eCite Digital Repository

Egg production in the arrow squid Nototodarus gouldi (Cephalopoda : Ommastrephidae), fast and furious or slow and steady?

Citation

McGrath Steer, BL and Jackson, GD, Egg production in the arrow squid Nototodarus gouldi (Cephalopoda : Ommastrephidae), fast and furious or slow and steady?, Marine Biology, 141, (4) pp. 699-706. ISSN 0025-3162 (2002) [Refereed Article]

DOI: doi:10.1007/s00227-002-0864-z

Abstract

The process of reproductive maturation and egg release was examined in the temperate shelf squid Nototodarus gouldi. The energy allocation between somatic and reproductive growth from juvenile to mature adult was investigated throughout the life span to determine the underlying energetic strategy adopted by individuals. The relative weight of the mantle, fin and digestive gland remained unchanged during ovarian development, with no significant correlations found between the mantle length (ML)-gonad residuals and the ML-mantle (r=0.01, P > 0.05), ML-fin (r=0.07, P > 0.05) and ML-digestive gland (r = 0.07, P > 0.05) residuals. This suggested that energy was not being diverted away from somatic growth during sexual development, and consequently neither muscle nor digestive gland was being utilised as an energy store. Since squid in all maturity stages contained some food in their stomachs (e.g. 66.7% of mature animals), it is likely that the cost of maturation in this species is largely being met by food intake. The energy investment in reproductive tissues was relatively low (mean gonado-somatic index for mature individuals was 9.29% ± 0.40%), indicating that only small amounts of energy were being allocated to reproduction at anyone point in time, which is characteristic of a multiple-spawning strategy. Furthermore, oviduct weight was not correlated with body size (r = 0.256, P > 0.05), suggesting that eggs are not stored for a single release. In all except one individual, ovary weight was consistently heavier than oviduct weight, suggesting that the ovary is not being depleted of oocytes as mature ova move into the oviducts. Additionally, the ovaries of mature females contained a range of oocyte sizes with discrete peaks, indicating a continued production and development of oocyte cohorts. The presence of some individuals with stretched empty oviducts is further evidence that the reproductive strategy of N. gouldi is slow and steady, with eggs possibly being released in discrete batches over a period of time.

Item Details

Item Type:Refereed Article
Research Division:Biological Sciences
Research Group:Ecology
Research Field:Marine and Estuarine Ecology (incl. Marine Ichthyology)
Objective Division:Environment
Objective Group:Flora, Fauna and Biodiversity
Objective Field:Marine Flora, Fauna and Biodiversity
Author:McGrath Steer, BL (Mrs Belinda McGrath Steer)
Author:Jackson, GD (Dr George Jackson)
ID Code:26077
Year Published:2002
Web of Science® Times Cited:27
Deposited By:IASOS
Deposited On:2002-08-01
Last Modified:2011-08-02
Downloads:0

Repository Staff Only: item control page