Annis E.R.,Hood College |
Yund P.O.,University of New England at Biddeford |
Yund P.O.,Downeast Institute
Canadian Journal of Fisheries and Aquatic Sciences | Year: 2013
We examined the potential for bottom temperatures ≤12 °C to inhibit successful recruitment of planktonic lobster postlarvae to the benthos. In laboratory trials, postlarvae held at 11 °C exhibited higher mortality, slower development, and reduced size increase at molt relative to postlarvae held at 13 °C. We sampled at field sites within Machias Bay, Maine (mean bottom temperature 12.39 °C, 46.1 degree-days ≥12 °C) and at the mouth of the bay (mean bottom temperature 11.57 °C, 5.1 degree-days ≥12 °C), where temperature was influenced by the cold Eastern Maine Coastal Current (EMCC). We found significantly higher settlement at the warm inshore site but, the abundance of competent planktonic postlarvae was not significantly different between sites, indicating a disconnect between postlarval abundance and settlement. Regional sampling of newly settled lobsters revealed a pattern of higher settlement at inshore sites extending across a broader coastal region impacted by the EMCC. Our results suggest that small differences in water temperature may shape settlement patterns through either behavioral avoidance of colder settlement sites or elevated postsettlement mortality of postlarvae settling at colder sites.
Helmuth B.,Northeastern University |
Choi F.,Northeastern University |
Matzelle A.,Northeastern University |
Torossian J.L.,Northeastern University |
And 59 more authors.
Scientific Data | Year: 2016
At a proximal level, the physiological impacts of global climate change on ectothermic organisms are manifest as changes in body temperatures. Especially for plants and animals exposed to direct solar radiation, body temperatures can be substantially different from air temperatures. We deployed biomimetic sensors that approximate the thermal characteristics of intertidal mussels at 71 sites worldwide, from 1998-present. Loggers recorded temperatures at 10-30 min intervals nearly continuously at multiple intertidal elevations. Comparisons against direct measurements of mussel tissue temperature indicated errors of ∼2.0-2.5 °C, during daily fluctuations that often exceeded 15°-20 °C. Geographic patterns in thermal stress based on biomimetic logger measurements were generally far more complex than anticipated based only on 'habitat-level' measurements of air or sea surface temperature. This unique data set provides an opportunity to link physiological measurements with spatially-and temporally-explicit field observations of body temperature. © 2016 The Author(s).
News Article | December 15, 2015
Blue mussels, Mytilus edulis, live on northern Atlantic shores in the area between high and low tides. "Mussels are one of the most significant filter-feeders in the marine environment," said Brian Beal, a marine ecologist at the University of Maine at Machias. "They are responsible not only for efficiently producing high-quality protein but for cleaning the waters around them through their feeding activities." Because many creatures--especially humans--enjoy eating blue mussels, farmers grow mussels using aquaculture, or aquatic farming. Beal, along with a team of NSF-funded researchers at the University of Maine at Machias and the Downeast Institute, is investigating the growing conditions and practices that will reliably yield healthy and plentiful blue mussels. The researchers also are investigating exactly when to transition the young mussels into ocean pens, and where in the pens they grow best. Find out more in this discovery. Credit: Brian Beal, University of Maine at Machias, Division of Environmental and Biological Sciences These tiny creatures are Arctic surfclams. They're getting packed up for a trip to the shore. With some help, they're about to take up residence in an intertidal mudflat on the Maine coast, or 'Downeast' as they say around here, referring to ships sailing centuries ago from Boston east to Maine and downwind. The area's rich maritime history is not lost on Brian Beal, a marine ecologist with the University of Maine at Machias who has lived here all of his life and grew up working on the water. With support from the National Science Foundation (NSF), Beal and a team based at the university's Marine Science Field Station at the Downeast Institute are putting their aquaculture innovation skills to work. The team's goals are to diversify the U.S. market for shellfish and increase the number of jobs in that market. The researchers are focused on two types of shellfish with the potential to bring more jobs and dollars to the area: blue mussels and Arctic surfclams. In the case of the latter, Arctic surfclams are not only a valuable species, but, Beal says, no one has ever tackled culturing them before. Arctic surfclams are a deepwater species that range from Rhode Island north to Newfoundland. Low densities have so far prevented the species from becoming a highly valued fishery in the U.S., but in Canada, there's a $50 million fishery off the southeast coast of Halifax, Nova Scotia, and off the Grand Banks, south of Newfoundland. The other species, blue mussels, aren't new to Maine. They've been a part of the seafood industry here for years. Beal would like to expand the market for blue mussels by making cultivation more of a turnkey operation by providing mussel growers with a choice between collecting wild seed (that depends each year on the vagaries of nature) and a more consistent hatchery-reared seedling. This is a Partnerships for Innovation: Building Innovation Capacity (PFI: BIC) project, which is focused on examining opportunities to create new marine aquaculture jobs in coastal Maine through shellfish research. The broader impacts of this research are related to increasing U.S. competitiveness in the seafood industry. "This NSF PFI project embodies a quintessential combination of science, engineering, technology, education, outreach and the pursuit of innovation," says Sara Nerlove, program director for the PFI: BIC program. "And because Brian Beal was born and raised in the area, we have a special research situation, one in which he's been able to capitalize on his thorough knowledge of the people and the local economy." Explore further: Key discovery made in war on sea lice infestations
