bluuebunny/crossref_metadata_2025 huggingface dataset:
The effects of Salmincola californiensis (Copepoda: Lernaeopodidae) on the gills of farm-raised rainbow trout, Salmo gairdneri
Authors: Sutherland Daniel R. , Wittrock Darwin D.
Published: March 2009

Salmo gairdneri from an Iowa trout farm were found to be infested with Salmincola californiensis. Examination of gills from 235 trout revealed a prevalence of 83% and a mean intensity of 4.6 copepods. Preferred sites were established with the adult female attached usually on distal ends of the gill filaments or on gill bars and the chalimus attached to proximal regions of gill filaments. Examination of hematoxylin and eosin stained tissue sections of attached adult females revealed hyperplasia and hypertrophy ("tumor of attachment") and atrophy or growth inhibition ("crypting") of affected gill filaments. Eosinophilia and absence of mucous cells occurred in gill filaments affected by feeding activities and bulla attachment. Hyperplasia of the gill filament cartilaginous rod and resulting formation of a cartilaginous "bridge" between bulla and filament rod is described. Chalimus attachment elicited hyperplasia and frequently fusion of basal elements of adjacent gill filaments. Activities of adult females attached to gill bars resulted in proliferation of stratified squamous epithelium, infiltration of granular leucocytes and reduction of mucous cells. Damage to gill tissues of trout maintained in dense populations offish culture is deemed significant, especially during summer periods of low dissolved oxygen.
Cobbionema capense n.sp. from Swartkops estuary, Port Elizabeth (Nematoda: Selachinematidae)
Authors: Furstenberg J. P. , Heyns J.
Published: March 2009

Cobbionema capense n.sp. from Swartkops estuary near Port Elizabeth is described. The new species is distinguished by the moderately cuticularized buccal cavity wall and teeth ridges.
The significance of sexual dimorphism in the mating system of two species of tephritid flies (Aciurina trixa and Valentibulla dodsoni) (Diptera: Tephritidae)
Authors: Dodson Gary
Published: March 2009

The mating systems of Aciurina trixa and Valentibulla dodsoni (Diptera: Tephritidae) were observed in natural populations and field cage studies. Measurements of field-collected individuals of both species revealed that females were larger than males based on five size categories, but males had larger forefemora. Male behavior suggested that selection might favor increased foreleg size, due to a resulting enhancement of male ability to seize females prior to mounting. Male forefemur size was found to be a predictor of copulatory success in both species. Hypotheses concerning the adaptive significance of this sexual dimorphism are discussed.
Do some female spruce grouse not breed?
Authors: Keppie Daniel M.
Published: March 2009

The evidence pertaining to whether all female spruce grouse (Dendragapus canadensis) breed is evaluated. By using the criteria of being found with a nest, with a brood, or with a brood patch, 86% of females were known to breed (71% in Alberta; 95% in New Brunswick; 94% in Ontario); there was no evidence of an age-class difference. There is, as yet, no direct evidence that some female spruce grouse do not breed.
Can alkaloids and tannins in plants influence food choice of meadow voles (Microtus pennsylvanicus)?
Authors: Bélanger Jacques , Bergeron Jean-Marie
Published: March 2009

The aim of the present study was to relate food choice of meadow voles (Microtus pennsylvanicus) living in a variety of habitats to the presence or absence of two families of chemical compounds (alkaloids, tannins) that are widespread in plants. Voles seemed to prefer resources that possessed one or both of the compounds and to reject others even if they had no alkaloids or tannins. Several abundant species were not used by voles whether or not they possessed alkaloids or tannins. Our results show no pattern of association between the presence or absence of alkaloids and tannins and vole food preferences.
Redescription of Dunhevedia serrata Daday, 1898 (Cladocera, Chydoridae) and a description of Dunhevedia americana sp.nov. from America
Authors: Rajapaksa R. , Fernando C. H.
Published: March 2009

Dunhevedia serrata, considered a pantropical species, was found to consist of two species. The new species, restricted to the Americas, is designated Dunhevedia americana sp.nov. Dunhevedia serrata is redescribed, and a key is provided for all the known species of the genus. Dunhevedia serrata is not found in America but occurs in all other zoogeographic regions with tropical areas.
Labrocibarial sensilla in the female sand fly Lutzomyia longipalpis Lutz &Neiva (Diptera: Psychodidae)
Authors: Jefferies D.
Published: March 2009

Five types of sensilla have been identified on the distal tip of the fascicle and within the food canal in the female of Lutzomyia longipalpis Lutz &Neiva, four on the labrum and one in the cibarium. The external morphology of these sensilla is described for the first time, using scanning electron microscopy, allowing a more direct comparison with the mouthpart sense organs present in other groups of haematophagous Diptera. No evidence for the presence of cibarial chemoreceptors was found although such sensilla have been reported in all other groups of Diptera examined.
Parasitology: today and tomorrow
Authors: Mettrick D. F.
Published: March 2009

