White Wolf Research Articles

Egg sac parasitism of Arctic wolf spiders (Araneae: Lycosidae) from northwestern North America

Abstract Parasitoids can have significant impacts on the life history of their hosts, as well as on local population and community dynamics. These effects could be particularly pronounced in the Arctic where the breeding season is short. We studied the incidence and loads of egg sac parasitoids, and whether these varied with body size or among species in three Arctic wolf spider species: Pardosa sodalis Holm 1970, Pardosa lapponica (Thorell 1872) and Pardosa moesta Banks 1892 from the Yukon Territory in northwestern Canada. We found a high incidence of egg sac parasitism (by Gelis sp.) and that the incidence of parasitism increased significantly with body size in two of the spider species; however, it did not change in the largest species. Among the three species investigated, parasitism was highest in the largest species (P. sodalis). Parasitism loads ranged from one to fourteen individuals per egg sac, and incidence reached 29.6% overall in P. sodalis. Parasitism may have significant impacts on the life...

An Account of the Taxonomy of North American Wolves From Morphological and Genetic Analyses

AbstractThe available scientific literature was reviewed to assess the taxonomic standing of North American wolves, including subspecies of the gray wolf, Canis lupus. The recent scientific proposal that the eastern wolf, C. l. lycaon, is not a subspecies of gray wolf, but a full species, Canis lycaon, is well-supported by both morphological and genetic data. This species' range extends westward to Minnesota, and it hybridizes with gray wolves where the two species are in contact in eastern Canada and the Upper Peninsula of Michigan, Wisconsin, and Minnesota. Genetic data support a close relationship between eastern wolf and red wolf Canis rufus, but do not support the proposal that they are the same species; it is more likely that they evolved independently from different lineages of a common ancestor with coyotes. The genetic distinctiveness of the Mexican wolf Canis lupus baileyi supports its recognition as a subspecies. The available genetic and morphometric data do not provide clear support for the recognition of the Arctic wolf Canis lupus arctos, but the available genetic data are almost entirely limited to one group of genetic markers (microsatellite DNA) and are not definitive on this question. Recognition of the northern timber wolf Canis lupus occidentalis and the plains wolf Canis lupus nubilus as subspecies is supported by morphological data and extensive studies of microsatellite DNA variation where both subspecies are in contact in Canada. The wolves of coastal areas in southeastern Alaska and British Columbia should be assigned to C. lupus nubilus. There is scientific support for the taxa recognized here, but delineation of exact geographic boundaries presents challenges. Rather than sharp boundaries between taxa, boundaries should generally be thought of as intergrade zones of variable width.

Life changes as polar regions thaw

Summary Spiders and shrubs grow bigger, while ice shields are shrinking. Climate change is already affecting biotopes in both polar regions, while scientists are trying to establish what is happening and why. Michael Gross reports.

Growth in Skull Length and Width of the Arctic Wolf: Comparison of Models and Ontogeny of Sexual Size Dimorphism

We compared four classical nonlinear growth curves (Gompertz, Logistic, Richards, and von Bertalanffy) in modeling observed skull condylobasal length and zygomatic width as a function of age in wild arctic wolves (Canis lupus arctos). We analyzed gender-specific growth patterns and the ontogeny of sexual size dimorphism in this species as revealed by the best model from these alternatives. For both genders and skull size measurements, the size-at-age data provided the best support for the von Bertalanffy model because of higher fitting degrees, lower root mean squared standard deviation of data points about the fitted growth curve, Akaike weight of 37.4% or higher, and fewer parameters derived directly from metabolic laws. Male asymptotic condylobasal length was 3.2% longer, and zygomatic width 4.1% wider, than in females. Sexual size dimorphism in this species develops in part because males grow faster, which might benefit them in terms of reproductive success and the capture and killing of large ungulate prey.

Decline and Extermination of an Arctic Wolf Population in East Greenland, 1899–1939

The decline and extermination of an arctic wolf population in East Greenland between 1899 and 1939 were investigated through analysis of 40 years of archival data, which contained records of 252 sightings of wolves or their tracks. Prior to the start of exploitation by Europeans, this small, isolated wolf population probably consisted of about 38 wolves during an average year. Of 112 wolves sighted in early winter, 31.3% were lone wolves, 23.2% were in pairs, and the rest were in larger groups. Mean pack size was 3.3 wolves, and packs of more than four wolves were rare. The population was concentrated in the central part of its range, making it vulnerable to exploitation by Danish and Norwegian commercial hunters, who exterminated the population. Poison was the primary agent of destruction. There was no evidence that other proposed causes of the decline were influential. This study provided the first evidence of an arctic wolf population that was eradicated and highlights the vulnerability of small, isolated wolf populations to excessive harvest. Wolves in the High Arctic may be particularly vulnerable because of their exceptionally low densities, smaller pack sizes, lower pup production, infrequent reproduction, and insular or disjunct distributions.

