Predation of a Beaver (Castor canadensis) by a Gray Wolf (Canis lupus) during Winter

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.

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Oocyte and ovary morphological observation of gray wolf (Canis lupus)

Animal Biology ◽

10.1163/157075610x516475 ◽

2010 ◽

Vol 60 (3) ◽

pp. 249-257

Author(s):

Xu-Guang Liu ◽

Zhi-Zhong Zhang ◽

Yun-Hai Zhang ◽

Yun-Sheng Li ◽

Fu-Gui Fang ◽

...

Keyword(s):

Histological Examination ◽

Reproductive System ◽

Canis Lupus ◽

Smooth Surface ◽

Uterine Horn ◽

Left Ovary ◽

Morphological Observation ◽

Gray Wolf ◽

Antral Follicles ◽

The Right

AbstractThe present study was carried out to describe the reproductive system of a single adult female wolf, including the uterine horns, cervix, ovaries and follicles. The cumulus oocytes complexes (COCs) and oocytes were also examined. The results showed that the size of each ovary was about 9 × 6 mm with an average of weight of 461.3 mg. The uterus was Y-shaped, and the length of each uterine horn was 14 cm. The distance from the cervix to the bifurcation of the uterine horns was also 14 cm. The left ovary had two large follicles on the surface with a diameter more than 4 mm, while the right ovary had no protuberant follicles. The ovaries were covered with a lot of fat, and were well developed. The COCs derived from the antral follicles were dark, and the nuded oocytes had a dark cytoplasm. The diameter of the oocytes removed from the antral follicles was 116.8 μm on average. The ovaries had a smooth surface and all the follicles were under the surface except for two big follicles on the left ovary. Histological examination of the ovaries by haematoxylin and eosin staining demonstrated that the primordial, primary, preantral and antral follicles were scattered in the cortex, the medulla was abundant with blood vessels. This study preliminarily reveals the features of the wolf reproductive system and the structure of its oocytes and ovaries, which might be indicative for further study and the protection of the species.

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Caught Napping by (Sea) Wolves: International Wildlife Law and Unforeseen Circumstances Involving the Killer Whale (Orcinus orca) and the Gray Wolf (Canis lupus)

What's Wrong with International Law? ◽

10.1163/9789004294585_016 ◽

2015 ◽

pp. 199-213 ◽

Cited By ~ 1

Keyword(s):

Canis Lupus ◽

Killer Whale ◽

Orcinus Orca ◽

Gray Wolf

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Enhanced Asymptomatic Systemic Infection Caused by Plesiomonas shigelloides in a Captive Gray Wolf (Canis lupus)

Veterinary Sciences ◽

10.3390/vetsci8110280 ◽

2021 ◽

Vol 8 (11) ◽

pp. 280

Author(s):

Kyootae Kim ◽

Haeseung Lee ◽

Dongmi Kwak

Keyword(s):

Canis Lupus ◽

Rare Case ◽

Systemic Infection ◽

Liver Parenchyma ◽

Nucleotide Sequencing ◽

Gray Wolf ◽

Air Bubbles ◽

Plesiomonas Shigelloides ◽

Systemic Infections ◽

Cultured Bacteria

A 7-year-old male gray wolf was found dead at a zoo during exhibition. To determine the cause of death, histological and gross necropsy diagnoses and a molecular analysis were performed. The gross necropsy revealed a swollen abdomen, hemorrhagic exudates around the mouth, splenomegaly, a discolored liver, a congested kidney, hemorrhagic ascites, and dark gray-colored membranes and air bubbles in the fundus of the stomach. Rod-shaped bacteria were found in the liver parenchyma and hemorrhagic ascites using Giemsa staining. The nucleotide sequencing of the cultured bacteria identified the causative agent as Plesiomonas shigelloides, which is rarely responsible for systemic infections. This study describes a rare case and the first reported systemic gastrointestinal infection due to P. shigelloides in a zoo animal.