Parasites have, over the centuries, been responsible for high mortalities among humans and domestic and wild animals. The presence of parasitic infections has made vast areas of the world uninhabitable for both humans and animals. Major strengths of Canadian parasitology include wildlife parasitology, systematics, and taxonomy. Experimental studies in parasitology are limited; in particular the subdisciplines of parasite molecular and cellular biology, biochemistry, immunology, and neurobiology are very limited. There is concern that we will not be able to maintain the quality of Canadian research in parasitology, particularly in the emerging new technologies. It is greatly to the credit of those early Canadian parasitologists, who laid the foundations for today's advances in parasitology, that a relatively small group of approximately 100 professional parasitologists has today reached a very high standard of parasitological research. The next 25 years will be an exciting period as new insights allow us to further understand the complexity of host–parasite relationships. The development of new vaccines, drugs, and vector control point to significant reductions in parasitic infections.
Asymmetric contests among sawyer beetles (Cerambycidae: Monochamus notatus and Monochamus scutellatus)
Authors: Hughes Austin L. , Hughes Marianne K.
Published: March 2009

Females of both Monochamus scutellatus (Say) and Monochamus notatus Drury (Coleoptera: Cerambycidae) preferred to oviposit in large diameter pine logs. When females of both species were present, oviposition on the largest diameter log by M. scutellatus was much reduced. There were both inter- and intra-specific contests among females, usually over oviposition holes cut by females in the bark. Contests among females occurred disproportionately on the largest logs. Previously inseminated females paired with radiation-sterilized males laid no fertile eggs, supporting the hypothesis that a male is highly likely to fertilize eggs laid by a female with which he is paired. In intraspecific contests among females over oviposition holes and among males over females, a challenger could supplant a resource holder only in an escalated contest. However, in interspecific contests, M. notatus challengers were able to supplant M. scutellatus resource holders without escalation. In both sexes, a contest was more likely to be nonescalated when the resource holder was larger than the challenger. Among males, a larger resource holder was significantly more likely to repel a smaller challenger than was a larger challenger to replace a smaller resource holder.
Extraction and characterization of the blue-sensitive visual pigment of the toad Bufo marinus
Authors: Sillman A. J.
Published: March 2009

The blue-sensitive visual pigment of the green rods of Bufo marinus was extracted with digitonin. The pigment is present in an amount equal to about 11% that of rhodopsin. It is based on vitamin A1 and exhibits a maximum absorbance of 433 nm. The pigment is labile and readily destroyed by hydroxylamine, regenerates to a much greater degree than does rhodopsin, and is more effectively extracted from the membrane than is rhodopsin. The green rod pigment of Bufo marinus appears to share the same physical and chemical properties as the green rod pigments of other amphibians. Therefore, the results of electrophysiological studies on the green rods of Bufo marinus can be more confidently generalized to other species. The results are discussed in terms of the blue phototaxis that is characteristic of many amphibians.
Experimental evidence of the fundamental feeding niche in Cenocorixa (Hemiptera: Corixidae)
Authors: Reynolds J. D. , Scudder G. G. E.
Published: March 2009

The fundamental feeding niche of Cenocorixa bifida hungerfordi Lansbury and Cenocorixa expleta (Uhler) from saline lakes (500–20 000 μS cm−1 at 25 °C) was determined in laboratory experiments. Each species was offered a variety of potential foods, to determine potential dietary overlap. No significant differences in food acceptance were seen between corixids collected from different lakes or at different seasons. The species were both carnivorous and predaceous, showing little propensity to feed on plant material. Adults of both species attacked and fed on chironomid larvae most frequently; larval instars were less specific. Cenocorixa expleta adults and larval instars of both C. expleta and C. bifida fed more on dead than living food organisms. When offered mixed live Zooplankton, C. bifida chose more Ceriodaphnia than Diaptomus, whereas C. expleta showed no such selection; these differences were not seen with dead Zooplankton. Cenocorixa bifida and C. expleta coexist at moderate salinities, and appear physiologically capable of inhabiting the entire salinity range encountered. Their fundamental feeding niches, although not identical, overlap considerably and could result in competition for food. This could lead to the exclusion of C. expleta from low salinity lakes.
Ontogeny of the separation call in Northern Bobwhite (Colinus virginianus)
Authors: Baker James A. , Bailey Edward D.
Published: March 2009

Selected frequency and duration characteristics were measured on sonograph tracings of lost and separation calls of two inbred familial lines of Northern Bobwhite (Colinus virginianus) chicks at 1 day, 1 week, then weekly to 12 weeks, and again at 1 year to determine the mode and rate of development of the separation call. Chicks separated from covey mates responded with a series of one-note calls until 4 weeks of age when the single note calls increased in duration and separated into the two-note call. A gradual increase in frequency modulation and duration of both notes continued until the adult form of the call was complete at 12 weeks. Starting frequency of the lost and separation calls differed significantly between familial lines from 1 day through 12 weeks. No other characteristics showed such consistent differences though differences did occur at some ages. However, though frequency characteristics might function for individual identification, potential for individual variation and modification is greater in duration characteristics.
Diseases as components of mammalian ecosystems: mayhem and subtlety
Authors: Yuill Thomas M.
Published: March 2009

