Summer food habits of female new river crayfish (Cambarus chasmodactylus) in Anthony Creek, West Virginia

2015 ◽  
Vol 21 (1) ◽  
pp. 95-101
Author(s):  
Raquel A. Fagundo ◽  
Zachary J. Loughman
Keyword(s):  
Body Size ◽  
West Virginia ◽  
Food Habits ◽  
Linear Models ◽  
Late Summer ◽  
Reproductive State ◽  
Organic Detritus ◽  
Central Appalachians ◽  
Ecological Implications ◽  
Food Consumed

Abstract Cambarus chasmodactylus is restricted to the New River drainage of the Central Appalachians. Female crayfish display cyclic reproductive states, but the ecological implications of this cycle have yet to be assessed. Female C. chasmodactylus were collected from Anthony Creek, West Virginia during the summer months to investigate food habits. Stomach content frequencies were obtained for four broad categories. Food items were identified to the lowest taxonomic level applicable. Feeding spectra were used to assess the importance of prey items. Generalized linear models were used to assess the effects of season, body size, and reproductive state on broad food categories, amount of food consumed, and the frequency of the most abundant prey item. The most food was consumed during June and the least in August. Organic detritus was consumed most frequently and reached its highest frequency in late summer. Animal matter was consumed more frequently by larger animals. Snails were the most predominate animal ingested, showing lower frequencies in June and September in comparison to August and October. Results indicate New River crayfish are feeding generalists and food habits changed with season. There is indication that body size and reproductive state may have a direct or indirect link to food habits.

scholarly journals Longevity of Willow Tits (Poecile montanus): the significance of flock membership, social rank and body size

2018 ◽  
Vol 41 ◽  
pp. 13-18
Author(s):  
Olav Hogstad ◽  
Tore Slagsvold
Keyword(s):  
Body Size ◽  
Social Rank ◽  
Late Summer ◽  
High Rank ◽  
Subalpine Forest ◽  
Social Hierarchies ◽  
Willow Tit ◽  
Males And Females ◽  
Winter Flocks ◽  
Main Factor

The Willow Tit Poecile montanus is highly sedentary and breeding pairs remain in their exclusive areas throughout the year. During the winter, these areas are defended by small, non-kin flocks, formed as the roaming yearlings become sedentary and join adults during late summer and autumn. Once established, stable social hierarchies are maintained in these flocks during the winter. The winter flocks consist normally of the socially dominant adult mated pair and two mated juvenile pairs, one higher-ranked and one lower-ranked. Individually colour-ringed juvenile Willow Tits were followed over years in subalpine forest in Norway from ringing in the autumn till they disappeared. None of the lower ranked birds survived their first winter, whereas only 4 of 71 higher-ranked juvenile pairs disappeared during this time. Half of the 71 pairs survived their first winter, about 25 % survived two winters, 8.5% survived three winters, and 5.6% survived four winters. Survival was similar for males and females. Alpha pairs remained mated and defended their common territory across years. Maximum age as revealed by ringing showed one female became six years old and two males ringed as adults were at least nine years old when last observed. The main factor associated with survival was early flock establishment that led to a high rank position among the juvenile flock members. Body size seemed insignificant. Birds that survived their first winter either succeeded to establish as territory owners or they were forced into the role as floaters and probably perished.

Solar Ultraviolet Radiation Exposure among Outdoor Workers in Three Canadian Provinces

2019 ◽  
Vol 63 (6) ◽  
pp. 679-688 ◽  
Author(s):  
Cheryl E Peters ◽  
Elena Pasko ◽  
Peter Strahlendorf ◽  
Dorothy Linn Holness ◽  
Thomas Tenkate
Keyword(s):  
British Columbia ◽  
Ultraviolet Radiation ◽  
Linear Models ◽  
Late Summer ◽  
Solar Ultraviolet Radiation ◽  
Sun Safety ◽  
Outdoor Workers ◽  
Exposure Limit ◽  
Canadian Provinces ◽  
Solar Ultraviolet