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Isolation and RFLP genotyping of Toxoplasma gondii from the gray wolf (Canis lupus)

Veterinary Parasitology ◽

10.1016/j.vetpar.2013.05.011 ◽

2013 ◽

Vol 197 (3-4) ◽

pp. 685-690 ◽

Cited By ~ 13

Author(s):

J.P. Dubey ◽

S. Choudhary ◽

L.R. Ferreira ◽

O.C.H. Kwok ◽

E. Butler ◽

...

Keyword(s):

Toxoplasma Gondii ◽

Canis Lupus ◽

Gray Wolf

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Impacts of recolonizing gray wolves (Canis lupus) on survival and mortality in two sympatric ungulates

Canadian Journal of Zoology ◽

10.1139/cjz-2017-0282 ◽

2018 ◽

Vol 96 (7) ◽

pp. 760-768 ◽

Cited By ~ 2

Author(s):

J.A. Dellinger ◽

C.R. Shores ◽

M. Marsh ◽

M.R. Heithaus ◽

W.J. Ripple ◽

...

Keyword(s):

Canis Lupus ◽

Mule Deer ◽

Survival Rates ◽

Odocoileus Hemionus ◽

Mortality Rates ◽

Adult Survival ◽

Mortality Data ◽

Gray Wolf ◽

Gray Wolves ◽

Large Predators

There is growing recognition that humans may mediate the strength and nature of the ecological effects of large predators. We took advantage of ongoing gray wolf (Canis lupus Linnaeus, 1758) recolonization in Washington, USA, to contrast adult survival rates and sources of mortality for mule deer (Odocoileus hemionus (Rafinesque, 1817)) and white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) in areas with and without wolf packs in a managed landscape dominated by multiple human uses. We tested the hypothesis that the addition of wolves to the existing predator guild would augment predator-induced mortality rates for both ungulates. Source of mortality data from adult mule deer and white-tailed deer, respectively, revealed that wolf-related mortality was low compared with that inflicted by other predators or humans. Predator-caused mortality was largely confined to winter. There was little effect of wolf presence on adult deer mortality rates, and there was no difference in mortality between the two deer species relative to wolf-free or wolf-occupied sites. Although this study occurred early in wolf recovery in Washington, our results differ from those demonstrated for gray wolves in protected areas. Thus, we encourage further investigation of effects of direct predation by recolonizing large carnivores on prey in human-dominated landscapes.

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Diet of Grey Wolves (Canis lupus) During Calving in a Moose– Caribou System in Northern Ontario

The Canadian Field-Naturalist ◽

10.22621/cfn.v131i3.1822 ◽

2018 ◽

Vol 131 (3) ◽

pp. 215-220

Author(s):

Rob Found ◽

Ashley A. D. McLaren ◽

Arthur R. Rodgers ◽

Brent R. Patterson

Keyword(s):

Canis Lupus ◽

Rangifer Tarandus ◽

Castor Canadensis ◽

Northern Ontario ◽

Southern Limit ◽

Proximate Cause ◽

Declining Populations ◽

Dietary Component ◽

A Minor ◽

The Impact

Grey Wolves (Canis lupus) are a leading proximate cause of declining populations of Woodland Caribou (Rangifer tarandus), a threatened species. Although predation on adult caribou has been well documented, less is known about predation on neonatal calves. We used scat analysis to examine the diet of wolves in an area of Ontario overlapping the receding southern limit of caribou occurrence. Wolves consumed mostly Moose (Alces americanus; 82.7%), followed by American Beaver (Castor canadensis; 10.9%), caribou (3.1%), and Snowshoe Hare (Lepus americanus; 1.5%). This low use of caribou is consistent with other evidence suggesting that caribou are a minor dietary component of wolves in this system; however, because most caribou consumption consists of calves, the impact on this slowly reproducing species may still be significant.

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