bluuebunny/crossref_metadata_2025 huggingface dataset:
Stand-level Attributes of Snowshoe Hare (Lepus americanus) Habitat in a Post-Fire Trembling Aspen (Populus tremuloides) Chronosequence in Central Yukon
Authors: Strong Wayne L. , Jung Thomas S.
Published: January 2017

Large-scale fires are anticipated to increase in frequency in the boreal forest under global climate warming scenarios. To understand concomitant responses by wildlife to fire-induced habitat changes, fecal pellet counts were used to assess Snowshoe Hare (Lepus americanus) use of four age-classes of boreal forest after fire in central Yukon, Canada. Use of stands across a chronosequence of 8–177 years was bimodal. Post-fire Trembling Aspen (Populus tremuloides) stands ≤20 years old had greater densities of Snowshoe Hare pellets (median 156 pellets/dam2) than Trembling Aspen stands 21–70 years old, mixedwood stands 71–120 years old (<17 pellets/dam2), or Western White Spruce (Picea albertiana) -dominated stands 121–170 years old (71 pellets/dam2). Forty stand-level compositional and structural variables were assessed as possible predictors of Snowshoe Hare pellet densities. Multidimensional scaling was used to identify variables (n = 10) that were most strongly related to pellet densities and was followed by multiple regression. Canopy cover of Trembling Aspen <50 cm tall and Western White Spruce ≤1 m tall, and deadfall depth, in combination, were the best estimators of Snowshoe Hare pellet densities among stands in the chronosequence (P <0.001, 64.5% variance explained). Although Trembling Aspen <50 cm tall explained the most variance, its canopy cover did not exceed 10%. More Trembling Aspen cover <50 cm tall and greater deadfall depths within the chronosequence were associated with stands ≤20 years old. Peak Snowshoe Hare use occurred in early (≤20 years old) rather than mid-successional (21–120 years old) stands, contrary to use patterns reported elsewhere. The lack of tall understory shrubs likely limited the use of mid-successional stands.
Predicting the Spread of Purple Loosestrife (Lythrum salicaria) in the Prairies
Authors: Lindgren Cory J. , Walker David
Published: January 2017

Purple Loosestrife (Lythrum salicaria) is an invasive plant introduced into North America in the early 1800s. It has since spread into the prairie provinces of Canada (Manitoba, Saskatchewan, and Alberta). It invades wetland habitats, marshes, riparian areas, and natural areas, and it outcompetes native wetland vegetation. In this study we modelled the potential distribution of Purple Loosestrife in the Prairies, explored which suites of predictive variables produced the best ecological niche models, and explored two different approaches to the partitioning of data in evaluating models. We used a number of performance measures and expert evaluation to select our best models. The best model was developed using a suite of climate variables and growing degree-days as the predictive variables and by partitioning testing and training data using stratified random sampling. The model indicated that Purple Loosestrife has not yet reached its full potential distribution in the Prairies. The modelling techniques presented in this paper may be used to predict the potential distribution of other emerging invasive plants, and the results can be used to optimize early detection and surveillance strategies for Purple Loosestrife in areas of the Prairies.
Cougars, Puma concolor, in Ontario: Additional Evidence
Authors: Mallory Frank F. , Carter Rebecca A. , Fortier Jenny L. , Kenn I. Stuart , Weis Linsay , White B. N.
Published: January 2017

Recent evidence suggests that the Cougar (Puma concolor) has returned to New Brunswick, Quebec, Manitoba, and Ontario. An abundance of sightings have been reported for many decades throughout south-central Ontario, but genetic confirmation has been confounded by a lack of carcasses or DNA. In this paper, we identify (1) genetic evidence of a single Cougar in the wild of Ontario, (2) a gene (cytochrome b) and methodology to distinguish the Cougar from other mammals in Ontario using scats, hair follicles, and soft and hard tissue, and (3) a gene that can distinguish individual Cougars from each other and would distinguish populations of subspecies if they exist in Ontario. Potential Cougar scats and other tissue samples were collected from across Ontario, and hair snares baited with catnip and carnivore lure were placed in locations where Cougar sightings were frequent, near Sudbury, Ontario. We analyzed samples for mtDNA, and one scat sample from the Wainfleet Bog Conservation Area, Port Colborne, Ontario, was positive for Cougar. Evidence from archeological data and Cougar sightings suggests that the historical range of Cougars extended in Ontario from the Great Lakes–St. Lawrence Ecotone south, primarily associated with the Eastern Deciduous Forest Biome and the primary prey of the Cougar, the White-tailed Deer (Odocoileus virginianus) and the North American Elk (Cervus elaphus). The data suggest that Cougar distribution has moved north in recent times due to clear-cutting, along with their primary prey. Further studies of Cougar presence in the province are warranted.
Taxonomic Implications of Morphological and Genetic Differences in Northeastern Coyotes (Coywolves) (Canis latrans × C. lycaon), Western Coyotes (C. latrans), and Eastern Wolves (C. lycaon or C. lupus lycaon)
Authors: Way Jonathan G.
Published: January 2017

