Reproductive benefits of no-take reserves vary atitudinally for Plectropomus leopardus
Conference Contribution ResearchOnline@JCUAbstract
No-take marine reserves (NTRs) are expected to benefit fisheries via recruitment subsidy to fished areas. Quantifying the contribution of NTRs to egg production is the first step in evaluating the potential for recruitment subsidy. We quantified annual fecundity and egg production per unit area (EPUA) for the commercially important common coral trout, Plectropomus leopardus, between fished and NTR reefs in four Great Barrier Reef (GBR) regions. Reproductive potential between NTRs and fished reefs varied significantly among latitudes. Fecundity was approximately 200% greater and EPUA 260% greater on NTRs than fished reefs in the central GBR. Annual fecundity and EPUA were significantly greater on fished reefs than NTRs in the northern GBR. It was difficult to detect differences between NTRs and fished reefs in the southern GBR because of small numbers of spawners available to measure fecundity, despite overall greater abundances in the south. Plectropomus leopardus densities were 2-5 times lower in the central GBR than the north or south but higher proportions of reproductively mature females meant EPUA on central GBR NTRs was 1800- 4500% greater than on NTR reefs in the two southern regions and 530% greater than reefs in the northern region. Male biased sex ratios, infrequent spawning, and low annual fecundity in the southern GBR limited the prospective reproductive benefits expected from significantly higher population densities. This study highlights the importance of considering spatial variation in EPUA when assessing prospective benefits of NTRs, particularly if recruitment subsidy is an objective of NTR implementation.
Journal
N/A
Publication Name
12th International Coral Reef Symposium
Volume
N/A
ISBN/ISSN
N/A
Edition
N/A
Issue
N/A
Pages Count
2
Location
Cairns, QLD, Australia
Publisher
International Coral Reef Symposium
Publisher Url
N/A
Publisher Location
Cairns, QLD, Australia
Publish Date
N/A
Url
N/A
Date
N/A
EISSN
N/A
DOI
N/A