bluuebunny/crossref_metadata_2025 huggingface dataset:
Predation of simulated willow ptarmigan nests: the influence of density and cover on spatial and temporal patterns of predation
Authors: O'Reilly Patrick , Hannon Susan J.
Published: March 2009

Predation of eggs is a major loss in production for many populations of grouse, yet often the identity of the predators, their pattern of search, and their impact on spacing of nests is unknown. We set out clutches of quail eggs to simulate willow ptarmigan (Lagopus lagopus) nests at three densities (100/km2, 50/km2, and 27/km2) to (i) investigate the effects of nest density and concealment on predation rates, (ii) investigate the temporal and spatial patterns of predation, (iii) identify nest predators, and (iv) compare predation rates on artificial nests and nests of willow ptarmigan. Predation on artificial nests was not dependent on density. Predation was lowest in the 1st week, when nests were covered to simulate conditions during laying, and increased in week 2. Thereafter it increased on two plots and declined on four others. Artificial nests had a higher probability of being taken by a predator if they were adjacent to a nest that had been taken previously, suggesting that predators concentrate their search in areas where they have been successful. Neither amount of cover at the nest nor distance to marker stakes influenced predation rate. Predation on artificial nests was lower than on ptarmigan nests. Red foxes (Vulpes vulpes) took most clutches at artificial nests positioned beside boards coated with petroleum jelly, followed by Arctic ground squirrels (Spermophilus parryi), and least weasels (Mustela nivalis). Artificial nests were useful for identifying potential nest predators and investigating their search patterns, but did not give a good index of the extent or temporal pattern of predation on natural nests.
Female-biased sex ratio in adults of the turtle Emys orbicularis at the northern limit of its distribution in France: a probable consequence of interaction of temperature with genotypic sex determination
Authors: Servan J. , Zaborski P. , Dorizzi M. , Pieau C.
Published: March 2009

Adult sex ratio in the turtle Emys orbicularis was determined in populations from seven ponds in Brenne (Indre, France). In all populations, the sex ratio was biased toward females. Among 290 captured animals, the male:female ratio was close to 0.5. Among different demographic factors that could affect the adult sex ratio, the most influential was probably the sex ratio of hatchlings. In Emys orbicularis, a ZZ male/ZW female system of genotypic sex determination has been postulated. Moreover, gonad differentiation is dependent on temperature and sex-reversed individuals can occur. To evaluate the importance of sex reversal among adult females, the blood of 78 animals was typed for the serologically detectable H-Y antigen, used as a tool to identify sexual genotype. In 73 of them, the H-Y phenotype was positive, conforming with female genotype, but in the other 5 females, it was negative (as in genotypic males), revealing that the sexual phenotype of these animals had been inverted. As the percentage of these sex-reversed genotypic males is low, the influence of temperature would appear not to be the sole cause of the observed unbalanced sex ratio. The female bias can be partly explained by the interaction of temperature with the ZZ/ZW system of genotypic sex determination. Indeed, in this system, sexual inversion under the influence of an epigenetic factor increases the ratio of genotypic females (ZW and WW) in the progeny.
A structural comparison of fault bars with feather defects known to be nutritionally induced
Authors: Murphy Mary E. , Miller Brian T. , King James R.
Published: March 2009

Fault bars are narrow, translucent bands in feathers where barbs lack barbules. It has been widely assumed that fault bars result from malnutrition and are therefore a record of the bird's nutritional status while growing or molting. We compared the microstructure of fault bars with that of defects correlated with experimental malnutrition (sulfur amino acid deficiency or deficiency of a balanced diet) in White-crowned Sparrows (Zonotrichia leucophrys gambelii). The structural defects in fault bars (mainly missing barbules) are unlike defects that accompany frank malnutrition (all structures present, but barbules too short or weak to interlock). We also subjected White-crowned Sparrows to 36 h of total fasting (12 to 19% loss of body mass). Fault bars or spots occurred in the rectrices of 19 of 44 starved birds. Some bars coincided with days on which birds were handled (19 of a total of 41 bars), others (22) occurred erratically in relation to handling or starvation days, but none coincided with starvation days. From these data and a review of previous investigations we conclude that there is little support for the notion that malnutrition always causes fault bars. Many kinds of stimuli are associated with fault bars. We suggest that the peripheral barbule cells are damaged by contractions of feather muscles that squeeze or crimp the soft feather sheath. Fault bars are not a reliable index of a bird's nutritional status while it is growing or molting.
Mitochondrial DNA patterns among endemic stickleback from the Queen Charlotte Islands: a preliminary survey
Authors: Gach M. H. , Reimchen T. E.
Published: March 2009

Mitochondrial DNA (mtDNA) restriction fragments were analyzed in 30 individuals from four populations of Gasterosteus aculeatus from the Queen Charlotte Islands, British Columbia. Two morphologically divergent endemic freshwater populations (Boulton Lake, Drizzle Lake), a typical stream form, and a brackish form were sampled. mtDNA size variation of 70 to 180 base pairs was noted among individuals from all populations, and 1.1 and 5.0 kilobase duplications were observed in mtDNAs from two individuals. Analysis of 75 mtDNA fragments produced by five restriction endonucleases revealed seven clones differing by less than 1.0% sequence divergence. While the high degree of genetic similarity is consistent with a postglacial origin of these populations, the presence of a unique restriction site among geographically isolated populations suggests that these endemics may have had a common freshwater ancestor that inhabited periglacial freshwater habitats rather than being independently derived from marine forms.
Ultrastructural study of the embryonic and larval shell of Anodonta cygnea
Authors: Castilho F. , Machado J. , Reis M. L. , Sá C.
Published: March 2009

