Regarding Newlands, N.K., Lutcavage, M.E., Pitcher, T.J. (2006) Atlantic bluefin tuna in the Gulf of Maine, I: Estimation of seasonal abundance accounting for movement, school and school-aggregation behaviour. Environmental Biology of Fishes 77:177–195 Newlands, N.K., Lutcavage, M.E., Pitcher, T.J. (2007) Atlantic bluefin tuna in the Gulf of Maine, II: precision of sampling designs in estimating seasonal abundance accounting for tuna behaviour. Environmental Biology of Fishes 78:000–000

Identifying the origin of fish contained in a mixed fishery is critical for accurate stock assessments and the subsequent development of appropriate management strategies. Using a panel of 92 SNPs developed to differentiate Atlantic bluefin tuna (Thunnus thynnus) from the two main spawning areas (Gulf of Mexico and Mediterranean Sea), we used individual assignment to determine composition of feeding aggregations in the northwestern Atlantic Ocean (Gulf of Maine, Bay of Fundy, Scotian Shelf, Gulf of St. Lawrence, coastal Newfoundland). Among the 3,163 individuals collected between 2004 and 2018, we found that among lower age groups (<15 years) the spawning stock providing the most recruits to the Canadian fishery transitioned from Western Atlantic to Mediterranean origin over time. While the majority of older adults (>15 years) have consistently been of Western Atlantic origin, the disparity in the proportional contribution of western and eastern spawning groups narrowed significantly over the 14-year study period. Our results can be used to inform population-specific exploitation rates, improve stock assessments, identify age-dependent habitat use and areas suitable for additional conservation efforts.

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Diet and condition of Atlantic bluefin tuna (Thunnus thynnus) in the Gulf of Maine, 2004–2008

Environmental Biology of Fishes ◽

10.1007/s10641-014-0368-y ◽

2014 ◽

Vol 98 (5) ◽

pp. 1411-1430 ◽

Cited By ~ 21

Author(s):

John M. Logan ◽

Walter J. Golet ◽

Molly E. Lutcavage

Keyword(s):

Gulf Of Maine ◽

Bluefin Tuna ◽

Thunnus Thynnus ◽

Atlantic Bluefin Tuna

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Results of pop-up satellite tagging of spawning size class fish in the Gulf of Maine: do North Atlantic bluefin tuna spawn in the mid-Atlantic?

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-016 ◽

1999 ◽

Vol 56 (2) ◽

pp. 173-177 ◽

Cited By ~ 116

Author(s):

Molly E Lutcavage ◽

Richard W Brill ◽

Gregory B Skomal ◽

Bradford C Chase ◽

Paul W Howey

Keyword(s):

North Atlantic ◽

Gulf Of Maine ◽

Bluefin Tuna ◽

Stock Structure ◽

Migration Patterns ◽

Spawning Period ◽

Atlantic Bluefin Tuna ◽

Spawning Areas ◽

Mixing Rates ◽

Satellite Tagging

Twenty giant bluefin tuna were captured in September and October 1997 and tagged and released with pop-up satellite tags programmed to jettison from March through July, 1998. Seventeen tags successfully released from the fish (12 during the known May-July spawning period), all of which were located north of 33°N latitude, in a region of the mid-Atlantic bounded by Bermuda and the Azores. Our results argue for reconsideration of current assumptions about North Atlantic bluefin tuna migration patterns, mixing rates, spawning areas, and stock structure and highlight the need for additional studies.

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Measurements of juvenile Atlantic bluefin tuna (Thunnus thynnus) size using an unmanned aerial system

Journal of Unmanned Vehicle Systems ◽

10.1139/juvs-2018-0039 ◽

2020 ◽

Vol 8 (2) ◽

pp. 140-160

Author(s):

J. Michael Jech ◽

Jennifer J. Johnson ◽

Molly Lutcavage ◽

Angelia S.M. Vanderlaan ◽

Yuri Rzhanov ◽

...

Keyword(s):

Gulf Of Maine ◽

Digital Camera ◽

Bluefin Tuna ◽

Aerial Images ◽

Fish Length ◽

Motion Sensors ◽

Thunnus Thynnus ◽

Additional Information ◽

Atlantic Bluefin Tuna ◽

Accuracy And Precision

An APH-22 vertical-takeoff-and-landing hexacopter was used to collect aerial images of schools and individuals of juvenile Atlantic bluefin tuna (ABFT; Thunnus thynnus) at the sea surface in the southern Gulf of Maine. Quantitative measures of fish length, width, and inter-fish spacing were obtained from these images by applying calibration settings and performance measures from calibrating, testing, and evaluating the onboard motion and altimeter sensors and the digital camera and lenses. The accuracy and precision of the onboard motion sensors, camera, and lens calibrations were sufficient to provide length measurements to sub-centimeter precision, but the altimeter performance was least reliable and required additional information, such as images of known-sized objects during each flight, to provide measurements at the accuracy and precision needed for data to be incorporated in fisheries management. The APH-22 was ideal for acquiring images of ABFT individuals and schools and may be a useful tool for remotely monitoring the behavior and body condition of these elusive animals.

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