bluuebunny/crossref_metadata_2025 huggingface dataset:
Hematological and parasitological study of the Iriomote cat (Prionailurus iriomotensis)
Authors: Akuzawa Masao , Mochizuki Masami , Yasuda Nobuhiro
Published: March 2009

Hematological and serum biochemical analyses, serum toxoplasma antibody detection, and a fecal parasite survey were carried out in nine male and eight female adult Iriomote cats (Prionailurus iriomotensis). This species was first found in 1965 and was described as a new genus and species of cat more closely related to the extinct taxon Nimravinae than to other extant felids. Values of blood parameters were similar to the normal values in domestic cats. Three trematodes, two cestodes, eight nematodes, and two coccidia were found in feces, and antibody to Toxoplasma gondii was detected in the serum of 4 of 16 cats examined.
Comparison of [D-Arg6, Trp7, Leu8, Pro9NEt]-luteinizing hormone-releasing hormone (sGnRH-A), and [D-Ala6, Pro9NEt]-luteinizing hormone-releasing hormone (LHRH-A), in combination with pimozide, in stimulating gonadotropin release and ovulation in the goldfish, Carassius auratus
Authors: Peter R. E. , Sokolowska M. , Nahorniak C. S. , Rivier J. E. , Vale W. W.
Published: March 2009

LHRH-A and sGnRH-A were tested, in the presence or absence of pimozide (Pim), for their ability to stimulate increases in serum gonadotropin (GtH) levels and ovulation in prespawning female goldfish. In the absence of Pim, sGnRH-A was more active than LHRH-A in terms of stimulating serum GtH levels; neither peptide given alone was effective in stimulating ovulation. Pim potentiated the activity of both peptides; high dosages of either peptide, plus a high dosage of Pim, were highly effective in stimulating serum GtH and ovulation. A low dosage of sGnRH-A, plus a low dosage of Pim, were also effective in stimulating serum GtH and ovulation; however, a low dosage of LHRH-A plus a low dosage of Pim were ineffective. The time to ovulation following injections, for those treatments that were highly effective in inducing ovulation, was highly predictable, and oocyte fertility and viability were high. These results indicate that sGnRH-A, in the presence of Pim, is effective in stimulating ovulation in goldfish at dosages about 10-fold less than for LHRH-A. The basis for the differences in potency between sGnRH-A and LHRH-A is discussed.
Changes in web-monitoring forces associated with web reduction in the spider family Uloboridae
Authors: Opell Brent D.
Published: March 2009

Members of the genera Uloborus, Hyptiotes, and Miagrammopes have similar web-monitoring postures, but very different webs and tactics for monitoring them. Orb weavers of the genus Uloborus construct horizontal webs and hang from their hubs, whereas reduced-web uloborids construct vertical webs and monitor them from a single thread. To determine if changes in spider strength accompanied web reduction, resting and maximum force measurements were taken of a developmental series of Hyptiotes cavatus, Uloborus glomosus, Miagrammopes animotus, Miagrammopes pinopus, and an undescribed Costa Rican Miagrammopes using a glass needle strain gauge. Both carapace length and spider weight were used as indexes of spider size. Regression analyses of forces show that H. cavatus exerts the greatest relative force and Miagrammopes species the least. This is consistent with requirements for the operation of each web type: Hyptiotes cavatus tenses its entire triangular web and suddenly releases this tension when a prey strikes its web, whereas a Miagrammopes species jerks a single thread that has captured a prey. Within the genus Miagrammopes, the species with the most highly modified carapace expressed the greatest resting force.
The mechanics of annual changes in ptarmigan numbers: a reply to Bergerud, Mossop, and Myrberget
Authors: Watson Adam , Moss Robert
Published: March 2009

In their review, Bergerud et al. (Bergerud, A. T., Mossop, D. H., and Myrberget, S. 1985. Can. J. Zool. 63: 2240–2248) evaluated two hypotheses to explain changes between years in the number of breeding ptarmigan (Lagopus spp.): "(i) numbers are limited by territorial spacing behaviour (Watson and Moss 1972) [Watson, A., and Moss, R. 1972. Proc. Int. Ornithol. Congr. 15: 134–1491 and (ii) numbers change in response to annual variations in breeding success." Several of the general definitions or views that they proposed are theoretically unsound or ambiguous, and certain specific statements inaccurate. After stating that "the primary implication of the breeding success hypothesis, namely that chick survival to autumn will be reflected in the next year's population, is not a mutually exclusive test" and after giving no mutually exclusive test themselves, they went on to use the invalid test of a correlation between changes in numbers and breeding success as if it were mutually exclusive. The reviewers' conclusions are based largely on correlations of past measurements. Putting the two hypotheses to the test by experiments is likely to be a more reliable way forward.
Fourth International Theriological Congress/Quatrième congrès international du thériologie: Introduction
Authors: Fuller W. A.
Published: March 2009