The eastern Coyote or Coywolf (Canis latrans × C. lycaon) inhabiting northeastern North America resulted from hybridization between the expanding population of the western Coyote (Canis latrans) and the remnant population of Eastern Wolf (C. lycaon) and possibly domestic dogs (C. lupus familiaris) in the early 20th century. This study compares the body mass of eastern (i.e., northeastern) Coyotes, western Coyotes, and Eastern Wolves and synthesizes the recent literature to gain better insight into the taxonomic relations and differences of closely-related Canis species. Northeastern Coyotes (males = 16.5 kg; females = 14.7 kg) were statistically (P < 0.0001) intermediate in mass between western Coyotes (males = 12.2 kg; females = 10.7 kg) and Eastern Wolves (males = 28.2 kg, females = 23.7 kg), consistent with their hybrid origin, but were numerically closer to western Coyotes. Large Cohen’s d (3.00–8.56), (0.915–0.929), and Cohen’s f (3.28–3.62) values indicated large effect sizes from the body mass comparisons. Eastern Wolves were 61–71% heavier than the same sex in the northeastern Coyotes, which in turn were ca. 35–37% heavier than the same sex in the western Coyotes. Alternatively, western Coyotes were 73–74% of the size of the same sex in the northeastern Coyotes, which in turn were 59–62% of the size of the same sex in the Eastern Wolves. I also attempted to relate mitochondrial DNA (mtDNA) haplotypes to body mass. Six of 17 (35.3%) adult female northeastern Coyotes captured in Massachusetts weighed ≥18 kg, heavier than any other described Coyote from outside northeastern North America. Mitochondrial DNA haplotypes associated with these heavy female northeastern canids were C9 = 4, C19 = 1, and C48 = 1. Body mass (kg) and mtDNA haplotype data of 53 northeastern Coyotes (males = 28, females = 25) showed no difference between haplotype and body mass for males (P < 0.852) or females (P < 0.128), suggesting that there is not a particular haplotype (e.g., C1) that is associated with the heavier animals. I propose that the most appropriate name for this hybrid animal is Coywolf (Canis latrans × C. lycaon), rather than a type of Coyote. Coywolves are distinct, being larger than any other population of Coyotes but smaller than Eastern Wolves. I propose that the 5 distinct types of Canis be recognized as: western Coyote, Coywolf (northeastern Coyote), Eastern Wolf (including Red Wolf C. rufus), Gray × Eastern Wolf hybrids (‘Great Lakes’ Wolves; C. lupus × C. lycaon or C. lycaon × C. lupus), and Gray Wolf (C. lupus). The implications for wolf recovery in the northeastern United States is discussed.
The response of invertebrate populations in three undisturbed soils in southwestern Ontario, Canada, to variations in local soil properties, seasonal changes, and climate
Authors: Harris Ian W. E.
Published: January 2017

Three distinctly different undisturbed mature forested sites at the northern limits of the Carolinian forest system in Lambton County, Ontario, were examined to test the hypothesis that the abundance of each order of soil invertebrates captured is dependent on a unique set of soil properties, seasonal changes, and climate variations. Sixteen independent variables were recorded over five consecutive years. With the exception of rainfall, air temperature, and soil temperature, means of the measured variables differed significantly (P < 0.05) among soils. Twenty-eight taxa of invertebrates were captured, of which Acari, Collembola, and Nematoda were most abundant. Only the mean of total abundance and the mean abundance of Acari, Nematoda, and Haplotaxida differed significantly (P < 0.05) among soils. Haplotaxida was the only taxon in all three soils found to be influenced significantly (P < 0.05) by seasonal variation. The usual mid-summer minimum in the abundance of Haplotaxida was latest and most clearly defined in the clay soil and earliest and least clearly defined in the sand soil. Regression analysis showed that each site is sufficiently separated in the factor space observed that the abundance of each invertebrate taxon is dependent on different combinations of local variables. The hypothesis was rejected.
Golden Eagles (Aquila chrysaetos) breeding in Wapusk National Park, Manitoba
Authors: Asselin N. C. , Scott M. S. , Larkin J. , Artuso C.
Published: January 2017

The North American subspecies of the Golden Eagle (Aquila chrysaetos) is of conservation concern throughout Canada. The species is not currently known to breed in Manitoba. In 2011 and 2012, during the course of surveys in Wapusk National Park of Canada in northeastern Manitoba, seven pairs of Golden Eagles and one sub-adult were observed. The identification of nests in proximity to three pairs, the presence of an adult at one nest, and visible white down feathers on two nests confirm breeding and extend the breeding range of the Golden Eagle into Manitoba, where breeding was previously uncertain. The three occupied nests were 14 km (n = 2) and 31 km (n = 1) from the nearest adjacent occupied nest identified. Foraging on Canada Goose (Branta canadensis) goslings was observed. Further research is needed to determine the overall nest density and the diet of Golden Eagles in northeastern Manitoba.
Impact of the rust Puccinia linkii on Highbush Cranberry, Viburnum edule, near Smithers, British Columbia
Authors: Daust Kiri
Published: January 2017

The berries of Highbush Cranberry (Viburnum edule) are an important food source for wildlife and for people in rural areas. In 2012 and 2013, many Highbush Cranberry plants in northwestern British Columbia were unusually severely infected by the rust Puccinia linkii, with telia covering up to half of each leaf. Given the ecological importance of the overwintering berries, I studied the impact of the infection on the production and quality of berries in mixed forests near Smithers, British Columbia. Sites where Highbush Cranberry bushes were infected with the rust had significantly more undeveloped berries. Plants from sites with higher levels of infection produced berries with significantly less sugar. Dead leaf tissue was also significantly more prevalent in infected plants. This study provides evidence that Puccinia linkii may stress plants, leading to reduced quality and quantity of berries, especially if the severity of the infection increases with the increasingly moist springs that are projected for the region.
Density and abundance of the Freshwater Pearl Mussel, Margaritifera margaritifera, in the Kennebecasis River, New Brunswick and evidence of recent recruitment
Authors: Sollows M. C. , McAlpine Donald F. , Munkittrick K. R.
Published: January 2017

