Seasonal abundance and prey selection of the nymphs of three sympatric species of Sympetrum (Odonata: Libellulidae) in an intermittent pond

2005 ◽  
Vol 137 (6) ◽  
pp. 723-727 ◽  
Author(s):  
Catherine M. Febria ◽  
A. Katarina Magnusson ◽  
D. Dudley Williams
Keyword(s):  
Life Cycle ◽  
Prey Selection ◽  
Sympatric Species ◽  
Early Spring ◽  
Seasonal Abundance ◽  
Gut Contents ◽  
Southern Ontario ◽  
Size Data ◽  
Selection Of

Odonates are obligate predators (Pritchard 1964), and the composition of their diet is reflective of their microhabitat and effectiveness in detecting and capturing prey (Griffiths 1973; Thompson 1978). In an intermittent woodland pond in southern Ontario, Canada, three species of Sympetrum (Odonata: Libellulidae) were found to coexist: S. internum Montgomery, S. costiferum (Hagen), and S. obtrusum (Hagen). Sympetrum species spend most of their life cycle in the aquatic stage and consume prey at all nymphal stadia (Pritchard 1964; Corbet 1999). They overwinter in the egg stage, hatch in early spring, and typically emerge in late June to late July (Walker and Corbet 1975). To better understand the role of coexisting Sympetrum nymphs in this intermittent pond environment, and to evaluate potential mechanisms behind their coexistence, we collected seasonal abundance and body size data for 2 years and analyzed gut contents of each species. In addition, we experimentally tested the prey selection and predatory rate of two different size classes of Sympetrum nymphs and two of their potential competitors, Lestes sp. (Odonata: Lestidae) and Acilius sp. (Coleoptera: Dytiscidae), in laboratory microcosms.

Seasonal Abundance and Population Dynamics of a Bamboo Aphid, Takecallis arundinaria (Homoptera: Aphididae)

1990 ◽  
Vol 25 (4) ◽  
pp. 526-534 ◽  
Author(s):  
Mark A. Coffelt ◽  
Peter B. Schultz
Keyword(s):  
Population Dynamics ◽  
Life Cycle ◽  
Plant Species ◽  
Woody Plant ◽  
Early Spring ◽  
Climatic Conditions ◽  
Seasonal Abundance ◽  
Alternate Host ◽  
Woody Plant Species ◽  
Aphid Populations

The anholocyclic life cycle of the aphid Takecallis arundinaria (Essig) on golden stem bamboo, Phyllostachys aurea (Carrie're) was investigated in 1987 – 1988. Aphid populations peaked from March – May, declined from June – October, and peaked again in December. Aphid population dynamics were strongly influenced by climatic conditions. When aphid populations were at constant or rising levels, significantly more nymphs were found in the southern and eastern quadrants, than in the northern and western quadrants. This directionality may have allowed T. arundinaria populations to be exposed to increased sunlight and decreased winds during the winter and early spring periods. Alate viviparae had a mean fecundity of 147 nymphs and a longevity of 46.5 days. Predators were few and no parasites were found. An alternate host study revealed no aphids on yellow sticky traps placed on nine woody plant species.

Studies on Ergasilus labracis Krøyer (Cyclopidea: Ergasilidae) parasitic on striped bass, Morone saxatilis, from the lower Chesapeake Bay. I. Distribution, life cycle, and seasonal abundance

1976 ◽  
Vol 54 (4) ◽  
pp. 449-462 ◽  
Author(s):  
I. Paperna ◽  
D. E. Zwerner
Keyword(s):  
Life Cycle ◽  
Chesapeake Bay ◽  
Striped Bass ◽  
Egg Production ◽  
Developmental Stages ◽  
Morone Saxatilis ◽  
Early Spring ◽  
Seasonal Abundance ◽  
Free Living ◽  
Winter Peak

Information on the distribution, life cycle, and seasonal abundance of the copepod Ergasilus labracis Krøyer, parasitic on the gills of lower Chesapeake Bay striped bass, Morone saxatilis (Walbaum), is presented after a 12-month survey. The overall prevalence of E. labracis was 90% in all localities sampled and it was found to be as euryhaline as its host; it has been found in salinities from 0.l‰ to 32.0‰. E. labracis was present and reproductively active throughout the year, suffering only a temporary slowdown in egg production at the beginning of the winter. Peak invasion of striped bass gills by infective larvae occurred during April and May; minor peaks were also recorded during July and October. The free-living stage was estimated to last as long as 6 weeks during early spring. Duration of other developmental stages was also extrapolated. Attempts to rear larvae in the laboratory past the metanauplius stage failed. Larvae could be kept for a maximum of 23 days after hatching if fed nannoplankton and kept at 20 °C in river water of 16–18‰.

Growth rates and prey selection of two congeneric predatory caddisflies (Trichoptera: Rhyacophilidae)

1983 ◽  
Vol 61 (4) ◽  
pp. 895-900 ◽  
Author(s):  
Ian D. Martin ◽  
Rosemary J. Mackay
Keyword(s):  
Growth Rates ◽  
Laboratory Experiments ◽  
Prey Selection ◽  
Southern Ontario ◽  
Weight Gains ◽  
Prey Organism ◽  
Selection Of

Rhyacophila fuscula (Walker) and R. melita Ross inhabit cool southern Ontario streams, often together. In laboratory experiments, R. fuscula and R. melita showed significant weight gains in 2 weeks on four common prey taxa occurring in the field (Diptera: Chironomidae and Simuliidae; Ephemeroptera: Baetidae; and Trichoptera: Hydropsychidae). Rhyacophila melita grew significantly less than R. fuscula on three prey, but significantly better on Chironomidae. The prey eliciting highest growth rates from R. fuscula (Prosimulium, Baetis) and R. melita (Chironomidae) are most abundant in the habitats occupied by each of these predators. Prosimulium and Baetis are common on the surface of rocks in headwater regions where R. fuscula are at high densities, and chironomids are the most abundant prey organism in the marl (travertine) microhabitat of R. melita farther downstream. Where the two predators co-occur, they may compete for foraging areas in the spring, when prey and microhabitat resources are reduced by flood scour.