An ultrastructural study of the embryonic and larval shell of Anodonta cygnea was carried out by light, polarization, and scanning electron microscopy, and X-ray diffraction analysis. A thin outer layer (cuticle), composed of β-keratin fibrils organized in parallel rows and enveloped by chitin material, was observed. The hooks, spines, and teeth are constituted by cuticular formations only. A calcareous inner layer presenting convergent prismatic monocrystals mainly of aragonite, which form prismatic structures around the pores and inside of irregular polygonal border lines, was also shown. Two clearly differentiated calcareous valves were already observed on very young embryos. The valvular pores totally covered by the cuticle may be involved in the metabolic cell exchange by penetrating cytoplasmatic extensions of the mantle cells. The irregular polygonal configuration observed on the internal surface of young decalcified cuticles supports the hypothesis of a role for the matrix as a regulator of shell formation, inducing the prismatic organization of the calcareous layer. Shell mineralization from the border lines to the center of each polygonal area may occur.
Structure, function, and development of setae on gill-grooming appendages and associated mouthparts of pinnotherid crabs (Decapoda: Brachyura)
Authors: Pohle Gerhard
Published: March 2009

Gills of pinnotherid crabs are groomed by setose epipodite extensions of maxilliped mouthparts. Unlike other Brachyura, some pinnotherid genera lack epipodites on maxilliped 2. Plumodenticulate setae similar to those found in other Crustacea represent the majority of grooming setae found on maxillipeds, maxillae, and maxillules in pinnotherids. Structurally more complex setae with anchor-shaped outgrowths were found in 7 of 19 investigated genera. Plumodenticulate setae with anchors are located on maxillules, maxillae, and maxilliped 1 epipodites of Opisthopus and Dissodactylus, whereas Pinnaxodes and Pinnotherelia carry them also on maxilliped 2 and 3 epipodites. In Anomalifrons and Xenophthalmus, some plumodenticulate setae on maxilliped 3 epipodites are armed with facing unequal recurved hooks, resembling ship chocks, in addition to anchors. Only one pair of chocks occurs per seta. Plumodenticulate grooming setae with long double prongs were found exclusively on four different mouthparts in Mortensenella. Larvae and early postlarval instars of Dissodactylus have a particular type of plumodenticulate grooming seta. These setae cover most of maxilliped 1 epipodite and the distal part of maxilliped 3 epipodite and are clustered on the anteroventral surface of maxillules and medially on maxillae. Some of these plumodenticulate setae develop anchorlike outgrowths between setules and denticules in larger crabs. Anchors appear about 2 months after hatching as a single pair per seta, with more pairs being added proximally to the first pair during consecutive stages. On maxillules, anchor setae become twice as numerous as plumodenticulate setae. On maxilliped 1 epipodites, proportions remain about constant. All anchor setae grow at about the same rate as the appendage on which they originate. Anchor setae on maxilliped 1 epipodites of the largest adult crabs may be over 2 mm long and with up to nine pairs of anchors, whereas those on maxillules are less than 1 mm long, bearing no more than six pairs of anchors. On maxillules, setae with two pairs of anchors remain the most common. On maxilliped 1 epipodites, the most common anchor seta for almost every third instar carries an additional pair of anchors, starting with one pair in instar 6 to seven pairs in instar 27. Anchor setae are also found proximally on the protopodite of maxillae in the smallest juvenile crabs but do not develop anchors until close to maturity. On average, each maxilla carries one anchor seta equipped with a single pair of anchors. Anchor setae were not found on any other appendages or cuticular surfaces. Grooming setae seem to lack chemosensory characteristics. Plumose and denticular outgrowths are interpreted as brushing and combing devices. Anchors, chocks, and double prongs seem particularly suited for dislodging of larger objects or organisms, introduced as larvae by the respiratory current, and also might aid in stripping other plumodenticulate setae of accumulated debris.
Experimental investigations of the evolutionary significance of sexually dimorphic nuptial colouration in Gasterosteus aculeatus (L.): temporal changes in the structure of the male mosaic signal
Authors: McLennan D. A. , McPhail J. D.
Published: March 2009

Although classically described as "red," the three-spined stickleback male's nuptial signal is a complex mosaic of at least three colours: blue eyes, black dorsal–lateral body, and red ventral–lateral body. Seven variables (intensity, hue, and distribution of red body colour; intensity and hue of blue eye colour; intensity and distribution of black body colour) were scored for 19 males across an entire breeding cycle. These variables interacted to produce four distinct male colour mosaic signals corresponding with the stage a male had reached in the breeding cycle. No single variable was sufficient for the delineation of all breeding stages: however, the distribution of red body colour reliably distinguished the courting male from nesting and parental males. Variability in signal intensity between courting males was greatest for the red component of the nuptial signal and both intra- and inter-male variability in the overall intensity of red was greatest during courtship. Based upon these results, future investigations of the role of intersexual selection in shaping the male nuptial signal in this species should offer females a choice between males differing in the intensity of red rather than the traditional "red" versus "nonred" dichotomy.
Experimental investigations of the evolutionary significance of sexually dimorphic nuptial colouration in Gasterosteus aculeatus (L.): the relationship between male colour and male behaviour
Authors: McLennan D. A. , McPhail J. D.
Published: March 2009

