Advances in tagging syngnathids, with the effects of dummy tags on behaviour of Hippocampus guttulatus

Publication Type: Journal Article

Year of Publication: 2011

Authors: Caldwell, IR, Correia M, Palma J, Vincent ACJ

Journal: Journal of Fish Biology

Volume: 78

Issue: 6

Pagination: 1769–1785

Date Published: 04/2011

Keywords: acoustic telemetry, Aquarium, Hippocampus, movement, seahorse, visible implant elastomer,welfare


Artificial marking and tagging techniques have been used to study movement, population dynamics, behaviour, ecology, survival and growth of at least 25 syngnathid species. External necklace-style tags and injection of visible implant elastomer have been the most used techniques, uniquely identifying hundreds of individual syngnathids to study population dynamics, mortality, behaviour, ecology and growth in at least 13 and 12 species, respectively. Only two studies, both on larger syngnathid species, have tested the use of internal or electronic tags. This new case study reveals that dummy tags, weighing up to 6% of individual body mass, have minimal effect on normal ex situ behaviour of the long-snouted seahorse Hippocampus guttulatus, a smaller syngnathid. In paired aquarium trials, tags did not affect movement, holdfast use or general behavioural state, and only had a short-term effect (1 day) on vertical orientation. Tagged H. guttulatus gained more mass during the 5 day trials, a result which warrants further exploration but indicates that tags did not reduce feeding. This study shows promise for using electronic tagging to study H. guttulatus and similarly sized syngnathids in the wild.

DOI: 10.1111/j.1095-8649.2011.02983.x