bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphology and development of the egg case in the parasitic copepod Haemobaphes intermedius Kabata, 1967 (Copepoda: Pennellidae)
Authors: Roth Myron
Published: March 2009

Studies on the morphology of the egg sacs of the copepod parasite Haemobaphes intermedius Kabata, 1967 indicate that a distinctive change in appearance occurs once the egg sac is mature and ready to hatch. Highest rates of infection by copepodids occur where adults are found, suggesting a one-host life cycle. Clinocottus acuticeps is recorded as a new host for H. intermedius, as well as for Holobomolochus sp. and Clavella sp. The ecology of the tide pool is discussed in relation to intertidal fish parasites.
Song pitch – habitat relationships in white-throated sparrows: cracks in acoustic windows?
Authors: Waas Joseph R.
Published: March 2009

I compared the hypothesis that birds singing from song posts above 1–2 m should sing in as low a pitch as possible regardless of habitat type, with the traditional "acoustic window" hypothesis which argues that selection favours an inverse relationship between song pitch and foliage density. Songs of white-throated sparrows, Zonotrichia albicollis, were obtained from four habitats which could be arranged in a gradient of foliage density. The pitch of these songs was found to be inversely related to the density of foliage in the habitat occupied, consistent with the acoustic window hypothesis. Significant pitch variation occurred not only between open and forest habitats, but also between mixed and boreal forest habitats. I distinguish between hypotheses that could explain support for the traditional hypothesis despite recent data suggesting that low pitched sound travels best regardless of habitat at song post heights used by white-throated sparrows (5–10 m). I conclude that the acoustic window model may make the right prediction for the wrong reason in white-throated sparrows. I emphasize the need to define and test the assumptions of models before the models themselves are accepted on the basis of support for their predictions.
Plasticity in length of hindgut segments of white-tailed deer (Odocoileus virginianus)
Authors: Weckerly Floyd W.
Published: March 2009

Plasticity in lengths of small intestines, caeca, and large intestines was examined in free-ranging adult white-tailed deer (Odocoileus virginianus) from Tennessee, U.S.A. Using cube root of body mass as a covariate, relative lengths of caeca and large intestines varied significantly among seasons, with segments being shortest in fall and longest in summer. The greatest single season increase for caeca (32%) and large intestines (25%) was from fall to winter. Lengths of hindgut segments of lactating and nonlactating females from summer were not statistically different. Analysis of intestinal segments during winter from three sites representing a gradient in forage quality (fiber content) also showed no statistical difference. Seasonal changes in lengths of intestines appear to reflect historical differences in food quantity and quality between fall and winter, increases in metabolism in spring and summer, and changing nutritional needs of the animal across all seasons. The lack of variation in hindgut segments within seasons suggests that intestinal length is under stronger genetic than environmental control.
Influence of age and territory quality on the reproductive behaviour of male Yellow Warblers
Authors: Studd Michael V. , Robertson Raleigh J.
Published: March 2009

Individual male Yellow Warblers (Dendroica petechia) exhibit differences in their level of parental investment, which correlate with the amount of brown streaking on the breast. We tested two alternative hypotheses to explain these patterns. The age effect hypothesis proposes that the variation in plumage and parental behaviour is an effect of differences in male age. This was tested by analyzing the nest visit rates and plumage scores of banded males present in the study in more than 1 year. The age effect hypothesis is rejected because there was no evidence of significant within-male variation due to increasing age, nor of any consistent directional change in either parental effort or plumage pattern between years. The territory quality hypothesis proposes that the quality of territory occupied has an important proximate influence on male parental effort. By observing the same territories over different years we were able to compare nest visit rates of different males with different plumage scores while holding the effect of territory quality constant. Analysis of variance revealed that male plumage rank had a highly significant effect on nest visit rate, while the effect of territory occupied was not significant. Rejection of these two alternative hypotheses provides further support for the hypothesis that phenotypically different males are using alternative and irreversible lifetime reproductive strategies.
Population composition of humpback whales, Megaptera novaeangliae, on Silver Bank, 1984
Authors: Mattila David K. , Clapham Phillip J. , Katona Steven K. , Stone Gregory S.
Published: March 2009

Between 14 February and 19 March 1984, 19 d were spent observing humpback whales, Megaptera novaeangliae, on Silver Bank. In total, 317 whales were individually identified from photographs of ventral fluke patterns. Comparison of these photographs with the North Atlantic humpback whale catalogue revealed that 97 of the whales had previously been observed in other areas. Matches were made with all of the major known high-latitude feeding grounds: Greenland (6), Newfoundland – Labrador (43), the Gulf of St. Lawrence (7), and the Gulf of Maine (12). Matches were also made with habitats in the winter range of this population: Bermuda (1), Silver Bank in other years (26), Puerto Rico (18), Virgin Bank (1), and Anguilla Bank (1). Analysis of matches suggests that whales from the various high-latitude feeding stocks mix randomly on Silver Bank. Seven surface-active groups contained whales from different high-latitude feeding stocks, providing the strongest evidence to date for genetic mixing among these stocks. The behavior and composition of surface-active groups are discussed. Overall, the number of whales, calves, and surface-active groups observed during this study confirms the apparently singular importance of Silver Bank to the breeding ecology of western North Atlantic humpback whales.
Avian community response to small-scale habitat disturbance in Maine
Authors: Derleth Eric L. , McAuley Daniel G. , Dwyer Thomas J.
Published: March 2009

