A. Stien, Effects of the parasitic nematode Echinomermella matsi on growth and survival of its host, the sea urchin Strongylocentrotus droebachiensis, CAN J ZOOL, 77(1), 1999, pp. 139-147
Citations number
49
Categorie Soggetti
Animal Sciences
Journal title
CANADIAN JOURNAL OF ZOOLOGY-REVUE CANADIENNE DE ZOOLOGIE
It has been suggested that the parasitic nematode Echinomermella matsi sign
ificantly affects the population dynamics of its host, the sea urchin Stron
gylocentrotus droebachiensis. The effects of infection on both host fecundi
ty and host survival may be of importance. The fecundity of sea urchins is
related to their size. Negative effects of infection on host growth will th
erefore reduce reproductive rates. I estimated the effect of infection on h
ost growth and survival in two naturally infected wild sea urchin populatio
ns using a capture-mark-recapture approach. Infected and uninfected sea urc
hins were captured and marked with unique tags or recaptured seven times fr
om June 1994 to September 1996. The increment in the diameter of marked sea
urchins between captures was used to measure sea urchin growth. The effect
of E. matsi infection on host growth was small. Mortality rates were estim
ated using survival probability models based on the methodology developed b
y Cormack, Jolly, and Seber. The effect of infection on host survival was p
ronounced, with estimated sea urchin Life expectancies reduced by 33-86% by
E. matsi infection. This suggests that E. matsi may affect the population
dynamics of S. droebachiensis significantly through the effect on host surv
ival.