AbstractIntroductionSolar ultraviolet radiation (UVR) exposure places outdoor workers at risk of skin cancer and exposure is difficult to control. In response, the Sun Safety at Work Canada (SSAWC) project was undertaken (2014–2016). The purpose of this substudy was to characterize the UVR exposure levels of outdoor workers in the SSAWC project.MethodsThirteen workplaces in the provinces of British Columbia, Ontario, and Nova Scotia participated in an exposure monitoring campaign (late summer/early fall 2016). Study participants were workers from power utilities and municipalities. Participants wore a UVR measurement badge (light-sensitive polysulfone plastic) on their wrist, shoulder, or hardhat. Badge calibration and absorbance measurements were performed in the AusSun Research Lab. Personal UVR doses are presented as standard erythemal doses (SED) and compared with the internationally recommended exposure limit (1.3 SED), as well as to the total available UVR by date. Generalized linear models were used to examine determinants of solar UVR for personal UVR dose (for both SED and percent of ambient UVR). Models considered badge placement, date, province, industry, main job task, and the hours spent outdoors.ResultsMean personal UVR dose of participating workers was 6.1 SED (nearly 5× the recommended limit). Just 14% of workers experienced ‘acceptable’ levels of solar radiation; 10% were exposed at >10 times the limit. In univariate analyses, workers in Ontario had the highest levels (mean 7.3 SED), but even in the lowest exposed province (British Columbia), the mean personal UVR dose was 4.5 SED. Utility workers had double the exposure of municipal workers (10.4 and 5.5 SED, respectively). In the determinants of exposure models, the differences by province were muted, but utility line workers and those in general maintenance had higher predicted exposures. Those who wore their badge on their hardhat also had higher values of SED in the fully adjusted determinants models.ConclusionsSolar ultraviolet overexposure among outdoor workers is a concern, even in a country like Canada with relatively low ambient UVR. Implementation of sun safety programs should be supported in an effort to reduce exposure in this vulnerable group of workers.

The Ecological Implications of Body Size.

1985 ◽  
Vol 22 (1) ◽  
pp. 291 ◽  
Author(s):  
N. Bonner ◽  
R. H. Peters
Keyword(s):  
Body Size ◽  
Ecological Implications

Allegheny Woodrat (Neotoma magister) Food Habits in the Central Appalachians

2002 ◽  
Vol 147 (1) ◽  
pp. 80-92 ◽  
Author(s):  
NIKOLE L. CASTLEBERRY ◽  
STEVEN B. CASTLEBERRY ◽  
W. MARK FORD ◽  
PETRA BOHALL WOOD ◽  
MICHAEL T. MENGAK
Keyword(s):  
Food Habits ◽  
Allegheny Woodrat ◽  
Neotoma Magister ◽  
Central Appalachians

CAUSES AND ECOLOGICAL IMPLICATIONS OF EGG RETENTION IN THE GYPSY MOTH, LYMANTRIA DISPAR (L.) (LEPIDOPTERA: LYMANTRIIDAE).

1987 ◽  
Vol 119 (9) ◽  
pp. 765-771 ◽  
Author(s):  
Pedro Barbosa ◽  
Peter Martinat
Keyword(s):  
Gypsy Moth ◽  
Lymantria Dispar ◽  
Egg Production ◽  
Pupal Development ◽  
Egg Retention ◽  
Gypsy Moths ◽  
Ecological Implications ◽  
Pupal Size ◽  
Food Consumed

AbstractThe role of starvation, the occurrence of mating, and delays and the onset of mating on the retention of eggs by the gypsy moth, Lymantria dispar (L.), were evaluated. The mating status of female gypsy moths did influence egg retention.Mating delays did not affect egg retention. Differences in the number of females retaining some eggs were found among females whose larvae had been reared on different host plants. The amount of food consumed had a significant effect on egg retention. Partial starvation had an impact on egg retention and on larval and pupal development, pupal size, and total egg production. The greater the starvation the greater the egg retention. The ecological implications of these results are discussed.

scholarly journals Latitudinal gradients in body size in marine tardigrades

2019 ◽  
Vol 188 (3) ◽  
pp. 820-838
Author(s):  
Paul J Bartels ◽  
Diego Fontaneto ◽  
Milena Roszkowska ◽  
Diane R Nelson ◽  
Łukasz Kaczmarek
Keyword(s):  
Species Richness ◽  
Body Size ◽  
Net Primary Productivity ◽  
Linear Models ◽  
Generalized Least Squares ◽  
Sampling Bias ◽  
Latitudinal Gradients ◽  
Biased Sampling ◽  
Sampling Effort ◽  
Latitudinal Pattern

Abstract Homeotherms and many poikilotherms display a positive relationship between body size and latitude, but this has rarely been investigated in microscopic animals. We analysed all published records of marine Tardigrada to address whether microscopic marine invertebrates have similar ecogeographical patterns to macroscopic animals. The data were analysed using spatially explicit generalized least squares models and linear models. We looked for latitudinal patterns in body size and species richness, testing for sampling bias and phylogenetic constraints. No latitudinal pattern was detected for species richness, and sampling bias was the strongest correlate of species richness. A hump-shaped increase in median body size with latitude was found, and the effect remained significant for the Northern Hemisphere but not for the Southern. The most significant effect supporting the latitudinal gradient was on minimum body size, with smaller species disappearing at higher latitudes. Our results suggest that biogeographical signals were observed for body size, albeit difficult to detect in poorly studied groups because of swamping from biased sampling effort and from low sample size. We did not find a significant correlation with the latitudinal pattern of body size and ecologically relevant net primary productivity.