The effects of small clearcuts (1–8 ha) on avian communities in the forest of eastern Maine were studied using point counts during spring 1978 – 1981. Surveys were conducted in uncut (control) and clear-cut (treatment) plots in three stand types: conifer, hardwood, and mixed growth. We used a mark –recapture model and its associated jackknife species richness estimator [Formula: see text], as an indicator of avian community structure. Increases in estimated richness [Formula: see text] and Shannon–Weaver diversity (H′) were noted in the treated hardwood and mixed growth, but not in the conifer stands. Seventeen avian species increased in relative abundance, whereas two species declined. Stand treatment was associated with important changes in bird species composition. Increased habitat patchiness and the creation of forest edge are hypothesized as causes for the greater estimates of richness and diversity.
Serotonin, but not dopamine or octopamine, modifies locomotor and phototaxic behavior of the crab, Carcinus maenas
Authors: McPhee M. J. , Wilkens J. L.
Published: March 2009

During daylight hours, shore crabs (Carcinus maenas) are strongly photonegative and spend most of the time (76%) hidden under rocks or buried in the sand. After circulating levels of serotonin in the hemolymph were increased to 10−6 mol∙L−1 photonegative behavior was reduced (32%) and crabs spent most of the time (68%) moving in a more or less nondirected fashion. High doses of serotonin (10−4 mol∙L−1) caused extreme leg flexion. Low or high doses of dopamine and octopamine did not modify posture or phototaxis.
Mammal fleas (Siphonaptera) of Alaska and Yukon Territory
Authors: Haas Glenn E. , Wilson Nixon , Osborne Timothy O. , Zarnke Randall L. , Johnson Loyal , Wolff J. O.
Published: March 2009

Twenty-five taxa (species and subspecies) of mammal fleas were recorded from 127 collections in Alaska. Twenty-one of the taxa were collected in 58 new localities. Ctenophthalmus pseudagyrtes pseudagyrtes Baker is new for Alaska, and Microtus xanthognathus is a new host for this flea. Chaetopsylla tuberculaticeps (Bezzi) was collected north of the Brooks Range for the first time, and in southeastern Alaska it was found breeding in a bear den. Five records of fleas from nests of shrews, voles, and tree squirrels are included, but most collections were from 17 species of wild mammals, two commensal rodents, domestic dog and cat, and man. Six records of six taxa of rodent fleas from Yukon Territory were added. Checklists for Alaska and Yukon Territory and distribution maps for 16 taxa are provided.
Spatial and activity patterns of black rat snakes (Elaphe obsoleta) from radiotelemetry and recapture data
Authors: Weatherhead Patrick J. , Hoysak Drew J.
Published: March 2009

We used 323 capture records collected from 1981 to 1987 and intensive radio-tracking data from 11 individuals studied in 1982 and 1983 to determine spatial and activity patterns of black rat snakes (Elaphe obsoleta) in eastern Ontario. In general the snakes remained in their home ranges (which usually did not include the snakes' hibernating sites) until late September or early October and then moved directly to the communal hibernacula and went below ground. Emergence occurred in late April and early May and most snakes returned to their home ranges without delay. The home ranges of males averaged over three times the size of those of females. Males also moved more often and farther than females. Accurate assessment of these patterns would not have been possible without radiotelemetry. Males were captured more frequently than females during the mating season, although they were most active later in the summer. The peak in captures may be due to males spending more time in open areas (where they were most often captured) during the breeding season because doing so somehow increases their success in locating females. Activity and movement patterns follow quite different patterns in males and females. Male activity may be determined by thermoregulatory factors while females may be affected more by reproduction.
Intraocular muscles of the Canadian river otter and Canadian beaver and their optical function
Authors: Ballard K. A. , Sivak J. G. , Howland H. C.
Published: March 2009

The gross morphology and microscopic anatomy of the ciliary and iris musculature of the Canadian river otter (Lutra canadensis) and Canadian beaver (Castor canadensis) were studied to help evaluate whether either species has an exaggerated accommodative mechanism for use underwater. The intraocular muscles of the otter are of a size and organization indicative of an extreme lens-deforming accommodative ability involving both the ciliary body and iris. By contrast, the intraocular muscles of the beaver eye indicate that accommodation is not significant in this animal. Thus, the intraocular musculature of the class Mammalia is not homogeneous, even within the amphibious mammals. Refractive and corneal measurements on two living river otters confirm that this animal is capable of an accommodative range that can neutralize the loss of corneal refractive power when the eye is in water.
Répartition et déplacements des Dauphins de Commerson (Cephalorhynchus commersonii (Lacépède, 1804)) dans un golfe des îles Kerguelen; données du marquage individuel
Authors: Buffrénil Vivian De , Dziedzic Albin , Robineau Daniel
Published: March 2009

