Performance of two larval fish samplers, a hand-towed net and a dropbox enclosure, was similar when tested in shallow (X water depth, 20 cm) upper littoral-zone habitats. There was no significant difference between means of larval fish density (by total catch and by species) estimated from the catch in each gear, during the day and at night. Mean length of larvae (total catch) from the tow net was significantly longer than that from the dropbox during the day, but mean length did not differ between gear at night. Mean lengths of larvae of each species between gear were not significantly different within each period. Both gears collected significantly longer larvae (total catch and by species) during the day than at night probably because of die1 movements of larvae of different sizes and species.
A list is given of shore fishes known from Howland and Baker Islands, outliers of the Phoenix Islands group, and Jarvis Island, Palmyra Atoll, and Kingman Reef in the Line Islands group. The list was compiled from literature sources, museum collection databases, and surveys conducted in 2000-2008 by the NOAA Pacific Islands Fisheries Science Center's Coral Reef Ecosystem Division (CRED). A total of 506 shore-fish species and 27 epipelagic species were recorded from the five islands. Of the shore-fish species, 41 (8.1%) were first noted in our CRED surveys. Numbers for the individual islands are: Howland Island-328 species of which 166 (50.8%) are first records from CRED sampling; Baker Island-268 species with 188 (70.1%) as new CRED records; Jarvis Island-274 species with 176 (64.2%) as new CRED records; Palmyra Atoll-395 species with 113 (28.6%) as new CRED records; and Kingman Reef-270 species with 212 (78.5%) as new CRED records. Fifteen additional species whose identifications are in need of verification were reported in our surveys or previous efforts. An additional 16 are considered suspect identifications of species that probably do not occur at the Line or Phoenix Islands. Differences in the species composition of the five islands are discussed in the context of habitat diversity, historic sampling effort, and regional oceanography. The evolution of shore-fish species found at these central Pacific islands is reviewed in the context of phylogeographic information, geology of Pacific islands, and regional oceanography. It is argued that oceanography and dispersal have played a larger role than geologic adjacencies in the evolution of central Pacific oceanic island fishes. Knowledge of the fish fauna of the central equatorial Pacific remains incomplete, in part, because of limited sampling of small, nocturnal, or otherwise cryptic species. These five islands are
A second species of Grammatonotzts from the Hawaiian Islands, tentatively identified as G. macrophthalmus Katayama, Yamamoto & Yamakawa (Callanthiidae), is recorded from French Frigate Shoals and the Northampton Seamount based on observations from a research submersible. In the absence of collected specimens, identification was made by comparing characters visible in video images with previously published images and descriptions. The fish were observed from 340 to 440 m at or near rocky habitats with crevices. All of the observations were near current-swept areas that supported gold coral (Gerardia sp.) colonies, although the fish were never seen within the colonies. A habitat feature important for both Grammatonotus and Gerardia, such as current or planktonic food supply, may therefore influence distribution of the fish. Extensive fish surveys conducted in comparable depths at other areas of the archipelago have not encountered this species, with one poorly documented exception from trawling surveys. Two other range extensions of Grammatonotzts are included herein: Grammatonotzts laysanus Gilbert from the Line Islands with a specimen collected at Christmas Island at 274 m and an unidentified Grammatonotzts juvenile from the Tuamotu Archipelago at 705 m. Our examination of specimens and review of previous records of Grammatonotus indicate that this genus needs taxonomic revision.THE FISH FAUNA of the Hawaiian Islands is better known than that of any other Pacific island group. Despite this, species previously unrecorded from these Islands continue to be found. Many of these are small and/or deepwater species from poorly sampled habitats. In this paper, we document spectacularly col-
Blackwater diving,'' or nighttime SCUBA diving in epipelagic environments, has become highly popular in recent years because lay participants encounter animals that are difficult and expensive to observe through other methods. These same observations can be priceless for researchers working with these species, so an interface between the scientific communities and recreational divers would be mutually beneficial. In this paper, we describe one such interface through the photography, collection, and DNA barcoding of larval fishes from the island of Hawaii. The images and videos from this activity provide an exciting window into the epipelagic environment and the way larval fishes appear and swim within it. Blackwater diving allows us to see the often-elaborate appendages and other specializations of these larvae as they appear in situ, prior to extensive net and fixation damage. However, blackwater diving remains an almost exclusively recreational pursuit, particularly popular among underwater photographers, who have little interest in (or object to) collecting specimens for scientists. Nonetheless, a logical next step is careful hand collection of specimens for scientific study. Growing numbers of recreational divers around the world have access to an otherwise expensive-to-research habitat. Here we present, for the first time, in situ and post-fixation photos of larval fishes that were hand collected and fixed in 95% ethanol by blackwater divers operating out of Kona, Hawaii, with DNA barcode identifications congruent with morphology and pigmentation where possible. With the right motivation, blackwater diving could augment research in the pelagic ocean and significantly enhance natural history collections and our knowledge of the larvae of marine fishes.
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