© 1994 International Society for Behavioral Ecology
research-article |
Death and disappearance: estimating mortality risks associated with philopatry and dispersal
Department of Biological Sciences, Purdue University West Lafayette, IN 47907, USA
ABSTRACT
Models dealing with the relationship of inbreeding to dispersal, the evolution of cooperative breeding, and the adaptive significance of reproductive suppression all involve a parameter describing die probability that emigration ends in death. Surprisingly, estimates of this parameter (or equivalently, of the probability of dispersing successfully) are virtually absent from the literature. There are formidable difficulties in estimating dispersal risk by direct observation of emigrants, but we contend that many investigators have already collected demographic information that can be used to estimate it indirectly. The root problem is that the proportion of the population diat emigrates from its natal group or home range, e, is not generally observable. Nevertheless, for each value of e diere is only one possible survival rate of emigrants (st) and of philopatric animals (sf) diat can explain the overall survival rate. For study sites Uiat are neither sources nor sinks, we describe a graphical framework within which census data and behavioral observations can be used to place bounds on e, s, and sp. We use data from a Serengeti population of the dwarf mongoose (Helogale parvula) to illustrate how different types of data and assumptions allow us to construct better estimates of these parameters. For dwarf mongooses, die approach reveals unexpected differences in dispersal risk among sex and age classes
Key words: cooperative breeding, dispersal, dispersal cost, dispersal risk, emigration, Helogall, Herpestidae, immigration, inbreeding avoidance, mongoose, mortality, Serengeti.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
P. Ferreras, M. Delibes, F. Palomares, J. M. Fedriani, J. Calzada, and E. Revilla Proximate and ultimate causes of dispersal in the Iberian lynx Lynx pardinus Behav. Ecol., January 1, 2004; 15(1): 31 - 40. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. C. B. Andrade Risky mate search and male self-sacrifice in redback spiders Behav. Ecol., July 1, 2003; 14(4): 531 - 538. [Abstract] [Full Text] [PDF] |
||||