Sixteen Commerson's dolphins were tagged in the Gulf of Morbihan, southeast of the Kerguelen Islands, to specify how they use the available space and to determine the structure of their schools. The dolphins use only a small part (about 5%) of the whole area of the gulf, which is located along the northern coast. Their movements are restricted (less than 10 km in the average); they occur mainly along an east–west axis and, more rarely, along a north–south axis. The schools do not seem to have a definite structure. Seasonal migrations towards the gulf (summer) and out of the gulf (winter) are confirmed. Individuals may return to the gulf from one year to another.
A taxonomy of the marine calanoid copepod genus Pseudocalanus
Authors: Frost B. W.
Published: March 2009

Apparent lack of interspecific morphological differentiation and potential co-occurrence of cryptic species have plagued the scientific study of marine planktonic copepods of the genus Pseudocalanus. This taxonomic analysis of Pseudocalanus, based on material collected throughout the geographical range of the genus, establishes the identities of the previously described species and provides evidence for the existence of three previously unrecognized species. As proposed here, the genus now contains seven species. It is confirmed that interspecific divergence in morphological, meristic, and morphometrical features is unusually weak in Pseudocalanus. Nevertheless, biochemical evidence (presented elsewhere), obtained for six of the seven species, supports the taxonomy proposed here. At least two species of Pseudocalanus were found at most localities within the geographical range of the genus; co-occurrences of three species were common, and the ranges of four species overlap in the eastern Bering Sea and coastal Arctic Ocean.
Factors influencing the growth of Bald Eagles in north central Saskatchewan
Authors: Bortolotti Gary R.
Published: March 2009

Mass and eighth primary growth of nestling Bald Eagles (Haliaeetus leucocephalus) were studied in north central Saskatchewan from 1980 to 1982. There were no significant differences among years for any measure of growth. Clutch size and the relative timing of hatching within each breeding season also had no effect on growth. In broods of two young, second-hatched chicks (C2) grew slower than first-hatched chicks (C1) if the hatching interval between siblings was 2 days rather than 1 day. As both hatching asynchrony and the degree of suppressed growth of C2 were independent of absolute growth rates (and hence presumably food supply), it was unlikely that individual females modified the degree of asynchrony in any adaptive manner. Nestlings raised in an area predicted to have high fish (prey) productivity, given the morphology and chemistry of the lake, grew faster than chicks in an area of lower productivity. Growth rate was significantly correlated with the total mass of prey, but not the number of prey items, delivered to the nests by the parents.
Orientation of rainbow trout (Salmo gairdneri) in normal and null magnetic fields
Authors: Chew G. L. , Brown G. E.
Published: March 2009

In the absence of distinct visual or olfactory cues, adult and juvenile rainbow trout (Salmo gairdneri) showed preferred orientation in the presence of a normal magnetic field. In contrast, fish tested in a null magnetic field showed no directed orientation. These results were obtained in both the presence and absence of a slight (12-cm/s) circular water current. These findings indicate that nonanadromous salmonids, like anadromous forms, are capable of sensing magnetic cues during certain types of spatial activity.
Bighorn lamb mortality: predation, inbreeding, and population effects
Authors: Hass Christine C.
Published: March 2009

Survival of lambs in the population of bighorn sheep (Ovis canadensis) on the National Bison Range, Montana, was less than 25% during 1983 and 1984. Sixty-seven percent of lamb mortality occurred within 3 days of birth; ewe behaviour and recovered remains indicated that coyotes likely accounted for most of the mortality. Herd history, calculated inbreeding coefficients, and the observation of several small, weak lambs implied that inbreeding depression, while probably not a major factor in lamb mortality, may have predisposed some lambs to predation. Lamb production was high (88–96%); in spite of high mortality, population numbers were stable.
Acoustic behaviour of resident killer whales (Orcinus orca) off Vancouver Island, British Columbia
Authors: Ford John K. B.
Published: March 2009

Recordings of underwater vocalizations and behavioural observations were collected from 16 photographically identified resident pods of killer whales (Orcinus orca) off Vancouver Island, British Columbia, during 1978–1983. Vocalizations recorded during 43 days spent with three representative pods were analyzed for each of five activity states: foraging, travelling, group-resting, socializing, and beach-rubbing. The whales produced three types of sounds that were assumed to be social signals: discrete calls, variable calls, and aberrant calls. Discrete calls dominated vocalization in most contexts. An increase in production of variable and aberrant calls was observed during socializing and beach-rubbing activities. Each resident pod had a group-specific repertoire of 7–17 discrete call types (mean = 10.7) that was consistent over a number of years. The relative use of different calls varied with activity, but no call type was correlated exclusively with any behaviour or circumstance that could be identified. Discrete calls probably function as intragroup contact signals to maintain pod cohesion and coordinate activities. Structural modulations of standard call formats and variations in frequencies of call use appear to carry information on the emotional state of vocalizing individuals. Group-specific repertoires of calls may increase the effectiveness and reliability of this contact system and function as indicators of pod affiliation.
The role of bulls in pioneering new habitats in an expanding muskox population on the Seward Peninsula, Alaska
Authors: Smith Timothy E.
Published: March 2009

