by Erich Luening

May 30, 2017

There’s a lot of research going into rearing bluefin tuna in European countries along the Mediterranean coast, and in Australia and Japan but now researchers in the U.S. state of Maryland are cranking up investigation into this highly valued species.

         Located on Baltimore’s inner harbor on the Chesapeake Bay the University of Maryland Baltimore County's Aquaculture Research Center (ARC) has been studying the bluefin tuna (BFT) life-cycle from egg, larvae and fingerling stage for a number of years while also researching similar life stages of European sea bream and sea bass.

         Professor Yonathan Zohar is chair of the Department of Marine Biotechnology and head of the team at the marine recirculation aquaculture facility: "ARC is a totally contained, fully recirculating, bio-secure marine aquaculture operation. It is fully computer-controlled to allow a wide range of environmental conditions - salinity: 0-to-full seawater, temperature:12-28 degrees C and photoperiod control over individual tanks with simulating sunrise and sunset," conditions, he explained.

Generic facility

         Under Zohar's design, the facility is also very simple in its approach to rearing marine fish and shellfish in a recirculating system.

         "It is a generic facility that can accommodate any fish/shellfish species, tailoring the conditions to allow optimal performance," he says. "We start with city water, run it through activated carbon filters and then make our artificial seawater fully simulating the composition of the marine environment."

         The facility uses unique nitrification and denitrification biofilters to treat the dissolved waste and it also biologically converts the organic/solid waste/sludge to fuel grade methane (natural gas).

         "Therefore, while biologically removing our waste, we generate bio-energy to offset some of the energy costs of the operation," said Zohar. "ARC’s main objectives are to enable our scientists to carry out their aquaculture R&D program on their species of interest in optimal conditions as well as study in a prototype of a fully contained, zero discharge marine aquaculture operation."

Applied research

          Research programs at ARC cover a broad range of topics, including broodstock management and year-round spawning, larval rearing and hatchery technology, food chain and live feeds, reproduction (spawning induction as well as reproductive sterility), growth, environmentally responsible feeds, pathobiology and understanding and overcoming disease.

         There's also a major focus on developing and optimizing environmentally sustainable and economically feasible, bio-secure marine recirculating systems for both hatchery and grow-out production.

         "We work with commercially important finfish such as gilthead sea bream, European sea bass, striped bass, bluefin tuna, Atlantic salmon, rainbow trout, cobia, amberjack and tilapia as well as with blue crab and oysters," Zohar explained. "We run several industry-funded projects to address major challenges in the aquaculture industry, such as closing life cycles of new species, year-round spawning, larval rearing, producing reproductively sterile fish, and improving land-based mariculture."