Ocean Sciences [OS]

OS45Q HCC:HALL 3 Thursday

Deep-Sea Fish Diversity and Ecology in the Benthic Boundary Layer III Posters

Presiding:J Drazen, University of Hawaii; J Moore, Fla. Atlantic University


Horizontal and vertical distribution of mesopelagic fishes with special reference to {\it Vinciguerria lucetia} (Phosichthyidae:Pisces) in the Humboldt Current region off Peru

* Cornejo, R (rocornejo@udec.cl) , Departamento de Oceanografia, Universidad de Concepcion, Cabina 9, Concepcion, 160-C Chile
Koppelmann, R (koppelmann@uni-hamburg.de) , Institute of Hydrobiology and Fisheries Sciences, University of Hamburg, Zeiseweg 9, Hamburg, D-22765 Germany
Sutton, T (TSutton@HBOI.edu) , Harbor Branch Oceanographic Institution, 5600 U.S. 1 North, Florida, United States

The horizontal and vertical distribution of adult mesopelagic fishes is described from acoustic-trawls sampling over the full-depth of 500 m at 169 stations on a longitudinal transect between 50 to 200 nautical miles crossing the Humboldt Current off Peru coast ($03\deg$45'S, $81\deg$76'W and $18\deg$23'S, $71\deg$13'W) during austral spring (october-november) of 2001, 2002 and 2003. A total of 2952 kg of fishes were collected and included 28 species belonging to 23 genera. The mesopelagic community is dominated by the fish families Phosichthyidae ({\it Vinciguerria lucetia} ), Myctophidae ({\it Diogenichthys laternatus} and {\it Lampanyctus idostigma}) and Bathylagidae ({\it Leuroglossus urotranus}), corresponding respectively 84.48 %, 7.19 %, 2.18 % and 1.06 % of the total abundance. Based on horizontal distribution patterns these species were categorized into three groups, i.e. Humboldt north-central group ({\it Leuroglossus urotranus, Nemichthys fronto and Scopelarchoides nicholsi }), Humboldt south group ({\it Hygophum reinhardti, Myctophum nitidulum, Paralepis sp and Scopeloberyx sp.})and Pan-Humboldt group ({\it Vinciguerria lucetia, Diogenichthys laternatus, Lampanyctus(Nannobrachium) idostigma, L. omostigma, M. aurolaternatum, Triphoturus oculeus, Melanolagus berycoides, Leuroglossus stilbius, Argyropelecus affinis, Sternoptyx obscura, Melamphaes sp., Stomias sp., Scopelosaurus sp}). Night-time vertical distribution was characterized by single abundance peak in the upper 50 m. Day-time patterns showed 3 peaks of abundance, an upper abundance peak, occurring in the upper 100 m, a midwater abundance peak, over a wider depth range (200-400 m), coinciding with oxygen mimimum zone and a near-bottom abundance peak, occurring between 400-500 m. ({\it Vinciguerria lucetia }) was dominant in upper and midwater peaks while myctophids, other planctivores and piscivorous fishes were distributed in the midwater and deeper peaks. Backscattered energy (Sa) were ubiquitous in the region. Maximum Sa was mainly located between 11 and 18S during day-night time. ({\it Vinciguerria lucetia }) is significant in the oceanic pelagic ecosystem as a major component of fish biomass in deep scattering layer in the Humboldt Current region off Peru and probably of transitional waters in the southeastern Pacific. Keywords: Mesopelagic fishes, ({\it Vinciguerria lucetia}) , Humboldt current, Peru, vertical and horizontal distribution, Backscattering energy


Systematics of Stomiiform Fishes: Phylogeny and Evolution in the Deep Ocean

* DeVaney, S C (scd@ku.edu) , University of Kansas, Natural History Museum and Biodiversity Research Center, 1345 Jayhawk Blvd., Lawrence, KS 66045 United States

In phylogenetic systematics, as in other areas of biology, deep ocean organisms remain enigmatic, poorly understood, and difficult to study. The order Stomiiformes (Teleostei) is a widespread and abundant group of meso- and bathypelagic fishes whose interrelationships are still problematic, despite significant progress made by previous investigators using morphological data. The present study is a new analysis of stomiiform relationships based mostly on DNA sequence data from the single-copy nuclear genes RAG1, EF1a, and MLL, addressing the placement of Stomiiformes within the fish tree of life and the monophyly and relationships of major clades within the order. Particular attention is given to regions of the tree in which the molecular data conflicts with previous hypotheses based on morphology. The implications of stomiiform phylogeny for broader questions in deep-sea biology, including character evolution, ecology, biogeography, and speciation, are also discussed.


Preliminary Measurements of Metabolic Rates and Decompression Tolerance in Deep-Sea Benthopelagic Fishes

* Drazen, J C (jdrazen@hawaii.edu) , University of Hawaii, MSB205 1000 Pope Rd, Honolulu, HI 96822 United States
Barry, J P (barry@mbari.org) , Monterey Bay Aquarium Research Institute, 7700 Sandholdt Rd, Moss Landing, CA 95039 United States
Bird, L E (bila@mbari.org) , Monterey Bay Aquarium Research Institute, 7700 Sandholdt Rd, Moss Landing, CA 95039 United States

Deep-sea benthopelagic fishes are often among the top predators in their habitats. Despite their ecological importance few measurements of energetic parameters have been made. Many of these animals have gasbladders which makes their retrieval to the surface for laboratory investigations difficult or impossible. In order to perform physiological experiments on deep-sea fishes under in situ but controlled conditions we constructed a high-pressure fish trap-respirometer to capture these animals at depth and return them to the surface alive at in situ pressure and temperature. Pumps and instrumentation connected aboard ship or in the laboratory are used for maintenance of the animal and experimentation. The trap was designed so that respiration rates, pressure tolerance, and metabolic responses to various gas concentrations (CO$_{2}$ and O$_{2}$) could be examined in a controlled environment. The trap is deployed as an autonomous lander or free vehicle to depths of 4000 m. Once on the seafloor a fish is captured on a baited hook which triggers the reeling of the fish into the pressure vessel and closure of its sealing door. Several fishes, including the rattail {\it Coryphaenoides acrolepis}, have been captured at depth in Monterey Bay, California and retrieved to the surface at or near in situ conditions and maintained in the laboratory. We will present preliminary measurements of their metabolic rates and decompression tolerances.