Muskoxen (Ovibos moschatus) occurred on the Seward Peninsula historically but were rare or extinct at the time of European exploration. The species was reintroduced in 1970 and the population numbered at least 527 animals in 1988. Previous authors concluded that the adult bulls observed away from centers of muskox concentration were lost from the population. Twenty-four male and 15 female muskoxen were radio collared and monitored during 1981–1986 to compare the fate of these mobile animals with those remaining on traditional range and to determine the significance of distant movements to the population. Radio-collared bulls were classified as migratory or sedentary. Success in acquiring harems was compared between these classifications and according to the locations of bulls during breeding periods. Migrating bulls were as successful in acquiring harems over the course of observation as sedentary bulls. Harem bulls were 4–9 years old; older or younger bulls were not successful. Bulls were observed alone or in groups 80 times, whereas cows were observed alone only 5 times and never in groups composed exclusively of cows. Radio-collared bulls occupied remote winter habitat 50% of the winters observed, whereas cows spent only 22% of the winters in remote locations and 67% of these were in association with a radio-collared bull. The migratory strategy is seen as a means to increase a bull's prospect for breeding in years when social competition would preclude his participation in areas of high muskox density. Bulls served as the vanguard for expansion of traditional habitat.
Evidence for and possible causes of increased mortality of bull muskoxen during severe winters
Authors: Gunn Anne , Miller Frank L. , McLean Bruce
Published: March 2009

Muskoxen (Ovibos moschatus) were classified by sex and age at 12 locations on four islands in the Canadian Arctic Archipelago, Northwest Territories. We classified 147 muskoxen on Bailey Point, southwestern Melville Island, and 92 on northeastern Prince of Wales Island in August 1983. We subsequently classified 5449 muskoxen on western Victoria and Banks islands in July–August 1986, which we used as a basis for evaluating the 1983 samples. The pooled sex ratio for muskoxen ≥ 3 years old was significantly skewed toward females, and the proportion of single bulls was also lower on Bailey Point than on northeastern Prince of Wales Island in August 1983 or on Banks or Victoria islands in July–August 1986. Sexual behaviour was frequently observed at Bailey Point in August 1983, which suggests that both bulls and cows were in breeding condition. Almost no aggressive rutting behaviour was seen at Bailey Point, in contrast to observation of the complete range of sexual and aggressive behaviours on Prince of Wales Island. Above-average (1970–1985) snow depths were experienced from March to May in five of the six winters preceding winter 1982–1983. We suggest that severe winters imposed malnutrition-related mortality on spent bulls. The depleted fat reserves of these bulls apparently could not sustain them during severe and prolonged winters. This kind of winter mortality among breeding bulls likely is higher in areas of high muskox densities where more interactions between bulls during the rut lead to greater energetic costs.
The hair follicle density and seasonal shedding cycle of the muskox (Ovibos moschatus)
Authors: Flood Peter F. , Stalker Margaret J. , Rowell Janice E.
Published: March 2009

Descriptions of muskox skin are limited despite the fact that its fine undercoat, commonly known as qiviut, is in increasing commercial use. Accordingly, skin biopsies from two bulls, two castrates, and one nonpregnant female were examined histologically at approximately 1-month intervals between 2.2 and 3.2 years of age. The biopsy sites were all 3 cm from the midline: one was in the midcervical region (the mane), another in the middle of the back (the saddle), and the third midway between the tuber coxae and the tuber ischii (the rump). Following surgical preparation, the biopsies were taken under local analgesia using a sharpened 4-mm stainless steel tube mounted in an electric drill. In addition, miscellaneous skin samples were collected from other sources. A regular pattern of follicles similar to that seen in the domestic sheep was hard to discern though primary follicles were readily identifiable by their size and their association with the duct of a sweat gland. For the three skin areas combined, the ratio of secondary to primary follicles (s/p ratio ± SEM) was 37.3 ± 1.8: 1, about twice that seen in the most improved breeds of sheep. The s/p ratio was slightly less on the saddle than on the neck and rump (P < 0.05). The mean follicle density was 42.8 ± 1.4/mm2, which is similar to that seen in the more highly selected sheep. The density on the neck was a little less than that in the saddle and rump (P < 0.05). Sebaceous glands and apocrine sweat glands are associated with primary follicles. Sebaceous glands are associated with some secondary follicles but sweat glands are not. About 100 sweat glands/cm2 were present.
The banded chromosomes of the muskox (Ovibos moschatus)
Authors: Desaulniers Daniel M. , King W. A. , Rowell Janice E. , Flood Peter F.
Published: March 2009

The muskox (Ovibos moschatus), a member of the family Bovidae, has 48 chromosomes consisting of 12 biarmed and 34 acrocentric autosomes, an acrocentric X chromosome, and a small metacentric Y chromosome. To obtain more information about this species, chromosome preparations from cultured lymphocytes were R-banded, C-banded, or stained with silver nitrate. R-banding was sufficient to identify individual chromosomes. C-banding revealed prominent centromeric bands on all acrocentric chromosomes and very faint staining of the centromeric regions of the biarmed chromosomes. This pattern has been observed in other bovids, such as sheep and water buffalo, which also have biarmed and acrocentric chromosomes. Silver nitrate staining revealed a per metaphase average of 5.23 nucleolus organizer regions, the chromosomal sites of rRNA genes. The nucleolus organizer regions were located on the ends of the long arm of three pairs of submetacentric and two pairs of acrocentric autosomes. Similar numbers of terminally located nucleolus organizer regions have been observed in other bovids such as cattle, sheep, and goats. These results parallel those obtained in other members of the family and emphasize the general cytogenetic similarity within the Bovidae.
The pursuit deterrent function of tail-wagging in the zebra-tailed lizard (Callisaurus draconoides)
Authors: Hasson Oren , Hibbard Richard , Ceballos Gerardo
Published: March 2009