Freshwater Pearl Mussel, Margaritifera margaritifera (L., 1758) populations are endangered or threatened throughout Europe, and those in eastern Canada are believed to be some of the most abundant populations remaining worldwide. Although M. margaritifera occurs widely in Atlantic Canada, there is little information to allow its conservation status in the region to be assessed or to place these populations in a global context. Using 0.25 m2 survey quadrats, maximum densities of M. margaritifera in six mussel beds on the Kennebecasis River and a tributary in southeastern New Brunswick were found to range from 12 to 200 m-2. Mean densities at the five mainstem sites ranged from to 1.9 m-2 (SE±0.4) to 16.0 m-2 (±4.3). Mean density on the tributary stream was 1.2 m-2 (SE±0.7). Abundance of M. margaritifera at the six sites ranged from 4,536 (SE±2,600) to 55,520 (SE±14,768) and together the six mussel beds supported an estimated 161,315 Freshwater Pearl Mussels. The presence of juvenile M. margaritifera as small as 11.5 mm at the most upstream site, and Freshwater Pearl Mussels <30 mm at all sites, indicates that there had been recruitment of M. margaritifera juveniles in the Kennebecasis River in the 4–6 years prior to the 2007–2008 study.
Melanistic diversity in the Maritime Gartersnake, Thamnophis sirtalis pallidulus, in Nova Scotia, Canada
Authors: Gilhen John , Scott Fred W.
Published: January 2017

We describe an unusual diversity of melanistic conditions in populations of the Maritime Gartersnake, Thamnophis sirtalis pallidulus, in Nova Scotia: pure melanism, melanism, nigrismus (predominantly melanistic), abundismus (mosaic melanism). This variability is widespread in Nova Scotia, and it includes coastal islands.
Apparent widespread decline of the Boreal Chorus Frog (Pseudacris maculata) in eastern Ottawa
Authors: Seburn David C. , Gunson Kari , Schueler Frederick W.
Published: January 2017

The Boreal Chorus Frog (Pseudacris maculata) was once common in the eastern Ottawa area. To assess its current status, we conducted auditory surveys at 184 wetlands in 2011 and 2012. Boreal Chorus Frogs were heard at only five (2.7%) of the surveyed sites. These five sites were spatially aggregated, with only 0.5–7.5 km between any two sites. Sites occupied by Boreal Chorus Frogs in eastern Ottawa were surrounded by significantly greater agricultural cover (at 1.0-, 1.5-, and 2.0-km radii), less forest cover (1.0- and 2.0-km radii), and less wetland cover (1.5- and 2.0-km radii) than occupied sites in western Ottawa. Sites in eastern Ottawa that were apparently unoccupied were surrounded by significantly greater agricultural cover (only at the 2.0-km radius), similar forest cover (all radii), and less wetland cover (all radii) compared with occupied sites in western Ottawa. Boreal Chorus Frog populations are commonly subject to extirpation resulting from stochastic events. The reduced wetland cover in eastern Ottawa may be accompanied by reduced wetland connectivity, making recolonization of wetlands difficult or impossible. Our data do not show whether wetland connectivity has been reduced, but future research should address this important topic.
Cues used by predators to detect freshwater turtle nests may persist late into incubation
Authors: Riley Julia L. , Litzgus Jacqueline D.
Published: January 2017

Previous studies have found that turtle nest depredation is concentrated immediately post-oviposition, likely because cues alerting predators to nest presence are most obvious during this time. In Algonquin Provincial Park, Ontario, we examined the frequency of nest depredation during the incubation period for Snapping Turtles (Chelydra serpentina [Linnaeus, 1758]) and Midland Painted Turtles (Chrysemys picta marginata [Agassiz, 1857]). Contrary to most past findings, nest depredation occurred throughout the incubation period for both species. In fact, 83% and 86% of depredation interactions with Snapping and Painted Turtle nests, respectively, occurred more than a week after oviposition at our study site. Peaks in nest depredation (weeks with ≥10% nest depredation) occurred late in incubation and may have coincided with hatching. Trail cameras deployed at four nesting sites revealed six predator species interacting with nests. The presence of predators at nest sites increased late in the incubation period indicating a persistence or renewal (from hatching) of cues; additional research is necessary to determine the nature of these cues. These findings have implications for both research and turtle conservation. Further research should examine the relationship between temporal changes in predator species’ density and patterns of nest depredation. Additionally, in areas where protective nest caging is used as a species recovery action, it may be important to ensure that cages remain in place throughout the incubation period until emergence of hatchlings.
Muskrat (Ondatra zibethicus) interference with aquatic invertebrate traps
Authors: Cavallaro Michael C. , Main Anson R. , Morrissey Christy A.
Published: January 2017

In field biology, interactions between wildlife and in situ equipment occur often. These interactions have the potential to induce a variety of behaviours in local fauna. Here, we note the destructive behaviour exhibited by the Muskrat (Ondatra zibethicus) following deployment of aquatic invertebrate traps for research purposes at 12 wetlands located in central Saskatchewan. Of 24 aquatic insect emergence traps used on seven wetlands in our study, 14 (58%) required recurring repairs. In addition, on several occasions, leaf litter bags and their anchoring stakes were torn or chewed. The recurring damage took place in wetlands with Muskrat lodges. We recommend structural modifications to aquatic invertebrate traps in wetland complexes densely inhabited by Muskrats and other semi-aquatic rodents.
Mortality of Common Eider, Somateria mollissima (Linnaeus, 1758), and other water birds during two inshore oiling events in southeastern Newfoundland, 2005 and 2006
Authors: Robertson Gregory J. , Gilliland Scott G. , Ryan Pierre C. , Dussureault Johanne , Power Kyran , Turner Bruce C.
Published: January 2017