The Fourth International Theriological Congress was held on the campus of the University of Alberta, Edmonton, from August 13 to 20, 1985. Registrants (907) came from every province and both territories of Canada, and from 51 other countries. The scientific program consisted of 5 plenary lectures, 29 symposia, 20 workshops, and 3 evenings of films. The total number of communications exceeded 700. Topics covered nearly all aspects of mammalogy from Cretaceous fossils to molecular genetics of recent mammals.Publication of contributions to symposia and workshops was left to the discretion and energy of the organizers of each session. The Congress Secretariat undertook to publish abstracts of all communications received before the press deadline (682), as well as the plenary addresses. One of the plenary speakers declined to submit a manuscript on the grounds that all of the information had already been published. A second paper has already been published (Mares, M. A. 1986. Conservation of neotropical mammals. Science (Washington, D.C.), 233: 734–739). The remaining three plenary papers appear as a group in this issue of the Canadian Journal of Zoology.
Hydrodynamic drag of two frog species: Hymenochirus boettgeri and Rana pipiens
Authors: Gal Julianna M. , Blake R. W.
Published: March 2009

Drag of the aquatic frog Hymenochirus boettgeri was investigated by a series of drop-tank and flow visualization experiments. The maximum drag coefficient (CD) of the body and hind limbs was 0.24–0.11, for a Reynolds number (Re) of 1500–8000. Results of the flow visualization experiment support the CD values obtained for the body and hind limbs of H. boettgeri. CD similarly measured for Rana pipiens was 0.060–0.050, for a Re range of 16 600 – 40 400. A comparison of CD under dynamically similar conditions suggests that jumping may not compromise swimming performance in these two species. CD for the foot of H. boettgeri was examined by three methods: drop-tank experiments with isolated frog's feet and with isolated acetate model feet, and a subtraction method. CD for the isolated foot was 2.5–1.6 for 100 < Re < 700. Results were similar to those obtained with isolated model feet, where 1.8 > CD > 1.2 for 300 < Re < 1300. The subtraction method gave similar results to those obtained from drop-tank experiments with isolated model and real feet, within the Re range of 300–3000. The results of all three methods and flow visualization experiments support the assumption that animal paddles can be treated as three-dimensional flat plates, oriented normal to the direction of flow.
Long-term reproductive patterns and sighting bias in Weddell seals (Leptonychotes weddelli)
Authors: Testa J. Ward
Published: March 2009

The reproductive performance of tagged Weddell seals (Leptonychotes weddelli) was monitored at McMurdo Sound, Antarctica, from 1970 to 1984. An age-specific reproductive schedule revealed the major onset of pupping at age 6 years, and a mean age of first birth of 7.1 years. The average asymptotic pupping rate of 0.61 is reached by age 10. The cost of pupping in a given year is reflected in a 0.05 drop in the probability of pupping the following year. This cost is not evident in females over 7 years old, suggesting that postweaning condition affects newly mature females more than those that are fully mature. Annual adult reproductive rates ranged from 0.46 to 0.79, with a possible periodicity of 5 to 6 years. Simulations were conducted to determine the impact on reproductive estimates of sighting biases associated with seals having had at least one pup (Parous) or having pupped that season (With-Pup). Age at first reproduction as deduced from an age-specific pupping schedule is strongly affected by both forms of sighting bias, but bias in sighting Parous females was the more important. Estimates of adult reproduction were affected minimally. Comparisons of reproductive estimates with those of Weddell seals at Signy Island are discussed with regard to the effects of sighting biases.
Habitats, food resources, and natural enemies of a community of larval Cicindela in southeastern Arizona (Coleoptera: Cicindelidae)
Authors: Knisley C. Barry
Published: March 2009

This study examines food resources, natural enemies, and natural history of three cohorts of larvae of eight Cicindela species from seven habitats in southeastern Arizona. Larvae of most species occurred with adults in the same habitats. Pond and ditch edge habitats had low soil desiccation, no parasitism, and significantly more food than other habitats. Playa species were heavily parasitized (24.1–44.2%) by a bombyliid fly (Anthrax). Sand ridge, saltbush flat, and grassland species experienced little food, moderate to heavy parasitism by a tiphiid wasp, Pterombrus rufiventris, and occasional soil desiccation. Pond and ditch edges had much higher larval densities than other habitats. However, relative to adults, few species were present. Survivorship (first instar to adult) was low for all species [Formula: see text]. Reduced activity during midday was correlated with high burrow surface temperatures. Seasonal activity varied from 8 to nearly 12 months. Life cycles ranged from 1 to 4 years with 2 years most common. Food is an apparent limiting resource for most species. Larval habitat, life cycle, and size all may influence rates of parasitism.
Genetic basis of variation in morphometric characters as implied by hybrids between subspecies of Esox americanus (Pisces: Esocidae)
Authors: Reist James D. , Crossman E. J.
Published: March 2009

Artificial hybrids between Esox americanus americanus and Esox americanus vermiculatus, reared in a common laboratory environment, scored intermediately in discriminant analysis to the distribution of scores of reference parental samples. This implies a genetic basis for the variables that differ between the subspecies. Such intermediacy also provides a test of the utility of discriminant function analysis in such analyses. Scores of putative intergrade specimens from Alabama overlapped those of E. a. vermiculatus, indicating our incomplete understanding of the intergradation between these two forms.
Spatial distribution of the parasite Kroyeria carchariaeglauci Hesse, 1879 (Copepoda: Siphonostomatoida: Kroyeriidae) on gills of the blue shark (Prionace glauca (L., 1758))
Authors: Benz George W. , Dupre Kevin S.
Published: March 2009