The zebra-tailed lizard (Callisaurus dranconoides) is a small, sit-and-wait predator, which itself is subject to predation by a variety of animals, including other larger lizards. It lives in relatively open, flat habitats, and is well camouflaged. Nevertheless, it has a distinctive black and white banded tail that it exposes by curling and wagging. We demonstrate that tail-wagging is a response to the approach of a potential predator (here, humans). We tested alternative hypotheses regarding the function of this behavior. Our results support the pursuit deterrent hypothesis, namely, that the conspicuous behavior of the lizards is aimed at their predators to communicate the signaler's state of altertness and its relative escape ability, and functions to reduce the likelihood of further pursuit. Alternative hypotheses tested here are not supported. We suggest that such interspecific signals are common in nature.
The effects on small-mammal populations of aerial applications of Bacillus thuringiensis, fenitrothion, and Matacil® used against jack pine budworm in Ontario
Authors: Innes Duncan G. L. , Bendell James F.
Published: March 2009

In late June 1985, both operational and experimental aerial spraying was conducted against an outbreak of jack pine budworm (Choristoneura pinus) in northern Ontario. We report the effects of the insecticides Bacillus thuringiensis, fenitrothion, and Matacil® on populations of rodents and shrews in young (20 years) and medium-aged (40 years) jack pine (Pinus banksiana) plantations. Live, snap, and pitfall traps were used to monitor small-mammal populations from early June to late August on four sprayed plots and two control plots. We found no statistically significant differences in abundances that could be attributed to an insecticide. However, pitfall trapping suggested that the abundance of shrews was altered by the fenitrothion spray. Both the pattern and magnitude of shrew captures was different relative to a control and two other treatment plots. This difference may have resulted from the lack of available prey (arthropods) on the fenitrothion plot. With the exception of fenitrothion, our results agree with other studies which suggest that standard applications of insecticides to control forest insects have no detectable or only limited impact on small mammals.
Survival of certain naturally acquired freshwater parasites of juvenile sockeye salmon, Oncorhynchus nerka (Walbaum), in hosts held in fresh and sea water, and implications for their use as population tags
Authors: Bailey R. E. , Margolis L. , Workman G. D.
Published: March 2009

Sockeye salmon (Oncorhynchus nerka) smolts were captured from the outlet streams of Cultus Lake, British Columbia, in 1985 and 1986, and from Fraser Lake, British Columbia, in 1986. Samples collected in 1985 were reared in salt water. Samples collected from each lake in 1986 were divided equally into two groups: one group was reared in fresh water, the other was maintained in salt water. Initially biweekly, and later monthly, subsamples from each group were examined for seven parasite taxa: Myxidium salvelini, Diplostomulum sp. metacercaria, Phyllodistomum umblae, Eubothrium sp. (immature), Proteocephalus sp. (immature), Neoechinorhynchus salmonis, and Salmincola californiensis. The maximum life-span was greater than the duration of the experiments (32–40 weeks) for all species in hosts reared in fresh water (except for S. californiensis, which was removed from all freshwater hosts). Survival of M. salvelini, P. umblae, and S. californiensis was reduced in hosts reared in sea water. No differences in survival of each of Diplostomulum sp. metacercaria, Eubothrium sp., Proteocephalus sp., and N. salmonis were observed between hosts held in fresh water or salt water. Implications for the use of these parasites as natural tags are discussed.
Use of track transects to measure the relative occurrence of some boreal mammals in uncut forest and regeneration stands
Authors: Thompson I. D. , Davidson I. J. , O'Donnell S. , Brazeau F.
Published: March 2009

Tracks of marten (Martes americana), lynx (Felis lynx), red fox (Vulpes vulpes), ermine (Mustela erminea), snowshoe hare (Lepus americanus), and red squirrel (Tamiasciurus hudsonicus) were censused from 1980 to 1985 on 1-km transects in uncut stands and on eight sites that had been clear-cut between 1 and 33 years ago, in boreal mixedwood habitat near Manitouwadge, Ontario. Marten tracks were more common in uncut areas than in younger stands. Lynx tracks were most abundant on sites that were logged 20–30 years ago and were absent in uncut areas and stands less than 5 years old. Counts of red fox tracks were lowest in uncut stands and showed no consistent pattern among years of our survey with respect to stand age in second-growth forest. Hare tracks were most abundant in 20- and 30-year-old stands, and least abundant in stands less than 5 years old. Red squirrels were most common in uncut areas, but similar high values were also found in 20- and 30-year-old sites during 3 years when populations in the area were depressed. No selection of stands by age was seen for ermine. Numbers of tracks were significantly correlated with live captures of marten, hare, and red squirrels. Our results suggested that track abundance can be used as an index of habitat preferences and population trends. Highest counts were achieved in December for marten, red squirrel, and ermine, likely as a result of several types of over-winter mortality and inactivity in cold weather, which may have reduced counts in January and March. As a result of high and nonhomogeneous variance among transects and years, nonparametric statistical analysis was required. Transect length for fox and lynx should be substantially longer than 1 km (probably 3–5 km) to avoid numerous zero results.
Sexual differences in interyear survival and life-span of Richardson's ground squirrels
Authors: Michener Gail R.
Published: March 2009

