Journal
<p>Within the English Channel, the common cuttlefish <em>Sepia officinalis</em> is a semelparous species for which a 2-year life cycle was<br />
exclusively described in the 1980s. In the 1990s, new research indicated that whilst a 2-year life cycle was still evident for<br />
females and the large majority of males, a small proportion of males were actually maturing at only 1 year of age. Since<br />
1980, the interest of French and UK fishers for this resource has increased and it is nowadays one of the most important<br />
demersal species of the area and is considered to be fully exploited. From the start of the 20th century, fishing effort<br />
and sea surface temperatures have increased in the English Channel and have probably impacted the life history traits of<br />
<em>S. officinalis</em>. A 2-year sampling programme was undertaken at French landing sites of the English Channel during the reproduction<br />
season in 2010 and 2011 to estimate if the proportion of 1-year-old mature animals has changed. Age determination<br />
was carried out by coupling polymodal decomposition and lipofuscin measurement. Size-at-maturity for each year and each<br />
sex was estimated by fitting a binomial error GLM. Results highlight that a variable percentage of males and females belonging<br />
to the first cohort are mature and that size-at-maturity was lower than that observed in the 1990s. Finally, different parameters,<br />
such as temperature and fishing pressure are explored to discuss changes in life history traits suggesting that cuttlefish<br />
could be an indicator of the temperature regime shift in the English Channel.</p>
