Trophic ecology of Squatina guggenheim on the continental shelf off Uruguay and northern Argentina

• Published in: Journal of fish biology 2003-06, Vol.62 (6), p.1254-1267
• Main Authors: Vögler, R., Milessi, A. C., Quiñones, R. A.
• Format: Article
• Language: English
• Subjects: Agnatha. Pisces; Angel shark; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Argentine-Uruguayan Common Fishing Zone; Autoecology; Biological and medical sciences; diet; Engraulis anchoita; Fundamental and applied biological sciences. Psychology; Ilex argentinus; Marine; Squatina guggenheim; top predator; Vertebrata
• ISSN: 0022-1112; 1095-8649
• DOI: 10.1046/j.1095-8649.2003.00105.x

A total of 1280 (670 females and 610 males) Squatina guggenheim, an angel shark endemic to the south‐west Atlantic, was caught during five research cruises (1995, 1997 and 1998) carried out in the Argentine‐Uruguayan Common Fishing Zone (AUCFZ) at depths of 3·5–266 m. All angel sharks captured were sexed and measured. Of the 947 examined for stomach contents, 556 (58·7%) contained food and 391 (41·3%) were empty. Numerically, bony fishes were the principal dietary component (89·7%), followed by crustaceans (4·8%) and molluscs (4·4%). The most important prey species were Engraulis anchoita (58·3%), shrimps (4·4%) and Ilex argentinus (2·3%). Male and female diets were not found to differ significantly (P > 0·01), however, the diets of different size classes showed significant differences (P ≤ 0·01) (group 1, 23–44, group 2, 45–74 and group 3, 75–91 cm LT). Low rates of cannibalism were observed. The spatial and seasonal variability in the trophodynamics of S. guggenheim is discussed.