The intensities of red body and blue eye colour in dull (and possibly bright) males reliably signals their behavioural vigour. Males with medium intensity colouration signal that they are more vigorous than their dull conspecifics; however, there is no association between colour and behavioural intensity within this group. A truth in advertising mechanism is thus potentially very powerful at either end of the colour intensity spectrum but is less effective for fish whose colouration is in the central section of the spectrum. Males with medium intensity colouration may be more strongly influenced by stochastic factors such as previous experiences or colour relative to neighbours. The increased importance of personal history introduces a source of disorganization into the mating system that may oppose the directional force of truth in advertising and thereby increase the ambiguity of the male colour signal.
Factors affecting surfacing, respiration, and dive behaviour of bowhead whales, Balaena mysticetus, summering in the Beaufort Sea
Authors: Dorsey Eleanor M. , Richardson W. John , Würsig Bernd
Published: March 2009

Behaviour of bowhead whales summering in the Canadian Beaufort Sea in 1980–1984 was observed from an aeroplane circling at altitudes high enough to avoid disturbance (≥ 457 m). Factors that might affect surfacing and respiration behaviour were assessed with univariate and multivariate analyses. Calves (age < 1 year) were not considered. The interval between successive blows in a surfacing was more stable over time and over different activities than were the other variables but was significantly longer in surface-feeding whales. Surface feeders also made longer surfacings. The number of blows per surfacing and duration of surfacing were highly correlated, and both variables were more consistently correlated with the duration of the previous dive than with the duration of the subsequent dive. There were considerable interyear variations in respiration and surfacing characteristics that could not be attributed to any measured factor. Effects of water depth on number of blows per surfacing could not be separated from interyear effects, but duration of surfacing appeared to be greater in deeper water. Whales in groups had longer blow intervals, as did mothers with calves and socializing whales. Underwater blows were associated with socializing, at least at times, but their function is uncertain. The results have implications with regard to bowhead energetics, sightability during aerial surveys, and interpretation of behaviour in the presence of human disturbance.
Dynamics of a grizzly bear population during a period of industrial resource extraction. II. Mortality rates and causes of death
Authors: McLellan Bruce N.
Published: March 2009

The causes and rates of grizzly bear (Ursus arctos) mortality in a radio-marked population in southeastern British Columbia were studied for 9 years during a period of timber harvest, gas exploration, and outdoor recreation, including grizzly hunting. During 110 bear-years of radio tracking 55 radio-collared grizzly bears and their dependent offspring, one bear with a functioning radio collar died from natural causes and eight others from human intervention; in addition, four dependent offspring were thought to have died. Excluding trap-related mortalities, the best estimate for the annual survival rates were as follows: 0.82 for cubs, 0.88 for yearlings, 0.93 for subadults, and 0.93 for adults. Of the eight bears killed by human intervention, two were killed by legal harvest, five by illegal harvest (one of these in a trap), and one was killed in a trap by another bear. No mortalities were directly attributable to industrial activities. Resource extraction industries do contribute to grizzly bear mortality indirectly through the construction of roads, which provide easy access to hunters, poachers, and settlers. Road access planning and postoperational control of vehicles are recommended management actions.
Sexual differences in the annual lipid cycle of the big brown bat Eptesicus fuscus
Authors: Pistole David H.
Published: March 2009

The annual lipid cycle in male and female big brown bats, Eptesicus fuscus, was studied in relation to the reproductive patterns for each sex. The basic pattern of lipid deposition and use was similar in males and females; however, there were differences between the sexes in the timing of these activities. Females began rapid fat deposition 1 month earlier than males. The beginning of rapid fat deposition in females is associated with the end of lactation and in males with the end of spermatogenesis and the peak mating season. Rates of fat use were similar between the sexes for the entire hibernation period, but the rate in females was more consistent than the rate in males. The caloric content of male bats did not differ throughout the year, but females had higher values during pregnancy and lactation than at other times of the year. Differences between the sexes in the timing of specific events within the annual lipid cycle appear to be adaptations for optimizing reproductive success.
Radula-tooth biometry in Helisoma trivolvis (Gastropoda, Pulmonata): interpopulation variation and the question of adaptive significance
Authors: Smith David A.
Published: March 2009

A statistically significant biometric variation was identified among 1890 radula teeth sampled from Helisoma trivolvis (Say) taken from 21 sites in central New York State, U.S.A. For two shape-defining variables, 39 and 42% of all pairwise comparisons between population means were significantly different at P < 0.05. Twenty-two and 24% of these comparisons were still significantly different at P < 0.00001. Five intensively studied sites differed with regard to Aufwuchs biomass, Aufwuchs productivity, and diatom community composition. There were few statistically significant associations between radula-tooth shape and these parameters. Two hypotheses regarding the nature of tooth-shape variation in these gastropod populations were evaluated.
Nocturnally constrained foraging of a lotic minnow (Rhinichthys cataractae)
Authors: Culp Joseph M.
Published: March 2009

