Postgraduate Research Opportunity: MSc
Ref:
AGE
Project Title:
Direct age determination for crustacean fisheries in Ireland
Project Description: The age of fish and shellfish can often be estimated from marks left in scales,
otoliths, vertebrae and shells as a result of growth processes (Meunier, 1988). Managing fisheries
for these species at sustainable levels requires the collection of individual and collective life history
information. Such information enables the assessment of abundance and productivity for fished
species. Determination of age greatly improves the accuracy of these assessments by directly
allowing estimation of the age of sexual maturity, longevity, mortality, reproductive rates and
growth rates. Improvements in the accuracy of age estimation consequently increase confidence in
stock assessments and provide a basis for predicting the resilience of fisheries to exploitation
(Officer, 1995).
Until recently the age and growth of crustacea could only be approximated. Crustacea do not have
bones, scales or vertebrae. Unlike shellfish, crustaceans molt and replace their exoskeleton
frequently during their lives. Therefore, they were not thought to retain permanent structures in
which growth bands are formed and recorded. The recent discovery of a method to directly
determine the age of crustaceans (Kilada et al. 2012) turns that hypothesis on its head, and opens
new possibilities for more accurate stock assessment of crustaceans. Kilada et al. (2012) found that
the base of the eyestalk and a small grinding organ in the stomach (the gastrolith) were retained
during molts. Microscopic examination of thin sections of eyestalks and gastroliths from lobsters,
crabs and shrimp revealed visible growth bands.
These new methods are yet to be proven in the prawn, crab and lobster species native to Ireland.
This project will evaluate whether age can be determined directly for crustacean species of
commercial importance to Ireland. The primary task will be to identify growth-related bands in
local species and use these to determine the age composition of crustacean populations.
The candidate will work closely with commercial fishers and fishery scientists to ensure that the
project outcomes can be adopted in management. The second phase will apply the results to various
populations of prawns to determine population specific age compositions, longevity and rates of
growth and mortality. The relationship between these characteristics and biological and
environmental drivers (such as population density and habitat quality) will be examined.
The candidate will be expected to publish journal papers on crustacean age and growth, and to
apply this knowledge in publications that address the assessment and management needs of Irish
crustacean fisheries.
References:
Meunier FJ (1988). Détermination de l'âge individuel chez les Ostéichthyens à l'aide de la squelettochronologie:
historique et méthodologie. Acta Oecologica / Oecologica Generalis 9, 299-329.
Officer, RA (1995). Vertebral mineralisation patterns in gummy and school sharks and their utility for age
determination. PhD Thesis, University of Melbourne. 300 p.
Kilada R, Sainte-Marie B, Rochette R, Davis N, Vanier C & Campana S (2012). Direct determination of age in shrimps,
crabs, and lobsters. Canadian Journal of Fisheries and Aquatic Sciences, 69(11): 1728-1733.
Research Environment: The successful candidate will join a dynamic group of researchers at the
Marine and Freshwater Research Centre at GMIT. The candidate will have access to state of the art
equipment and facilities. They will benefit greatly from international collaboration through
involvement with experts and stakeholders in groups studying crustacean fisheries biology. The
research project will be co supervised by the Marine Institute.
Requirements/Qualifications: Interested candidates should hold an Honours Degree (minimum 2.2, but
2.1 or higher is desirable) in a cognate discipline e.g. Fisheries, Marine Biology, Ecology or a related
discipline. Candidates should possess excellent technical and laboratory skills (particularly in
microscopy and histology) as demonstrated by their undergraduate qualification, previous research
projects or work experience. A good knowledge of fisheries management and experience in the study of
age and growth are desirable.
Project Duration: 2 years
Conditions:

€16,000 Stipend per annum.

The successful candidate will also gain experience of supporting undergraduate teaching and
learning activities.

Postgraduate fees for EU students will be covered by the project. In addition travel and
consumables costs incurred during the project will be funded.
Please Note: Candidates from outside the EU are eligible to apply, but may be expected to provide
evidence of sources of additional funds to cover excesses associated with Non-EU fees.
Expected Project Start Date: November 2013
Scholarship Application Procedure:
Applicants should submit their curriculum vitae and a personal statement.
The personal statement should be divided into two sections:
1. The first section should:
a) Explain why you have chosen to pursue an MSc research program (in general terms,
without reference to this project), and,
b) Demonstrate the qualities/skills that you have which equip you for undertaking an MSc
research program (in general terms, without reference to this project).
2. In the second section:
c) Outline how your previous experience and academic background make you a suitable
candidate for this particular project.
Application Closing Date: Friday, 11th October 2013 at 12.p.m.
Please email your Curriculum Vitae and Personal Statement to: ResearchOffice@gmit.ie
Applications must be submitted to this e-mail address only.
For further information on the project please contact: Dr. Rick Officer at rick.officer@gmit.ie and Dr. Ian
O’Connor at ian.oconnor@gmit.ie.