Five blue sharks (Prionace glauca) were examined for gill-infesting copepods. Three species of siphonostomatoid copepods were collected: Gangliopus pyriformis, Phyllothyreus cornutus, and Kroyeria carchariaeglauci. The spatial distribution of K. carchariaeglauci was analyzed. The number of K. carchariaeglauci per shark was positively related to gill surface area and host size. Copepods were unevenly distributed amongst hemibranchs; flanking hemibranchs could be arranged into three statistically homogeneous groups. Female K. carchariaeglauci typically attached themselves within the middle 40% of each hemibranch; males were more evenly dispersed. Eighty percent of all K. carchariaeglauci attached themselves to secondary lamellae, the remainder were in the underlying excurrent water channels. Most K. carchariaeglauci were located between 10 and 25 mm along the lengths of gill filaments. Overall, the spatial distribution of K. carchariaeglauci was quite specific in all study planes. Explanation of this distribution is set forth in terms of natural selection pressures; however, the equally plausible explanation that the distribution pattern exhibited by these copepods is phylogenetically determined and may have little to do with contemporary selective constraints should not be ignored.
Natality and weaning success in relation to age of first reproduction in northern elephant seals
Authors: Huber Harriet R.
Published: March 2009

Reproductive histories of female northern elephant seals (Mirounga angustirostris) tagged as pups at the Farallon, Año Nuevo, San Miguel, and San Nicolas islands were followed on the Farallon Islands, California, from 1975 to 1983. Age of primiparity ranged from 3 to 6 years. Females that first reproduced at age 4 or 5 had significantly higher subsequent natality and weaning success than did females first giving birth at 3 years. However, no difference in weaning success was evident between primiparous and experienced 4- and 5-year-olds. The number of primiparous 3-year-old animals that skipped pupping the following year was significantly higher than the number of primiparous 4-year-old animals that skipped the following year. Overall subsequent natality by parous females (both known-age and females tagged as adults) followed for 4 consecutive years averaged 0.86. On average, 14% (range 8 to 20%) of parous females did not give birth each year. Some of the females that skipped pupping hauled out in the fall with immature animals and some were present at breeding rookeries during the season of their missed pupping only to copulate. From 1974 to 1977, the number of pups born increased an average of 60% each year; however, from 1978 to 1983 the rate decreased to 25%. Most population growth was due to immigration. The range in age of parous females increased from 3 to 5 years in 1975 to 4 to 13 years in 1983.
Description of Gyrodactylus micropteri n.sp. from Micropterus dolomieui in Lake Huron, with a review of the taxonomy of species of Gyrodactylus (Monogenea) parasitizing centrarchid fishes in North America
Authors: Nicola K. J. , Cone D. K.
Published: March 2009

An extensive collection of Gyrodactylus from centrarchid fishes in Ontario is examined. Gyrodactylus goerani Hanek and Fernando, 1971 is recorded from Ambloplites rupestris in Lake Ontario and Lepomis gibbosus, Lepomis macrochirus, and Pomoxis sp. in Lake Erie. Gyrodactylus macrochiri Hoffman and Putz, 1964 is recorded from L. gibbosus in Algonquin Park. Gyrodactylus micropteri n.sp. is described from Micropterus dolomieui in Lake Huron. The new species has a marginal hook sickle with a blade that toward its tip curves substantially inward. Examination of type specimens of G. goerani, G. macrochiri, and three other species specific to centrarchid fishes in North America (Gyrodactylus gloriosi Rogers, 1968, Gyrodactylus heterodactylus Rogers and Wellborn, 1965, and Gyrodactylus lineadactylus Wellborn, 1967) revealed that the original species descriptions are inadequate with respect to the diagnostically important marginal hook sickles. The haptoral sclerites of these species are redrawn.
A survey of the parasites of nonanadromous and anadromous brook charr (Salvelinus fontinalis) in the Tabusintac River, New Brunswick, Canada
Authors: Frimeth Jack P.
Published: March 2009

A parasite survey of 1146 brook charr (Salvelinus fontinalis) was conducted between January 1981 and December 1982 in the Tabusintac River, New Brunswick, Canada. A total of 36 parasite species were recovered, of which 18 (one Myxosporea, two Monogenea, three Digenea, three Cestoidea, five Nematoda, one Acanthocephala, one Hirudinoidea, one Crustacea, and a Dermocystidium sp.) were freshwater and 18 (two Monogenea, seven Digenea, two Cestoidea, two Nematoda, two Acanthocephala, and three Crustacea) were marine. Anadronomous charr were differentiated from nonanadromous charr in fresh water by the presence of marine parasites. Charr in the estuary and lagoon were all considered to be anadromous; however, first-time anadromous charr or smolts were differentiated by the absence of marine parasites and infection with freshwater parasites only. New host records include Lecithaster gibbosus, Zoogonus lasius, Podocotyle angulata, Cryptocotyle lingua (metacercariae), Stephanostomum tenue (metacercariae, adults), Eubothrium crassum, Tetraphyllidea gen. sp. (plerocercoids), Eustrongylides sp. (larvae), Hysterothylacium aduncum (larvae, adults), Corynosoma magdaleni (juveniles), Argulus alosae, and Ergasilus labracis. Zoogonus lasius and Stephanostomum tenue represent new Canadian records, and Chloromyxum truttae and Truttaedacnitis truttae are reported for the first time from New Brunswick. Bulbodacnitis alpinus, previously reported only from the Arctic charr (Salvelinus alpinus), is considered to be a synonym of T. truttae.
Brood territories in buffleheads: determinants and correlates of territory size
Authors: Gauthier Gilles
Published: March 2009

