Inshore spawning grounds of the squid Doryteuthis gahi suggest the consistent use of defoliated kelp Lessonia trabeculata in Central Chilean waters
Sergio A. Carrascoa, Alejandro Pérez-Matusa 2015 (subscription)
Sergio A. Carrascoa, Alejandro Pérez-Matusa 2015 (subscription)
ABSTRACT
Coastal spawning grounds of the squid Doryteuthis gahi were identified for the first time at three sites in Central Chile during 2014 and 2015. A total of 15 egg masses were collected from between 10 and 15 m depth and brought to the laboratory for evaluating capsular, embryonic and when possible, paralarval characters. Egg capsules from all spawning areas were similar in size (∼25 mm in length) and number of embryos per capsule (∼15). Egg-laying patterns, in addition to field observations, suggest that relatively small D. gahimay be using shallow waters in semi-protected environments to reproduce and spawn. Additionally, the differential use of healthy versus defoliated kelp Lessonia trabeculatasuggests that egg-laying females selectively choose substrata that limit mechanical damage to the fragile egg capsules and that also allow for adequate water flow, which could be reduced in a mass of kelp fronds. These findings highlight the opportunistic behaviour of D. gahi which use overgrazed L. trabeculata, a condition that is widespread in areas with high herbivory pressure.