The swimming kinematics of larval Atlantic cod, Gadus morhua L., are resilient to elevated seawater pC[O.sub.2]

• Published in: Marine biology 2013-08, Vol.160 (8), p.1963
• Main Authors: Maneja, R.H, Frommel, A.Y, Browman, H.I, Clemmesen, C, Geffen, A.J, Folkvord, A, Piatkowski, U, Durif, C.M.F, Bjelland, R, Skiftesvik, A.B
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Environmental aspects; Larval development; Swimming
• ISSN: 0025-3162
• DOI: 10.1007/s00227-012-2054-y

Kinematics of swimming behavior of larval Atlantic cod, aged 12 and 27 days post-hatch (dph) and cultured under three pC[O.sub.2] conditions (control-370, medium-1800, and high-4200 µatm) from March to May 2010, were extracted from swim path recordings obtained using silhouette video photography. The swim paths were analyzed for swim duration, distance and speed, stop duration, and horizontal and vertical turn angles to determine whether elevated seawater pC[O.sub.2]--at beyond near-future ocean acidification levels--affects the swimming kinematics of Atlantic cod larvae. There were no significant differences in most of the variables tested: the swimming kinematics of Atlantic cod larvae at 12 and 27 dph were highly resilient to extremely elevated pC[O.sub.2] levels. Nonetheless, cod larvae cultured at the highest pC[O.sub.2] concentration displayed vertical turn angles that were more restricted (median turn angle, 15°) than larvae in the control (19°) and medium (19°) treatments at 12 dph (but not at 27 dph). Significant reduction in the stop duration of cod larvae from the high treatment (median stop duration, 0.28 s) was also observed compared to the larvae from the control group (0.32 s) at 27 dph (but not at 12 dph). The functional and ecological significance of these subtle differences are unclear and, therefore, require further investigation in order to determine whether they are ecologically relevant or spurious.