Parasitic and infectious agents are found in all mammals in every ecosystem. Death of the mammalian host is unusual, and only occurs (i) if serious illness facilitates transmission, as in rabies, (ii) if the parasite does not depend on the affected host species for survival and can complete its life cycle after the host dies, or (iii) if the pathogen moves through host populations over wide geographic areas, over a long period of time. The high mortality rate occasioned by myxomatosis in Australia and Europe is an example of a pathogen occurring in a completely susceptible population for the first time. Coevolution of virus and host has resulted in a decrease in mortality. Some other diseases affect host populations by causing adverse effects on natality or by interfering with normal movement. Brucellosis in caribou has both effects. The effects of most diseases in populations of wild mammals are more subtle. Infectious and parasitic agents can have adverse effects on the host energy balance by reducing energy intake or increasing energy costs through higher body temperatures and metabolic rates. Diseases of mammals have certain practical considerations as well. Attempts to manage populations of wild mammals may inadvertently create situations where disease transmission is facilitated, as was the case with anthrax in Africa. Wild mammals harbor diseases that are transmissible to man and movement of these wild mammals in commerce can spread the disease, as has been the case with Hantaan virus. Also, ecological changes can favor increases in abundance of some animals that are reservoirs of human disease, as has been the case with Bolivian hemorrhagic fever and Lassa fever in Africa. Wild mammals and domestic mammals frequently share common diseases and these diseases may pose economic threats which can lead to campaigns to reduce numbers of wildlife reservoirs. Some of the challenges and opportunities associated with rapid ecologic changes are discussed.
Characterization of phenoloxidases from larval cuticle of Sarcophaga bullata and a comparison with cuticular enzymes from other species
Authors: Barrett F. Michael
Published: March 2009

A tyrosinase, enzyme A, and a laccase, enzyme B, have been partially purified from larval cuticle of the flesh fly Sarcophaga bullata. Enzyme A (EC 1.10.3.1, o-diphenol: O2 oxidoreductase) oxidizes o-diphenols but not p-diphenols, is strongly inhibited by phenylthiourea, and has a pH optimum around pH 6.5–7.0. Assays on intact cuticle suggest that it becomes maximally activated at pH between 8 and 9. Enzyme B (EC 1.10.3.2, p-diphenol: O2 oxidoreductase) oxidizes both o-diphenols and p-diphenols, is not inhibited by phenylthiourea but is inhibited by concentrations of sodium azide that have little effect on enzyme A, and has a pH optimum near pH 4.5. Enzyme A was identified in extracts of cuticle from nine other species representing five orders. Enzyme B was much less readily extractable but was partially purified from larval cuticle of Phormia regina, Musca domestica, and Lucilia sericata. A summary of all species studied to date makes possible the test of a hypothesis about the distribution of these cuticular phenoloxidases within the Insecta.
X-ray microanalysis of the cuticle surface of the terrestrial isopod Porcellionides pruinosus
Authors: Hadley Neil F. , Hendricks Gregory M.
Published: March 2009

The elemental composition of the cuticle surface and associated microstructures of the isopod Porcellionides pruinosus was examined using energy dispersive X-ray spectroscopy (EDS). The cuticle surface (epicuticle + exocuticle), balls, tricorns, tricorn lips, and epimeral sensilla all contained abundant calcium, with smaller amounts of sulfur, potassium, phosphorus, and chloride also present. Silicon was detected only in the sensilla. The ratios of these lesser elements to calcium were similar in the tricorns, balls, and lips, supporting their common origin. There was a marked reduction in the amount of calcium in the exuviae, and in the amount of calcium and other elements in newly released young when compared with intermoult adult cuticle. Cuticle treated with acetic acid exhibited loss of structural support and no calcium peak in the EDS spectrum, whereas treatment with EDTA had no effect on calcium levels or cuticle morphology.
The influence of temperature on the depth distribution of sympatric Erpobdellidae (Hirudinoidea)
Authors: Gates T. E. , Davies Ronald W.
Published: March 2009

Inter- and intra-specific differences in the behavioral responses of two sympatric Erpobdellidae, Nephelopsis obscura and Erpobdella punctata, to overall water temperature change and thermal gradients were investigated in the laboratory. The results are compared with the seasonal migratory patterns recorded in lentic field habitats. While temperature preference does act as a directional factor in the spring movements to shallow water, only starved small N. obscura and starved large nonreproductive E. punctata showed a preference for colder temperatures after acclimation to a summer temperature of 20 °C. Thus, other components of the population do not use temperature as a cue for their movements to deeper waters in the autumn. It is suggested that the seasonal differential depth distributions shown by components of both species result in a spatial separation of potential competing size groups complementing the inter- and intra-specific size class differences in food resource utilization and temporal differences in resource allocation already demonstrated.
Temperature-dependent sex determination in reptiles: validity of sex diagnosis in hatchling lizards
Authors: Bull J. J.
Published: March 2009

In many reptiles, sex is determined by the incubation temperature of the egg. Studies of this phenomenon have usually diagnosed sex from gonads of hatchlings. The present study establishes the validity of this procedure in a lizard with temperature-dependent sex determination by diagnosing gonadal sex in hatchling leopard geckoes (Eublepharis macularius) and comparing these diagnoses with the sexes of the same animals as adults or subadults. The diagnosis of sex soon after hatching agreed with the subsequent diagnosis in all of the 96 animals studied. In a separate experiment, 29 eggs were divided between a male-producing and a female-producing treatment. Adult–subadult sex was significantly associated with temperature, indicating that temperature determined sex, and excluding for the first time the joint possibilities of differential mortality and (or) sex reversal after hatching. Previous fundamental assumptions about the nature of temperature-dependent sex determination in reptiles are consequently well established.
The Simuliidae (Diptera) of Sri Lanka. Descriptions of species in the subgenera Eusimulium and Gomphostilbia of the genus Simulium
Authors: Davies D. M. , Györkös H.
Published: March 2009