Wilkinson E.B.,University of New England at Biddeford |
Grabowski J.H.,Northeastern University |
Sherwood G.D.,Gulf of Maine Research Institute |
Yund P.O.,Downeast Institute
Journal of Experimental Marine Biology and Ecology | Year: 2015
The American lobster, Homarus americanus, is an important benthic consumer in the Gulf of Maine and supports an extremely valuable fishery in New England and eastern Canada. Meanwhile, there is substantial interest in restoring large predator fish species to the Gulf of Maine, and these predators may impact lobster populations both by consuming them and by inducing them to alter their behavior. Lobster tethering experiments were used to examine the susceptibility of a range of lobster size classes to predation in Saco Bay, Maine. The most susceptible sizes of lobsters were then exposed to three different fish predators (Atlantic striped bass Morone saxatilis, Atlantic cod Gadus morhua, and sea raven Hemitripterus americanus) separately in experimental mesocosm tanks. Juvenile lobsters moved less and spent more time in shelter when in the presence of cod or sea raven. By contrast, striped bass did not induce lobsters to alter their behavior. Striped bass are highly mobile, active pursuit predators, which are thought to induce weaker behavioral responses in prey than sit-and-pursue predators like sea ravens. Thus, differences in lobster sheltering behavior corresponded with differences in predator foraging behavior. These predator-induced changes in behavior can result in less foraging activity, which may translate into reduced lobster growth and reproduction. Efforts to model marine communities and ecosystems will benefit from a more holistic understanding of whether predators induced prey to modify their foraging behavior and habitat usage. © 2015 Elsevier B.V.
Thomas F.I.M.,Hawaii Institute of Marine Biology |
Kregting L.T.,Hawaii Institute of Marine Biology |
Kregting L.T.,University of New England at Biddeford |
Badgley B.D.,University of South Florida |
And 4 more authors.
Marine Ecology Progress Series | Year: 2013
ABSTRACT: Fertilization efficiency in free-spawning invertebrates in the marine environment depends on the complex interaction between biological and physical factors. Experimental evidence indicates that in some taxa, a considerable amount of fertilization may take place on the substrate and within flow structures in close proximity to a spawning female. Gametes can be retained on a spawning animal, resulting in their slow release over relatively long periods of time, and retained eggs can be fertilized before they are released into the water column. Hydrodynamic conditions are likely to influence both the retention of gametes and their subsequent mixing in the water column as well as the relative importance of fertilization in the water column and in other locations near spawning animals. Here, fertilization in the broadcast-spawning sea urchin Strongy - locentrotus droebachiensis was explored over a range of flow velocities (u = 2 to 15 cm s-1) to determine the effect of velocity on fertilization and the relative contribution of different locations (aboral surface of the female, water column, wake, and the substrate behind the female) to overall fertilization. As velocity increased, the percentage of eggs fertilized declined in all locations. At all velocities, more eggs were fertilized on the aboral surface than in the water column. Further, as velocity increased, the relative contribution of the aboral surface to overall fertilization increased. These results highlight the importance of considering the interaction of hydrodynamics, organism morphology, and gamete properties in studies of fertilization in broadcast-spawning invertebrates.© Inter-Research 2013. www.int-res.com.
Wallace C.C.,University of New England at Biddeford |
Wallace C.C.,IDEXX Laboratories |
Yund P.O.,University of New England at Biddeford |
Yund P.O.,Downeast Institute |
And 4 more authors.
EcoHealth | Year: 2013
Studies on marine mammals can inform our understanding of the environmental health of the ocean. To evaluate the potential for changes in antimicrobial resistance, we analyzed a database spanning 2004-2010 that consisted of bacterial isolate identity and antimicrobial sensitivity for stranded pinnipeds in the Northwest Atlantic. Samples (n = 170) from treated animals yielded 310 bacterial isolates representing 24 taxa. We evaluated changes in antimicrobial class resistance from 2004 to 2010 for eight taxa. Escherichia coli displayed a significant increase in resistance to several antimicrobial classes. Other taxa displayed significant increases in resistance to aminoglycosides, and/or fluoroquinolones. In addition, we observed a significant increase in multiple antimicrobial resistance in cultures from untreated animals. These results demonstrate an increase in resistance among common bacterial pathogens of marine mammals over a time span of 6 years. © 2013 International Association for Ecology and Health.