Although the waters off Newfoundland harbour millions of wintering marine birds, chronic marine oil pollution has been repeatedly reported. Unusually high numbers (hundreds) of oiled birds were noted following two events in March 2005 and April 2006 in southeastern Newfoundland. Common Eiders (Somateria mollissima [Linnaeus, 1758]) were the main victims in the first event, with at least 1400 affected, based on retrieval of carcasses and aerial surveys. The April 2006 event affected 19 species; Common Eiders were again the most numerous with a minimum of 337 birds oiled. Among the Common Eiders affected in both events, most were the northern type, including the borealis (C. L. Brehm, 1824) subspecies and presumed intergrades between borealis and dresseri Sharpe, 1871. Coupled with the legal harvest, these oiling events may have had an effect on the wintering Common Eider population. Alcids, other sea ducks, loons and gulls were also oiled, but in low numbers (< 100); thus, their populations were not likely affected by these events.
Late-winter habitat use by the Fisher, Pekania pennanti (Erxleben, 1777), in the Boreal Plains Ecozone of northwestern Saskatchewan, Canada
Authors: Proulx Gilbert
Published: January 2017

Late-winter habitat use by the Fisher, Pekania pennanti (Erxleben, 1777) in northwestern Saskatchewan was assessed in February 2009, 2011, and 2012. A total of 78 Fisher tracks were recorded over 60 300 m of snowshoe surveys. Fisher tracks were significantly less frequent than expected in Tamarack (Larix laricina [Du Roi] K. Koch) stands with > 40% crown closure and mainly 0–10 m trees (P < 0.05) and in open areas. Fishers used other habitat types equal to availability, including muskeg and coniferous, mixed, and deciduous forest stands. Maintaining mosaics of forest stands of different seral stages interspersed with muskeg would meet the late-winter habitat needs of Fishers in the Boreal Plains Ecozone of northwestern Saskatchewan.
The enigma of the 10-year wildlife population cycle solved? Evidence that the periodicity and regularity of the cycle are driven by a lunar zeitgeber
Authors: Archibald Herbert L.
Published: January 2017

Despite nearly 100 years of research, the periodicity and regularity of the 10-year wildlife population cycle remain an enigma. This paper presents the hypothesis that the 9.3-year nodal half-cycle of the moon is the zeitgeber (“time-giver”) of the 10-year wildlife population cycle. The period of the population cycles of the Snowshoe Hare (Lepus americanus) and Ruffed Grouse (Bonasa umbellus) is close to 9.3 years. These wildlife cycles have stayed closely in phase with the 9.3-year nodal half-cycle for 150 years. Population density of the Snowshoe Hare and Ruffed Grouse is inversely related to a 9.3-year cycle of the moon's tidal force. There is also a 9.3-year cycle of “nights without darkness” at the equinoxes, in which the full moon rises before sunset and sets after sunrise the following morning in certain years. Snowshoe Hare and Ruffed Grouse cycles are positively correlated with this phenomenon. The nodal cycle provides explanations for the key features of the 10-year wildlife cycle: regularity, periodicity, amplitude, distribution, and synchrony. Population models based solely on the nodal cycle account for 62% of the variation in the Canada Lynx (Lynx canadensis) cycle and 37% in the Ruffed Grouse cycle. The mechanism(s) by which herbivore cycles might be entrained by the lunar nodal cycle could involve a cyclic effect on factors including predation, stress, photoperiod, phenology, temperature, cloudiness, ultraviolet B radiation, cosmic rays, and food plant quality.
Cory’s Bittern, Ixobrychus “neoxenus” exilis: morph, mutant, or mixed bag?
Authors: Smith Paul
Published: January 2017

Cory’s Bittern (Ixobrychus “neoxenus” exilis) is an enigmatic form, usually referred to as a rare dark colour phase or morph of Least Bittern (Ixobrychus exilis [Gmelin, 1789]). A review of the literature indicates that birds identified as Cory’s Bittern show considerable plumage variation and commonly exhibit multiple plumage anomalies. Temporal and spatial clumping of records shows that they are of irregular occurrence; thus, they do not meet the criteria for recognition as a colour morph. Cory’s Bittern should thus be viewed as a colloquial name that refers to any one of a number of abnormally dark-plumaged, genetically undefined and phenotypically heterogeneous Least Bitterns.
Use of a marsh dominated by the introduced European Lake Sedge, Carex acutiformis, by highly localized native butterflies
Authors: Catling Paul M. , Kostiuk Brenda
Published: January 2017

