Wolf response to two kinds of barriers in an agricultural habitat in Spain

2005 ◽  
Vol 83 (2) ◽  
pp. 312-323 ◽  
Author(s):  
Juan Carlos Blanco ◽  
Yolanda Cortés ◽  
Emilio Virgós

We examined the effect of two kinds of barriers on an expanding gray wolf, Canis lupus L., 1758, population in an agricultural habitat in north-central Spain. The barriers were (i) a four-lane fenced highway along a flat area without wildlife-crossing facilities, and (ii) the River Duero Artery (RDA), comprising the river itself (50–100 m wide) and several small infrastructures along it. From March 1997 to October 2001, all 4 radio-collared wolves living <15 km from the highway (1 adult territorial male, 1 territorial breeder female, 1 dispersing male, and 1 female in 3 periods of her life (territorial immature, disperser, and territorial breeder) crossed it on between 4% and 33% of 45–163 monitoring days via vehicle bridges. Moreover, 4 more highways that we monitored in areas without radio-collared wolves have not delayed expansion of the increasing wolf population, suggesting that these highways are not an important barrier for wolves in our study area. In contrast, only 3 of 8 wolves radio-collared <5 km from the RDA were detected crossing it, and 2 of those 3 started to cross it only after severe habitat disturbance; in addition, the RDA seems to have delayed wolf expansion for some 15 years, which suggests that it is a semipermeable barrier for wolves. We discuss the likely consequences of the RDA on the recovery of the Iberian wolf population.

2020 ◽  
Vol 133 (4) ◽  
pp. 343-351
Author(s):  
L. David Mech ◽  
Shannon M. Barber-Meyer

This article synthesizes information from over a six-decade period of studies of White-tailed Deer (Odocoileus virginianus) use of a winter yard and subject to Gray Wolf (Canis lupus) predation in northeastern Minnesota. It also adds spring migration data from 35 adult female deer and fawns studied there during 1998, 1999, 2001, 2014, and 2017. Twenty-nine of these deer migrated in spring a mean distance of 29 km (SE = 4), a maximum distance of 78 km, and at a mean bearing of 83° (SE = 12; range 21–348). These findings are similar to those from 49 deer (both sexes) from the same yard studied during 1974–1984, that migrated a mean distance of 25 km (SE = 1.8) and a mean bearing of 77° ± 4 SE. Between the two periods, the wolf population fluctuated considerably, the winter range of deer in the area where these deer spent summer greatly diminished, and both derechos and fires disturbed the habitat. This study attests to the selective advantage of the migratory tradition of deer in this yard.


2007 ◽  
Vol 85 (2) ◽  
pp. 295-300 ◽  
Author(s):  
V.E. Sidorovich ◽  
V.P. Stolyarov ◽  
N.N. Vorobei ◽  
N.V. Ivanova ◽  
B. Jędrzejewska

Gray wolf ( Canis lupus L., 1758) population fluctuations in northern Belarus (Vitebsk region) between 1990 and 2003 were significantly affected by hunting pressure by humans. Mean litter size was inversely density dependent and varied from 4.8 to 7.7 pups (range 2–10). The increase in litter size with declining density of wolf population concerned only female pups, whereas the number of male pups in a litter was not related to population density. The sex ratio of pups varied significantly: the proportion of females reached 70% in a low-density wolf population and declined to 40%–50% in a high-density population. The age structure also varied. In years following heavy hunting pressure, 55% of individuals shot were juveniles <1 year old (with a strong predominance of females that constituted 69% of juveniles shot), and only 11% of wolves were older than 4 years. The mean age of all wolves shot was 1.5 years. In years following low hunting pressure, 34% of animals shot were juveniles and 20% exceeded 4 years. The mean age was 2.8 years. A female-biased sex ratio of wolf pups conforms to Hiraiwa-Hasegawa’s hypothesis of the advantaged daughter, proposed for species in which mothers are able to influence the reproductive success of their daughters through transmission of rank.


2010 ◽  
Vol 88 (2) ◽  
pp. 129-138 ◽  
Author(s):  
L. D. Mech

The taxonomic identity of the historical and current wolf ( Canis lupus L., 1758 or Canis lycaon Schreber, 1775 or their hybrids) population in Minnesota (MN) and the Great Lakes region has been, and continues to be, controversial. So too does its legal status under the U.S. Endangered Species Act. This review summarizes the morphological and genetic information about that population and concludes that historically the MN population consisted of a gray wolf (C. lupus) in the west and an eastern type ( Canis lupus lycaon or C. lycaon) in the east with intergrades or hybrids between the two in most of the state. After extirpation in much of its original MN range, the now-recovered population was infused with gray wolves from Ontario but still consists of hybrid lycaon × gray wolves, probably with higher content gray wolves in the west and higher content lycaon in the east but with most wolves morphologically appearing to be gray wolves. Because the current Wisconsin and Michigan wolf population was derived from MN wolves, they would be primarily hybrids as well. Future research should seek to relate genetic data with morphological measurements in MN wolves. In addition, attempts to breed coyotes ( Canis latrans Say, 1823) with gray wolves in captivity would shed considerable light on the controversy over the origin and taxonomic identity of the newly proposed C. lycaon.


2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Lily M. Eeden ◽  
Sergey Rabotyagov ◽  
Morgan Kather ◽  
Carol Bogezi ◽  
Aaron J. Wirsing ◽  
...  

2021 ◽  
pp. 106887
Author(s):  
J Cerdeira ◽  
C Castaño ◽  
JF Pérez ◽  
JL Marcos-Beltrán ◽  
R Guerra ◽  
...  

2011 ◽  
Vol 125 (2) ◽  
pp. 158 ◽  
Author(s):  
A. David M. Latham ◽  
Stan Boutin

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.


2010 ◽  
Vol 60 (3) ◽  
pp. 249-257
Author(s):  
Xu-Guang Liu ◽  
Zhi-Zhong Zhang ◽  
Yun-Hai Zhang ◽  
Yun-Sheng Li ◽  
Fu-Gui Fang ◽  
...  

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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