Journal
FISHERIES RESEARCH
Volume 89, Issue 3, Pages 266-275Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.fishres.2007.09.006
Keywords
Zygochlamys patagonica; scallops; internal shell growth bands; acetate peels; age
Categories
Ask authors/readers for more resources
Shell morphometry, internal shell growth patterns and growth rates of the Patagonian scallop Zygochlamys patagonica from four different beds across their SW Atlantic distribution range were compared. The northern beds (Uruguay, WITS and Reclutas, 39 degrees 25') showed lower shell height, length and shell mass than the southern populations (Tango B bed: 42 degrees 30' and Beagle bed: 55 degrees 10'S). Mean height, length, and width increased following a N-S latitudinal gradient. Acetate peels revealed the presence of internal growth bands with alternating broad opaque and narrow translucent growth bands. In the Reclutas bed, the cluster of translucent bands representing external rings was formed mainly during winter at the same time of the higher gonadal condition index, and a regional decrease in food availability. The growth pattern observed for the first two or three growth bands was less pronounced than other growths bands, with sizes of these individuals corresponding to first maturity of the species. Thus, differences can be due to differential allocation of energy investment to shell production between juvenile and adult organisms. The internal growth patterns and maximum age differed between beds, with an increase in the maximum age from the N to the S (Uruguay bed: 13 years old, Reclutas bed: 14 years old, Tango B bed: 20 years old, Beagle bed: 21 years old). Our study provides evidence of variation of growth in Z patagonica in the four main beds across their SW Atlantic distribution range, where a significant increase in H. from N to S coincides with different internal growth pattern, maximum age and a trend toward higher von Bertalanffy k parameter in the northern beds. (c) 2007 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available