Spacing and calling in Pacific tree frogs, Hyla regilla

1975 ◽  
Vol 53 (11) ◽  
pp. 1519-1527 ◽  
Author(s):  
Carl L. Whitney ◽  
John R. Krebs
Keyword(s):  
Local Area ◽  
Hyla Regilla ◽  
Behavioral Interactions ◽  
Mating Call ◽  
Control Situation ◽  
Tree Frogs ◽  
Empty Area

Calling male Pacific tree frogs space out more than if they were distributed at random on the available calling sites. When new frogs are added to an area that is already occupied by some calling males, fewer additional frogs call than in a control situation where frogs are added to an empty area. This shows that behavioral interactions between frogs limit the number that call in a local area. A further experiment showed that the mating call played through loudspeakers is sufficient to inhibit additional frogs from calling. We conclude that calling leads to spacing out, which in turn limits the density of calling frogs in a local area.

The role of the "encounter" call in spacing of Pacific tree frogs, Hyla regilla

1980 ◽  
Vol 58 (1) ◽  
pp. 75-78 ◽  
Author(s):  
Carl L. Whitney
Keyword(s):  
Hyla Regilla ◽  
Mating Call ◽  
Mating Calls ◽  
Tree Frogs

When calling male Pacific tree frogs come closer together than about 50 cm, they switch from the mating call to the encounter call. After an exchange of encounter calls, one of the frogs may submit by retreating or ceasing to call, or they may fight, after which the loser submits. To investigate the role of the encounter call in maintaining spacing, I compared the responses of calling males lo playback of encounter calls and mating calls. During 60-s playbacks, most frogs responded initially to both vocalizations by uttering encounter calls, but they were more likely to respond further to encounter calls by either attacking or submitting. I suggest that the encounter call serves to reduce the amount of time that calling frogs remain close together and, as a consequence, to enhance their chances of attracting females.

Social Interaction among Chorusing Pacific Tree Frogs, Hyla regilla

Copeia ◽  
1978 ◽  
Vol 1978 (2) ◽  
pp. 208 ◽  
Author(s):  
Frank T. Awbrey
Keyword(s):  
Social Interaction ◽  
Hyla Regilla ◽  
Tree Frogs

'Handedness' in the Pacific tree frog (Hyla regilla)

1977 ◽  
Vol 55 (11) ◽  
pp. 1926-1929 ◽  
Author(s):  
Lawrence M. Dill
Keyword(s):  
Tree Frog ◽  
Hyla Regilla ◽  
The Pacific ◽  
The Mean ◽  
Tree Frogs ◽  
The Right ◽  
Model Predator

The jumping directions of 24 individual Pacific tree frogs (Hyla regilla), in response to repeated presentations of a model predator, were recorded. The mean jump angle was 70° from the frog's initial bearing regardless of whether the jump was to the left or the right. There was a slight bias within the sample towards left jumps, and most frogs had longer right than left hindlimbs. Some individual frogs jumped preferentially to the left, indicating the existence of 'handedness' in this species.

Strathnet—a local area network

1981 ◽  
Vol 1 (1) ◽  
pp. 21 ◽  
Author(s):  
David Hutchison ◽  
Doug Shepherd
Keyword(s):  
Local Area Network ◽  
Local Area ◽  
Area Network

A Local Area Network for Medical Research; Planning, Realization and Experience

1991 ◽  
Vol 30 (01) ◽  
pp. 53-64 ◽  
Author(s):  
R. Schosser ◽  
C. Weiss ◽  
K. Messmer
Keyword(s):  
Medical Research ◽  
Word Processing ◽  
Local Area Network ◽  
Local Area ◽  
Area Network ◽  
Test Installation ◽  
Cost Performance ◽  
The Public ◽  
On Line ◽  
The University

This report focusses on the planning and realization of an interdisciplinary local area network (LAN) for medical research at the University of Heidelberg. After a detailed requirements analysis, several networks were evaluated by means of a test installation, and a cost-performance analysis was carried out. At present, the LAN connects 45 (IBM-compatible) PCs, several heterogeneous mainframes (IBM, DEC and Siemens) and provides access to the public X.25 network and to wide-area networks for research (EARN, BITNET). The network supports application software that is frequently needed in medical research (word processing, statistics, graphics, literature databases and services, etc.). Compliance with existing “official” (e.g., IEEE 802.3) and “de facto” standards (e.g., PostScript) was considered to be extremely important for the selection of both hardware and software. Customized programs were developed to improve access control, user interface and on-line help. Wide acceptance of the LAN was achieved through extensive education and maintenance facilities, e.g., teaching courses, customized manuals and a hotline service. Since requirements of clinical routine differ substantially from medical research needs, two separate networks (with a gateway in between) are proposed as a solution to optimally satisfy the users’ demands.

Sign in / Sign up

Export Citation Format

Share Document