Open AccessSize metrics, longevity, and growth rates in Umbellula encrinus (Cnidaria: Pennatulacea) from the eastern Canadian Arctic.
Author(s) -
Bárbara de Moura Neves,
Evan Edinger,
Vonda Hayes,
Brynn M. Devine,
Laura J. Wheeland,
Graham D. Layne
Publication year - 2018
Publication title -
arctic science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.672
H-Index - 4
ISSN - 2368-7460
DOI - 10.1139/as-2018-0009
Subject(s) - longevity , arctic , fishing , bay , annual growth % , growth rate , oceanography , cnidaria , coral , geography , biology , physical geography , ecology , environmental science , geology , geometry , mathematics , genetics , forestry
Umbellula encrinus (Linnaeus, 1758) is a deep-water sea pen commonly found in the eastern Canadian Arctic. It can reach heights of >2 m, and it has often been caught as fishing bycatch. Here, we characterized abundance/density, size metrics, longevity, and growth rates of U. encrinus colonies from Baffin Bay (between Greenland and Canada). No prevalent size classes were identified at most locations, except for Jones Sound and Cape Dyer, where small-size colonies dominated. Average number of growth rings in the internal skeleton (axis) of the examined colonies ranged between 2 and 68, with a maximum of 75. A bomb- 14 C analysis yielded 14 C curves comparable with those of other deep-water octocorals with annual ring formation. A trace element analysis of Mg/Ca, Sr/Ca, Ba/Ca, and Na/Ca yielded values oscillating along the axis radius, with the number of peaks and growth rings being comparable. Growth rates averaged 0.067 ± 0.015 mm year −1 (radial extension) and 4.5 ± 1.2 cm year −1 (linear extension), considering rings to be formed annually. Relationships between radial growth rates, depth, and surface salinity were weak but statistically significant. Umbellula encrinus is a long-lived species, vulnerable to various types of fishing gear, with a skeleton that stores biological and environmental information.