As ocean temperatures increase, crustaceans become subjected to more immediate, microecological impacts because of their exothermically-driven growth and development. In this laboratory-based study, ovigerous American lobster were allowed to incubate their eggs for either a normal period of time (7–9 months including time at temperatures <10C), or were held in water >10C to speed up the rate of egg development (4–6 months). Females that had shorter incubation times had longer periods of larval release compared with females that incubated eggs for a normal period of time. Females incubating eggs for a shorter period of time also produced more larvae, and this was explained by the daily loss of a small number of eggs. Subsequent modeling of the relationship between dates of egg extrusion and hatching using data compiled from Massachusetts Bay demonstrated that there was a critical period in the fall at which larval development would switch from a resultant hatch in the spring to a hatch in the late fall or winter. The short-term implications of global warming on egg development and hatching in lobsters is discussed, including the production of larvae at suboptimal times of the year, as well as a temporal change in the abundance of larvae during the hatching season. Either of these events can lead to an increase in larval mortality and hence a decrease in population productivity.
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The research involves rearing of larvae under controlled pH conditions until settlement age. Otoliths (3 on each side of the head of the fish) are removed and imaged by scanning electron microscopy. Images are then analyzed for morphometrics (shape and size), mineral habit and mineral composition.
This research is a partnership with Roger Williams University (Dr. Andrew Rhyne), and UMass Boston (Dr. Robyn Hannigan) and is funded by the National Science Foundation (NSF-CRI-OA 1220480). Students involved in this project include former PhD student Eric Wilcox-Freeburg (PhD 2014, Post-doctoral Investigator, Pacific Northwest National Laboratory) and current PhD student Robert Holmberg.
This research is a partnership with Roger Williams University (Dr. Andrew Rhyne), and UMass Boston (Dr. Robyn Hannigan) and is funded by the National Science Foundation (NSF-CRI-OA 1220480). Students involved in this project include former PhD student Eric Wilcox-Freeburg (PhD 2014, Post-doctoral Investigator, Pacific Northwest National Laboratory) and current PhD student Robert Holmberg.
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Cuticular mineralization in decapods is generally considered to be accomplished from the epidermal side of the cuticle after ecdysis, buffered from the open ocean by the animal’s internal milieu. Thus, only when environmental conditions effectively alter the animal’s internal state will there likely be a resultant effect on mineralization and follow-on effects respective to the lobster’s interaction with chitin degrading bacteria. Therefore, we propose to examine ocean acidification effects on American lobsters under a more complete suite of multiple stressors. We will examine larval life stages and the transition to early benthic juveniles, a life history stage that is subject to OA and environmental impacts because of their fast growth, andsmall body size.