Sea anemones and brittle stars: unexpected predatory interactions during induced in situ oxygen crises

Autor(en)
Bettina Riedel, Michael Stachowitsch, Martin Zuschin
Abstrakt

During oxygen crises, benthic faunas exhibit a series of behavioural patterns that reflect the duration and severity of the event. During artificially induced oxygen deficiencies at 24 m depth in the Northern Adriatic Sea, we photographically documented predation by the sea anemones Cereus pedunculatus (Pennant, 1777) and Calliactis parasitica (Couch, 1842) on the brittle star Ophiothris quinguemaculata (DelleChiaje, 1828). Five predatory events were recorded with four anemones during nine deployments totalling 817 h of observation. Under near-anoxic conditions, individuals of both actinians made contact with, pulled in and consumed the brittle stars. The duration of each predatory event was 1.5-7.5 h. In three of the five events, bittle star remains were regurgitated after an additional 2.0-12,5 h of degestion by the anemones. Our time-lapse sequences demonstrate that oxygen deficiency, beyond eliciting a series of specific behaviours in members of ech species, also promotes previously unobserved interspecific interactions. Our results show that sea anemones are not only highly resistant to anoxia, but may also benefit by taking advantage of prey that are more vulnerable to anoxic conditions.

Organisation(en)
Institut für Paläontologie
Journal
Marine Biology: international journal on life in oceans and coastal waters
Band
153
Seiten
1075-1085
Anzahl der Seiten
10
ISSN
0025-3162
DOI
https://doi.org/10.1007/s00227-007-0880-0
Publikationsdatum
2008
ÖFOS 2012
105118 Paläontologie
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/25f60a8c-b0fb-4922-9932-6b30a807153b