS MEASURED BY TIME-INTENSITY AND ELECTROMYOGRAPHY ON THE PERCEPTION OF BOVINE MUSCLE TENDERNESS

The relationship between perception of tenderness and chewing activity was explored using the Time-Intensity measurement of perception and electromyographic measurements of masseter muscle movement. Semitendinosus muscles from eight treatments of forage fed beef were evaluated by nine individuals. The Time-Intensity parameters of Area Under the Curve and Decrease Area were the most useful for treatment separation based on tenderness. Information was obtained from the electromyogram regarding the number of chews, time to chew and mastication rate. However, more work with EMG measurements is required to accurately study the effect of masticatory patterns on tenderness perception.