New Zealand Journal of Marine and Freshwater Research abstracts
Temperature effects on the embryo development and hatching of the spiny
lobster Sagmariasus verreauxi
Graeme A. Moss
Philip J. James
Sarah E. Allen
Michael P. Bruce
National Institute of Water and Atmospheric
Research Limited
Private Bag 14 901
Kilbirnie
Wellington, New Zealand
email: g.moss@niwa.co.nz
Abstract Factors affecting the development of the embryos
and production of larvae of the spiny lobster Sagmariasus verreauxi
were investigated. Mature lobsters were collected from the fishery in New
Zealand and held in captivity until they moulted, mated, and extruded eggs.
For females, moulting took place in winter (July/August) and mating occurred
58-88 days later in early spring. The ovigerous females were then held at
three temperatures and embryo development monitored at approximately weekly
intervals. Mean times to hatch were 55, 75, and 130 days at 20°C, 17°C,
and 13°C respectively. The total number of larvae that hatched from each
female ranged from 0.97 to 1.4 million. The theoretical temperature at which
embryo development ceases (a biological zero) for S. verreauxi, of
9.4°C, was calculated from data on the appearance of the median eye,
the eyes and the chromatophores, and the time to hatch. An eye index formula
was also derived to allow prediction of time to hatch at a range of temperatures
using the cumulative difference between the rearing temperature and the biological
zero. First instar phyllosomas from embryos reared at 20°C were significantly
smaller than those from 17°C and 13°C but there was no significant
difference in fitness. This study shows that hatching can be spread over a
number of months, without significantly affecting larval quality, simply by
manipulating holding temperature.
Keywords Sagmariasus verreauxi; spiny lobster;
temperature; embryo development; eye index; hatch times
M04097; Online publication date 24 November 2004 Received 20 April 2004;
accepted 19 August 2004
New Zealand Journal of Marine and Freshwater Research, 2004, Vol. 38:
795–801
0028–8330/04/3805–0795 © The Royal Society of New Zealand 2004
PDF file of entire paper: Print-quality (142K) |
screen-quality (94K)
This year's abstracts |
Journal home page |
All abstracts |
Publishing home page