This paper on the Simuliidae of Sri Lanka provides notes on Simulium (Eusimulium) aureohirtum and describes three new species of Simulium (Gomphostilbia): Simulium krombeini, Simulium ela, and Simulium dola. The females of S. (G.) pattoni and Simulium (Gomphostilbia) ceylonicum comb.n. are redescribed and the males, pupae, and larvae are described for the first time. Keys are provided for separating the subgenera of Simulium and the species of Gomphostilbia in Sri Lanka. Some taxonomic comparisons are made with related Oriental species and a few biological notes are given.
Age determination of adult field crickets: methodology and field applications
Authors: Zuk Marlene
Published: March 2009

Details of a method originated by A.C. Neville for aging adult insects by counting daily growth rings in tibial or other body sections are given. A test of the method's accuracy using laboratory-reared field crickets (Gryllus pennsylvanicus and Gryllus veletis) showed that the number of growth rings counted is equivalent to the number of days past adult molt until the insect is approximately 25–30 days old, when cuticle growth is completed and rings are no longer added. Field populations of the two cricket species sampled in 2 years seldom contained individuals with more than 18 rings. Several applications for the technique to ecological and behavioral studies are given, using examples from data on G. veletis and G. pennsylvanicus.
Redescription of Skrjabinocerca prima Shikhobalova, 1930 (Nematoda: Acuarioidea) from the American Avocet (Recurvirostra americana Gmelin)
Authors: Wong P. L. , Bush A. O. , Anderson R. C.
Published: March 2009

Skrjabinocerca prima Shikhobalova, 1930 is redescribed from material collected from the American Avocet (Recurvirostra americana Gmelin) collected in Alberta, Canada (prevalence 88%). The parasite was not present in avocets collected from Manitoba.
Chloride-dependent electrogenesis by the anterior intestine of Achatina fulica
Authors: Enyikwola O.
Published: March 2009

The serosal side of the anterior intestine of the giant African snail, Achatina fulica, is a few millivolts negative to the mucosal side in vivo and in vitro. The potential difference ranged from 1.0 to 7.5 mV (average 2.8 ± 1.4 mV) and the short-circuit current difference, from 28.0 to 150.0 μA/cm2 (average 75.0 ± 12.8 μA/cm2). Good stirring is essential for the maintenance of the electrical gradient in vitro. The electrical potential does not depend on K+, Mg2+, Ca2+, or Na+ but requires Cl− on the mucosal side. The electrical gradient is reduced by cyanide, 2,4-dinitrophenol, and anoxia but not by ouabain, furosemide, or bumetanide. The transmural potential difference and short-circuit current were predominantly dependent upon aerobic metabolism. However, a finite residual component was dependent upon glycolytic energy. It is concluded that the role of chloride transport across the intestinal epithelium may be to facilitate fluid absorption from the lumen into the haemolymph.
Salsuginus bermudae sp.n. (Monogenea: Ancyrocephalidae) from Fundulus bermudae Gunther and Gambusia affinis (Baird and Girard) in Bermuda
Authors: Rand Thomas G. , Wiles Michael
Published: March 2009

Salsuginus bermudae sp.n. is described from gills of mangrove minnow, Fundulus bermudae Gunther, and mosquito fish, Gambusia affinis (Baird and Girard), from Bermuda. It differs from S. angularis by its shorter ventral hamuli (20–23 versus 22–26 μm); from S. fundulus, S. spirae, and S. heterocliti by its shorter dorsal and ventral hamuli (17–21 versus 22–26, 22–26, 20–24 μm, respectively, for dorsal hamuli and 20–23 versus 23–29, 23–27, 25–28 μm, respectively, for ventral hamuli); from S. bahamianus by its longer ventral hamulus superficial root (6–10 versus 5–6 μm); and from S. umbraensis by its shorter dorsal hamuli and dorsal bar (17–21 versus 23–24 and 19–26 versus 30–31 μm, respectively). It is indistinguishable morphometrically from S. seculus, yet differentiable from other species of Salsuginus by its dorsal and ventral hamuli and by its accessory piece. Mangrove minnows may be distributed in separate populations in the various Bermudian lakes. Differences in accessory piece morphology allowed discrimination of two morphotypes isolated in separate small mangrove minnow populations from two lakes (Mangrove and Lover's) which have different physicochemical characteristics. A possible isolating mechanism is discussed.
The effects of two postemergence herbicides on hatchability of chicken eggs
Authors: Wayland Mark , Batt Bruce D. J. , Cowan Wayne F.
Published: March 2009

Hatchability of chicken eggs treated at four different embryo ages was not affected by immersion in sethoxydim herbicide or a 2:1 combination of fenthiaprop ethyl and fenoxaprop ethyl at three different concentrations. These data may be useful in evaluating the potential hazard of these chemicals to upland nesting game birds.
Changes in gut dimensions and capacity of Peromyscus maniculatus relative to diet quality and energy needs
Authors: Green David A. , Millar John S.
Published: March 2009