To determine whether native butterflies had colonized a marsh in Ottawa that was entirely dominated by the invasive alien European Lake Sedge (Carex acutiformis), we surveyed two adjacent stands of the sedge and surrounding habitats. Dion Skipper (Euphyes dion), Mulberry Wing (Poanes massasoit), Broad-winged Skipper (P. viator), and browns (Lethe spp.) were all abundant in the introduced sedge, but absent from surrounding habitats. This is the first report of the use of invasive-dominated wetland by native Canadian butterflies. Reduced nectar resources because of dominance of the invasive species over native nectar-producing plants did not prevent significant colonization. The known restriction of the butterflies to native Lakebank Sedge (Carex lacustris) as a larval host plant, but its absence in the area, coupled with dominance of its close relative, European Lake Sedge, provides strong circumstantial evidence of the use of the latter as larval food. This report doubles the number of recently localized native butterflies that have been able to increase their distribution by switching to habitat dominated by invasive plants.
The flora of Cunningham Inlet, Somerset Island, Nunavut: history, analysis, and new collections of vascular plants, mosses, lichens, and algae
Authors: Sokoloff Paul C.
Published: January 2017

New collections of vascular plants, bryophytes, lichen, and algae are reported for Cunningham Inlet on the north coast of Somerset Island, Nunavut. This list of 48 species of vascular plants, 13 bryophytes, 10 lichens, and five algae includes 136 specimens collected in 2013 and 39 previously unreported specimens from the National Herbarium of Canada at the Canadian Museum of Nature (CAN), Agriculture and Agri-Food Canada’s Vascular Plant Herbarium (DAO), and University of Alberta (ALTA). Ten vascular plants from previous collecting in 1958 are re-reported here to give a comprehensive account of the vascular plant flora of the region. Two vascular plants are recorded for the first time for Somerset Island: Smooth Draba (Draba glabella Pursh) and Edlund’s Fescue (Festuca edlundiae S. G. Aiken, Consaul & Lefkovitch).
Subspecific identification of the Great Lakes' first Brown Booby (Sula leucogaster) using DNA
Authors: Skevington Jeffrey H. , Pawlicki James , Kelso Scott , Kerr Kevin C.R. , Jacklin Marcie
Published: January 2017

The first Brown Booby (Sula leucogaster) recorded in the Great Lakes basin was discovered on Lake Erie near the source of the Niagara River on 7 October 2013 by J. P. Morphologic evidence suggested that this bird was an adult female of the nominate Atlantic subspecies. We obtained genomic DNA from feces left by the bird. Mitochondrial DNA from the control region (CR2) was sequenced and compared with extensive CR2 data for Brown Booby available in GenBank; this corroborated the morphologic hypothesis. This is the first time that a vagrant bird in Canada has been identified using DNA extracted from feces.
Diurnal and nocturnal activity patterns of invasive Wild Boar (Sus scrofa) in Saskatchewan, Canada
Authors: Stolle Kathryn , Van Beest Floris M. , Vander Wal Eric , Brook Ryan K.
Published: January 2017

The Wild Boar (Sus scrofa) is invasive in western Canada and poses a significant ecological and socio-economic threat over much of the country. We sought to quantify their presence and to determine when they are most active and whether their activity patterns are influenced by group size. Digital trail cameras (n = 18) were placed in a stratified design in the four most dominant habitat types of central Saskatchewan, Canada, and activated between December 2011 and June 2013 for a total of 5715 trap-days. In 71,175 photographs, we obtained 22 individual visits of Wild Boars to the trail cameras. We found no differences in activity between night (1900–0700; 59% of all detections) and day (0701–1859; 41% of detections), and we did not detect any effect of group size. Ongoing monitoring will be required to determine changing activity patterns in response to changing hunting pressure as Wild Boar continue to expand across Canada.
Mass mortality of Northern Map Turtles (Graptemys geographica)
Authors: Catrysse Jordan , Slavik Emily , Choquette Jonathan , Leifso Ashley E. , Davy Christina M.
Published: January 2017

We report a mass mortality of Northern Map Turtles (Graptemys geographica [LeSueur, 1817]) on the north shore of Lake Erie, Ontario, Canada. Thirty-five dead adult females were recovered from a nesting area over a period of four weeks. Predation and boat strikes were both excluded as potential cause of death, but the actual cause could not be determined because of the poor condition of the carcasses. Other possible explanations for the mortality include poisoning, drowning, and infection with an unidentified pathogen. Mass mortality in long-lived species, such as turtles, can have long-term effects on population growth and is a cause for concern in a species at risk.
The Canada Lynx (Lynx canadensis) of Isle Royale: over-harvest, climate change, and the extirpation of an island population
Authors: Licht Daniel S. , Moen Ron A. , Brown D. Paul , Romanski Mark C. , Gitzen Robert A.
Published: January 2017

In the 1930s, the Canada Lynx (Lynx canadensis) was extirpated from Isle Royale, a 535-km2 island located in western Lake Superior, 22 km from the Ontario and Minnesota shorelines. The first half of the 20th century was a time of change on Isle Royale as Caribou (Rangifer tarandus) disappeared, Coyotes (Canis latrans) briefly appeared, Moose (Alces americanus), Grey Wolves (Canis lupus), and Red Foxes (Vulpes vulpes) became established, and the habitat was altered by fire, logging, and over-browsing. Although these changes may have contributed to the demise of the Canada Lynx, our results suggest that over-harvest was a primary cause. Assuming a peak carrying capacity of 75 Canada Lynx and harvest rates comparable to those reported from 1890–1935, a population viability analysis indicated that the island population had a 0% chance of surviving 50 years. The analysis also indicated that, even in the absence of harvest, the population had only a 14% chance of persistence for 250 years. However, when 10 Canada Lynx were added to the modeled population every 10th year, the probability of persistence increased to 100%. Our analyses suggest that the island’s Canada Lynx population maintained itself by periodic immigration across an ice bridge; therefore, natural recolonization should be possible. However, the probability of ice-bridge formation has declined from 0.8 in the winter of 1958–59 to 0.1 in 2012–13, likely as a result of climate change. The Isle Royale situation exemplifies another impact of climate change and the possible need to augment populations to mitigate the loss of connectivity.
Kleptoparasitism by Bald Eagles (Haliaeetus leucocephalus) as a factor in reducing Peregrine Falcon (Falco peregrinus) predation on Dunlin (Calidris alpina) wintering in British Columbia
Authors: Dekker Dick , Drever Mark C.
Published: January 2017

