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Lutjanid snappers belonging to the subfamilies Apsilinae and Etelinae are commercially valuable components of tropical deep-water fisheries throughout much of the Indo-Pacific region. Based on age assessment using sagittal otoliths, the age-specific demographic characteristics of four deep-water snappers, Etelis coruscans, Paracaesio caerulea, Pristipomoides filamentosus and Pristipomoides sieboldii, in the Okinawa Islands, southwestern Japan, were examined, and the results were discussed for fishery management. Age validation using edge-type analysis demonstrated that opaque zones in all species were formed once per year and were considered valid annual growth increments. The von Bertalanffy growth equations were also determined for each species. These snappers are long-lived (>50 years for E. coruscans and P. caerulea and >30 years for the two species of Pristipomoides) and relatively slow-growing. The age of acquiring sexual maturity in females was relatively later in E. coruscans, P. caerulea and P. filamentosus than in P. sieboldii. The results revealed differences in the biological traits among these four species; E. coruscans and P. caerulea with long life spans and late maturation are particularly more vulnerable to fishing impact than the two Pristipomoides species. Therefore, further approaches to decrease and control fishing intensity, such as networking of marine-protected areas and regulation to control the numbers of boats and/or the total allowable catch, are necessary for the management of the stock of these species, especially for E. coruscans and P. caerulea., (© 2020 The Fisheries Society of the British Isles.)

The most common goatfishes in Hawai'i, Mulloidichthys flavolineatus and M. vanicolensis, comprise a unique resource due to their cultural, ecological and biological significance. These species exhibit pulse-type recruitment to nearshore areas during the summer months. Such pulses of juvenile fishes provide prey for pelagic and nearshore fishes and support a popular directed fishery. However, limited scientific information exists on juvenile stages of these fishes, known locally as oama, despite their contribution to coastal ecology and the extensive nearshore fisheries. Here we resolve growth rates, habitat preferences, hatching dates, size and age structure, as well as fishing catch rates based on new recruits in 2014 and 2015. We sampled 257 M. flavolineatus and 204 M. vanicolensis to compare ecological and fisheries characteristics between species and years. Both show strong habitat segregation, with M. vanicolensis found almost exclusively on hard and M. flavolineatus on soft substrates. Oama recruited in anomalously high numbers in 2014, a trend reflected in a higher catch per unit effort. In contrast, 2015 recruits grew faster, were heavier on average and hatched later than during 2014. Both species have calculated hatch dates in March to July, with M. vanicolensis hatching earlier, recruiting earlier and being consistently larger than M. flavolineatus. This baseline information regarding recruitment and early life-history characteristics can enhance management for other data-limited species that comprise a substantial component of nearshore fisheries in Hawai'i., (© 2019 The Fisheries Society of the British Isles.)