Deer mice were maintained on diets diluted with 25, 30, and 45% fibre at 20 °C and on diets of standard laboratory chow at 20, 15, 10, and 5 °C to determine the effects of decreased diet quality and increased energy requirements on the dimensions of the alimentary tract. Weight of the small intestine with contents and of the caecum with contents showed the greatest responses to decreasing diet quality. These increased 59 and 61%, respectively, when diet contained 45% cellulose. Weight of the small intestine with contents showed the greatest response to increasing energy requirements by increasing 96% when temperatures were reduced to 5 °C. However, all weight and length measurements increased with both increased energy demands and decreased diet quality. Weight of the intestinal tract with contents provides an indicator of daily food intake, but the gross dimensions of the alimentary tract cannot be used to differentiate between energy requirements and diet quality.
Sex and seasonal differences in metabolism in the red-sided garter snake, Thamnophis sirtalis parietalis
Authors: Crews David , Grassman Mark , Garstka William R. , Halpert Andrew , Camazine Brian
Published: March 2009

Field and laboratory studies revealed that male and female Canadian red-sided garter snakes, Thamnophis sirtalis parietalis, differ in the pattern of body mass gain, nutrient storage, and nutrient availability following emergence from hibernation. In nature males fail to gain weight or store fat until 3 weeks after emergence from prolonged (7 months) winter hibernation. In the laboratory males also do not exhibit an increase in body mass following emergence from artificial hibernation (17 weeks) until mating behavior has ended, about 3 weeks after emergence; as in free-living males, fat stores do not increase until all mating behavior has ceased. In contrast, females in both field and laboratory populations gain weight steadily following emergence but exhibit a gradual decrease in the proportion of abdominal fat reserves to body mass. While females exhibit increased serum levels of protein, unchanged levels of glucose, and decreased levels of lipid, males exhibit unchanged levels of protein, increased levels of glucose, and decreased levels of lipid. Males display a greater resting oxygen consumption postemergence compared with females. Oxygen consumption was decreased in both sexes during the period coinciding with mating; at the end of breeding, oxygen consumption increased. These data are consistent with the marked differences in reproductive behaviors between the sexes following emergence from hibernation.
Age-related variation in the nutrient reserves of breeding American Coots (Fulica americana)
Authors: Alisauskas Ray T. , Ankney C. Davison
Published: March 2009

We analyzed the relationship between age and nutrient reserves of 186 American Coots, Fulica americana, collected in southern Manitoba during the breeding season in 1981. The first principal component from the correlation matrix of 13 morphological variables was used as the measure of body size. Protein reserves, as indexed by lean dry weight, and fat reserves were related to body size, but the relationship for fat reserves was weak. The oldest coots of each sex were the largest, and this partly explained their larger protein reserves compared with the youngest coots. However, by scaling different sex–age groups to the same body size, we found that older coots had relatively larger protein reserves before breeding than did younger coots. Males and females did not differ in relative protein reserves, but females had relatively more fat reserves than did males. The results also indicated that body size is an important consideration in studies of nutrient reserve dynamics.
Development of Macrocentrus grandii Goidanich within microsporidian-infected Ostrinia nubilalis (Hübner) host larvae
Authors: Cossentine J. E. , Lewis L. C.
Published: March 2009

The impact of each of three microsporidia on the braconid parasitoid Macrocentrus grandii Goidanich within infected European corn borer, Ostrinia nubilalis (Hübner), hosts was studied. Nosema pyrausta (Paillot) and Nosema sp. infected M. grandii larval tissue. All three microsporidia decreased adult parasitoid eclosion. Female M. grandii eclosing after development in hosts infected with Vairimorpha necatrix (Kramer) or N. pyrausta lived for 10 to 14 days. Females infected with these two species did not transmit the pathogens transovarially to their offspring. Only male M. grandii adults eclosed from hosts infected with Nosema sp.
Millipeds (Diplopoda) of the Galapagos Islands, Ecuador
Authors: Shear William A. , Peck Stewart B.
Published: March 2009

Six species of millipeds are reported for the first time from the Galapagos Islands, raising the known diplopod fauna to eight species. Agenodesmus nullus n.sp. is described (Furhmannodesmidae). Six members of the fauna are in the eyeless order Polydesmida, and one species each are in the orders Polyxenida and Polyzoniida. Most species were probably introduced by man. Only Nesodesmus insulanus Chamberlin may be naturally occurring and endemic.
Distribution and movements of Black Guillemots (Cepphus grylle) in coastal waters of the southwestern Bay of Fundy, Canada
Authors: Nol E. , Gaskin D. E.
Published: March 2009

Distribution and movement patterns are described for summering (nonbreeding) Black Guillemots in the Deer Island region of the southwestern Bay of Fundy, Canada. Guillemots were distributed in areas with moderate current velocities (range, 30–68 cm/s) and shallow to intermediate depths (range, 17–31 m). The birds appeared to avoid shallow and deep areas with fast- or slow-moving water. Guillemots preferred islands with extensive underwater ledges, presumably because these harboured sufficient prey and provided protection from fast-moving tidal waters. Guillemots moved in and out of the approaches passively with the tide and, in contrast to larids in the region, made only small-scale flights to reposition themselves in relation to food resources.
Chandlerella bushi n.sp. and Splendidofilaria caperata Hibler, 1964 (Nematoda: Filarioidea) from Fulica americana (Gruiformes: Rallidae) in Manitoba, Canada
Authors: Bartlett Cheryl M. , Anderson R. C.
Published: March 2009