Although equal numbers of males and females were weaned in a population of Richardson's ground squirrels studied in southern Alberta, interyear survival was lower for males than for females in each year of life. Consequently, the sex ratio was biased toward females in both the yearling and older adult cohorts (overall ≤ 23 males per 100 females), and maximum life-span of males was 4 years, whereas that of females was 6 years. Compared with several other species of Spermophilus, Richardson's ground squirrels have a larger litter size at birth and a shorter life-span.
Parelaphostrongylus andersoni (Nematoda: Protostrongylidae) in caribou (Rangifer tarandus) of northern and central Canada
Authors: Lankester Murray W. , Hauta P. Lynn
Published: March 2009

Woodland (Rangifer tarandus caribou) and barren ground (R. t. groenlandicum) caribou are reported for the first time as hosts of Parelaphostrongylus andersoni, greatly extending the known geographic range of this muscle nematode. Up to 56% of caribou in the Beverly herd, central Northwest Territories, passed dorsal-spined first-stage larvae in their feces. Animals less than 3 years old were more frequently infected and passed greater numbers of larvae than older animals. Larval output in winter and spring did not differ. Adults of the four elaphostrongyline nematodes known to occur in caribou are distinguished by their location in the host, the size of the worms, and the size and morphology of the male copulatory structures. There is an urgent need for tested and improved methods of differentiating larvae of P. andersoni and other elaphostrongyline nematodes from those of P. tenuis that cause neurologic disease in various North American cervids. Demonstration of the occurrence of P. andersoni in Rangifer sp. in North America raises the possibility that it originated in Eurasian cervids and may still occur in the Old World.
Annual, seasonal, and habitat-related variation in feeding habits of the arctic fox (Alopex lagopus) on St. Lawrence Island, Bering Sea
Authors: Fay Francis H. , Stephenson Robert O.
Published: March 2009

Small rodents, especially northern voles (Microtus oeconomus), were the most frequently occurring prey in the stomach contents and scats of arctic foxes collected on St. Lawrence Island between 1955 and 1970. Annual variations in the winter occurrence of voles in the stomach contents correlated well with variations in population density of the voles in the previous summer. However, when the foxes' summer dens were in or near large marine bird colonies, birds predominated in the diet. Even in winter, birds tended to occur more frequently in the diet of foxes trapped on bird cliffs than on the tundra. Since the birds are absent from the cliffs in winter, these evidently were from cached supplies. In terms of biomass, birds were of equal or greater importance than voles in the overall diet, and marine mammal carrion became most important in winter and early spring, when live prey were scarce. Although populations of live prey were abundant and readily accessible in summer, they were absent or inaccessible in winter; hence, even in this area of abundance, storage of food was essential for survival of foxes through the cold months.
Genetic variability among natural populations of the liver fluke Fascioloides magna in white-tailed deer, Odocoileus virginianus
Authors: Lydeard Charles , Mulvey Margaret , Aho John M. , Kennedy Phyllis K.
Published: March 2009

Liver flukes, Fascioloides magna, from white-tailed deer were collected from four locations in the southeastern United States for genetic analysis of spatial differentiation. Nine of 14 electrophoretic loci were polymorphic. Average individual parasite heterozygosity ranged from 4.6 ± 3.4 to 13.1 ± 5.9%. These levels of genetic variability are comparable to those reported for other species of parasites. Allele frequency differences among samples were noted for seven of the nine polymorphic loci. Rogers genetic distance values for interlocality comparisons increased with geographic distance between samples. Partitioning the total genetic variation in Fascioloides magna, 83% of the variance was found among individuals within sample locations, 4% between locations within Tennessee and South Carolina, and 13% between states.
Utilisation de l'habitat et organisation sociale du sanglier (Sus scrofa L.) à Doñana (Sud-Ouest de l'Espagne)
Authors: Braza Francisco , Alvarez Fernando
Published: March 2009

According to activity signs left on the ground (feces, footprints, and traces of rooting), wild boars on the Doñana Reserve preferentially occupy the marsh edge and the shrub area and, to a lesser extent, the marsh itself and the dryer zones of shifting or stabilized dunes. Habitat occupation follows a seasonal pattern, with the marsh edge being used progressively more from autumn to summer. The period of farrowing extends almost throughout the year, although virtually no births occur during the summer or in early autumn. Our data suggest two periods of sexual activity: an extended one during the summer, and a shorter one (although of greater influence on births) in late autumn. The basic social unit is the other group; several units may join to form larger family groups, which may comprise females with their young, rusty individuals, subadults, and sometimes male adults, although the latter tend to be solitary.
Missing opportunities to reproduce: an energy dependent or fecundity gaining strategy in white sucker (Catostomus commersoni)?
Authors: Trippel Edward A. , Harvey Harold H.
Published: March 2009