Kleptoparasitism, or food piracy, is common in a wide range of taxa, particularly among predators, with the larger species forcing smaller species to surrender their catch. The Bald Eagle (Haliaeetus leucocephalus) is known to rob Peregrine Falcons (Falco peregrinus) of just-caught prey. We present time series of kleptoparasitic interactions between eagles and peregrines hunting Dunlin (Calidris alpina) that were wintering at Boundary Bay in the Fraser River valley, British Columbia. In 1108 hours of observation during January, intermittently between 1994 and 2014, we recorded 667 sightings of Peregrine Falcons, including 817 attacks on Dunlin resulting in 120 captures. The population of wintering Bald Eagles in the study area increased from about 200 in 1994 to 1800 in 2014, while the rate of kleptoparasitism at the expense of peregrines increased from 0.05 to 0.20. The increase in the number of Bald Eagles coincided with a decline in January sightings of Peregrine Falcons, which suggests that some falcons may have left the study area because of interference from eagles. The decrease in Peregrine Falcon numbers can be expected to have led to reduced predation risk for Dunlins. Christmas Bird Counts conducted in the Fraser River Valley have underscored the fluctuation in eagle and peregrine numbers reported here.
Apparent extirpation of prey fish communities following the introduction of Northern Pike (Esox lucius)
Authors: Nicholson Michele E. , Rennie Michael D. , Mills Kenneth H.
Published: January 2017

We examined the long-term effects on prey fish communities of introducing Northern Pike (Esox lucius), a top predator fish, into small, Boreal Shield lakes lacking natural piscivore populations. During 1987–1994, Northern Pike were introduced into Lakes 110, 221, and 227 in the Experimental Lakes Area in northwestern Ontario, Canada. In Lake 227, prey fish were undetectable three years after the addition of Northern Pike. Although Northern Pike were removed from the lake by 1996, multiple independent visual and trapping surveys have yielded no evidence of any fish in Lake 227 since then. In 1994–1995, 85% of the Northern Pike were removed from Lake 221. In 2012, despite intensive sampling efforts using baited minnow traps, fyke nets, trap netting, gill netting, angling, and visual observation, no forage fish of any species was observed or caught in Lake 110 or 221. In all three lakes where Northern Pike were added, prey fish populations were extirpated or too small to detect. In Lake 221, we estimated the current population of Northern Pike to be 49 ± 37, a 59% decrease since 2000 when prey fish were still present. The mean total length and body condition of Northern Pike in Lake 221 had not changed since the prey community collapsed. Our findings suggest that the introduction of Northern Pike into lakes without natural piscivore populations has long-lasting effects on fish community structure, to the detriment of both Northern Pike and prey fish populations.Note: an erratum for this article was published in the subsequent issue, and is attached to the end of this article's pdf. Table 2 had not been justified properly; the revised table corrects this issue.
Record long-distance movement of a Deer Mouse, Peromyscus maniculatus, in a New England montane boreal forest
Authors: Wood Connor M. , McKinney Shawn T.
Published: January 2017

We report a single-season, non-homing movement of 4287 ± 10 m by an adult male Deer Mouse, Peromyscus maniculatus, in western Maine, United States, in summer 2014. The movement was achieved in two stages: 927 ± 3 m in four days and an additional 3360 ± 10 m in 44 days. This is approximately 40% greater than the previously documented maximum linear movement for an individual of this species.
Great Plains Ladies’-tresses (Spiranthes magnicamporum) in the lower Great Lakes region and a new record for New York State
Authors: Brunton Daniel F.
Published: January 2017

Six populations of Great Plains Ladies’-tresses (Spiranthes magnicamporum Sheviak) have recently been discovered in three locations east of the lower Great Lakes region of Canada and the United States. The possible occurrence of S. cernua × magnicamporum hybrids was detected at one New York site. These discoveries are from both natural alvar and disturbed meadow and shore sites. The new records suggest that S. magnicamporum occurs more widely than was suspected previously, its presence perhaps masked by its similarity to the common S. cernua (L.) Richard. Eastern occurrences may represent a combination of post-glacial relict populations, responses to climate change, and the results of long-distance dispersal events. These range extensions constitute the most easterly known populations of S. magnicamporum in North America. They also represent new records for New York State (including Jefferson and St. Lawrence Counties) and for the City of Ottawa in Ontario.
Do ducks and songbirds initiate more nests when the probability of survival is greater?
Authors: Grant Todd A. , Shaffer Terry L.
Published: January 2017