Chandlerella bushi n.sp., from a lymphatic vessel in the leg of one of seven adult American coots (Fulica americana) collected at Delta Marsh, Manitoba, is distinguished by the twisted distal end of the left spicule and by the length of the right spicule being about twice that of the left. Microfilariae of C. bushi occurred in the blood. Adult male and female Splendidofilaria caperata were also found in the coot infected with C. bushi, although microfilariae were not present in the reproductive tracts of females or in the host's blood. Microfilariae were not found in the blood of 27 adult coots collected near Brooks, Alberta, Canada. Apparently, no species of Splendidofilaria or Chandlerella have previously been identified from Gruiformes.
Reproduction and recruitment of individually identified humpback whales, Megaptera novaeangliae, observed in Massachusetts Bay, 1979–1985
Authors: Clapham Phillip J. , Mayo Charles A.
Published: March 2009

Humpback whale mother–calf pairs from a currently unexploited population were observed in Massachusetts Bay between 1979 and 1985. During this period, 44 individually identified mature females were observed, with a total of 72 calves. Of the 20 mothers observed with more than one calf during the study period, 12 had two calves and 8 had three calves. The observed calving intervals were 1 year (n = 1), 2 years (n = 16), 3 years (n = 10), and 4 years (n = 1). The crude birth rate varied from a low of 0.045 in 1981 to a high of 0.103 in 1983 (mean = 0.075). An alternative calculation of reproductive rate yielded a range of 0.30–0.43 calves per mature female per year. Mature females were observed significantly more frequently in years when they had a calf than in years when they did not. Females with calves associate with other whales less frequently than females without calves. Observations of calves feeding suggest that weaning may begin when calves are 5–6 months of age. Forty-five of the 49 calves born before 1985 separated from their mothers during the calf's second winter, while 37 of the 49 were observed to return to the study area in 1 or more years after separation from their mothers. One calf is known to have died. Two females born during the study period returned with calves of their own in later years. The high return rate of calves in years after separation strongly suggests that the composition of a humpback whale feeding stock is determined matrilineally.
Ecological analysis of the helminths of round-tailed muskrats (Neofiber alleni True) in southern Florida
Authors: Forrester Donald J. , Pence Danny B. , Bush Albert O. , Lee David M. , Holler Nicholas R.
Published: March 2009

The helminths of 114 round-tailed muskrats (Neofiber alleni True) from sugarcane fields in southern Florida were studied. Eight species of helminths were found, one cestode and seven nematodes. Of the 114 muskrats studied, 113 were infected with one to five species (mean = 2.6). Intensities varied from 1 to 2543 (mean = 149.3). Strongyloides sigmodontis was more abundant in juveniles and males and during the wet season. Carolinensis kinsellai was more abundant in juveniles while Raillietina sigmodontis was found only in males. Trichostrongylus spp. were more abundant during the wet season and in juveniles. None of these variables was interactive. The helminth community of round-tailed muskrats was dominated by satellite species, most of which were apparently derived from cotton rats (Sigmodon hispidus).
Effects of early feeding experience and age on the cannibalistic propensity of the land snail Arianta arbustorum
Authors: Baur Bruno
Published: March 2009

The influence of early feeding experience on egg cannibalism was examined in hatchlings of the land snail Arianta arbustorum. The propensity for cannibalism was not affected by cannibalistic or by vegetarian early feeding experience. It was, however, negatively correlated with the age of the snails. Freshly hatched snails with no prior feeding experience chose eggs exclusively, while 16-day-old snails preferred vegetable food. Furthermore, the cannibalistic propensity varied between offspring from different clutches. Restriction of the cannibalistic propensity to the hatchling stage, its nonmodifiability, and differences in its extent between clutches suggest that egg cannibalism in A. arbustorum is a genetically determined trait.
Visualizing metabolic transitions in aquatic mammals: does apnea plus swimming equal "diving"?
Authors: Castellini Michael A.
Published: March 2009

While diving, aquatic mammals must balance the oxygen conservation requirements of apnea with the oxygen utilization requirements of exercise. The resulting metabolic state depends on a complex range of behavioral, physiological, and metabolic conditions as required by the particular dive profile. Thus, at the one extreme of long duration diving, oxygen conservation requirements will outweigh those of exercise, while under conditions of rapid, short diving or propoising, exercise parameters will probably be of more importance than those of oxygen conservation. In the last several years, techniques for monitoring radioactively tagged plasma metabolites have allowed the visualization of metabolic variation throughout various diving and surface exercise regimes in aquatic mammals. By comparing such tracer turnover dilution curves under conditions of surface exercise, quiet forced diving, free diving, and sleep apnea, patterns emerge that demonstrate the extreme metabolic plasticity of the diving response. These comparisons have led to the conclusions that even short diving periods probably involve a marked change in metabolic steady state, and that aerobic diving is not simply analogous to aerobic exercise.
pH and hypometabolism in mammalian hibernation
Authors: Malan A.
Published: March 2009