Diel periodicity in foraging activity of the longnose dace (Rhinichthys cataractae) was determined by measuring dace activity over the stream bed, gut fullness, and the digestive state of prey items. Although most species of minnows are either diurnally or crepuscularly active, dace began foraging within 1 h after sunset with light levels near 10 lx and ceased before sunrise throughout the ice-free period. During the day few prey were taken as the dace remained under the shelter of stones. This nocturnal foraging pattern did not appear to be affected by spawning or seasonal changes in prey composition. Nocturnal foraging in dace is not likely a response to prey availability, but may be a response to avoid diel periods when salmonid competitors or visual predators are active.
Littoral feeding in a high-density insular population of Sorex cinereus
Authors: Stewart D. T. , Herman T. B. , Teferi T.
Published: March 2009

In a high-density insular population of masked shrews (Sorex cinereus), Diptera, amphipods, Araneae, and Coleoptera dominated the diet. The prominence of littoral amphipods and kelp flies in the diet indicates a pattern of beach foraging not previously described for this shrew. Remains of these prey were found in shrews captured as far as 60 m inland. We speculate that abundant littoral invertebrate prey, present throughout much of the year, partly sustain the high number and extended breeding season of shrews on this island.
The 1982–1983 El Niño event recorded in dentinal growth layers in teeth of Peruvian dusky dolphins (Lagenorhynchus obscurus)
Authors: Manzanilla Silvia R.
Published: March 2009

Dusky dolphins (Lagenorhynchus obscurus) recorded the effects of the 1982–1983 El Niño event in the form of anomalous dentine deposited during 1983. This anomaly, which I call the El Niño mark (ENM), consists of a pair of hypocalcified incremental layers about 75 μm in width, located within the 1983 growth layer group. The anomaly was present in 15 of 18 mature females, 1 of 9 immature females, and only 1 of 14 mature and immature males. Teeth from other species inhabiting the upwelling system were examined and revealed no ENM. Dusky dolphins feed primarily on anchoveta (Engraulis ringens), the stocks of which collapsed during the 1983 El Niño; this collapse severely affected other anchoveta predators. It is possible that the ENM reflects the presumably low foraging success experienced by dusky dolphins in 1983. However, it is unclear why the ENM is present in most mature females and absent from most male specimens. The discovery of the El Niño mark in dusky dolphins provides the first convincing evidence in odontocete cetaceans of a direct environmental influence on the mineral quality of dentine deposited during a period of markedly abnormal climatic conditions.
Acquisition de cnidocystes et différenciation de pseudocolloblastes chez les larves et les adultes de deux cténophores du genre Haeckelia Carus, 1863
Authors: Carré Danièle , Carré Claude
Published: March 2009

The development of two species of cydippid Ctenophora, Haeckelia rubra and Haeckelia bimaculata, was studied to determine the origin and acquisition of exogenous cnidocysts in these two species, which lack colloblasts. A new type of cell, the pseudocolloblasts, is described. In H. rubra, the outer layer of the egg contains cnidocysts which are ingested by the larva after gastrulation; these cnidocysts make up the initial stock of exogenous cnidocysts that will allow the ctenophore to catch its first Cnidaria. In H. bimaculata, the outer layer of the egg is devoid of cnidocysts. The hatching larva has no cnidocysts either, but its tentacles are lined by an hitherto unknown type of glandular cell that we have named the pseudocolloblast. Pseudocolloblasts are composed of a secretory head bearing regularly interspaced, striated structures and an anchoring stalk. They eject their content progressively during successive phases of exocytosis. Pseudocolloblasts differ morphologically from real colloblasts, but they probably have the same function and they allow larvae of H. bimaculata to catch cnidarian larvae and thus acquire the exogenous cnidocysts present in postlarval and adult stages. Cnidocysts are identical in both species of Haeckelia in the Mediterranean Sea, consisting of macroisorhizas and microisorhizas in which the intracapsular filament has five circumferential pleats, a character typical of Narcomedusae. They differ in size from the cnidocysts found in H. rubra in the Pacific and in the Sea of Japan.[Journal translation]
Foraging behaviour of oystercatchers Haematopus ostralegus during a diet switch from worms Nereis diversicolor to clams Scrobicularia plana
Authors: Boates J. Sherman , Goss-Custard John D.
Published: March 2009

On the mudflats of the Exe Estuary in southwest England, oystercatchers Haematopus ostralegus switched from eating worms Nereis diversicolor to clams Scrobicularia plana during autumn. A decline in the profitability of worms (from 17 to 4 mg/s handling time) and the food intake of oystercatchers eating worms (from 1300 to < 200 mg/15 min) occurred prior to and during the switch to clams. Declines in profitability and food intake rate were due to seasonal changes in the size and food value of worms available to oystercatchers. Capture rate on worms varied little prior to, or during, the switch. Oystercatchers appeared to switch diets in response to changes in the reward offered by worms rather than in response to relative changes in the reward offered by the two prey species. This is because individual oystercatchers were never observed eating a mixed diet of worms and clams, and may explain why it took 6 weeks (11 October to 25 November) for the population to complete the switch.
Determinants of nest success in the marbled salamander (Ambystoma opacum)
Authors: Jackson Mary E. , Scott David E. , Estes Ruth A.
Published: March 2009

