Seasonal Population Fluctuations of Serangium parcesetosum (Coleoptera: Coccinellidae), a Predator of Citrus Whitefly, Dialeurodes citri (Homoptera: Aleyrodidae) in Turkey’s Eastern Mediterranean Citrus Groves

2003 ◽  
Vol 32 (5) ◽  
pp. 1105-1114 ◽  
Author(s):  
Abdurrahman Yigit ◽  
Ramazan Canhilal ◽  
Ugur Ekmekci
Keyword(s):  
Eastern Mediterranean ◽  
Population Fluctuations ◽  
Serangium Parcesetosum ◽  
Citrus Groves ◽  
Dialeurodes Citri ◽  
Seasonal Population

scholarly journals Seasonal population dynamics of Octopus vulgaris in the eastern Mediterranean

2006 ◽  
Vol 63 (1) ◽  
pp. 151-160 ◽  
Author(s):  
Stelios Katsanevakis ◽  
George Verriopoulos
Keyword(s):  
Eastern Mediterranean ◽  
Late Summer ◽  
Main Peak ◽  
Octopus Vulgaris ◽  
Late Winter ◽  
Visual Census ◽  
The Common ◽  
Specific Growth Rates ◽  
Seasonal Population ◽  
Seasonal Population Dynamics

Abstract The population density of Octopus vulgaris was measured by visual census with scuba diving in coastal areas in Greece (eastern Mediterranean). A time-variant, stage-classified, matrix population model was developed to interpret the seasonal variation of octopus stage densities and to estimate several life cycle parameters. An annual and a semi-annual periodic cycle were found in the stage densities. A main peak of benthic settlement was observed during summer and a secondary, irregular one during late autumn. Two spawning peaks were estimated, a main one during late winter–spring and a secondary one during late summer–early autumn. More than 50% of the just-settled individuals will eventually die after 3 months. Mortality rate declines, as individuals grow larger, reaches a minimum approximately 6 months after settlement, and then grows again probably because of terminal spawning. The life expectancy of recently settled individuals (<50 g) during their summer peak is approximately 5 months. The lifespan of the common octopus is estimated to be between 12 and 15 months. The octopuses' mean specific growth rates (±s.d.) in their natural environment were 1.61 ± 0.30 d−1 for 50–200 g individuals and 1.19 ± 0.31 d−1 for 200–500 g individuals.

Life cycles and larval behavior of two species of Hydrachna (Acari, Hydrachnidae), parasitic upon Corixidae (Hemiptera–Heteroptera)

1974 ◽  
Vol 52 (9) ◽  
pp. 1155-1165 ◽  
Author(s):  
D. A. Harris ◽  
A. D. Harrison
Keyword(s):  
Mite Species ◽  
Life Cycles ◽  
Population Fluctuations ◽  
Seasonal Fluctuations ◽  
Larval Behavior ◽  
Free Living ◽  
Population Distributions ◽  
Attachment Sites ◽  
Permanent Pond ◽  
Seasonal Population

The seasonal population fluctuations, population distributions, and pattern of attachment of the larvae of two species of Hydrachna parasitic upon Sigara solensis Abbott and Sigara modesta Hungerford were investigated in a permanent pond in Waterloo County, Ontario, throughout 1969. Seasonal fluctuations of parasitism occurred as a result of the fluctuations in the numbers of the free-living larvae and of the corixid hosts. Analysis of the intensity distribution of the larvae on their hosts fitted the data to a Poisson distribution. The parasitic larvae of the two mite species were evenly distributed over most of the potential attachment sites on their hosts. Absence, or reduced numbers, of larvae at any site has been explained in terms of nonavailability of the site to parasitism as a result of host behavior or physical unsuitability.

Breeding Biology and Seasonal Population Changes of Jaera Nordmanni Nordica Lemercier [Isopoda, Asellota]

1974 ◽  
Vol 54 (3) ◽  
pp. 727-736 ◽  
Author(s):  
M. B. Jones
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Breeding Biology ◽  
Population Fluctuations ◽  
Population Changes ◽  
The West ◽  
Freshwater Streams ◽  
Male Sex ◽  
Seasonal Population ◽  
Scanning Electron

Jaera nordmanni (Rathke) occurs abundantly beneath stones and algae in freshwater streams (McCartan & Slinn, 1953), brackish water pools (Naylor & Slinn, 1958), and estuaries (Naylor, Slinn & Spooner, 1961; Harvey, Jones & Naylor, 1973). The species is widely distributed and ranges from the Black and Mediterranean Seas south to the Azores, and north to the west coast of Scotland (Naylor, 1972). Three forms of J. nordmanni have been described (Lemercier, 1958, i960) of which only Jaera nordmanni nordica Lemercier has been recorded in Britain (Naylor, 1972; Jones & Fordy, 1973). The two other forms, Jaera nordmanni nordmanni Lemercier and Jaera nordmanni massiliensis Lemercier, have a more southerly distribution (Naylor, 1972), and can be separated from J. nordmanni nordica by differences in male sex characters (Lemercier, 1958, 1960; Jones & Fordy, 1973). Apart from some eco-physiological work (Naylor et al. 1961; Harvey et al. 1973) and a recent study with a scanning electron microscope (Jones & Fordy, 1973), little is known of the biology of J. nordmanni. The present paper reports on the breeding biology and seasonal population fluctuations of Jaera nordmanni nordica, and compares the results with a similar study on the members of the Jaera albifrons Leach group of species (Jones & Naylor, 1971) which are closely related to and often in competition with J. nordmanni.

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