Life history of tundra-dwelling wolf spiders (Araneae: Lycosidae) from the Yukon Territory, Canada

We studied populations of three tundra-dwelling wolf spider (Lycosidae) species to determine reproductive trait relationships and developmental timing in the Arctic. We collected 451 Pardosa lapponica (Thorell, 1872), 176 Pardosa sodalis Holm, 1970, and 117 Pardosa moesta Banks, 1892 during summer 2008. We used log-likelihood ratio tests and multiple linear regressions to determine the best predictors of fecundity and relative reproductive effort. Female body size best explained the variation in fecundity and body condition was the best predictor for relative reproductive effort. We tested for a trade-off between the allocation of resources to individual eggs and the number of eggs produced (fecundity) within each species using linear regression. There was variation in detectable egg size and number trade-offs among sites and these may be related to local variation in resource allocation linked to density-related biotic or abiotic factors. These findings contribute to knowledge about the fitness of arctic wolf spiders in the region of study and are particularly relevant in light of the effects that climate changes are predicted to have on the arctic fauna.

Invasion of eastern Greenland by the high arctic wolf Canis lupus arctos

AbstractThe high arctic wolf Canis lupus arctos was exterminated from eastern Greenland during the 1930s by commercial hunters and was considered absent for 40 years. In this study, I examined the recolonisation of east Greenland by wolves from north Greenland through an invasion that began in 1979. The invasion successfully led to the establishment of a new population, because a wolf pair arrived into the core historical wolf range followed by one or two wolves during the next four years. Weight of evidence suggested that the invaders arrived into east Greenland through unintentional, human‐mediated jump dispersal. I present two cases of long‐distance dispersals by lone wolves following military sled patrols in northern Greenland. Wolves had likely failed to establish a viable population in east Greenland for 40 years for the following reasons: 1) a low propagule pressure, 2) invasions were high risk, occurring through vast areas of the lowest, large ungulate prey biomass reported for wolves in North America, and 3) only singletons made it into eastern Greenland.

Updated paleomagnetic pole from Cretaceous plutonic rocks of the Sierra Nevada, California: Tectonic displacement of the Sierra Nevada block

We report remanent magnetization measurements from 13 sites in Cretaceous plutonic rocks in the northern Sierra Nevada (38°N–39.5°N). By increasing the number of available paleomagnetic sites, the new data tighten constraints on the displacement history of the Sierra Nevada block and its pre-extensional position relative to interior North America. We collected samples in freshly exposed outcrops along four highway transects. The rocks include diorite, granodiorite, and tonalite with potassium-argon ages (hornblende) ranging from 100 Ma to 83 Ma. By combining our results with previous paleomagnetic determinations from the central and southern Sierra Nevada (excluding sites from the rotated southern tip east of the White Wolf–Kern Canyon fault system), we find a mean paleomagnetic pole of 70.5°N, 188.2°E, A 95 = 2.6° ( N = 26, Fisher concentration parameter, K = 118). Thermal demagnetization indicates that the characteristic remanence is generally unblocked in a narrow range within 35 °C of the Curie temperature of pure magnetite. Small apparent polar wander during the Cretaceous normal-polarity superchron, plus prolonged acquisition of remanence at the site level, may account for the low dispersion of virtual geomagnetic poles and relatively large K value. Tilt estimates based on overlapping sediments, stream gradients, and thermochronology of the Sierra Nevada plutons vary from 0° to 3° down to the southwest. Without tilt correction, the mean paleomagnetic pole for the Sierra Nevada is essentially coincident with the North American reference pole during the Cretaceous stillstand (125 Ma to 80 Ma). At 95% confidence, the apparent latitude shift is 1.1° ± 3.0° (positive northward), and the apparent rotation is negligible, 0.0° ± 4.7°. Correcting for each degree of tilt, which is limited to 3° on geologic evidence, increases the rotation anomaly 2.2° counterclockwise, while the apparent latitude shift remains unchanged.