Nest distribution and nest success (i.e., the proportion of a clutch that successfully hatched to the free-swimming larval stage) of the terrestrial-breeding marbled salamander, Ambystoma opacum, was examined at a breeding site in South Carolina, U.S.A. Females placed nests in areas of high total vegetative cover, and tended to concentrate nests in the lowest portion of the breeding site. Nests placed at high and medium elevations exhibited a nonrandom aggregated pattern, whereas nests at low elevations were randomly distributed. Nest success of 85 nests was highest at low elevations, and was positively correlated with the number of days a female remained with (brooded) the nest. Natural selection may favor nest site selection and nest brooding behavior as mechanisms to reduce embryonic mortality.
Ectoparasitism of nestling House Wrens, Troglodytes aedon, by larvae of the blow fly Protocalliphora braueri (Diptera: Calliphoridae)
Authors: Eastman Marjorie D. , Johnson L. Scott , Kermott L. Henry
Published: March 2009

We provide the first detailed information concerning ectoparasitism of nestling birds by larvae of the blow fly, Protocalliphora braueri Hendel. This species is unusual among Protocalliphora because its larvae cause a subcutaneous myiasis in small birds. We examined the pattern of infestation, and the effect of parasites on nestling survival and body size at fledging in a population of House Wrens, Troglodytes aedon. Twenty-five of 71 nests (35%) in the population were infested. Infested nestlings hosted an average of five larvae each. Myiases occurred in virtually all parts of nestling bodies, and larvae were visible on hosts for approximately 3 days. Parasitism did not appear to affect nestling survival if larvae appeared after the nestlings were approximately 6 days old. Some young infested at ages younger than this appeared to die as a result of parasitism, but infestation at these ages was rare (only 12% of nests). Comparison with other studies of dipteran ectoparasitism suggests that in most cases, parasite loads in our population are generally too low to have any significant effect on nestling survival. We also found no relationship between the intensity of parasitism and the tarsus size of nestlings at the time that they fledge, as measured by tarsus length.
Salinity tolerance of larval and juvenile broad whitefish (Coregonus nasus)
Authors: March B. G. E. de
Published: March 2009

In the absence of distribution data for juvenile broad whitefish, Coregonus nasus, laboratory experiments were designed to elucidate the salinity ranges that the species will tolerate. Larval fish (12–18 mm) died within 120 h at salinities of 12.5‰ and higher at both 5 and 10 °C, though more slowly at 5 °C. Salinities of 12.5 and 15‰, but no higher, were tolerated for 120 h at 15 °C. Larvae fed readily at 15 °C but not at 5 or 10 °C. Slightly larger and more-developed larvae (15–19 mm) were tolerant of 12.5‰ but died within 120 h at 15‰ at the same three temperatures. These fish fed more readily than the younger ones. Larger fish (33–68 mm) were generally tolerant of 15–20‰ but not of higher salinities in 120-h tolerance tests. Larger field-collected fish (27–200 mm) reacted similarly but were more tolerant of salinities between 20 and 27‰ in 96-h tests. Analysis of both experiments with larger fish suggests that time to death was inversely related to size as well as to salinity. Coregonus nasus does not seem to be more tolerant of saline conditions than other freshwater or migratory fish species. Experimental results combined with limited information about the species' distribution suggest that man-made constructions on the arctic coast might seriously affect dispersal or annual migrations.
A new species of Priolepis (Pisces: Gobiidae) from the Pacific plate, with biogeographic comments
Authors: Winterbottom Richard , Burridge Mary
Published: March 2009

The diagnosis of Priolepis is refined by the autapomorphic presence of two rows of denticles or odontoids on the medial surfaces of the lateral gill rakers of ceratobranchial 1. Priolepis squamogena n.sp. is described on the basis of specimens from the Society, Tuamotu, Southern Line, and Marquesas islands in the South Pacific. Specimens of what may be this species are reported from the northern Line Islands and from How land Island. The new species may be distinguished from its apparent sister species, Priolepis cincta (Indo-west Pacific and marginally on the Pacific plate), by the presence of cheek scales, and from Priolepis eugenius (Hawaii) in lacking a well-developed interorbital–postorbital trench.
A revision of the Trimmatom nanus species complex (Pisces, Gobiidae), with descriptions of three new species and redefinition of Trimmatom
Authors: Winterbottom Richard
Published: March 2009

