1. Innovative Tools for Student Research
Shaun M. Gill, Tim Arienti, Troy Thibeau
University of New England Marine Science Center, a UNE Center of Excellence
Variable Speed Crustacean Treadmill ‘11
Tide Simulation Systems ‘09
Flow Through Seawater Chiller ‘13
Oscillating Salinity System ‘10
The flow-through water chiller is a portable by-catch holding system made for installation on
commercial vessels fishing the North Atlantic. It was purpose built to hold deep water by-catch
specimens in a temperature controlled environment for up to 48 hours. Insulated commercial
totes hold chilled seawater and house custom bent stainless steel coils which act as heat
exchangers when submerged in an ice water slurry. The system is capable of chilling and
maintaining water to within +/-1°C of bottom water temperature. Extreme differences between
bottom water and deck conditions post-capture can be extremely stressful to by-catch. This system
minimizes on-deck stresses, allowing for unprecedented direct observation of by-catch and
understanding post-capture mortality rates of commercially important species.
The system was a team design lead by graduate student Ryan Knotek ’15 in collaboration with the
New England Aquarium and Virginia Institute of Marine Science. The system helps the Sulikowski
Lab understand the impacts of commercial fishing on by-catch, which is critical for making
informed decisions about managing commercially important fish stocks.
Knotek and his teammates were mentored in tool-use and prototype fabrication. The team built all
system components including the heat exchange coils and water distribution systems. They
learned how to fabricate as well as understand the design and function of each component they
created. The chilled water system and the science behind it were showcased in Commercial
Fisheries News, September 2013, Vol 41, No 1.
This two-tiered tank system uses digitally controlled ball
valves to strategically drain and fill tanks synchronized
with natural tidal intervals. Salinity is diluted and re-
concentrated as it would be in natural tidal estuaries. Both
tiers of the system are flow-through, requiring only gravity
and head pressure to move water. Ambient water baths
ensure temperature control and stand pipes regulate water
volume. Seawater is precisely mixed with freshwater to
create custom salinity profiles that shift with daily high and
low tide intervals.
The oscillating salinity system was designed for graduate
and undergraduate research in the Frederich lab. The
students operate and maintain system and have been
collecting publishable data with it since 2010.
Creating estuarine conditions in the lab synchronized to
local conditions with local seawater maximizes similarity
to in situ environmental conditions. In this particular
instance, salinity parameters are altered to induce
physiological stresses in the invasive green crab, Carcinus
maenas . The stresses simulate conditions the crabs might
experience might experience when living at estuary
extremes. When used in conjunction with the crab
treadmill, researchers can compare the effects of stress on
physiological performance which is administered in the
form of treadmill exercise. This research helps the
Frederich lab understand how C. maenas has adapted to
living in rapidly changing environments and also helps
describe the molecular physiology involved during
different molt stages.
The crab treadmill is a reverse engineering project inspired by the semi-infamous YouTube
sensation “Shrimp on a Treadmill”. Except for the hardware and the brushless motor, all
parts for this project were fabricated using manual machining equipment and a table saw.
The project represents approximately 100 hours of build time and many more hours of
rendering and design research. Quick disconnect fittings allow easy plumbing to a peristaltic
pump that recirculates modified seawater throughout the chamber.
The treadmill was built for Dr. Markus Frederich and his students to study the physiology of
the invasive green crab, Carcinus maenas. Carcinus were introduced to US waters in the
1800’s, arriving on European trading ships. Carcinus rapidly outcompete North American
species and decimate ecologically and economically important species such as the soft
shelled clam (aka Steamers).
The treadmill helps the Frederich Lab study marine invertebrate regulation of energy
metabolism under stress. Understanding invasive species physiology helps predict how far
the crabs can spread within an ecosystem and as well as how they compete with native
species. The treadmill induces exercise, a form of stress, which manipulates crab
physiology of under different treatment regimes.
Carcinus maenas, appears in red and green color morphs. The Frederich lab investigates
potential differences between these two color morphs by exposing them to stressors like
hypoxia (low levels of oxygen available) and tests the animals’ performance. By forcing the
animals to run underwater on the treadmill after exposing them to different time periods
of hypoxia, red morphs’ running endurance decreases faster than their green
counterpart’s. Whether this difference is reflected in ecological success or in molecular and
genetic parameters is currently being investigated.
Scan this QR code with a mobile device to see the treadmill video on YouTube!
Green crabs, Carcinus maenas, exposed to these
oscillating salinity conditions are affected by decreasing
and increasing ion concentrations in their hemolymph
(blood). The Frederich lab investigates resulting
changes in the ion regulatory machinery at the
molecular and genetic level. First results indicate that
these oscillating salinity conditions pose less energetic
stress that an exposure to continuously low salinity
Salinity profile in the oscillating tank with alternating 6
hours of regular strength sea water (32 ppt) and 6 hours of
low salinity sea water (13 ppt), simulating a typical tidal
cycle.
Salt marshes and the critical ecosystem services that they provide - such as water
filtration, or as a nursery ground for fishes – are at risk due to predicted rises in sea level
associated with global warming. Salt marsh persistence in the face of sea-level rise will
be determined, in part, by the balance between plant production which helps build salt
marshes, and decomposition by microbes which reduces marsh elevation. Students from
the Zogg and Travis labs have been examining these processes for several years, using
both outdoor and indoor tide simulation systems.
(Right) An outdoor tidal simulation system was created by plumbing 5’ diameter
fiberglass tanks with actuated ball valves controlled by timers. This allowed researchers
to regulate when and for how long the tanks were flooded, so that they could simulate
sea level rise due to global warming. This outdoor system takes advantage of natural
sunlight, which allows scientists to work with photosynthetic organisms, such as salt
marsh plants
(Bottom) A scaled down version of the tidal simulation system was constructed inside
the MSC to study effects of sea level rise on processes that do not require sunlight, such
as the activity of microbes in salt marsh sediments.
Sean Balschi ‘14
Anthony Himes ‘14
Kate DiVito ‘11
Anthony Himes ‘14
Ryan Knotek ‘15
Connor Capizzano ‘15 Liese Carleton ‘ 14
Joe Langan ‘ 15
Ryan Knotek ‘15
Liese Carleton ‘ 14
Joe Langan ‘ 15 Ryan Knotek ‘15 Ryan Knotek ‘15
Connor Capizzano ‘15