A definitive age or size at first maturity was lacking among both sexes of white sucker (Catostomus commersoni) in Gull-feather Lake. Highest incidence of maturity in females of a single age-class was 45%. Failure to mature in successive years occurred in 17% of females. Annual soma mass increment was significantly greater in population members exhibiting maturity relative to those which refrained from reproduction. Consequently, maintaining immaturity did not permit a large gain in future fecundity. Annual gain in fecundity potential by immature and nonreproducing adults ranged from 9.3 to 3.3%, substantially lower than that needed to compensate for the associated annual mortality of 30% in the age range 7–13 years. Gametogenesis in Gullfeather Lake females and males was characterized by abnormally low mature gonad weights relative to four comparative populations. Frequency of refraining from reproduction among five populations correlated positively with a spatial–temporal index of environmental hypoxia (r = 0.96) and correlated negatively with benthic densities of chironomid forage (r = −0.72). We accepted the hypothesis that onset of maturation was energy dependent.
Changes in peptide hormones and liver enzymes in the rainbow trout deprived of food for 6 weeks
Authors: Moon T. W. , Foster G. D. , Plisetskaya E. M.
Published: March 2009

The pancreatic peptide hormones insulin, glucagon, and glucagon-like peptide (GLP) modify metabolic flux in rainbow trout liver. This study quantifies the plasma titres of these peptide hormones using homologous radioimmunoassays after a 6-week fast and the coincident changes in specific enzymes in the liver. Fasting significantly changed a number of body parameters and depressed the plasma concentrations of each hormone, with the fall in insulin being the greatest and that in GLP the least. The relative hormone decline was such that the molar ratio of the glucagon-family peptides/insulin actually increased. Liver gluconeogenic enzymes were activated and pyruvate kinase underwent an apparent phosphorylation as indicated by altered kinetic parameters. These enzyme changes are evidence for an enhanced liver potential for gluconeogenesis during fasting. It is suggested that the changes in hormone molar ratios are responsible for the observed enzyme changes and are also key in the coordinated regulation of carbohydrate metabolism in the trout during fasting.
A feeding experiment with 6-methoxybenzoxazolinone and a wild population of the deer mouse (Peromyscus maniculatus)
Authors: Korn Horst
Published: March 2009

The responsiveness of a wild population of Peromyscus maniculatus to the secondary plant compound 6-methoxybenzoxazolinone was tested. No obvious response was found in terms of the start of the breeding season, which was earlier in females on the control grid. This effect could be explained by higher average body weights of the females in the control population. Peromyscus maniculatus living in the coastal forest of southern British Columbia can be considered opportunistic breeders. Other experiments with 6-methoxybenzoxazolinone are reviewed, and guidelines for future research are proposed.
Gastrointestinal helminths of woodland and barren ground caribou (Rangifer tarandus) in Canada, with keys to species
Authors: Fruetel Michael , Lankester Murray W.
Published: March 2009

A total of 21 species of parasitic helminths was recovered from wild and captive caribou. Gastrointestinal nematodes were represented by eight species of Ostertagiinae, four species of Nematodirinae, Trichostrongylus axei, T. vitrinus, Oesophagostomum venulosum, Trichuris ovis, Skrjabinema sp., and Capillaria sp. Other helminths included Dictyocaulus viviparus, Setaria yehi, and Moniezia sp. Nematodirus odocoilei, a common parasite of Odocoileus spp. is reported from caribou for the first time. Ostertagia leptospicularis is reported from North America for the first time. Illustrations and diagnostic keys are provided for the eggs, infective larvae, and adults of the gastrointestinal nematodes recovered from caribou.
Metazoan parasite infections in landlocked and anadromous Arctic charr (Salvelinus alpinus Linnaeus), and their use as indicators of movement to sea in young anadromous charr
Authors: Bouillon Daniel R. , Dempson J. Brian
Published: March 2009

Eighteen genera of metazoan parasites (Monogenea, 1; Digenea, 7; Cestoda, 4; Nematoda, 4; Acanthocephala, 1; Copepoda, 1) were collected from 172 landlocked and anadromous Arctic charr (Salvelinus alpinus Linnaeus) in northern Labrador. Four species (Lecithaster gibbosus, Diphyllobothrium dendriticum, Diphyllobothrium ditremum, and Salmincola carpionis) and one genus (Tetraonchus) have not previously been reported from Arctic charr in Labrador. The dominant parasites in the landlocked charr were Diplostomum sp., Crepidostomum farionis, and Diphyllobothrium ditremum. In the sea-run charr, Bothrimonus sturionis and Brachyphallus crenatus were dominant. Regression analyses indicated that the numbers of parasites were significantly correlated with host age (P < 0.001) for these species. All landlocked charr sampled were infected with parasites by age 1+ years whereas all sea-run charr were infected by age 3+. At 1+ years, 43% of the Arctic charr collected in the Ikarut River were infected with marine or brackish-water parasites, suggesting that some young charr, not yet ready for the annual seaward migration, may make short feeding excursions into salt water.
Selective stimulation of puffing activity in vitro with a juvenile hormone analogue by polytene chromosomes in the salivary glands of Chironomus thummi (Diptera)
Authors: Vafopoulou X. , Steel C. G. H. , Laufer H.
Published: March 2009

