High densities and brood rearing in the antMyrmica rubra L.

1973 ◽  
Vol 20 (2) ◽  
pp. 109-123 ◽  
Author(s):  
Angela F. Kelly ◽  
A. F. Stebbings
Keyword(s):  
2021 ◽  
Vol 67 (4) ◽  
Author(s):  
Gianpasquale Chiatante ◽  
Marta Giordano ◽  
Anna Vidus Rosin ◽  
Oreste Sacchi ◽  
Alberto Meriggi

AbstractMore than half of the European population of the Barbary Partridge is in Sardinia; nonetheless, the researches concerning this species are very scarce, and its conservation status is not defined because of a deficiency of data. This research aimed to analyse the habitat selection and the factors affecting the abundance and the density of the Barbary Partridge in Sardinia. We used the data collected over 8 years (between 2004 and 2013) by spring call counts in 67 study sites spread on the whole island. We used GLMM to define the relationships between the environment (topography, land use, climate) both the occurrence and the abundance of the species. Moreover, we estimated population densities by distance sampling. The Barbary Partridge occurred in areas at low altitude with garrigue and pastures, avoiding woodlands and sparsely vegetated areas. We found a strong relationship between the occurrence probability and the climate, in particular, a positive relation with temperature and a negative effect of precipitation, especially in April–May, during brood rearing. Furthermore, dry crops positively affected the abundance of the species. We estimated a density of 14.1 partridges per km2, similar to other known estimates. Our findings are important both because they increase the knowledge concerning this species, which is considered data deficient in Italy, and because they are useful to plan management actions aimed to maintain viable populations if necessary.


2021 ◽  
Author(s):  
Kade D. Lazenby ◽  
Peter S. Coates ◽  
Shawn T. O’Neil ◽  
Michel T. Kohl ◽  
David K. Dahlgren

1994 ◽  
Vol 72 (9) ◽  
pp. 1294-1301 ◽  
Author(s):  
Christopher A. Babcock ◽  
Craig R. Ely

Plant communities are described from an area on the Yukon – Kuskokwim (Y-K) delta of Alaska that is used extensively for brood rearing by three species of geese. Earlier studies identified plant species important as food for young geese, but few studies describe or quantify plant communities. We classified species presence or absence information from over 700 quadrats using a two-way indicator species analysis (TWINSPAN) and then tested for agreement of signatures on colour infrared air photos with the identified communities. Sedges were found to dominate all but the wettest and driest communities. Most of the brood-rearing area was covered by Carex ramenskii and Carex rariflora meadows, ponds, Carex mackenziei-dominated pond margins, and C. ramenskii and grass levee meadows. Our interpretation of airphotos accurately predicted vegetation community classes, which will facilitate future studies of habitat selection by geese during the time they are rearing young. The TWINSPAN classification was comparable to classifications of studies conducted elsewhere on the Y-K delta. The interpretation of air photos will enable the identification and evaluation of wetland vegetation complexes and potential goose brood-rearing areas away from our study site. Key words: air-photo interpretation, Alaska, plant communities, salt marsh, Yukon – Kuskokwim delta.


1982 ◽  
Vol 46 (3) ◽  
pp. 615 ◽  
Author(s):  
James K. Ringelman ◽  
Jerry R. Longcore
Keyword(s):  

2016 ◽  
Vol 5 (1) ◽  
pp. 126
Author(s):  
Jennifer Woodward ◽  
Jenny Sika ◽  
Carl Wambolt ◽  
Jay Newell ◽  
Sean Schroff ◽  
...  

<p class="emsd"><span lang="EN-GB">Greater sage-grouse (Centrocercus urophasianus) habitat characteristics were studied in central Montana primarily on Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle &amp; Young) dominated rangeland. The primary objective was to compare shrub and herbaceous parameters within (use, random or non-use) and between seasonal habitats (nest, brood, winter). Two study sites (Musselshell and Golden Valley counties), and 2 years (2004 and 2005) were compared. Nest, brood, and random sites were compared for herbaceous cover, and grass height (n = 648). Nest, brood, random, winter use and winter non-use sites were evaluated for shrub cover, density, and height. All differences were considered significant at P ≤ 0.05. Sage-grouse nested in areas with greater total shrub cover and height, and taller live and residual grass than was randomly available. No differences were found between brood and paired random sites for any of the herbaceous or shrub parameters measured. Shrub cover and density were greater at winter use sites than non-use sites. Winter use sites had less shrub cover than nest sites. The nest and brood habitat had similar shrub cover, density, and height on the study area. Sage-grouse habitats should be managed to include sagebrush, forbs, and grass. Herbaceous vegetation was more important during nesting and brood rearing than during the winter. Therefore, some portions of <span>sage-</span>grouse habitat may benefit from management for greater herbaceous cover, but not at the expense of removing sagebrush. Sagebrush cover from 10 to 15 percent was the most consistent component of sage-grouse habitat.</span></p>


Apidologie ◽  
1983 ◽  
Vol 14 (3) ◽  
pp. 191-196 ◽  
Author(s):  
Elton W. HERBERT ◽  
H. SHIMANUKI
Keyword(s):  

1983 ◽  
Vol 22 (3) ◽  
pp. 163-168 ◽  
Author(s):  
Frank A. Eischen ◽  
Walter C. Rothenbuhler ◽  
Jovan M. Kulinčević
Keyword(s):  

Author(s):  
Christoph Grüter
Keyword(s):  

2021 ◽  
pp. 183-191
Author(s):  
Lucas R. Hearn ◽  
Mark I. Stevens ◽  
Michael P. Schwarz ◽  
Ben A. Parslow

Understanding how nest parasites contribute to brood mortality rates in host species is an important step towards uncovering the potential implications for host behaviour. This can be especially important for understanding the evolution of social living, where defence against parasites is often posited as a major benefit of cooperative nesting. Only two parasitoid species have previously been reported for the only known social colletid bee, Amphylaeus morosus: the gasteruptiid wasp, Gasteruption primotarsale, and the mutillid, Ephutomorpha tyla. Here we report six additional parasitoid species of A. morosus: the gasteruptiid wasps G. atrinerve, G. globiceps, G. melanopoda and G. cinerescens; the bombyliid fly Anthrax maculatus; and the mutillid wasp Ephutomorpha aff. varipes. The mechanisms of parasitism for these eight parasitoid species are described in combination with how they operate throughout the host brood rearing period and whether benefits of social nesting vary across the season.


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