In mammalian hibernation, the reduction of metabolic rate occurs by three processes: inhibition of cold-induced thermogenesis, temperature effect on metabolic reaction rates (Q10), and a further inhibition. Concomitantly, the animal undergoes a marked respiratory acidosis (CO2 retention). At the intracellular level, a respiratory acidosis occurs in brain and muscles, suggesting that intracellular pH regulation is depressed. The hyperventilation of early arousal provides evidence for the hypothesis that acidosis exerts an inhibition in hibernation, and should be removed to permit thermogenesis. Muscle glycolysis and brown adipose tissue thermogenesis are depressed by acidosis in vitro, but a decrease in pH probably also affects other systems, especially the preoptic area of the hypothalamus.
Anaerobic contributions to metabolism in diving seals
Authors: Elsner Robert
Published: March 2009

This presentation contains a compilation and discussion of the evidence for the capacities of various phocid seal organs to resist the unfavorable effects of severe hypoxia by conversion to anaerobic metabolism. Tissues for which experimental evidence has been obtained include skeletal muscle, kidney, heart, and brain. The argument is made that these capacities represent a reserve for tolerance of the asphyxia of long dives.
Physiology and biochemistry of long-term fasting in birds
Authors: Cherel Yves , Robin Jean-Patrice , Maho Yvon Le
Published: March 2009

Various bird species regularly fast in connection with breeding, migration, or drastic climatic conditions. The metabolic response of penguins and domestic geese to fasting has been studied in detail. These large birds, in contrast to small species, do not become torpid when they are fasting. Nevertheless, they reduce their rate of energy expenditure by decreasing both resting metabolic rate and locomotor activity. From changes in the loss of body mass, the fast of penguins and geese has been divided into three phases: I, the loss of body mass decreases; II, it remains at a minimum level; and III, it increases. These phases reflect metabolic adjustments. Phase I is a rapid phase of adaptation, marked by a decrease in protein catabolism and mobilization of lipids. Phase II is a phase of economy, during which more than 90% of the energy expenditure derives from lipids, while protein catabolism remains at a minimum level. In phase III there still are lipid reserves and this phase is reversible; it is, however, critical because proteins are no longer spared. Data in the literature suggest that these three phases may also be used to describe how a wide variety of wild and domestic birds adapt to fasting.
Courtship and spawning competition in pink salmon (Oncorhynchus gorbuscha)
Authors: Keenleyside Miles H. A. , Dupuis Hélène M. C.
Published: March 2009

Male pink salmon cluster in groups of up to 10 or more around a female as she prepares the substrate for spawning. The largest male in the group (in length and dorsal hump development) stays closest to the female; the others maintain a size-related hierarchy behind the pair. Position in the group is determined by frequent aggressive interactions among the members. Often a relatively small "outlier" male holds position near the central pair, to one side of the nest. These males are "female-like" in colour and size, and the dorsal hump is small. When the primary male settles into the nest bottom and quivers beside the female, males in the associated group, including the small outlier, dash into the nest. When the female and primary male spawn, some or all of the group males release sperm. Nest-digging females are territorial; they attack other females and small males. Their primary males are aggressive towards other males, but not towards females. They frequently attack the males closest to them in their group, but also attack nongroup males, including other large males who try, usually unsuccessfully, to replace them as the primary male. The phenomena of many males at a single nest, great variability in dorsal hump development, and outlier vs. fighting behaviour are all associated with male competition for access to spawning females.
Use of ground and arboreal microhabitats by Peromyscus leucopus and Peromyscus maniculatus
Authors: Graves Sherri , Maldonado Jesús , Wolff Jerry O.
Published: March 2009

The fluorescent powder tracking technique was used to measure the distance traveled on the ground, on logs, and in trees by Peromyscus leucopus and Peromyscus maniculatus to determine if differential use of ground and arboreal microhabitats was sufficient to reduce niche overlap. Peromyscus maniculatus was more active in large trees than P. leucopus, but the two species traveled comparable distances on the ground, on logs, and in small trees. Vertical microhabitat segregation between these species was minimal and not significant enough to reduce niche overlap.
The behavior of moose at natural mineral springs in Quebec
Authors: Couturier Serge , Barrette Cyrille
Published: March 2009

The Matane Wildlife Reserve (48°40′ N, 66°55′ W) is the only location in Quebec known to have mineral springs. Their water is rich in sodium (172.5 ± 97.1 ppm, n = 17 vs. 3.6 ± 2.6 ppm, n = 10, in streams flowing nearby) and other minerals. We observed moose (Alces alces) there for a total of 11 months over three summers. Maximal use of the springs occurred in early July. Moose visited springs mostly around sunrise and sunset, spending a mean (± SD) of 24.3 ± 26 min (n = 691) at the springs, 20.7% ± 17% of which was spent drinking, almost always right at the actual spring (about 0.1 m2). Calves started visiting springs in late June, always with their mothers, but rarely drank before September. Moose interacted aggressively, particularly to displace one another from the small springs. Lactating females chased all other moose away when they were accompanied by their calves. Such females spent much less time drinking when their calves were present than when they visited a spring alone. Moose usually urinated at a spring, but almost never on the actual spring itself, and most often close to the end of a visit. Of 360 urinations, 32.2% were hock urinations. Mineral springs seem to be important, although incidental, social gathering places, where the hunger for salt forces moose to have a more intense social life than their otherwise solitary habits allow.
Artificial fertilization, rearing, and timing of stages of embryonic development of the anadromous sea lamprey, Petromyzon marinus L.
Authors: Langille Robert M. , Hall Brian K.
Published: March 2009