Salivary glands of Chironomus thummi prepupae were treated in vitro with various concentrations of the juvenile hormone analogue (JHA) methoprene and the puffing activities of Balbiani rings (BR) b and c were scored in cytological preparations of polytene chromosomes. In control cultures, both BRb and BRc regress rapidly. JHA treatment in vitro prevented regression at both these sites. In addition, BRb was found to expand within 60 min to a size two to three times larger than in control contralateral glands. The most effective concentration for stimulation of BRb and BRc in vitro was 10−7 M. In vivo treatment of prepupae with 10−7 M JHA also induced puffing activity in BRb and BRc to a degree similar to that observed following in vitro treatment. It is concluded that BRb, and perhaps also BRc, are juvenile hormone (JH) inducible chromosomal sites in Chironomus thummi salivary glands. This is the first report of chromosomal sites that are stimulated by JH in vitro in the absence of exogenous ecdysteroids. These findings support the view that JH may act at the gene level at separate loci from ecdysone.
Antidiuretic action of cyclic AMP, corpus cardiacum, and ventral ganglia on fluid absorption across locust ileum in vitro
Authors: Lechleitner R. A. , Audsley N. , Phillips J. E.
Published: March 2009

Locust ileal fluid transport (3.0–3.5 μL/h per ileum) and tissue volume were nearly constant after the 1st hour of incubation in physiological saline. Inhibition of absorption by KCN + iodoacetic acid and by azide indicated metabolic dependence of fluid transport. Fluid absorption occurred against osmotic concentration differences of up to 600 mosmol (luminal osmolarity > hemocoel osmolarity). Fluid absorption was stimulated by cyclic AMP, by both nervous and glandular lobes of the corpus cardiacum, and by the fifth ventral ganglion in a dose-dependent manner. All stimulants caused ilea to absorb against larger osmotic concentration differences. Stimulants in corpus cardiacum and fifth ventral ganglion extracts increased the osmotic permeability of the ileal wall at low osmotic concentration differences, whereas cyclic AMP had a much smaller effect on osmotic permeability. The absorbate remained hyperosmotic to the luminal saline under all conditions, and stimulants increased absorbate osmolarity.
A new species of the compound ascidian Eudistoma (Ascidiacea, Polycitoridae) from the northeastern Pacific
Authors: Lambert Gretchen
Published: March 2009

A new ascidian species, Eudistoma purpuropunctatum, is described from the San Juan Archipelago in Washington State. Recorded frequently for many years from fast-current subtidal areas, it was formerly considered a variant of Cystodytes lobatus (Ritter). Notes on color, texture, and habitat are included.
Morphologically distinct populations of the shorthead sculpin, Cottus confusus, and mottled sculpin, Cottus bairdi (Pisces, Cottidae), near the western border of Canada and the United States
Authors: Peden Alex E. , Hughes Grant W. , Roberts W. E.
Published: March 2009

Previously known within Canada from the Flathead River, nominal Cottus confusus also occur in the Kettle, Columbia, and Slocan rivers of British Columbia. The latter populations are similar to those from Washington, and possess a post-maxillary pore, lower numbers of pectoral rays, prickles behind the pectoral fin, and a smooth head. They are sympatric with nominal Cottus bairdi, with some individuals morphologically intermediate between the two species. Flathead River samples of nominal C. confusus differ from Columbia River populations in absence of the pore and prickles, higher fin ray counts, and larger head papillae. Specimens of nominal C. bairdi previously reported from the St. Mary River (Saskatchewan and Nelson drainages) and Milk River (Missouri River drainage) of Alberta are similar to Flathead River C. confusus, with others intermediate between Flathead River C. confusus and Columbia River populations of C. bairdi and C. confusus. Differences between Flathead River and Columbia River samples suggest that these populations require separate status in Canada. Similkameen River samples of C. bairdi are morphologically variable, individuals from upstream populations having some characters similar to those of C. confusus. A thorough study of C. bairdi and C. confusus in the United States is needed to redefine species limits.
A phylogenetic analysis of the Lumbriculidae (Annelida, Oligochaeta)
Authors: Brinkhurst R. O.
Published: March 2009

Though the Lumbriculidae is a monotypic taxon including Kurenkovia, there is no support from cladistic analyses for the Kurenkovidae. The unusual nature of the vasa deferentia, which run between the epithelial and muscular layers of the body wall as in some Haplotaxidae and Glossoscolecidae, may affect that decision. The Dorydrilidae is a sister-group to the Lumbriculidae. Lamprodrilus and the Lake Baikal endemic genera are now seen as advanced forms which may have given rise to some Asian and Pacific rim North American taxa. Several of the genera best represented in Europe have the plesiomorphic pattern of the reproductive system, with gonads in GI–GIII but atria limited to GII, so that two pairs of vasa deferentia are associated with them. This pattern is shared with the Branchiobdellida, and whereas median fusion of the atria has happened independently in the two taxa, these two taxa may arise from a common ancestor despite the degree of specialization to an epizooic habit in the branchiobdellidans. Most subgeneric taxa entered into the analyses are grouped at least close to their congeners, with the exception of Neoscolex, which may be more closely related to the pair of Kincaidiana species than to Styloscolex. Rhynchelmis may have an origin distinct from that of Lamprodrilus, Kincaidiana, and Neoscolex, as the loss of the anterior testes may be convergent and not monophyletic as suggested here.