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Comparison of life histories of two deep-water sharks from eastern Australia: the piked spurdog and the Philippine spurdog
journal contribution
posted on 2023-05-19, 02:18 authored by Rigby, CL, Daley, RK, Simpfendorfer, CADeep-water sharks have low biological productivity and are vulnerable to exploitation with species-specific regional life history required to enable effective management. The present study describes the life history of two squalids collected from Australia: (1) the piked spurdog (Squalus megalops) from the tropical Great Barrier Reef; and (2) the Philippine spurdog (S. montalbani) from New South Wales. Maximum observed ages for males and females were 18 and 25 years for S. megalops and 28 and 27 years for S. montalbani. Multiple growth models were all well supported and indicated very slow growth rates for both species. The tropical S. megalops population was smaller and older at maturity than previously reported temperate populations. Males were mature at 352-mm stretched total length (LST) and 12.6 years, whereas females were mature at 422 mm LST and 19.1 years. Squalus montalbani males were mature at 700 mm LST and 21.8 years, whereas females were mature at 800 mm LST and 26 years. Fecundity was lower for S. megalops than S. montalbani with two to three compared with nine to 16 embryos. Both species have a conservative life history, although in the event of overfishing the longer-lived, later-maturing and deeper-dwelling S. montalbani is likely to take longer to recover than S. megalops.
History
Publication title
Marine and Freshwater ResearchVolume
67Issue
10Pagination
1546-1561ISSN
1323-1650Department/School
Institute for Marine and Antarctic StudiesPublisher
CSIRO PublishingPlace of publication
150 Oxford St, Po Box 1139, Collingwood, Australia, Victoria, 3066Rights statement
Journal compilation copyright CSIRO 2016Repository Status
- Restricted