scholarly journals Distribution, activity and range use of male caribou in early summer in Northern Yukon, Canada

Rangifer ◽  
1986 ◽  
Vol 6 (2) ◽  
pp. 181
Author(s):  
Arthur M. Martell ◽  
Wendy Nixon ◽  
Donald E. Russell

Males of the Porcupine Caribou Herd separated from females from the onset of spring migration until they joined them on the calving grounds in late June or early July, 4-6 weeks later. From late May to late June males spent an average of 50% of their time feeding and less than 2% standing and trotting/running. Males spent an average of 29% of their time lying and 19% walking, except in mid-June (40% lying, 6% walking). The average lengths of active and resting periods were 112 minutes and 104 minutes, respectively, from late May to mid-June, but decreased sharply in late June to 78 minutes and 69 minutes, respectively. Tussock meadows were selected in late May and early June, wet sedge meadows were avoided until late June, dwarf shrub heaths were avoided after late May, and alluvial willow thickets were avoided in late May and early June but were selected in mid-June and late June. Caribou fed primarily on lichens and Vaccinium in late May, lichens and Eriophorum in early June, Eriophorum in mid-June and Salix in late June.

1980 ◽  
Vol 137 (1) ◽  
pp. 47-49 ◽  
Author(s):  
Wolfgang Wiltschko ◽  
Roswitha Wiltschko ◽  
Stephan T. Emlen ◽  
Natalie J. Demong

EDIS ◽  
2019 ◽  
Vol 2019 (5) ◽  
pp. 3
Author(s):  
Ramdas Kanissery ◽  
Biwek Gairhe ◽  
Brent Sellers ◽  
Steve Futch

In Florida, clustered pellitory is becoming a troublesome weed for citrus, especially from the winter through early summer. Inadequate management of this weed can result in its heavy infestation in tree rows and can interrupt the spray pattern of low-volume drip irrigation systems. This new 3-page publication of the UF/IFAS Horticultural Sciences Department will assist Florida citrus growers with proper identification of clustered pellitory and with adoption of adequate and timely strategies to manage this weed in their groves. Written by Ramdas Kanissery, Biwek Gairhe, Brent Sellers, and Steve Futch. https://edis.ifas.ufl.edu/hs1341


2019 ◽  
Vol 16 (1) ◽  
pp. 25-35 ◽  
Author(s):  
N.A. Komaromi ◽  
A.V. Putchkov ◽  
V.Yu. Nazarenko

A total of 54 species in 35 genera of Curculionidae are registered in the urbocenoses of Kharkiv city. Only three species, Exomias pellucidus, Otiorhynchus raucus and Ot. ovatus, are recorded as dominants. Some other species (Urometopus nemorum, Sciaphobus squalidus and Glocianus punctiger) are sporadically noted in some sites as subdominants. The total number of species turned out to be higher in the herpetobios of plantings at periphery (31), slightly lower in private farmlands of the city (21), parks and plantings of the center (17 each), but minimal in suburban forests (11 species). The highest quantity of specimens were observed for the plantations of the center and margins of city: nevertheless, minimal quantity of specimens was registered at parks and woods. The maximum number of species (including all cenoses) was recorded from the end of April to first decade of May (28 species). From May to the end of June 15–18 species were registered. Ten species were recorded at July, and only six species at August. A slight rise was noted from the end of August to mid-September (11 species). In biotopes where Exomias pellucidus appeared to be the monodominant, the seasonal dynamic density of weevils reached a peak at late May or early June, but the significant decline was observed from early June to July. At the sites with several dominants, two or three peaks were registered: at spring (May) and at mid-summer (end of June or beginning of July). Furthermore, the number of weevils decreased gradually, but some species of Curculionidae were rather abundant even from the end of summer to September–October. The spring increase is reasoned by high density of species in the genus Otiorhynchus; the peak in early summer (maximum) is caused by the increased activity of majority of dominant species; the autumn peak is also caused by the high number of species of the genus Otiorhynchus. The level of sex index (by the example of E. pellucidus) differed significantly at all plots. It was higher for the plantations at the periphery of the city (0.70), and it was minimal at private farmlands (0.20). Relative conjugacy of sex index and dynamic density were not observed: the maximum abundances of quantity of Curculionidae were recorded 20–30 days earlier than the maximal numbers of the sex index.


1996 ◽  
Vol 2 (1) ◽  
pp. 247-251 ◽  
Author(s):  
Ingunn M. Tombre ◽  
Kjell E. Erikstad ◽  
Geir W. Gabrielsen ◽  
Karl-Birger Strann ◽  
Jeffrey M. Black

2020 ◽  
Vol 11 (3) ◽  
pp. 215-221
Author(s):  
M. Ramadan ◽  
M. Abd El-Wahed ◽  
Enas Bardisi

1998 ◽  
Vol 37 (2) ◽  
pp. 145-152 ◽  
Author(s):  
A. E. Nienhüser ◽  
P. Braches

Refilling of the Kerspe-Talsperre reservoir after restoration of the dam caused severe problems in water quality and supply due to a long-lasting ice-cover period and minimal precipitation. Unusually short spring overturn, high algal mass in spring and certainly the overflooding of the sediment, which had not been removed, caused a tremendous oxygen deficit in early summer. The whole hypolimnion turned anoxic and even in the metalimnion oxygen declined to a minimum. Manganese and iron reached high concentrations. Despite the poor water quality, raw water was urgently needed for the water supply and was pumped from the epilimnion during the clear water phase and in July when algal biomass was low. In the middle of August holomixis was induced artificially in order to improve water quality. The decline in algal production during and after artificial mixing was probably caused by light limitation of the algae.


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