In most species of ducks, only females tend the brood, and they do not defend brood territories. However, in buffleheads (Bucephala albeola), females strongly defend brood territories. I examined factors affecting territory size of broods, and their consequences for growth rate and survival of ducklings. Brood density tended to be higher on ponds with higher food density. Territory size was inversely correlated with both food abundance in the territory and brood density on the pond. The slope of the relationship between territory size and food did not differ significantly from −1, the slope expected if females adjust territory size to maintain a constant food supply. Partial correlation analysis, however, revealed that brood density may be a more important proximate determinant of territory size than food. Growth rates of ducklings were not affected by food density but were depressed at high brood density in one year. Duckling survival increased with food density in the first year but was depressed at high brood density in the next. I suggest that females select a brood territory and that the size of that territory varies according to both food and brood density. This apparently buffers the effects of variation in food and brood density on growth and survival of ducklings.
Adaptations for marsh nesting in common and Forster's terns
Authors: Storey Anne E.
Published: March 2009

Salt marsh colonies of common terns (Sterna hirundo) appear to be increasing along the east coast of the United States, particularly in areas where there is heavy use of their traditional barrier beach habitat by humans. The potential for successful marsh nesting by common terns was examined by comparing their nesting requirements with those of marsh-nesting Forster's terns (S. forsteri). The comparison focused on nest survival of tidal inundation, the major source of nest loss for marsh-nesting birds. Both species typically build short nests, which are usually elevated on mats of dead vegetation. Forster's tern nests were on lower ground, on higher mats, and in taller grass than were common tern nests. The lower ground at Forster's tern nests is offset by higher mats, and total nest height above mean high water is the same for both species. The high grass and low ground at Forster's tern sites resembles those of other typically marsh-nesting species, and offers more protection from tides that exceed nest height, because high grass helps to hold the mat and nest in place. Forster's terns renested more quickly after flooding, produced larger replacement clutches, and hatching occurred at a higher proportion of late nests compared with common terns. These differences suggest that Forster's terns are better adapted to the frequent necessity to renest in the salt marsh. Species differences in nest sites do not appear to be the result of interspecific competition, but rather may reflect different responses of the two species to water around the nest site during the period of nest site selection.
An analysis of gizzard worm infections in fall migrant ducks at Delta, Manitoba, Canada
Authors: McLaughlin J. Daniel , McGurk Brian P.
Published: March 2009

Gizzards from 13 species of ducks collected during the 1979 hunting season at Delta, Manitoba, Canada, were examined for helminths. Of the 1196 gizzards examined, 77.7% harbored at least one species of helminth. Amidostomum acutum occurred in 53.3% of the gizzards (13 species); Epomidiostomum uncinatum, in 28.5% (10 species); Streptocara crassicauda, in 18.1% (12 species); Gastrotaenia cygni, in 17.8% (11 species); and Streptocara formosensis, in 3.7% (5 species). Infection levels in juveniles and adults and in males and females of the same age in each species were generally similar. Prevalence and abundance of A. acutum in dabbling ducks (Anas spp.) was greatest among species exhibiting intermediate or generalist foraging tactics. Redheads and canvasbacks had the heaviest infections among diving species. The intermediate and generalist Anas species also had the greatest prevalence and abundance of E. uncinatum. With the exception of ruddy ducks, divers were rarely infected with this helminth. Lesser scaup were the major hosts for the Streptocara species and prevalence in other hosts tended to reflect the importance of amphipods in the diet. Shovelers, which feed extensively on zooplankton, had the highest prevalence of G. cygni. Few significant differences were found in the mean intensity of each helminth among host species despite wide differences in prevalence. Thus while diet and (or) foraging strategy may affect a species' contact with the infective pool, it apparently has little effect on the size of the infection which results.
Influence of photoperiod and temperature on hatching and emergence of Baltic salmon (Salmo salar L.)
Authors: Brännäs Eva
Published: March 2009

The influence of photoperiod and temperature on hatching and emergence of Salmo salar L. was studied experimentally. Eggs were taken from a hatchery-reared Umeälven (Ume River) stock in northern Sweden (63°50′ N, 20°05′ E). Eggs kept in a light regime of 16L: 8D hatched mainly during the light period while eggs kept under conditions of no light hatched continuously over a 24-h period. Emergence of alevins from simulated redds kept under different LD regimes (light > 4 h) was well synchronized with the dark periods: the largest number of alevins left the gravel during the 1st h of darkness. In continuous darkness alevins exhibited a tendency for a persistent emergence pattern, i.e., the pattern resembled the photoperiod cycle to which they were previously exposed. Neither the length of the yolk sac phase nor the length of the emergence period among alevins was affected by photoperiod. In cold water (6.0 and 11.5 °C) emergence was mainly nocturnal. At high temperature (14.5 °C) the diel pattern of emergence switched and a major proportion of alevins left the gravel during the hours of light. In addition, at high temperatures the alevins spent a shorter time in the substrate and emerged during a short period of time compared with alevins emerging in cold water. The ecological implications of the influence of ambient temperature and photoperiod on emergence are discussed.
Octopamine-mediated elevation of cyclic AMP in haemocytes of the American cockroach, Periplaneta americana L.
Authors: Gole J. W. D. , Orr G. L. , Downer R. G. H.
Published: March 2009