scholarly journals Abiotic Factors Influencing Deer Browsing in West Virginia

2006 ◽  
Vol 23 (1) ◽  
pp. 20-26 ◽  
Author(s):  
Tyler A. Campbell ◽  
Benjamin R. Laseter ◽  
W. Mark Ford ◽  
Richard H. Odom ◽  
Karl V. Miller
Keyword(s):  
West Virginia ◽  
Abiotic Factors ◽  
Woody Species ◽  
Surface Shape ◽  
Relative Importance ◽  
Deer Browsing ◽  
Mature Forest ◽  
Central Appalachians ◽  
Factors Influencing ◽  
Forested Ecosystem

Abstract We present a comparison of woody browse availability and white-tailed deer (Odocoileus virginianus) use among clearcut interiors, skidder trail edges, and mature forest and an evaluation of the relative importance of aboitic factors in predicting browsing pressure within regenerating clearcuts in the central Appalachians of West Virginia. We sampled 810 1-m2 plots in or adjacent to nine regenerating clearcuts (8–19 ha) during the summer of 2001. Availability and use of woody browse did not differ between clearcut interior and skidder trail plots for any species observed. Plots in the adjacent mature forest had less woody browse availability and higher utilization. Overall use of available woody browse in clearcuts was >15%. Combining all woody species, elevation (wI = 0.618) and distance to mature forest (wI = 0.379) were more important than landform index, plot surface shape, aspect, and slope in predicting deer browsing pressure in regenerating clearcuts. We believe that without management activities aimed at reducing deer browsing, in many parts of this region the ability of forest managers to regenerate stands will be jeopardized and the forested ecosystem will be compromised.

Reproductive state and choline intake influence enrichment of plasma lysophosphatidylcholine-DHA: a post hoc analysis of a controlled feeding trial

2019 ◽  
Vol 122 (11) ◽  
pp. 1221-1229
Author(s):  
Kevin C. Klatt ◽  
Melissa Q. McDougall ◽  
Olga V. Malysheva ◽  
J. Thomas Brenna ◽  
Mark S. Roberson ◽  
...  
Keyword(s):  
Linear Models ◽  
Major Facilitator Superfamily ◽  
Reproductive State ◽  
Lactating Women ◽  
Phosphatidylcholine Biosynthesis ◽  
Pregnancy And Lactation ◽  
Choline Intake ◽  
Major Facilitator ◽  
Post Hoc ◽  
Dietary Choline

AbstractThe major facilitator superfamily domain 2a protein was identified recently as a lysophosphatidylcholine (LPC) symporter with high affinity for LPC species enriched with DHA (LPC-DHA). To test the hypothesis that reproductive state and choline intake influence plasma LPC-DHA, we performed a post hoc analysis of samples available through 10 weeks of a previously conducted feeding study, which provided two doses of choline (480 and 930 mg/d) to non-pregnant (n 21), third-trimester pregnant (n 26), and lactating (n 24) women; all participants consumed 200 mg of supplemental DHA and 22 % of their daily choline intake as 2H-labelled choline. The effects of reproductive state and choline intake on total LPC-DHA (expressed as a percentage of LPC) and plasma enrichments of labelled LPC and LPC-DHA were assessed using mixed and generalised linear models. Reproductive state interacted with time (P = 0·001) to influence total LPC-DHA, which significantly increased by week 10 in non-pregnant women, but not in pregnant or lactating women. Contrary to total LPC-DHA, patterns of labelled LPC-DHA enrichments were discordant between pregnant and lactating women (P < 0·05), suggestive of unique, reproductive state-specific mechanisms that result in reduced production and/or enhanced clearance of LPC-DHA during pregnancy and lactation. Regardless of the reproductive state, women consuming 930 v. 480 mg choline per d exhibited no change in total LPC-DHA but higher d3-LPC-DHA (P = 0·02), indicating that higher choline intakes favour the production of LPC-DHA from the phosphatidylethanolamine N-methyltransferase pathway of phosphatidylcholine biosynthesis. Our results warrant further investigation into the effect of reproductive state and dietary choline on LPC-DHA dynamics and its contribution to DHA status.

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