Insular and disjunct distribution of the Arctic wolf in Greenland, 1978–1998

Little research has been conducted on the spatial and temporal distribution of wolves in the High Arctic, and the processes that influence distributional patterns are not well understood. The present study addressed this information void in north and east Greenland by determining bi-seasonal distribution patterns and core areas based upon 303 sightings of wolves or their tracks during 1978–1998. The data suggested that this wolf population were predominantly distributed in semi-isolated patches in an insular and disjunct distribution. Evidence of wolf occurrence in some areas was so irregular that wolves should be considered absent in most years. Where such areas were clustered over several hundreds of kilometers, they collectively constituted areas of general wolf absence that could be considered gaps in distribution. There was no evidence that this population functioned in a mosaic of closely, interlocking pack territories similar to those reported in lower latitudes. The observed distributional pattern likely reflected the exceptionally impoverished and fragmented polar desert and semi-desert habitat that compelled wolves to adopt differing spatial distribution patterns relative to wolves in temperate areas. The broader scientific significance of this study is that, even in the most remote, vast, and uninhabited regions, it is possible to produce meaningful results on distributional patterns of rare, terrestrial carnivores that can serve as foundation for the next generation of testable hypotheses.

The Keepers' Tattoo (review)

Reviewed by: The Keepers' Tattoo Kate Quealy-Gainer Arbuthnott, Gill. The Keepers' Tattoo. Chicken House/Scholastic, 2010. [432p.] ISBN 978-0-545-17166-3 $17.99 Reviewed from galleys R Gr. 7-10. When the Shadowmen come to Nyssa's small island village, life as Nyssa knows it changes completely. Her foster father informs her that she bears the mark of the Keepers, a legendary people who, while once responsible for the prosperity of the Archipelago, are now hunted by the island nation's current despot, Alaric (known as the White Wolf), for their knowledge of an ancient spell. Fleeing her home with an uncle, Nyssa soon uncovers more secrets from her past, including the fact that her twin brother, once thought dead, is actually alive—as Alaric's personal slave. To save the people she loves, Nyssa ventures into the Wolf's lair not once but twice, each time bringing the tattooed words that potentially spell out Alaric's ultimate victory—or defeat, depending on who reads them. A taut, compelling fantasy that explores the blurred power dynamics of perception and reality, Arbuthnott's debut novel will please fans of Le Guin and McKinley with its rich characterizations and haunting setting. A world marked by destruction and loss, the Archipelago is revealed ruin by ruin in spare, eloquent language. Similarly, Nyssa and company are scarred by their individual pasts, making this less a story about a resourceful heroine and more a portrayal of the attempts of one family (albeit a makeshift one) at healing and reinvention. While the pacing falters at points, the ever-present shadow of the Wolf makes for a palpable tension that imbues even the quieter scenes with a sense of urgency. Both the human drama and the larger mystery of the Keepers' Legend will keep readers turning the pages. Copyright © 2010 The Board of Trustees of the University of Illinois

Climate change and altitudinal variation in sexual size dimorphism of arctic wolf spiders

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 41:259-265 (2010) - DOI: https://doi.org/10.3354/cr00855 Climate change and altitudinal variation in sexual size dimorphism of arctic wolf spiders Toke Thomas Høye1,*, Jörg U. Hammel2 1Department of Wildlife Ecology and Biodiversity, National Environmental Research Institute, Aarhus University, Grenåvej 14, 8410 Rønde, Denmark 2Institute of Systematic Zoology and Evolutionary Biology with Phyletic Museum, Friedrich-Schiller-University Jena, Erbertstr. 1, 07743 Jena, Germany *Email: toh@dmu.dk ABSTRACT: Climate change is advancing the onset of the growing season, and this is happening at a particularly fast rate in the Arctic. Although this has recently been shown to affect the sexual size dimorphism (SSD) of a wolf spider species through time, it remains to be shown whether spatial variation in the physical environment is similarly affecting SSD. We studied altitudinal variation in adult body size of male and female wolf spiders on Disko Island, West Greenland. Two species exhibited female-biased SSD (measured by carapace width) at sea level but not at higher altitudes. Males and females of a third species were of equal size at both altitudes, and the 2 remaining species found on Disko Island were only present at 1 low altitude site each. Altitudinal variation in SSD is probably a result of sex differences in body size response to shorter growing seasons with altitude. Our results suggest that climate change may result in increased SSD. Constraints on body size may increase with altitude, and expanding growing seasons due to climate change may predominantly affect SSD at higher altitudes. Such intra-specific effects of climate may be widespread and suggest that further research in this topic is needed. KEY WORDS: Body size · Carapace width · Climate impacts · Intra-specific variation · Lycosidae Full text in pdf format Supplementary material PreviousCite this article as: Høye TT, Hammel JU (2010) Climate change and altitudinal variation in sexual size dimorphism of arctic wolf spiders. Clim Res 41:259-265. https://doi.org/10.3354/cr00855Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 41, No. 3. Online publication date: May 04, 2010 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 2010 Inter-Research.