The injection of 10 μL of 5 × 10−3 M octopamine into the haemocoel of adult male Periplaneta americana results in a 20 × increase in haemolymph cyclic AMP (cAMP) levels within 3 min. Synephrine also causes a marked increase in haemolymph cAMP, and less pronounced elevations were obtained following the injection of tyramine, dopamine, norepinephrine, 5-hydroxytryptamine, phenylethanolamine, β-phenylethylamine, and L-phenylephrine. The octopamine effect is time dependent for at least 10 min and dose dependent with the EC50 for the injected dose calculated to be about 2.5 × 10−3 M. These results indicate that the octopamine response is receptor mediated and studies on isolated haemocytes suggest that the octopamine-sensitive receptors are located on haemocytes. Incubation of whole haemocytes in medium containing octopamine results in a dose-dependent elevation of cAMP with the EC50 calculated at about 7.5 × 10−6 M. Synephrine, tyramine, and dopamine also elevate cAMP levels in incubated haemocytes, and the activator of adenylate cyclase, forskolin, causes a marked increase in cAMP. The octopamine-mediated response is blocked by mianserin, phentolamine, and cyproheptadine but not by the β-adrenergic blocking agents propranolol and dichloroisoproterenol.
Ocean pout (Macrozoarces americanus (Bloch and Schneider) (Pisces: Zoarcidae)) predation on green sea urchins (Strongylocentrotus droebachiensis (O.F. Mull.) (Echinodermata: Echinoidea)) in eastern Newfoundland
Authors: Keats D. W. , Steele D. H. , South G. R.
Published: March 2009

The diet of ocean pout was studied by analysis of the contents of the gastrointestinal tracts of 151 individuals collected from the green sea urchin dominated rocky subtidal in eastern Newfoundland. Green sea urchins constituted 62% of the overall diet by weight. The brittle star, Ophiopholus aculeata, constituted 7% of the diet, while the remainder was miscellaneous invertebrates and fish (mainly capelin and billfish). From April to July, when the fish are inshore and feeding, before breeding, the average ocean pout contained 56.3 g of urchins. This is a biomass of urchins equivalent to that in 0.106 m2 of the middle of the urchin-dominated zone. During the inshore feeding period, the average male ocean pout contained 65.0 g of urchins, and the average female contained 47.5 g, biomass values representing 0.122 and 0.089 m2, respectively. Assuming that the contents of the gastrointestinal tract turn over every 3 days, and assuming a 1:1 sex ratio, it is calculated that while inshore, before a seasonal reduction in feeding associated with the spawning season, each ocean pout consumes on average 2.29 kg of urchins (males 2.64 kg, females 1.93 kg). Based on these figures, a density of one ocean pout pair per 8.6 m2 would be required to completely consume the mean biomass (532 g m−2) of urchins present in the urchin-dominated zone in one season.
The vasculature of the white bodies in the ommastrephid squid Illex illecebrosus (LeSueur, 1821): a proposed route for the dissemination of newly formed hemocytes
Authors: Johnson F. Elizabeth
Published: March 2009

The vasculature of the white bodies within Illex illecebrosus (LeSueur, 1821) was investigated by employing arterial injections of latex and RENOgrafin-60 (a radiopaque dye) and light, electron, and scanning electron microscopy. The information obtained from these various methods indicates that the white bodies are well supplied with blood. Blood flows to a white body by way of the anterior and posterior ophthalmic arteries; passes through its tissue via small vessels, sinuli, and hemal spaces; and eventually leaves the tissue to enter the enveloping optic sinus (and hence, the venous circulation) by way of hemooscula, here described for the first time. These data have been employed to determine the route for the dissemination of the newly formed hemocytes, which evidence suggests originate in the white bodies. Furthermore, this elucidation of the vasculature provides a means of assessing both the multilobate configuration of the white bodies and the rationale for the latter's position on the medial surface of the squid's eye.
Tooth microwear and diet in the African Viverridae
Authors: Taylor Mark E. , Hannam Alan G.
Published: March 2009

Distinct tooth microwear patterns were observed in viverrids (Carnivora). Epoxy replicas of the upper tooth row of 32 specimens of 12 species of African viverrids were prepared and examined using a scanning electron microscope. Four general patterns emerged: (i) teeth with deeply scored grooves and scratches predominantly in the vertical direction, (ii) teeth with a preponderance of pits with little grooving or scratching, (iii) teeth with both pits and grooves, and (iv) teeth with lighter grooves running in both the vertical and horizontal directions. Microgrooves and scratches seemed to occur primarily in species that eat vertebrate food items while pitting appeared to occur mainly in those that eat invertebrate prey. The horizontal grooves are probably caused by the predator using the carnassial as a rake to remove flesh from prey while holding it between the forefeet.
The effect of captivity on reproduction and development in Peromyscus maniculatus
Authors: Millar John S. , Threadgill Debbie A. L.
Published: March 2009

