Influence of female age, body size and environmental conditions on annual egg production of the bullhead

Authors: Abdoli, A.1; Pont, D.1; Sagnes, P.1

Source: Journal of Fish Biology, Volume 67, Number 5, October 2005 , pp. 1327-1341(15)

Publisher: Blackwell Publishing

Key:
Free Content - Free Content
New Content - New Content
Subscribed Content - Subscribed Content
Free Trial Content - Free Trial Content

Abstract:

A population of bullhead Cottus gobio inhabiting a mountainous river network, was examined for the influence of maternal condition (total length, LT, and age class in years) and environmental factors (water temperature and fish density) on fecundity, egg size and net annual reproductive effort (ER, defined as the ratio of total egg production mass to body mass) within several stocks. Regardless of location within the drainage network, bullhead reproduction was synchronous, with only a single batch and fecundity ranging from 69 to 896 eggs per female. As with LT fecundity increased with age, although the difference between age classes 5 and 6 years was smaller than between other age classes. Egg diameter also increased with age from age classes 2 to 4 years, but then tended to decrease for age classes 5–6 years. Multiple stepwise regression was used to examine the effect of female LT, water temperature and fish densities on bullhead egg production for each of the four age classes (2, 3, 4 and 5–6 years) separately. When statistically significant, water temperature always had a positive effect and fish densities a negative effect, on fecundity and egg size. The LT always had a positive effect on fecundity for all the age classes. In contrast, LT had a positive effect on egg size and ER only for female reaching maturity (2 years), whereas intermediate aged females (3–4 years) were insensitive and the oldest fish showed a negative response.

Keywords: allocation to reproduction; Cottus gobio; density-dependent; egg size; fecundity; temperature

Document Type: Regular paper

DOI: 10.1111/j.0022-1112.2005.00829.x

Affiliations: 1: CNRS UMR 5023, Ecologie des Hydrosystèmes Fluviaux, Université Lyon 1, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne Cedex, France and

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$49.48 plus tax      Refund Policy

 

OR

Back to top

Key:
Free Content - Free Content
New Content - New Content
Subscribed Content - Subscribed Content
Free Trial Content - Free Trial Content
Share this item with others: These icons link to social bookmarking sites where readers can share and discover new web pages.
Page Help Click here for Page Help
Shopping cart
Tools
Sign in






Need to register?
Sign up here
Text size: A | A | A | A