Possible Use of Foresight, Understanding, and Planning by Wolves Hunting Muskoxen

On Ellesmere Island in 2006, arctic wolves (Canis lupus arctos) were observed making a two-pronged approach to a herd of muskoxen (Ovibos moschatus) and, on another occasion, ambushing muskoxen. Both observations seemed to provide evidence that the wolves were using foresight, understanding, and planning. Although the possible use of insight and purposiveness has been documented in captive wolves, the present report is one of the few to document the possibility that freeranging wolves use these other three mental processes.

Annual Arctic Wolf Pack Size Related to Arctic Hare Numbers

During the summers of 2000 through 2006, I counted arctic wolf (Canis lupus arctos) pups and adults in a pack, arctic hares (Lepus arcticus) along a 9 km index route in the area, and muskoxen (Ovibos moschatus) in a 250 km2 part of the area near Eureka (80° N, 86° W), Ellesmere Island, Nunavut, Canada. Adult wolf numbers did not correlate with muskox numbers, but they were positively related (r2 = 0.89; p < 0.01) to an arctic hare index. This is the first report relating wolf numbers to non-ungulate prey.

Abundance, social organization, and population trend of the arctic wolf in north and east Greenland during 1978–1998

Abundance, social organization, and population trend of the arctic wolf ( Canis lupus arctos Pocock, 1935) in north and east Greenland, 1978–1998, were determined from 353 sightings of 552 wolves by the Danish military, by expeditions, and from 8 consecutive years (1991–1998) of fieldwork. Available evidence suggested that this wolf population consisted of up to 55 wolves in favorable times. Six core packs were identified. Maximum wolf density was estimated at 1 wolf/3745 km2, which appears to be the lowest wolf density reported, representing 3.5% of maximum late winter wolf density in Denali Park, Alaska, and <1% of that in north-central Minnesota. Social organization was characterized by a preponderance of pairs and lone wolves. Mean early winter pack size was 2.6 wolves/pack; the lowest reported for wolves in North America. Packs >4 wolves were rare, constituting 3.8% of early winter sightings. The population increased, on average, 8% per year during the period 1978–1991 and appeared to reach a peak in 1991–1992. These depressed population characteristics are likely the consequence of the lowest ungulate prey availability in North America, e.g., 2.6% of that of wolves in northeastern Minnesota.

Long-Term Control of Peary Caribou Numbers by Unpredictable, Exceptionally Severe Snow or Ice Conditions in a Non-equilibrium Grazing System

The number of Peary caribou (Rangifer tarandus pearyi) on the Queen Elizabeth Islands, Canadian High Arctic, is at an all-time known low. Yet some populations are still hunted, and there is no adequate monitoring program in place to determine the consequences. We evaluate information from the Peary caribou population on the south-central Queen Elizabeth Islands as a standard for an accurate and realistic assessment of what controls Peary caribou population dynamics. Between 1973 and 1997, major population crashes related to severe winter or spring weather are known to have occurred on the south-central Queen Elizabeth Islands in four caribou-years (i.e., 1 July–30 June). Population losses were 67% in 1973–74, 33% in 1994–95, 78% in 1995–96, and 83% in 1996–97. There is no evidence for direct density-dependent responses during either the favorable weather years of population growth or during any one of the years with a disastrous die-off. It appears that Peary caribou on the Queen Elizabeth Islands are living in a non-equilibrium grazing system driven mainly by abiotic factors (emergent properties), particularly by exceptionally unfavorable snow or ice conditions. Changing levels of predation by the High Arctic gray wolf (Canis lupus arctos) compound the uncertainty. In this High Arctic ecosystem, non-equilibrium–governed population dynamics plus wolf predation represents an appropriate conceptual model for Peary caribou populations on the Canadian High Arctic islands. The application of our findings to decision making, together with an adequate monitoring program by the responsible agencies, would promote the biological management and ecological conservation of Peary caribou on the Queen Elizabeth Islands.

