Marie-Josée Abgrall , PhD candidate (2006-)
MS in Marine Biology, University of Central Florida, FL.
BSc in Biology, Laval University, Qc.
PhD Project: Effects of organic matter and hydrogen sulfide on habitat selection behaviour, and resuspension of larvae and post-larvae of the softshell clam Mya arenaria

Dissolved hydrogen sulfide (H₂S) is a constituent of nearly all marine sediments and its production in sediments is normally not detrimental to marine organisms. However, infaunal organisms can be exposed to higher levels as the formation of H₂S in sediments is often correlated with an accumulation of organic matter. Breakdown of H₂S by bacteria can lead to considerable depletion of O₂ in the sediments and therefore, turn the substrata into an unsuitable habitat for larval settlement and early juvenile survival. My PhD project is to determine how detrimental the effects of high H₂S concentrations in the sediments can be for M. arenaria, a commercially important species in New Brunswick, and to determine the overall impact on the species recruitment. The first part of this research project will look at the larval habitat selection and behaviour during substratum exploration prior to settlement, and the minimal H₂S concentration and organic matter concentration needed to induce settlement and post-settlement behavioural modifications in the larvae and post-larvae. Then, the second part will investigate the resuspension rate of larvae and post-larvae at different H₂S and organic matter concentrations. Finally, the third part of this research project will look at the effect of different H₂S and organic matter concentrations on the lipid content of the competent larvae and post-larvae as an indicator of the health and survival potential of the individuals.

In addition of controlled experiments conducted at the Marine Centre in Shippagan, comparative experiments measuring resuspension rates and quantifying population structure will be carried out in the field at various sites along the Northumberland Strait in New Brunswick. This research will provide a better understanding of how sediment geochemistry affects settlement and post-settlement behaviour of shellfish, and underscore the importance of understanding the processes that affect recruitment of benthic marine invertebrates, a fundamental element of population dynamics.

E-mail: Marie-Josee.Abgrall@unb.ca

Stéphan LeBlanc, MSc candidate (2006- )
BSc. (honours) Freshwater Ecology, Université de Moncton (2004)
Project: Impact of scallop dredging on marine habitat and associated fauna.

The scallop fishers use heavy steel drags or dredges that they tow either on the sides or in the back of their fishing vessels. My work focuses on assessing the impact of this fishing gear on different marine habitats (e.g. mud-sand / rocky-reef) and their associated fauna and infauna. Using a BACI (Before-After-Control-Impact) design, we’re doing some experimental fishing with low and high fishing intensities while collecting data with an underwater Troika video system and benthic grab. To asses the ecological resilience of the impact the sampling is done again 3-4 months after the fishing activity. This work is carried out in the Northumberland Strait and in the Baie des Chaleurs, NB.

E-mail:Stephan LeBlanc

Lauren Ellis, MSc. candidate (2009-)
B.Sc. (honours) Biology, Carleton University, Ottawa, Ontario. 2008.
Project: Settlement and biodiversity of marine invertebrates on shallow cobble habitats of the southwest Bay of Fundy: Test of a new monitoring tool and of the decreased-substrate settlement-intensification hypothesis.

My project will focus on identifying the effect of surrounding substrate on settlement and its implications on biodiversity. A new diversity monitoring tool will be used to gather data about juvenile settlement patterns. This will result in a good estimation of the local benthic fauna from shallow muddy and rocky sites in the Bay of Fundy as well as the opportunity to increase the effectiveness of the tool and ease of use. The knowledge gained from this project will facilitate future biodiversity studies using the monitoring tool and shed light on the settlement patterns of select marine invertebrates, thus improving conservation management efforts.

E-mail: Lauren Ellis

Betsy Barber, MSc. Candidate (2010-)
BSc. (honors) Marine Biology, University of Maine at Machias (2009)
Project:  Role of predation as a source of early post-settlement mortality of marine invertebrates in rocky subtidal areas of the southwest Bay of Fundy.

Predation during early post-settlement is thought to be an important process affecting juvenile recruitment.  Variability in recruitment can influence both the distribution and abundance of adults within a community.  Using a new monitoring tool developed to quantify species diversity within a given site, we will determine the effect of predation on the community as a whole as well as on individual species.  This will help further our knowledge on whether predation regulates early post-settlement mortality, and will contribute to management decisions in the southwest Bay of Fundy.

E-mail: Betsy Barber

Biodiversity project coordinator/ Research technician