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Empirical data quantifying the long-term movement patterns of coral reef top predators are needed in order to design marine
protected areas (MPAs) that will provide these fishes with effective, long-term protection. Acoustic telemetry was used to
quantify the movements of a large coral reef top predator (Aprion virescens, Lutjanidae; Hawaiian name ‘uku’) at five atolls in the Northwestern Hawaiian Islands Marine National Monument (NWHIMNM)
from May 2005 to September 2006. The study atolls were located between 23.8°N, 166.2°W and 28.5°N, 178.3°W, and were separated
from their nearest receiver-equipped neighbor by distances ranging from 100 to 478 km. No inter-atoll movements by uku were
detected but individuals were seasonally site-attached to core activity areas of up to 12 km in length, and ranged up to 19 km
across atolls. Within their core areas, tagged uku exhibited diel and tidal habitat shifts, with the latter resulting in round
trips of up to 24 km in 24 h. Seasonal uku migrations resulted in extended winter (October–April) absences from summer (May–September)
core activity areas and may be linked to summer spawning. Large MPAs (i.e., entire islands, atolls or banks) would probably
be required for full protection of resident populations of adult uku, but such ‘island-scale’ MPAs will not benefit fisheries
unless there is significant larval supply from MPAs to neighboring fished areas, or adult emigration over time scales exceeding
the 16-month monitoring period of this study. A mixed management strategy of combining smaller MPAs with conventional measures
(e.g., minimum size limits, catch, and effort restrictions) may be the best approach for sustaining uku fisheries. However,
this would still require relatively large MPAs (12 km in length) to contain uku short-term (diel and tidal) movements, and
seasonal migrations would still take uku beyond the boundaries of MPAs of this size. These fluxes across MPA boundaries could
supply fish to fisheries but, if high exploitation rates exist, fishing could eliminate key MPA benefits such as increased
numbers of large, highly fecund individuals.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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