Trimmatom is rediagnosed to include gobiids in which the first element of the anal fin is a bilaterally paired ray, the fifth pelvic ray is unbranched and reduced to 15% or less of the length of the fourth, the head, pectoral-fin base, and breast are scaleless, there are no head pores, and the gill opening extends anteroventrally at least to below the vertical limb of the preopercle. The Trimmatom nanus species complex is considered to be monophyletic by virtue of an unbranched fourth pelvic-fin ray. Trimmatom macropodus, n.sp., recorded from Taiwan, the Philippines, the Coral Sea, and the Great Barrier Reef, has a scaled body and the first three pelvic-fin rays are branched. Trimmatom zapotes, n.sp., from the Caroline and Gilbert islands and Great Barrier Reef, has a scaled body and all pelvic-fin rays are unbranched. Among the three scaleless species, Trimmatom offucius is restricted to the Chagos Archipelago and has two dark saddles crossing the bases of fin rays in the second dorsal fin. Trimmatom sagma, n.sp., from the Cocos-Keeling Islands, the Philippines, and the Moluccas, has a single dark saddle across the base of the second dorsal fin and a unique dorsal pterygiophore formula. Trimmatom nanus lacks dark saddles over the dorsum. The known geographic range of this species is greatly expanded, from the type locality in the Chagos Archipelago to include the Philippines, Papua New Guinea, the Caroline Islands, the Gilbert Islands, Fiji south to South Minerva Reef, Lord Howe Rise, the Coral Sea, western Australia, and the Maldives.
Effects of humidity, temperature, and submergence behavior on survivorship and energy use in hibernating garter snakes, Thamnophis sirtalis
Authors: Costanzo Jon P.
Published: March 2009

Desiccation is likely an important factor influencing winter mortality rates of terrestrially hibernating reptiles; however, this notion has not been rigorously tested. Groups of eastern garter snakes (Thamnophis sirtalis sirtalis) were matched for size and subsequently exposed to simulated hibernative conditions (5 or 12 °C, under different humidity regimes) during winter, for 165 days or until all group members expired. As garter snakes in some dens submerge during natural hibernation, an additional group was maintained in water at 5 °C. Snakes kept in air dehydrated and died (body water contents at death ranged from 62.1 to 67.8% of lean fresh mass), whereas snakes kept in water remained hydrated (median, 75.2%) and survived. Survival duration of air hibernators was inversely related to rate of mass loss, which in turn was strongly influenced by ambient humidity and temperature. Dehydration accounted for most of the mass lost in all air hibernators; however, owing to higher rates of nutrient consumption, mass loss was significantly greater in snakes kept at 12 °C (36%) than in snakes kept at 5 °C (29%). Changes in fat body and liver masses showed that snakes kept in air at 12 °C used the most energy whereas those kept in water at 5 °C used the least. Submerged hibernation behavior has significant survival value because under these conditions snakes remain hydrated during winter. Also, because submerged snakes conserve more stored energy during winter, their reproductive success may be enhanced when mating activities resume in early spring.
Prolonged, continuous, deep diving by northern elephant seals
Authors: Boeuf Burney J. Le , Naito Yasuhiko , Huntley Anthony C. , Asaga Tomohiro
Published: March 2009

An earlier study showed that female northern elephant seals (Mirounga angustirostris) dive deeply and continuously during the first 1–3 weeks at sea following lactation. We report that this dive pattern is maintained for the entire 2½-month period at sea. Time–depth recorders were attached to six adult females at Año Nuevo, California; three instruments recorded continuously and three instruments recorded every 3rd day at sea. The mean dive rate was 2.5–3.3 dives per hour, with a mean of < 3.5 min on the surface between dives. This resulted in females spending 83–90% of the time at sea underwater. Interruption of continuous diving, characterized by extended surface intervals with a mean of 51.9 ± 65.5 min, was rare, following only 0.42% of the dives. Modal dive duration per female was in the range 17.1–22.5 min. The longest dive was 62 min and was followed by a surface interval of < 2.6 min. Modal dive depth per female was in the range 500–700 m; three females had dives that exceeded 1000 m, with the deepest dive estimated at 1250 m. Deep diving to 500 m or more was always preceded by a descending-staircase pattern of initially shallow to increasingly deeper dives. The continuous, deep diving pattern of this pelagic seal is evidently a steady-state condition. This has important implications for understanding diving adaptations and the physiological processes underlying them.
Nightly and hourly rates of attraction of flying field crickets, Gryllus integer, to conspecific song
Authors: Cade William H.
Published: March 2009

Nightly and hourly rates of attraction of flying field crickets, Gryllus integer, to conspecific calling song were studied in an arena placed in the natural habitat of the species in central Texas. Calling of male G. integer in the arena and tape-recorded broadcasts of conspecific song were the sources of cricket song that subsequently attracted flying crickets. Observations were conducted for 10 h from approximately 1.5–2 h past sunset to 3 h past sunrise for 97 nights in 1983 and 1985–1988, using calling males, and for 4 nights in 1988, using taped song. The number of crickets attracted each night varied greatly, significantly more females were attracted, the numbers of males and females attracted decreased near sunrise, and significantly more crickets entered the arena from 2 to 6 h than from 7 to 11 h past sunset. Results are discussed in the context of mating behavior and sexual selection in this and other species.
Phenotypic correlates of mating success in the sand wasp Bembecinus quinquespinosus (Hymenoptera: Sphecidae)
Authors: O'Neill Kevin M. , Evans Howard E. , O'Neill Ruth P.
Published: March 2009

