IMIS

Publications | Institutes | Persons | Datasets | Projects | Maps
[ report an error in this record ]basket (0): add | show Print this page

A statistical procedure for estimating grey seal pup production from a single census
Radford, P.J.; Summers, C.F.; Young, K.M. (1978). A statistical procedure for estimating grey seal pup production from a single census. Mamm. Rev. 8(1-2): 35-42. https://dx.doi.org/10.1111/j.1365-2907.1978.tb00214.x
In: Mammal Review. Blackwell: Oxford. ISSN 0305-1838; e-ISSN 1365-2907, more
Peer reviewed article  

Available in  Authors 

Keywords
    Analysis > Mathematical analysis > Statistical analysis
    Developmental stages > Juveniles > Pups
    Population dynamics
    Halichoerus grypus (Fabricius, 1791) [WoRMS]
    Marine/Coastal

Authors  Top 
  • Radford, P.J.
  • Summers, C.F.
  • Young, K.M.

Abstract
    The variable start and duration of the grey seal (Halichoerus grypus) breeding season makes the estimation of total pup production from a single census very difficult. Classifying the count into morphological age classes enables the form and timing of the birth rate curve and estimates of pup mortality rates to be elucidated. A simulation technique is described which enables the duration of each morphological stage to be determined from a series of such classified counts taken over one season. A further statistical technique uses these estimates to calculate the mean timing and duration of the breeding season from a single classified count taken from similar populations in subsequent years. This information allows total pup production to be calculated for any appropriate breeding colony. Some guidance is given as to the optimal timing of that single census which would yield the best estimate of production, although the precise date is not critical to the success of the technique. Results from single census estimates obtained in this way are compared with known production data from more detailed surveys for a number of different colonies.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors