Cognitive tests can be carried out with birds in their natural habitat: An approach exampled by experiments with the Glaucous-winged Gull (Larus glaucescens) on the Toporkov Island

2009 ◽  
Author(s):  
Tanya Obozova ◽  
Anna Smirnova ◽  
Zoya Zorina
2012 ◽  
Vol 15 (3) ◽  
pp. 873-880
Author(s):  
Tatyana A. Obozova ◽  
Anna A. Smirnova ◽  
Zoya A. Zorina

An experimental approach was created for the comparative investigation of the cognitive abilities of the glaucous-winged gull (Larus glaucescens) in their natural habitat. The territoriality of gulls during the breeding period and the fact that the gulls inhabiting the territory of the Komandorsky Reserve are practically not in fear of humans allowed us to work with individually recognized birds directly at their nest sites inside the colony. The possibility of using this approach to investigate their cognitive abilities was demonstrated on 24 gulls, in particular, to investigate their abilities for relative size generalization. The first experiment illustrated that the gulls are able to learn to discriminate two pairs of stimuli according to the feature: ‘larger’ or ‘smaller’. They were then given a test to transfer the discriminative rule in which novel combinations of the same stimuli were used. The gulls successfully coped with only a few of these tests. In the next experiment the birds were taught to discriminate four pairs of similar stimuli. The majority of the birds coped with the tests to transfer the discriminative rule both to the novel combinations of familiar stimuli, and also to the novel stimuli of the familiar category (items of different colour and shape). However, none of the birds transferred the discriminative rule to stimuli of a novel category (sets differing by number of components). Thus, in their ability to generalize at a preconceptual level gulls are more comparable with pigeons, whereas large-brained birds (crows and parrots), are capable of concept formation.


Author(s):  
L. P. Hardie ◽  
D. L. Balkwill ◽  
S. E. Stevens

Agmenellum quadruplicatum is a unicellular, non-nitrogen-fixing, marine cyanobacterium (blue-green alga). The ultrastructure of this organism, when grown in the laboratory with all necessary nutrients, has been characterized thoroughly. In contrast, little is known of its ultrastructure in the specific nutrient-limiting conditions typical of its natural habitat. Iron is one of the nutrients likely to limit this organism in such natural environments. It is also of great importance metabolically, being required for both photosynthesis and assimilation of nitrate. The purpose of this study was to assess the effects (if any) of iron limitation on the ultrastructure of A. quadruplicatum. It was part of a broader endeavor to elucidate the ultrastructure of cyanobacteria in natural systemsActively growing cells were placed in a growth medium containing 1% of its usual iron. The cultures were then sampled periodically for 10 days and prepared for thin sectioning TEM to assess the effects of iron limitation.


2013 ◽  
Author(s):  
Jacqueline M. Caemmerer ◽  
Timothy Keith ◽  
Alexandra L. Fisher
Keyword(s):  

2018 ◽  
Vol 30 (3) ◽  
pp. 328-338 ◽  
Author(s):  
Maria Bertling ◽  
Jonathan P. Weeks

Author(s):  
I.G.C. Kerr ◽  
J.M. Williams ◽  
W.D. Ross ◽  
J.M. Pollard

The European rabbit (Oryctolagus cuniculus) introduced into New Zealand in the 183Os, has consistently flourished in Central Otago, the upper Waitaki, and inland Marlborough, all areas of mediterranean climate. It has proved difficult to manage in these habitats. The 'rabbit problem' is largely confined to 105,000 ha of low producing land mostly in semi arid areas of Central Otago. No field scale modifications of the natural habitat have been successful in limiting rabbit numbers. The costs of control exceed the revenue from the land and continued public funding for control operations appears necessary. A system for classifying land according to the degree of rabbit proneness is described. Soil survey and land classification information for Central Otago is related to the distribution and density of rabbits. This intormation can be used as a basis for defining rabbit carrying capacity and consequent land use constraints and management needs. It is concluded that the natural rabbit carrying capacity of land can be defined by reference to soil survey information and cultural modification to the natural vegetation. Classification of land according to rabbit proneness is proposed as a means of identifying the need for, and allocation of, public funding tor rabbit management. Keywords: Rabbit habitat, rabbit proneness, use of rabbit prone land.


2016 ◽  
Vol 52 (2) ◽  
pp. 71-82 ◽  
Author(s):  
G. I. Falfyshynska ◽  
L. L. Gnatyshyna ◽  
I. V. Yurchak ◽  
A. Ye. Mudra ◽  
A. Ivanina ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document