Nesting chronology in grassland birds can vary by species, locality, and year. The date a nest is initiated can influence the subsequent probability of its survival in some grassland bird species. Because predation is the most significant cause of nest loss in grassland birds, we examined the relation between timing of nesting and nest survival. Periods of high nest survival that correspond with the peak of nesting activity might reflect long-term adaptations to specific predation pressures commonly recurring during certain periods of the nesting cycle. We evaluated this theory by comparing timing of nesting with date-specific nest survival rates for several duck and passerine species breeding in north-central North Dakota during 1998–2003. Nest survival decreased seasonally with date for five of the seven species we studied. We found little evidence to support consistent relations between timing of nesting, the number of nest initiations, and nest survival for any species we studied, suggesting that factors other than nest predation may better explain nesting chronology for these species. The apparent mismatch between date-specific patterns of nest survival and nest initiation underscores uncertainty about the process of avian nest site selection driven mainly by predation. Although timing of nesting differed among species, the general nesting period was fairly predictable across all years of study, suggesting the potential for research activities or management actions to be timed to take advantage of known periods when nests are active (or inactive). However, our results do not support the notion that biologists can take advantage of periods when many nests are active and survival is also high.
Aspen parkland pasture altered by Richardson’s Ground Squirrel (Urocitellus richardsonii Sabine) activity: the good, the bad, and the not so ugly?
Authors: Newediuk Levi J. , Waters Isobel , Hare James F.
Published: January 2017

Although Richardson’s Ground Squirrels (Urocitellus richardsonii) are considered pests throughout their North American range, their impact on forage in Canadian aspen parkland has not been explored. We investigated the effect of Richardson’s Ground Squirrel density on forage quality and plant community composition in an intensely grazed cattle pasture in the aspen parkland region of Manitoba, Canada. We detected no significant differences in forage protein content or legume, grass, and litter biomass among ground squirrel density levels. However, ground squirrel density did influence the abundance of invasive and forage plant species; greater squirrel density reduced the prevalence of Smooth Brome (Bromus inermis Leysser) and Red Clover (Trifolium pratense L.) and increased the abundance of Quackgrass (Elymus repens (L.) Gould) and Black medick (Medicago lupulina L.). Plant community diversity also increased with ground squirrel density. There were no differences in soil bulk density or ammonia content among squirrel density levels; however, soil nitrate content was highest at low ground squirrel density. Changes in available soil nitrogen and relative abundances of forage species on this pasture may affect cattle diet by altering both the availability and quality of forage. Our findings highlight the need for further investigation of the role of Richardson’s Ground Squirrel on rangeland in the aspen parkland region to ascertain the generality of the effects documented in our study. Until such effects and their implications for cattle production are understood, land managers should refrain from exterminating colonies of Richardson’s Ground Squirrel.
Distribution of the exotic Pond Slider (Trachemys scripta) in Ontario
Authors: Seburn David C.
Published: January 2017

The Pond Slider (Trachemys scripta) is a turtle native to the eastern United States, but, because of its popularity in the pet trade, it now occurs in many countries around the world as a result of escapes and the release of unwanted pets. The distribution of the Pond Slider in Ontario is reviewed based on 393 records obtained from various sources. Sliders have been reported from 130 spatially distinct sites in 35 districts. The Toronto area accounts for 67% of records, and more than 80% of reports are from urban areas. Pond Slider reports date back to the 1950s, but 63% of records are from 2010 or later. Sliders have been observed in Ontario during all months of the year except December. Sliders have bred in Ontario, but the spatial extent of successful reproduction remains unknown.
Response of wild Trumpeter Swan (Cygnus buccinator) broods to wetland drawdown and changes in food abundance
Authors: Lumsden Harry G. , Thomas Vernon G. , Robinson Beren W.
Published: January 2017

A brief period of drawdown can stimulate wetland productivity and enhance the attractiveness of a site for breeding Trumpeter Swans (Cygnus buccinator) by providing a nutrient pulse. Drawdown of a pond in Aurora, Ontario, lasting about 8 weeks in late summer and fall 2009 followed by re-flooding increased the abundance of invertebrates, especially snails, in the following year. This response was ephemeral, lasting 1 year. Wild Trumpeter Swans and their cygnets responded by selective feeding the year after drawdown, despite the risk of predation by Snapping Turtles (Chelydra serpentina). There was a strong correlation between the feeding activity of two cygnets and the local abundance of snails in the pond in 2010. The nutritional content, especially protein, calcium, phosphorus, and magnesium, of a variety of abundant foods satisfied the requirements for skeletal growth and development and was higher than that of available commercial duck grower rations. The responsive feeding behaviours of the cygnets are typical of specific appetitive behaviour and suggest that swans rapidly exploit unpredictable nutrient fluxes in their local environment.
Influence of Environmental Variables on the Diel Movements of the Greenland Shark (Somniosus microcephalus) in the St. Lawrence Estuary
Authors: Gallant Jeffrey J. , Rodriguez Marco A. , Stokesbury Michael J.W. , Harvey-Clark Chris
Published: January 2017

The geographic distribution of the Greenland Shark (Somniosus microcephalus) extends from the Arctic Ocean to the North Atlantic Ocean. However, little is known about the habitat of this species, as it is generally found at great depths or in the High Arctic. In the St. Lawrence Estuary, Greenland Sharks undertake diel vertical movements into shallow water (≤ 30 m), but the reasons for these movements are unknown. To test the hypothesis that environmental variables drive the movements of this shark in the St. Lawrence Estuary, eight Greenland Sharks were tagged with acoustic telemetry transmitters during the summer of 2005. Three environmental factors, temperature, light, and tides, were associated with their movements. Movement patterns indicate a preference for deep, cold water during daylight hours and shallow, warmer water during the night. Ascending into shallow water mostly coincided with darkness and high tide. This improved understanding of the spatio-temporal distributionof the Greenland Shark will allow for assessment of the risk to these sharks from commercial fisheries, as occurs in the Greenland Halibut (Reinhardtius hippoglossoides) longline fishery. In addition, temperature-driven behavioural patterns may change as the thermal structure of the water column shifts due to global warming.
Cougars (Puma concolor) Killed by North American Porcupines (Erethizon dorsatum)
Authors: Elbroch L. Mark , Hoogesteijn Rafael , Quigley Howard
Published: January 2017