Artificial selection for high productivity (early maturation and large litters) early in life was maintained in a laboratory colony of Peromyscus maniculatus nebrascensis for 11 generations. A comparison of reproductive and developmental characteristics in this colony indicated that some traits, such as weight of females, age at maturation, and litter size, did not change over generations. However, other traits did change. An initial increase in the proportion of pairs breeding was offset by the inability of females to successfully raise their offspring. Weight of offspring was larger among wild females than among females born in captivity, although weight of offspring was not different between early and late generations in captivity. The relationship between offspring weight and litter size also differed between wild and laboratory-born females. We conclude that data derived from laboratory stocks do not necessarily reflect patterns exhibited by mice in natural populations. We recommend that generations in captivity be treated as a covariate in comparisons among laboratory stocks and that the interrelationships among reproductive and developmental traits be examined under natural conditions.
Studies on the reticuloendothelial system of the dogfish Scyliorhinus canicula. Endocytic activity of fixed cells in the spleen and liver
Authors: Hunt Timothy C. , Rowley Andrew F.
Published: March 2009

The role of the spleen and liver of the lesser spotted dogfish, Scyliorhinus canicula, in the clearance of a range of materials, including colloidal carbon, latex beads, sheep red blood cells, bacteria, and dextran, was examined. The spleen was particularly important in the clearance process. Smaller particulates, such as carbon, were sequestered by the highly endocytic macrophages of the ellipsoids, while larger particles, for example, bacteria and sheep red blood cells, were mainly taken up by the fixed macrophages of the red pulp. An increase in the numbers of the eosinophilic G1 granulocytes in the red pulp of the spleen was observed following injection of the particulates. In the liver, fixed cells, probably homologous to mammalian Kupffer cells, were involved in clearance and participated in endocytosis of carbon and latex. Additionally, all of the injected particulates were internalized by cells (frequently seen to also contain melanin granules) lying within nonsinusoidal blood vessels in the hepatic parenchyma. Often, but especially in fish injected with bacteria, these phagocytic cells appeared trapped along with free bacteria, within large clumps of circulatory blood cells in the vessels. The presence of the injected materials in the spleen and liver was evident at 30 min and increased up to 1 week. The ultimate localization and differential uptake of the injected materials, and the relative importance of the spleen and liver in the clearance of these materials are discussed.
Digestive organ morphology, diet, and guild structure of North American Anatidae
Authors: Barnes Gregory G. , Thomas Vernon G.
Published: March 2009

Discriminant function, cluster, and covariate analyses of gizzard, small intestine, and ceca weights were used to quantify the structure of feeding guilds and the effects of diet on gut morphology for 18 species of North American anatids. Guild structure based on gut measurements closely approximated that identified by generalized feeding habits. Herbivorous species such as Brant (Branta bernicla), Gadwall (Anas strepera), Redheads (Aythya americana), Canada Geese (Branta canadensis), and Mallards (Anas platyrhynchos) consistently had heavier gizzards and ceca than carnivorous species such as Common Goldeneye (Bucephala clangula), Bufflehead (Bucephala albeola), Oldsquaw (Clangula hyemalis), and Common Mergansers (Mergus merganser). Omnivorous species such as Lesser Scaup (Aythya afftnis), Greater Scaup (Aythya marila), and American Black Ducks (Anas rubripes) were characterized by heavy gizzards, intermediate ceca, and heavy intestines. The results provide further evidence that intestine size is primarily influenced by overall diet diversity and suggest that gut size may be used to indicate general food habits. The ability of waterfowl to adjust gut sizes and accommodate dietary changes is restricted to ranges dictated by the most frequently eaten foods. Thus, predictions of general food habits can be made without knowledge of the foods being consumed at a particular time and location.
Electrophoretic divergence of Myotis leibii and Myotis ciliolabrum (Chiroptera: Vespertilionidae)
Authors: Herd Robert M.
Published: March 2009

Myotis ciliolabrum has recently been recognised as a species distinct from Myotis leibii. Electrophoretic divergence between the two species exceeds that of subspecies of other bats and is similar to that found between other species. Fixed allelic differences at two loci suggested that no introgression occurs. The electrophoretic data support the conclusion that M. ciliolabrum and M. leibii are distinct species.
Factors influencing winter food choice by mountain hares (Lepus timidus L.) on Swedish coastal islands
Authors: Angerbjörn Anders , Pehrson Åke
Published: March 2009

In mainland areas, mountain hares seem unable to survive on a single browse species. However, mountain hares on islands off the west coast of Sweden rely almost entirely on a plain heather diet during winter. Herein, we give as a possible explanation for this phenomenon that the high concentration of sodium in the heather in the coastal areas can buffer the high sodium excretion otherwise observed in hares feeding on heather under experimental conditions. Furthermore, hares selected heather with the highest nitrogen and phosphorus contents. We argue that the pattern of food choice exhibited by the hares in the coastal area is to be expected in homogenous habitats where hares rely on one dominant food species. In heterogenous habitats, the possibility of food selection on a nutritional level is to a considerable extent overridden by effects of digestibility and concentration of secondary compounds in the different food plants available.
Movements and behavior of migratory garter snakes, Thamnophis sirtalis
Authors: Larsen Karl W.
Published: March 2009

