Fluctuating asymmetry in the size of the otolith of Engraulis australis (Shaw, 1790) recovered from the food of the Australasian gannet, Morus serrator, Hauraki Gulf, New Zealand

• Published in: Marine pollution bulletin Vol. 168; p. 112391
• Main Authors: Jawad, Laith A., Adams, Nigel J.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-07-2021; Elsevier BV
• Subjects: Bilateral asymmetry; Colonies; Contaminants; Engraulis australis; Fish; Fluctuating asymmetry; Food; Foods; Length; Morphometry; Otolith length; Otolith width; Pollution; Seabirds; Width; New Zealand; Hauraki Gulf; Otolith length; Pollution; Bilateral asymmetry; Morphometry; Otolith width
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2021.112391

The fluctuating asymmetry values of the two otolith parameters: length and width of Engraulis australis, recovered from the food of gannet, which inhabit colonies in islands at Hauraki Gulf, New Zealand was calculated in this study. The dissimilarity value of the otolith width was higher than that of the otolith length. An inclination of upsurge in the dissimilarity values with the fish length was noted for the otolith sizes studied. The dissimilarity value in the two otolith sizes was the lowest for fish having total length of 115–154 mm, and the highest for fish with length of 151–160 mm. The conceivable reason of the dissimilarity obtained could be related to diverse contaminants and their presence in the study location.
•The fluctuating asymmetry value of the two otolith parameters length and width of Engraulis australis was calculated.•The level of asymmetry of the otolith width was higher than for otolith length.•A tendency of increase in the asymmetry values with the fish length was observed for the otolith length and width.•The lowest level of asymmetry examined is for fish between 115-154 mm in length and the highest between 151-160 mm.•The possible reason of the asymmetry has been discussed in the area in relation to pollution.