Recruitment patterns and post-metamorphic attachment by the solitary ascidian, Ciona intestinalis (Linnaeus, 1767) in an invading population from Placentia Bay Newfoundland and Labrador

• Main Author: Reid, Vanessa N.
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2017
• Subjects: Newfoundland
• Online Access: https://research.library.mun.ca/12561/; https://research.library.mun.ca/12561/1/thesis.pdf

Ciona intestinalis (Linneaus, 1767) is a non-indigenous species discovered in Newfoundland (NL) in 2012. It is a bio-fouler with potential to cause environmental distress and economic strain for the aquaculture industry. Key in management of this species is site-specific knowledge of life history and ecology. This study defines the environmental tolerances, recruitment patterns, habitat preferences, and attachment behaviours of C. intestinalis in Newfoundland. Over two years of field work, settlement plates and surveys were used to determine recruitment patterns, which were correlated with environmental data. The recruitment season extended from mid June to late November. Laboratory experiments defined the growth rate and attachment behaviours of Ciona intestinalis. I found mean growth rates of 10.8% length·d⁻¹. The ability for C. intestinalis to undergo metamorphosis before substrate attachment, forming a feeding planktonic juvenile, thus increasing dispersal time was also found. These planktonic juveniles were then able to attach to available substrates post-metamorphosis.