Predation is inherently risky, and Cougars (Puma concolor) are occasionally injured while hunting prey. Between 2001 and 2015, we documented the cause of death of 59 Cougars (22 subadults and 37 adults) in the Southern Yellowstone Ecosystem, Wyoming. Here we report on 2 animals (9% of subadult mortalities) killed as a result of complications after hunting North American Porcupines (Erethizon dorsatum). We also report an observation of a Cougar killed in Venezuela by quills of a Prehensile-tailed Porcupine (Coendou prehensilis). Porcupines may kill and wound more Cougars than previously suspected and may be an important cause of mortality, at least for subadult animals.
Evidence of Predation on Nestling Birds by Eastern Gartersnakes (Thamnophis sirtalis sirtalis)
Authors: Halliday William D.
Published: January 2017

Diet is an important aspect of the natural history of all animals, but diet can vary through space and time because of variations in prey availability. The diet of the Common Gartersnake (Thamnophis sirtalis) consists mainly of earthworms and frogs, but other prey items might be important when they are locally abundant. I report an observation of a female Eastern Gartersnake (Thamnophis sirtalis sirtalis) regurgitating 2 nestling birds in Ottawa, Ontario, Canada. Birds are seldom present in the diet of the Common Gartersnake. This rare food choice highlights the opportunistic nature of foraging by adult Common Gartersnakes and, further, demonstrates that diet depends not only on prey preference, but also on prey availability.
First Record of the Land Snail Pristiloma idahoense (Gastropoda: Pristilomatidae) for Montana
Authors: Hendricks Paul
Published: January 2017

The land snail Pristiloma idahoense (Pilsbry, 1902) is reported from Montana for the first time. Five live individuals were found under downed wood beneath a mature coniferous forest canopy at 1670 m elevation in the Big Creek drainage of the Bitterroot Mountains, Ravalli County, Montana. This location extends the known range approximately 75 km east and over the crest of the Bitterroot Mountains from the nearest sites in Idaho County, Idaho and supports the hypothesis that the terrestrial mollusc fauna of Montana west of the continental divide has been strongly influenced by a molluscan radiation, which developed in a northern Idaho Pleistocene refuge. The probable route of dispersal for P. idahoense between the Bitterroot Mountains of Montana and the adjacent Lochsa River drainage of Idaho was over the lower mountains to the north in the Lolo Pass area.
Keeping quality of beef sausage using ethanolic extract of gamma-irradiated pomegranate peel powder
Authors: Mohammed Ibrahim , Hassanien Fawzy , El Sahy , Afify Mohammed , Mohammed Abdeldaiem
Published: January 2017

The present study aims to evaluate the antioxidant and antibacterial activity
of ethanol extracts from gamma-irradiated pomegranate (Punica granatum) peel
powder (PE) at the dose levels of 0, 3, 6, and 9 kGy. The ?ntioxidant
activity of the extracts was estimated using the radical scavenging activity
against 2,2?-diphenyl-1-picrylhydrazyl (DPPH?), ?-carotene/linoleic acid
bleaching system, and ferric reducing antioxidant power (FRAP). Antibacterial
activity of the extracts was assessed against Bacillus cereus, Staphylococcus
aureus, Escherichia coli, Klebsilla penumoneae, Pseudomonas aeruginosa, and
Salmonella typhumurium. The results showed that PE treated with 6 kGy had a
higher content of total phenolic compounds (TPC), total flavonoid compounds
(TFC), and antioxidant activity. Hence, the PE of 6 kGy-irradiated peels were
selected to be added to beef sausage. Different concentrations of 6
KGy-irradiated PE were applied to improve beef sausage hygienic quality and
extend the shelf life during cold storage (4?C). The results indicated that
when 12 mL of the extract were added to one kg of beef sausage, the
shelf-life of the sausage was extended from 15 days to 50 days (at 4?C),
compared with the control, without changes of the microbiological, chemical,
and sensory attributes.
Enzymatic hydrolysis of extruded soybean meal at high substrate concentrations
Authors: Sharikov Anton , Sereda Anna , Kostyleva Elena , Velikoretskaya Irina , Polyakov Victor
Published: January 2017

Extrusion as a pretreatment before enzymatic hydrolysis of soybean meal is an
effective technique to eliminate antinutritional properties of the main
thermostable soy proteins glycinin and ?-conglycinin for production of feed
ingredients with enhanced properties. In terms of economic efficiency,
biotechnological processes are preferable to carry out at high substrate
concentrations. The aim of the investigation was to evaluate the influence of
high substrate concentrations in the range of 26-32% and enzyme dosages
(0.4 - 3.1 PU/g) on efficiency of hydrolysis of extruded toasted soybean meal
with bacterial protease. The results showed that maximum degree of hydrolysis
was 42.1% at the enzyme dosage of 3.6 PU/g and at the substrate concentration
of 29.0%. The increase in the substrate concentration had a strong effect on
the deterioration of dynamic viscosity of the hydrolysates from 0.2 to 5.82
Pa?s. A combination of extrusion cooking at 120?C and enzymatic treatment
with ?Protolad B? protease enabled hydrolysis of glycinin and ?-conglycinin
to peptides with molecular mass below 15 kDa.