Females of the sand wasp Bembecinus quinquespinosus nest in dense aggregations, the offspring emerging in great numbers the following year. Males display alternative mating tactics. Large males search and dig for females about to emerge from the ground. Mating success here is correlated with body size, primarily because larger males are better able to carry the female in flight away from the emergence area and avoid further harassment. The largest males, representing about one-quarter of the population, obtained over 90% of the matings initiated in the emergence area, whereas males below average in size were never successful there. Because some females leave the area without mating, a pool of virgins is available to small males, who patrol just outside the emergence area and intercept passing females. Males below average in size (and all females) are black with pale white bands on the abdomen. In males above mean size, the proportion of yellow pigmentation on the dorsal and lateral surfaces increases with body size. Males undertaking alternative tactics experience differing thermal environments. Yellow colouration was correlated with higher cuticular reflectance. Comparative evidence and differences in the activity patterns of males of different colour suggest that yellow pigmentation acts as a thermoregulatory mechanism allowing larger males to increase their tolerance of the high temperatures and solar radiation loads in the emergence area. We hypothesize that the mating tactics represent condition-dependent behavioural tactics, with flexibility maintained by sexual selection, and that the colour patterns represent condition-dependent morphological tactics, with the developmental response favoured by selection for thermoregulatory ability.
The haemoproteids of the avian order Strigiformes
Authors: Bishop Madonna A. , Bennett Gordon F.
Published: March 2009

The avian order Strigiformes consists of two families, the Strigidae (136 species) and the Tytonidae (12 species). To date 13 species of haemoproteids (Haemosporina: Haemoproteidae) have been described from the Strigidae, whereas none has been described from the Tytonidae. Haemoproteus asio and H. otus are nomina nuda. Haemoproteus bubonis, H. aluci, and H. glaucidiumi are designated nomina dubia. Haemoproteus glaucidii partim, H. bramae, H. cellii partim, and H. nebraskensis are synonymized with H. noctuae. Haemoproteus glaucidii partim, H. cellii partim, H. multiparasitans, and H. aegyptius are synonymized with H. syrnii. Haemoproteus noctuae and H. syrnii are redescribed and neohapantotypes and paranaeohapantotypes are designated. Haemoproteus phodili n.sp. and Haemoproteus tytoni n.sp. are described from the Tytonidae.
Cortisol-induced changes in plasma glucose, protein, and thyroid hormone levels, and liver glycogen content of coho salmon (Oncorhynchus kisutch Walbaum)
Authors: Vijayan M. M. , Leatherland J. F.
Published: March 2009

Coho salmon given intraperitoneal implants of hydrogenated coconut oil alone or coconut oil containing cortisol at 1, 5, or 10 mg/fish exhibited dose-related increases in plasma cortisol levels at day 15. After 30 days, plasma cortisol levels were significantly higher in the cortisol-implanted groups but there was no dose-related response. Plasma T3 levels were lowered in cortisol-treated fish, but plasma T4 levels were not consistently affected. Plasma glucose levels were significantly higher in the group treated with cortisol at 10 mg/fish than in the controls on both sampling days, whereas liver glycogen content and hepatosomatic index were significantly lower in the cortisol-treated groups at day 30 but not at day 15. Plasma protein levels were not significantly different between treatments at either sampling time. The splenosomatic indices were not significantly different in the three treatment groups at day 15, but at day 30 the values in the 5 and 10 mg/fish cortisol-treated groups were significantly higher than in the controls.
Age-class influences on feeding choices of free-ranging wild boars (Sus scrofa)
Authors: Dardaillon Maryse
Published: March 2009

Diet composition and diversity were compared between juvenile, yearling, and adult wild boars living in the Camargue region (southern France). Despite close similarity, feeding choices differed in various respects. First, the mean stomach content included a greater proportion of animal matter in subadults (juveniles and yearlings combined) than in adults. Secondly, yearlings and adults ate larger proportions of rice, and larger quantities by weight of underground plant parts, than juveniles. These differences were attributed to differing nutritional requirements according to age-class. On the other hand, greater diversity of feeding choices was found in juveniles than within the yearling and adult age-classes. It is argued that early experience of a broad dietary diversity is an advantage for coping with fluctuations in food availability such as those encountered in the Camargue.
Life history and behavior of mites in the genus Lasioseius (Acari: Mesostigmata: Ascidae) from grassland soils in Colorado, with taxonomic notes and description of a new species
Authors: Walter David Evans , Lindquist Evert E.
Published: March 2009

Lasioseius berlesei (Oudemans), Lasioseius youcefi Athias-Henriot, Lasioseius kinikinik n.sp., and Lasioseius confusus Evans were collected from grassland soils in Colorado. Lasioseius berlesei and L. youcefi are known only from the female, and for the first time in an ascid mite, we experimentally demonstrate that they reproduce by thelytokous parthenogenesis. Both species are omnivores that will feed on fungi and animal prey, and they share a multidenticulate ridge apposed to a groove on the paraxial faces of the chelicerae which appears to function as a mashing and filtering mechanism during mycophagy. Similar cheliceral structures are lacking in L. kinikinik n.sp. (described in this paper), a bisexual species that must mate to produce eggs, and does not feed on fungi. Diagnoses are presented for L. berlesei, L. youcefi, and L. confusus, and their sperm reception structures (spermatheca, etc.) are illustrated for the first time. Based on the study of type specimens, new morphological evidence, and rearings, we propose that (i) the previous synonymy of L. confusus with L. berlesei be rejected; (ii) Lasioseius mcgregori Chant, 1963 is a junior synonym of L. youcefi Athias-Henriot, 1959; (iii) L. scapulatus Kennett, 1958 is a junior synonym of L. dentatus (Fox, 1946); and (iv) L. furcisetus Athias-Henriot, 1959 is the correct name for L. penicilliger sensu Evans, 1958 and subsequent authors, not Berlese, 1916; L. lanciolatus Chant, 1963 is a junior synonym of L. furcisetus.
Occurrence of threespine sticklebacks (Gasterosteus aculeatus) in the open North Pacific Ocean: migration or drift?
Authors: Quinn T. P. , Light J. T.
Published: March 2009

