scholarly journals ARTIFICIAL INSEMINATION OF SNOWSHOE HARES (LEPUS AMERICANUS) AND THE TRANSFER OF THEIR FERTILIZED EGGS TO THE RABBIT (ORYCTOLAGUS CUNICULUS)

Reproduction ◽  
1965 ◽  
Vol 10 (3) ◽  
pp. 447-449 ◽  
Author(s):  
M. C. CHANG
1984 ◽  
Vol 62 (3) ◽  
pp. 473-479 ◽  
Author(s):  
Robert A. Kralka ◽  
W. M. Samuel

The life cycle of the lungworm Protostrongylus boughtoni Goble and Dougherty, 1943 was completed in intermediate and definitive hosts. Larvae developed to the infective third-stage in the foot of the snail Vallonia pulchella (Miiller, 1774) in 28–30 days at 18 °C. First-, second-, third-, and fourth-stage larvae are described. Patent infections developed in laboratory-reared snowshoe hares, Lepus americanus americanus, each given 50 third-stage P. boughtoni larvae per os 25 to 27 days postexposure. Periods of patency ranged from 41 to 104 days. Patent infections developed in domestic rabbits, Oryctolagus cuniculus, Dutch Belted strain, given 50 or 150 larvae in 25 to 26 days postexposure, but periods of patency ranged from 7 to 13 days and larval output was very low.


1993 ◽  
Vol 71 (7) ◽  
pp. 1385-1392 ◽  
Author(s):  
Lloyd B. Keith ◽  
Sara E. M. Bloomer ◽  
Tomas Willebrand

During November 1988 – December 1991 we livetrapped, radio-collared, and monitored the survival, reproduction, and movements of snowshoe hares (Lepus americanus) in highly fragmented habitat near the species' geographic limit in central Wisconsin. Our 7 study areas centered on 5- to 28-ha patches of prime habitat: dense stands of willow (Salix), alder (Alnus), and regenerating aspen (Populus) on poorly drained soils. Maximum hare densities averaged 1.6 – 0.8/ha, and were unrelated to patch size. Rapid declines to extinction occurred on 3 of the 5 smallest study areas; on another, where extinction seemed imminent, juvenile ingress restored the population. On the 2 largest areas (23 – 28 ha of prime habitat) hare populations were stationary during the first 2 years, but declined by 50 – 70% in the third as mean annual (September – August) survival of radio-collared hares fell from 0.27 (1988 – 1990) to 0.07 (1990 – 1991). Annual survival on the 3 extinction sites averaged just 0.015 compared with 0.179 elsewhere. Reproduction did not differ between small (5 – 7 ha) vs. larger (23 – 28 ha) patches nor between years. Estimated dispersal of adult and juvenile hares from the 5 small study areas was twice as high as from the 2 larger, viz. 16 vs. 35% annually. Dispersers appeared to have markedly lower survival. Predation, chiefly by coyotes (Canis latrans), was the proximate cause of 96% (117 of 122) of natural deaths among radio-collared hares, and was therefore the overwhelming determinant of survival and thus population trend. Results of this study suggest that probabilities of extinction in such fragmented habitat depend importantly on patch size and attendant hare numbers; i.e., fall populations of < 10 hares frequenting patches of prime habitat ≤ 5 ha are not likely to persist long without ingress.


2006 ◽  
Vol 36 (9) ◽  
pp. 2080-2089 ◽  
Author(s):  
Thomas P Sullivan ◽  
Druscilla S Sullivan ◽  
Pontus MF Lindgren ◽  
Douglas B Ransome

This study was designed to test the hypothesis that large-scale precommercial thinning (PCT) and repeated fertilization of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) would enhance relative habitat use by snowshoe hares (Lepus americanus Erxleben) in managed stands. Study areas were located near Summerland, Kelowna, and Williams Lake in south-central British Columbia, Canada. Each study area had nine treatments: four pairs of stands thinned to densities of 250, 500, 1000, and 2000 stems/ha, with one stand of each pair fertilized five times at 2-year intervals, and an unthinned stand. Understory vegetation and relative habitat use by snowshoe hares were measured annually from 1999 to 2003, 6–10 years after the onset of treatments. Mean crown volume index of herbs was significantly higher in fertilized than unfertilized stands, but density had no effect. Shrub volume was not affected by either treatment. Mean crown volume index of trees was significantly greater in the fertilized and high-density stands. Mean total richness of vascular plants was significantly reduced by fertilization. Mean total structural diversity of vegetation was highest in the low-density stands but was not affected by fertilization. Relative habitat use by hares, based on fecal pellet counts, was highest in the 2000 stems/ha and unthinned stands in summer. This pattern also occurred in winter when hare use was higher in fertilized than unfertilized stands. Overall, fertilized 2000 stems/ha stands provided habitat for hares to a degree comparable with unthinned stands of lodgepole pine.


2009 ◽  
Vol 90 (3) ◽  
pp. 761-767 ◽  
Author(s):  
Michael J. Sheriff ◽  
Louise Kuchel ◽  
Stan Boutin ◽  
Murray M. Humphries

1998 ◽  
Vol 76 (10) ◽  
pp. 1949-1956 ◽  
Author(s):  
Elizabeth A Gillis

Snowshoe hares (Lepus americanus) are multilittered synchronous breeders that produce up to four distinct litters of young each summer. I used radiotelemetry to determine the effects of juvenile cohort (i.e., litter group) and food availability on postweaning survival of hares in the southwestern Yukon during the increase phase of a hare cycle. During the study, I monitored 86 juvenile hares from control areas and areas in which supplemental food was provided. Twenty-eight-day survival did not differ between food addition and control areas for any juvenile cohort, and survival rates of juveniles (all cohorts combined) did not differ significantly from those of adults (juveniles: 0.91 per 28 days; adults: 0.93 per 28 days). However, when examined by juvenile cohort, survival of third and fourth litters was significantly lower than that of adults and first and second litters. These differences were the result of differential survival among the juvenile cohorts during a 3-month period in the fall (September-November). Predation was the primary proximate cause of death for weaned juvenile hares, accounting for 86% of deaths.


1981 ◽  
Vol 17 (2) ◽  
pp. 303-310 ◽  
Author(s):  
RANDALL L. ZARNKE ◽  
THOMAS M. YUILL

1992 ◽  
Vol 70 (9) ◽  
pp. 1787-1791 ◽  
Author(s):  
Mark O'Donoghue ◽  
Carita M. Bergman

Juvenile snowshoe hares (Lepus americanus) were radio-tagged at birth to examine predispersal movements, maternal–juvenile interactions, and timing of natal dispersal. Hare litters stayed at their natal sites for an average of 2.7 days, after which each individual usually found a separate hiding place from its littermates. Observations at natal sites suggested that adult female hares nursed their litters only once per day, shortly after twilight. Some females aggressively defended their newborn litters before the juveniles left the natal site. Juvenile hares ranged progressively further from their natal sites as they grew, up to the age of 20 days. From 20 to 35 days of age, leverets stayed approximately 75 m from their natal sites, after which time their movements again increased. Natal dispersal of juvenile hares began shortly after weaning at 24–28 days of age. Many third-litter juveniles were nursed for a longer period lasting at least 29–40 days. Juvenile males may disperse sooner and travel further than females from their natal ranges.


Sign in / Sign up

Export Citation Format

Share Document