For experimental analysis of agnathan (lampreys and hagfishes) development, the only choice at present is the lamprey, yet these animals present severe restrictions to their use. The average duration of the breeding period of mature anadromous sea lamprey, Petromyzon marinus, caught off the coast of Nova Scotia, is approximately 3 weeks, after which the animals die. At present no hormonal treatment or other method exists either to initiate precocious sexual development or to effectively increase the natural, limited fertilization period of this species. The present study demonstrates that by (i) anaesthetizing lampreys in a buffered medium and housing animals in darkness or reduced light to reduce stress, (ii) raising embryos from each fertilization at three different temperatures, 15, 18, and 21 °C, and (iii) staggering fertilizations, the period over which lamprey embryos are available can be maximized even with a limited supply of breeding stock. In addition, a detailed account of lamprey handling and housing are included for those considering using this animal for the first time.
Comparative histology of the scolex and neck region of Glaridacris laruei (Lamont, 1921) Hunter, 1927 and Glaridacris catostomi Cooper, 1920 (Cestoidea: Caryophyllidea)
Authors: Hayunga Eugene G. , Mackiewicz John S.
Published: March 2009

The histology of the scolex and neck region was examined in adults of the caryophyllidean tapeworms Glaridacris laruei and Glaridacris catostomi, parasites of the white sucker, Catostomus commersoni (Lacépède). Several distinct cell types were identified in the parenchyma including tegumental cells, flame cells, longitudinal muscle cells (myoblasts), transverse and dorsoventral muscle cells, parenchyma cells, epithelioid cells, and cells associated with the calcareous corpuscles. The proliferative zone of germinative cells reported for strobilate tapeworms was not found in these species. Faserzellen, or neck cells, which consisted of a deeply staining mass of cells, were found in the medullary parenchyma of the neck. Histochemical tests revealed that the cytoplasm of the Faserzellen was rich in RNA and protein, but alkaline and acid phosphatase activity were not detected. The arrangement of musculature in the scolex was examined; muscles associated with the attachment organs of G. laruei appear more developed compared with those of G. catostomi. Measurements of the various cells and their characteristic staining properties are presented in tabular form.
Body reserves of neonate northern pintails (Anas acuta)
Authors: Duncan David C.
Published: March 2009

Neonate northern pintails (Anas acuta) had a high lipid content primarily attributable to the fat deposits in their carcasses. Their yolk sacs contained 24% of the total lipid at hatching. In the absence of food, newly hatched northern pintails survived by catabolizing their carcass fats. The yolk sac was not an important source of endogenous nutriment under starvation conditions but appeared to be important to the growth of ducklings, contributing materials for the synthesis of nonfat tissue. The function of yolk sacs is reviewed and the body composition of neonate northern pintails is compared with that of other species in relation to the developmental maturity of the young.
Within-season and age-related patterns of reproductive performance in female tree swallows (Tachycineta bicolor)
Authors: Stutchbury Bridget J. , Robertson Raleigh J.
Published: March 2009

In many species of birds, clutch size decreases as the season progresses, but this is confounded by the fact that young birds not only often have smaller clutches but also breed later than older females. We examined the effect of time of season on clutch size, hatching success, and fledging success of female tree swallows (Tachycineta bicolor) in their second year (SY) and after their second year (ASY), and compared their reproductive performance while controlling for time of season. For both SY and ASY females, clutch size decreased significantly with later first egg dates, which caused number hatched and number fledged per brood to also decline as the season progressed. However, neither the proportion of eggs hatched nor the proportion of young fledged was correlated with first egg date. The within-season decline in clutch size was not due simply to replacement clutches or female age, and we argue that it is also not due to a decrease in food abundance over the breeding season. Age-related differences in reproductive success depended on the time of season. Early in the breeding season, ASY females were superior to SY females in every measure of reproductive performance; however, there were no significant differences between age-classes late in the season. ASY females were more successful than SY females in raising clutches of five or six eggs, which were most common early in the season, but there was no difference between age-classes in raising clutches of four eggs. We suggest that an age-related difference in foraging efficiency and within-season changes in the cost of competition could explain this pattern.
On the identity of six Berlese species of Macrocheles (Acari: Macrochelidae): descriptions, redescriptions, and new synonymies
Authors: Krantz G. W.
Published: March 2009

Redescriptions of five Berlese species of Macrocheles are presented, and synonymies are established for M. elimatus (= M. inornatus Evans and Hyatt) and M. longipes (= M. nemontanus Ryke and Meyer). Macrocheles hirsutissima Berlese sensu Evans and Hyatt (1963) is redefined as a new species (Macrocheles laciniatus), and M. hirsutissima is redescribed. Macrocheles spinipes Berlese, which is phoretic on a phytophagous scarab, is redescribed and compared with M. grossipes Berlese, a closely related, co-occurring coprophilous species. Finally, M. peregrinus Krantz is discussed in terms of its possible synonymy with M. aethiopicus Berlese, originally described as a subspecies of M. alecto.