Although garter snake populations in northern areas have been shown to undergo annual migrations, no detailed information has been available on these movements. Through biotelemetry and, to a lesser extent, mark–recapture methods, the migration of an extreme northern population of Thamnophis sirtalis was documented. Snakes emerging from a hibernaculum moved towards the closest freshwater marsh, which was approximately 3.75 km away. Radio-tracked individuals moved along a constant bearing; once they reached the proximal regions of the marsh, they continued to move away from the den, but circled back during the later part of the summer. One individual completed a round trip of over 15 km during one active season. Snakes routinely exhibited a distinct behavioral sequence during the daily travels, and five rather lengthy searches for overnight retreats were observed. The extensive migration documented in this study may be quite costly for the northern snakes, for (i) it may significantly decrease the time available for other important activities, such as feeding, and (ii) it increases the snakes' exposure to the adverse spring and fall weather conditions, which in turn may subject them to predation or lethal temperatures.
Effects of ganglion extracts on chloride-dependent electrical potentials and short-circuit currents across the mantle epithelium of Achatina fulica
Authors: Enyikwola O.
Published: March 2009

The left parietal and visceral ganglia of the giant African snail, Achatina fulica, and also nerves leading from them contain a compound that stimulates chloride-dependent electrogenesis by the mantle epithelium. Release of the substance in vitro is stimulated by 5–12 mM K+, provided Ca2+ is present. The active substance is inactivated by trypsin and prolonged heating, but not by brief heating or lipase. The electrical gradient was unaffected by adrenaline, acetylcholine, cyclic AMP, dibutyryl cyclic AMP, 5-hydroxytryptamine, or thyrotropin releasing factor. However, theophylline inhibited electrogenesis. It is suggested that the electrogenic transport of chloride by the mantle of Achatina may be under neuroendocrine control.
The identification and morphological variation of Diplostomum baeri bucculentum from two gull species, using metacercarial infections from least cisco from the Northwest Territories
Authors: Shostak Allen W. , Tompkins Jean C. , Dick Terry A.
Published: March 2009

Metacercariae of the genus Diplostomum, recovered from the eyes of the least cisco, Coregonus sardinella, were used to experimentally infect chicks of ring-billed gulls, Larus delawarensis, and herring gulls, Larus argentatus. Adults recovered from the intestine of these gulls were identified as Diplostomum baeri bucculentum based on size characteristics and the position of the anterior margin of the vitellaria to at least the level of the ventral sucker. An analysis of morphological characters from 258 gravid specimens showed a greater range in measurements than previously reported for this species. Moreover, characters such as egg numbers and size and shape components were strongly influenced by host effects. There does not appear to be the extensive geographic variability in morphology that is known for other helminth groups.
New Carboniferous Diplura, Monura, and Thysanura, the hexapod ground plan, and the role of thoracic side lobes in the origin of wings (Insecta)
Authors: Kukalová-Peck Jarmila
Published: March 2009

A new Upper Carboniferous japygid, Testajapyx thomasi n.gen. et n.sp., shows that only Diplura of Entognatha shared an ancestral ground plan with Insecta–Ectognatha. Pleuron, palps, thoracic and abdominal legs, and vesicles are compared between Diplura, Archeognatha, Monura, Thysanura, and Pterygota. The origin and evolution of side lobes on the head, thorax, and abdomen, and of cereal legs, cerci, and posttarsal (=pretarsal) claws are considered. The paleoenvironment of the earliest insects and its impact on evolution of thoracic side lobes is discussed. Consistent evidence from several biological disciplines shows that protowings evolved from thoracic side lobes, which probably originated from serial, articulated outer appendages (=exites) of the arthropodan leg. Exites were continuously active and functional and became preadapted for flapping movements. Flight developed as the pterygotes diversified. Basic wing structures are monophyletic. Flight adaptation was finished and differences in wings arose somewhat later, by various means and in parallel, in already diversified lineages of Pterygota.
Foraging characteristics of Canada geese on the Nisutlin River delta, Yukon
Authors: Coleman T. S. , Boag D. A.
Published: March 2009

Food selection by Canada geese (Branta canadensis), staging in the autumn on the Nisutlin River delta in the south central Yukon Territory, was investigated between August and October of 1981, 1982, and 1983. Three distinct plant associations were used by the foraging geese: an aquatic association in which rhizomes of Potamogeton richardsonii, the dominant species, were eaten; a terrestrial and more vegetatively complex association in which Equisetum palustre was the main plant taken; and an association of almost pure stands of Equisetum fluviatile in wet depressions behind old river levees. Availability of these feeding zones depended on water levels on the delta. When water levels were low (October 1982), all feeding zones were available, yet the geese fed almost entirely in the Potamogeton zone, indicating a preference for that zone. At intermediate water levels, Potamogeton richardsonii was no longer available and the geese grazed on the complex vegetative zone, taking Equisetum palustre, Ranunculus reptans, and Eleocharis palustris in the ratio of their relative availability (85:10:5). Only when water levels were high did the geese graze exclusively in the Equisetum fluviatile zone, the least preferred.
Relative fertility in hybridization experiments using three song types of the held crickets Gryllus integer and Gryllus rubens
Authors: Smith Cynthia J. , Cade William H.
Published: March 2009