Diet, Prey Selection and Foraging Behaviour of the Orange Horseshoe-Bat, Rhinonycteris Aurantius.

1994 ◽  
Vol 21 (2) ◽  
pp. 115 ◽  
Author(s):  
SK Churchill
Keyword(s):  
Foraging Behaviour ◽  
Niche Breadth ◽  
Prey Selection ◽  
Seasonal Abundance ◽  
Light Traps ◽  
Timing Of Reproduction ◽  
Dietary Preferences ◽  
Faecal Analysis ◽  
Horseshoe Bat ◽  
Selection Of

Results of faecal analysis were compared with insect captures in light traps to examine the dietary preferences of R. aurantius in the Northern Territory, Australia. Relative proportions of insects eaten differed significantly from insects available. R. aurantius exhibited a medium niche breadth throughout the year, being neither a specialist not a generalist. It selectively foraged on Lepidoptera and Coleoptera, and was opportunistic in regard to seasonal abundances of Isoptera. This bat had dietary preferences similar to other members of the Hipposideridae. The timing of reproduction and selection of roost sites was related to the seasonal abundance of food resources.

scholarly journals The role of volatile organic compounds in the polluted urban atmosphere of Bristol, England

2003 ◽  
Vol 3 (4) ◽  
pp. 1165-1176 ◽  
Author(s):  
A. C. Rivett ◽  
D. Martin ◽  
D. J. Gray ◽  
C. S. Price ◽  
G. Nickless ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Late Summer ◽  
Early Spring ◽  
Urban Atmosphere ◽  
Electron Capture Detection ◽  
Night Time ◽  
Urban Background ◽  
Flame Ionisation ◽  
Selection Of

Abstract. The results of a field campaign carried out from early spring through to the late summer of 2000, in Bristol, England, are presented. Continuous measurements of over 40 hydrocarbons have been made at an urban background site, located at Bristol University, for approximately nine months using a Gas Chromatography - Flame Ionisation Detection (GC-FID) system and for a selection of halocarbons for approximately one month using a Gas Chromatography - Electron Capture Detection (GC-ECD) system. In this paper we present the time-series of the nine halocarbons and selected hydrocarbons. Daytime and night-time hydroxyl radical concentrations have been estimated based on the diurnal variations of a selection of the measured hydrocarbons. The average summer daytime concentration of OH was found to be 2.5x106 molecules cm-3 and the night-time concentration to be in the range 104 to 105 molecules cm-3. In addition, the role played by certain VOCs in the formation of ozone is assessed using the POCP (Photochemical Ozone Creation Potential) concept.

scholarly journals The role of volatile organic compounds in the polluted urban atmosphere of Bristol, UK

2003 ◽  
Vol 3 (1) ◽  
pp. 769-796 ◽  
Author(s):  
A. C. Rivett ◽  
D. Martin ◽  
D. J. Gray ◽  
C. S. Price ◽  
G. Nickless ◽  
...  
Keyword(s):  
Late Summer ◽  
Early Spring ◽  
Urban Atmosphere ◽  
Night Time ◽  
Urban Background ◽  
Background Site ◽  
Volatile Organic ◽  
Urban Background Site ◽  
Selection Of

Abstract. The results of a field campaign carried out from early spring through to the late summer of 2000, in Bristol, England, are presented. Continuous measurements of over 40 hydrocarbons have been made at an urban background site, located at Bristol University, for approximately nine months using a GC-FID system and for a selection of halocarbons for approximately one month using a GC-ECD system. In this paper we present the time-series of the nine halocarbons and selected hydrocarbons. Daytime and night-time hydroxyl radical concentrations have been estimated based on the diurnal variations of a selection of the measured hydrocarbons. The average summer daytime concentration of OH was found to be 2.5×106 molecules cm−3 and the night-time concentration to be in the range 104 to 105 molecules cm−3. In addition, the role played by certain VOCs in the formation of ozone is assessed using the POCP (Photochemical Ozone Creation Potential) concept.

Late Majority and Laggards

2008 ◽  
pp. 245-257
Author(s):  
Toru Higuchi ◽  
Marvin Troutt
Keyword(s):  
Life Cycle ◽  
Lower Price ◽  
Manufacturing Facility ◽  
Selection Of

The characteristics and the role of the late majority and laggards are discussed in this chapter. Both of them adopt the product later than others and purchase a practical product at a lower price. Although their population is huge, their impact on the market is not big because various types of customers exist in the market. Manufacturers offer a wide selection of products for various customers. The late majority and the laggards are a part of all customers. In addition, most manufacturers finish enlarging their manufacturing facility before the late majority purchases occur. However, from the view of the life cycle, they play an important role as a last purchaser including the repeat purchases.

Faculty selection of textbooks: Key variables and the role of teaching experience

2010 ◽  
Author(s):  
Aja Taitano ◽  
Bradley Smith ◽  
Cade Hulbert ◽  
Kristin Batten ◽  
Lalania Woodstrom ◽  
...  
Keyword(s):  
Teaching Experience ◽  
Key Variables ◽  
Faculty Selection ◽  
Selection Of
Sign in / Sign up

Export Citation Format

Share Document