This paper documents the occurrence of a small fish species, the threespine stickleback (Gasterosteus aculeatus), in the open North Pacific Ocean. Sticklebacks were incidentally caught in 77 of 4138 (1.86%) purse seine sets for Pacific salmon and were found in the stomachs of 31 of 639 (4.85%) steelhead trout (Salmo gairdneri) caught on the high seas. If destined to reproduce, these pelagic sticklebacks would be an exception to the general rule that long distance migration is undertaken only by large fish species, but it is also possible that they were isolated from breeding populations.
The occurrence of Diplostomum spathaceum metacercariae in the freshwater drum, Aplodinotus grunniens
Authors: Leno Gregory H. , Holloway Jr. Harry L.
Published: March 2009

Strigeoid metacercariae from the lenses of freshwater drum, Aplodinotus grunniens, were morphometrically analyzed and compared with those of the North American subspecies of Diplostomum spathaceum: Diplostomum spathaceum indistinctum and Diplostomum spathaceum huronense. The metacercariae resembled D. s. indistinctum in mean body length, mean body width, oral sucker size, and holdfast size. Prevalence of infection in drum was 99% and intensity ranged from 0 to 260 worms per fish (mean ± SD = 35 ± 32). A significant difference (P < 0.05) in mean intensity between male and female fish was observed, with females harboring a greater worm burden (i.e., 43 in females versus 24 in males). Differences in infection intensity between left and right lenses from all fish were not significant (P > 0.05); however, the degree of asymmetry between left and right lenses of individual fish was highly significant (P < 0.005) according to heterogeneity χ2 analysis. In this case, neither left nor right lenses were consistently favored.
STUDY ON SOFTENING CONSTITUTIVE MODEL OF SOFT ROCK USING STRAIN SPACE BASED UNIFIED STRENGTH THEORY
Authors: SONG LI , CHO CHONGDU , LU SHENG , LIAO HONGJIAN
Published: March 2009

This study attempts to modify the unified strength theory by considering compression as a positive load in geotechnical engineering. It also aims to establish a unified elastoplastic strain softening constitutive model which can accurately describe the strain softening behavior of one kind of soft rocks distributed in Japan. The hardening function parameters of the unified elastoplastic strain softening constitutive model are determined from experiments. In addition, numerical simulations of this model are performed to compare the pre-peak, post-peak and the residual strengths of soft rock predicted by this study and experimental results. Simulation results demonstrated that the proposed constitutive equations in strain space can well describe the softening behavior and accurately predict the peak and residual strengths of soft rock. While the proposed equation is applicative for normally consolidated state and overconsolidated state according to the simulation results.
ANALYSIS OF COLLISION BETWEEN DRILLSTRING AND WELL SIDEWALL
Authors: ZHAO G.H. , LIANG Z.
Published: March 2009

Drillstring is the most important tool in petroleum drilling engineering. Alternating stress has been found to be responsible for the premature failure of drillstring. Propagation of stress wave, induced by collision between tool-joints of drillstring and borehole wall, is studied in this paper. The condition that all the tool-joints of drill pipes (DPs) strike borehole wall at the same time has been considered. Because of symmetry, the middle cross section of the DP is simplified as fixed end, and mechanical model is established as the beam with both ends fixed. Propagation of lateral displacement wave and stress wave in the DP is investigated by means of Eigen-frequency method and the Finite Element Analysis software ANSYS. The theoretic results coincide with those obtained from numerical modeling very well and also explain the drillstring accidents in gas fields.
FE SIMULATION OF EDGE CRACK INITIATION AND PROPAGATION OF CONVENTIONAL GRAIN ORIENTATION ELECTRICAL STEEL
Authors: NA D. H. , LEE Y.
Published: March 2009

Three-dimensional finite element simulation has been carried out to understand better the crack initiation and growth at the edge side of silicon steel sheet during cold rolling, which is attributable to elastic deformation of work roll, i.e., roll bending. Strain-controlled failure model was coupled with finite element method and a series of FE simulation has been carried out while three different roll bending modes are considered. FE simulation shows that the negative roll bending mode during rolling affects significantly the crack initiation behavior. When the strain for failure was reduced by 20%, number of elements removed was increased by about 305%. If an initial crack with 2.5mm in length was assumed on the strip, the initial edge crack propagated toward inner region of strip and the propagated length is about 10times of the initial edge crack length.