Species-specific calling songs of male field crickets attract conspecific females. Each wing closure results in a pulse of sound, and the song is composed of pulses arranged in species-specific patterns of short chirps, long continuous trills, or intermediates between chirps and trills. California Gryllus integer has a song with pulses of sound delivered in groups of two or three to produce a chirp, but in central Texas, the G. integer song has a variable number of pulses delivered in long continuous trills. Gryllus rubens occurs from eastern Texas to Florida and has a trilling song with a slower pulse rate than that of Texas G. integer. Identification of these three groups in the laboratory was confirmed by recording and analyzing songs for California and Texas G. integer and G. rubens males. All possible crosses were performed in the laboratory between conspecifics and heterospecifics. No progeny resulted in California G. integer and Texas G. integer or California G. integer and G. rubens crosses. Hybrids were produced in G. rubens and Texas G. integer crosses. Results suggest that California and Texas G. integer are different species, or at least populations geographically separated enough to result in reproductive incompatibility and different song types. Texas G. integer and G. rubens are apparently closely related species.
Occurrence of Heteropolaria lwoffi (Fauré-Fremiet, 1943) and Apiosoma piscicola Blanchard, 1885 (Ciliata) on Salvelinus fontinalis (Mitchill) in Nova Scotia, Canada
Authors: Cone D. K. , Odense P. H.
Published: March 2009

Heteropolaria lwoffi (Fauré-Fremiet, 1943) and Apiosoma piscicola Blanchard, 1885 (Ciliata) are reported from fry of Salvelinus fontinalis (Mitchill) at a fish farm in Nova Scotia. The specimens were examined with a scanning electron microscope. Heteropolaria lwoffi attached to pore walls of mucous cells. Apiosoma piscicola had an affinity for the attached scopula of H. lwoffi. Bacterial microcolonies were associated with the adhesive substance secreted by the scopulas but there was no evidence of colony expansion into the underlying skin. The study represents the first specific identifications of stalked peritrichs from salmonids in North America and the first report of A. piscicola on the continent.
Variations in the temporal spacing of Franklin's gull (Larus pipixcan) flocks
Authors: Kopachena Jeffrey G.
Published: March 2009

The temporal spacing within flights of Franklin's gulls (Larus pipixcan) was studied. The extent to which gulls formed flocks was related to the time of day and also the apparent destination of the flight. In the morning, gulls departing from a colony toward foraging sites tended not to form flocks if food resources could be located predictably. Where food resources were the least predictable, gulls departing in the morning did form flocks. An intermediate tendency to form flocks occurred for morning departures toward food sources of intermediate predictability. Arriving gulls that fed en route to the colonies had lower temporal clumping than those that flew directly to the colony. Similarly, direct flights of gulls departing toward the evening roost were characterized by high temporal clumping. The highest degree of temporal clumping occurred in flights of gulls between traditional food sites. These findings support the hypothesis that some kinds of flocking in Franklin's gulls are related to increasing the success of foraging individuals. The tendency for flights toward foraging sites whose locations were unpredictable to be somewhat dispersed suggests that flocks of intermediate density provide the greatest benefits during food search.
Effects of adults on survival and recruitment of Peromyscus leucopus
Authors: Adler Gregory H. , Wilson Mark L. , DeRosa Michael J.
Published: March 2009

A population of Peromyscus leucopus (white-footed mouse) in northeastern Massachusetts was manipulated for 3 years to determine the effects of adults on survival and recruitment. Two experimental grids were established, from which either all adult males or all adult females were removed continually. The effects of these two manipulations were compared with demography on a control grid. Manipulations had no apparent effect on breeding intensity of young, survival rates of adults, or residency rates of adults and young. Recruitment of adult males was higher on the adult male removal grid than on the control grid. Recruitment rates of adult males and of young males and young females were lower on the adult female removal grid than on the control grid. Survival rates of young males were higher on the adult female removal grid than on the control grid; this effect may have been due to either reduced adult female residency or adult male recruitment. All differences between experimental and control grids were noted only during breeding seasons. Adult males apparently limited recruitment of adult consexuals. The effects of manipulations on other measured parameters were inconclusive because of high immigration rates of adult males onto the adult male removal grid and reduced recruitment of adult males and decreased production of young on the adult female removal grid.
A note on the subfamily Chantiinae Pritchard and Baker (Acari: Phytoseiidae)
Authors: Chant D. A. , Yoshida-Shaul E.
Published: March 2009

We recently proposed a subfamily, Chantiinae Pritchard and Baker, 1962, containing the genera Chantia Pritchard and Baker, 1962 and Diadromus Athias-Henriot, 1960 in the family Phytoseiidae (Chant and Yoshida-Shaul 1986). We have since learned that the genus group name Diadromus Athias-Henriot, 1960 is preoccupied by Diadromus Wesmael (1844) (Insecta: Hymenoptera). The name Chanteius Wainstein, 1962, which was treated in our 1986 paper as a junior objective synonym of Diadromus Athias-Henriot, 1960, therefore becomes the valid name for this genus. In view of this change in nomenclature, the two genera in the subfamily Chantiinae as proposed in our 1986 paper are Chantia Pritchard and Baker and Chanteius Wainstein.We are grateful to Dr. Ian Gauld of the British Museum (Natural History) for having brought this homonymy to our attention.