Reproductive ecology of the Antarctic brachiopod Liothyrella uva

The aim of this research project was to investigate ecological aspects of reproduction in the Antarctic brachiopod Liothyrella uva (Broderip, 1833). Previous studies on L. uva revealed a low metabolism, slow growth and longevity which, coupled with the recent discovery of sub-biennial growth rings,...

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Main Author: Meidlinger, Karen
Format: Thesis
Language:English
Published: University of Southampton 1997
Subjects:
Online Access:https://eprints.soton.ac.uk/462997/
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spelling ftsouthampton:oai:eprints.soton.ac.uk:462997 2023-07-30T03:58:33+02:00 Reproductive ecology of the Antarctic brachiopod Liothyrella uva Meidlinger, Karen 1997 https://eprints.soton.ac.uk/462997/ English eng University of Southampton Meidlinger, Karen (1997) Reproductive ecology of the Antarctic brachiopod Liothyrella uva. University of Southampton, Doctoral Thesis. Thesis NonPeerReviewed 1997 ftsouthampton 2023-07-09T22:51:06Z The aim of this research project was to investigate ecological aspects of reproduction in the Antarctic brachiopod Liothyrella uva (Broderip, 1833). Previous studies on L. uva revealed a low metabolism, slow growth and longevity which, coupled with the recent discovery of sub-biennial growth rings, indicates the possibility of an unusual reproductive strategy. The reproductive cycle of L. uva is described, based on gonad section data from monthly samples collected from a population at Signy Island, Antarctica. Mean oocyte diameter (102-156μm) and the mean percent spermatozoa (27-50%) changes over a two-year period, show large inter-annual differences in reproductive activity. These data also highlight the variability of the reproductive cycle of L. uva and suggest the possibility of three reproductive cycle periodicities (continuous, annual and long-term). Brooding in L. uva was investigated in the austral summer. Brood characteristics measured included the number in each brood, size of embryo or larva, total energy content of the whole brood, energy content per gram dry mass, and energy per embryo or larva. Elemental (CHN) analysis enabled energies to be calculated from carbon values and were also obtained for the brooding female tissues. Brood energy content decreased significantly (from 49-40kJ/gDM) over the three-month period. However, energy per embryo or larva significantly increased (from 0.15J to levels around 0.40J). This was a result of the addition of new, small, highly energy dense early embryos later in the main brooding period. Larval release was studied by holding L. uva females in individual tanks. Release types and timing were highly variable both for individual L. uva and between females. Overall, the period of larval release of each female varied between less than 1 week to over 1.5 months. All developmental stages were seen from early gastrulae through to settled juveniles. Settlement in the laboratory matched that seen in a concurrent field experiment. Larvae exhibited preference for live ... Thesis Antarc* Antarctic Antarctica Signy Island University of Southampton: e-Prints Soton Antarctic The Antarctic Austral Signy Island ENVELOPE(-45.595,-45.595,-60.708,-60.708)
institution Open Polar
collection University of Southampton: e-Prints Soton
op_collection_id ftsouthampton
language English
description The aim of this research project was to investigate ecological aspects of reproduction in the Antarctic brachiopod Liothyrella uva (Broderip, 1833). Previous studies on L. uva revealed a low metabolism, slow growth and longevity which, coupled with the recent discovery of sub-biennial growth rings, indicates the possibility of an unusual reproductive strategy. The reproductive cycle of L. uva is described, based on gonad section data from monthly samples collected from a population at Signy Island, Antarctica. Mean oocyte diameter (102-156μm) and the mean percent spermatozoa (27-50%) changes over a two-year period, show large inter-annual differences in reproductive activity. These data also highlight the variability of the reproductive cycle of L. uva and suggest the possibility of three reproductive cycle periodicities (continuous, annual and long-term). Brooding in L. uva was investigated in the austral summer. Brood characteristics measured included the number in each brood, size of embryo or larva, total energy content of the whole brood, energy content per gram dry mass, and energy per embryo or larva. Elemental (CHN) analysis enabled energies to be calculated from carbon values and were also obtained for the brooding female tissues. Brood energy content decreased significantly (from 49-40kJ/gDM) over the three-month period. However, energy per embryo or larva significantly increased (from 0.15J to levels around 0.40J). This was a result of the addition of new, small, highly energy dense early embryos later in the main brooding period. Larval release was studied by holding L. uva females in individual tanks. Release types and timing were highly variable both for individual L. uva and between females. Overall, the period of larval release of each female varied between less than 1 week to over 1.5 months. All developmental stages were seen from early gastrulae through to settled juveniles. Settlement in the laboratory matched that seen in a concurrent field experiment. Larvae exhibited preference for live ...
format Thesis
author Meidlinger, Karen
spellingShingle Meidlinger, Karen
Reproductive ecology of the Antarctic brachiopod Liothyrella uva
author_facet Meidlinger, Karen
author_sort Meidlinger, Karen
title Reproductive ecology of the Antarctic brachiopod Liothyrella uva
title_short Reproductive ecology of the Antarctic brachiopod Liothyrella uva
title_full Reproductive ecology of the Antarctic brachiopod Liothyrella uva
title_fullStr Reproductive ecology of the Antarctic brachiopod Liothyrella uva
title_full_unstemmed Reproductive ecology of the Antarctic brachiopod Liothyrella uva
title_sort reproductive ecology of the antarctic brachiopod liothyrella uva
publisher University of Southampton
publishDate 1997
url https://eprints.soton.ac.uk/462997/
long_lat ENVELOPE(-45.595,-45.595,-60.708,-60.708)
geographic Antarctic
The Antarctic
Austral
Signy Island
geographic_facet Antarctic
The Antarctic
Austral
Signy Island
genre Antarc*
Antarctic
Antarctica
Signy Island
genre_facet Antarc*
Antarctic
Antarctica
Signy Island
op_relation Meidlinger, Karen (1997) Reproductive ecology of the Antarctic brachiopod Liothyrella uva. University of Southampton, Doctoral Thesis.
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