Response—How the Gray Wolf Got Its Color

We appreciate and endorse the idea that additional molecular and phenotypic information on natural canid populations will add to our understanding of gene flow and evolutionary histories of domestic dogs and their wild relatives. However, this information could only expand upon, rather than revise, our primary conclusion that the KB allele has been introduced into wolves from dogs. Several lines of independent evidence indicate that KB is “older” in dogs than in Arctic wolves and their descendants in Yellowstone National Park. Extended haplotypes associated with KB are much shorter in dogs than in wolves, more point mutations have accumulated in dog KB than in wolf KB chromosomes, and the worldwide distribution patterns for KB are much broader in dogs than in wolves. Had the ky to KB mutation originated in North American eastern wolves, as Rutledge and colleagues speculate, it is difficult to envision how it could have spread so widely among dog breeds around the world. Thus, even if KB was introduced from eastern to western wolves during the Wisconsin glaciation, KB in eastern wolves would still have been acquired originally from American (in this case, Native American) dogs.

Underworld vs the World of Darkness: Players and Filmgoers Respond to a Legal Battle

Even before its release, Underworld (2003) had proved controversial following a legal action for copyright infringement from White Wolf, a games publisher, and Nancy A Collins, a horror writer. Reaction was marked among White Wolf fans who debated the case in forums on both gaming and film sites. A significant number of fans were deeply critical of the actions of White Wolf, and they were more concerned about being able to see ‘their’ World of Darkness on screen than demonstrating loyalty to the company. This paper will explain the case and examine the reactions of fans at the time.

Consistency of Precariously Balanced Rocks with Probabilistic Seismic Hazard Estimates in Southern California

Abstract The overturning fragility of a freestanding block such as a precariously balanced rock (PBR) has been parameterized as a function of a vector of ground-motion intensity measures. Methodologies are outlined to estimate the failure probabilities of such objects given their residence times. For deterministic seismic hazard analyses (DSHAs), a PBR is exposed to the scenario earthquakes that occur during its exposure time providing an estimate of the probability that the PBR survives the ensemble of events. For probabilistic seismic hazard analyses (PSHAs), the PBR overturning fragility is multiplied by the ground-motion occurrence rate from a vector-valued probabilistic seismic hazard analysis (VPSHA), yielding the marginal overturning rate for each ground-motion bin. Summing the marginal rates over all ground-motion bins produces the total overturning rate. For time-independent Poisson-based PSHA estimates, the probability of block failure can be easily calculated as a function of exposure time. This latter method is used to test VPSHA estimates similar to the 2002 U.S. Geological Survey (USGS) National Seismic Hazard Maps via PBR residence times. PBR overturning fragilities are estimated at sites in southern California near the San Andreas fault, between the San Jacinto and Elsinore faults, and near the White Wolf fault. The resulting failure probabilities for several of the PBRs are very high, suggesting that they are inconsistent with the 2002 USGS ground motions. An investigation of the hazard calculated with zero aleatory variability in the ground-motion prediction equations (GMPEs) suggests that the median ground motions or the earthquake rupture rates are too high at certain PBR sites.

Reproduction and Mortality of the High Arctic Wolf, <em>Canis lupus arctos</em>, in Northeast Greenland, 1978-1998

Reproduction and mortality of the High Arctic Wolf (Canis lupus arctos) in northeast Greenland were investigated through a temporal and spatial analysis of data on litter sizes from direct counts of pups during 21 years (1978-1998). A minimum of 22 pups were produced in a total of six areas. Overall mean litter size was 2.0 pups/litter. This was the lowest mean litter size recorded for Wolves in North America through observations of pups in summer and was probably related to low availability and vulnerability of ungulate prey. Pack size and litter size were very strongly positively correlated. Large packs (4-7 adults) produced significantly more pups than smaller packs. Mean maximum litter size from 17 North American studies employing similar methods, suggested that maximum productivity of wolves in Greenland was 58% below that of wolves elsewhere. The number of Wolf pups born in North America was negatively correlated with increasing latitude. Eight mortalities were identified and were predominantly caused by humans despite the fact that this Wolf population inhabits a national park with year-round protection.

Double Marking in Arctic Wolves, <em>Canis lupus arctos</em>: Influence of Order on Posture

Double marking by Arctic Wolves (Canis lupus arctos) was recorded by Mech (2006) from a pack on Ellesmere Island, Nunavut, Canada, during 16 summers between 1986 and 2005. Using his data on the frequency of occurrence for each of the four postures used by Wolves for urine marking (males – raised leg and stand urinations; females – flexed leg and squat urinations), the probabilities of occurrence for each of eight possible double mark sequences were determined and compared with observed frequencies. Females were somewhat but not significantly more likely to initiate double mark sequences. There was no evidence for any bias in the posture used to initiate a double mark sequence, but assertive postures by both males and females nearly always completed the sequence, occurring much more often than expected by chance.