Age, Growth and Reproduction of the Barrelfish, Hyperoglyphe perciformis (Mitchill, 1818)

* Filer, K R (krf3c@yahoo.com) , College of Charleston, 205 Fort Johnson Rd., Charleston, SC 29412 United States
Sedberry, G (sedberryg@dnr.sc.gov) , Marine Resources Research Institute, South Carolina Department of Natural Resources, 217 Fort Johnson Rd., Charleston, SC 29412 United States

Commercial and recreational fishermen in the southeastern United States have traditionally focused their efforts on species of fish on the continental shelf; but, as these stocks continue to decline, more commercial fishermen have begun to fish in the deeper slope waters. Fishes that occur there are slower-growing, often larger species that tend to mature later than many of their shallow water counterparts, making them vulnerable to rapid declines in population size with increasing fishing pressure. In order to appropriately manage these deepwater species, more information is needed, such as where and when they reproduce, and size and age at first reproduction. One deepwater (>400 m) species off South Carolina for which there is very little biological information is the barrelfish, Hyperoglyphe perciformis (Mitchill, 1818). The goal of this project is to enhance the biological knowledge of this species by determining age, growth and reproduction of the barrelfish. Specimens of barrelfish were collected from 2001 through November of 2005 from fishermen who catch them around the Charleston Bump, a topographic feature located in the Gulf Stream at depths of 400 m to 800 m between latitudes 31$\deg$N and 32$\deg$N. For each fish, lengths, weight, otoliths and gonads were obtained. To date, approximately 800 otoliths have been sectioned and read. The mean number of increments per otolith thus far is 16.6, with a minimum number of 5, and a maximum of 80. It is believed that one opaque increment is formed per year, but marginal increment analysis will help elucidate this. Additionally, 11 otolith cores are being processed for radiocarbon dating, with results pending. Approximately 750 gonads have been prepared and examined for sex and reproductive stage. The barrelfish is a gonochoristic species which spawns during the winter months around the Charleston Bump, as is evidenced by the presence of post-ovulatory follicles. Size and age at first maturity, at 50% maturity, and at 100% maturity will be estimated, and sex ratios will be determined for each size and age class upon completion of sampling in November of 2005.


Autonomous Shark Tag with Neural Reading and Stimulation Capability for Open-ocean Experiments

* Gomes, W J (gomeswj@npt.nuwc.navy.mil) , Naval Undersea Warfare Center, 1176 Howell Street, Newport, RI 02841 United States

NUWC is developing a fish tag whose goal is attaining behavior control of host animals via neural implants. This talk discusses a shark tag with multi-channel neural ensemble readers and stimulators, diverse controllers and sensors. Recent results and ongoing work will be discussed. The tag is intended for long-term open ocean field efforts investigating viability of animal behavior control and its utility for networked sensing and data acquisition. The tag is centered on a multi-channel neural ensemble reader, a processor to interpret the readings in real-time, and a multi-channel stimulator, intended for both micro and macro stimulation. Additional capabilities include an undersea navigation/tracking system, acoustic and RF communication capabilities, a sensitive multi-channel Electric field measurement sensor, and a range of environmental sensors, including ph, heading and motion sensors, temperature, pressure and chemical injection micro-pumps. The design is field-reconfigurable, modular, and allows multiple sensor and controller variants to be easily configured. Ongoing work on energy harvesting methods to power the tag will be discussed. The key mechanical issue is facilitating electrode implantation and tag attachment. This talk will address methods of tag attachment, streamlining issues, acoustic transducer and RF antenna placement and performance. Electrode implantation procedures are addressed by our research collaborators. To date results include neural ensemble recordings and stimulation of Mustelus Canis and Squyalus Acanthias. Current work is focusing on E-field measurements with Sphyrna Lewini and open-ocean work with Prionace Glauca.


Emerging Patterns of Small-scale and Large-scale Distributions of Fishes Associated With Western North Atlantic Seamounts

* Moore, J A (jmoore@fau.edu) , Florida Atlantic University, Wilkes Honors College 5353 Parkside Dr, Jupiter, FL 33458 United States
Auster, P J (auster@uconn.edu) , National Undersea Research Center, University of Connecticut at Avery Point, Groton, CT 06340 United States
Heinonen, K , National Undersea Research Center, University of Connecticut at Avery Point, Groton, CT 06340 United States

Data from six years of trawling and three years of submersible investigations of western North Atlantic seamounts are compiled to begin understanding the distribution of fishes associated with these seamounts. Submersible video transects provide the data for smaller-scale distributions. The small-scale distribution of benthic and benthopelagic fishes is non-random and may be related to landscape features of bottom type, structure, depth and flow regime. Large-scale patterns of distribution are based on both trawl surveys and submersible video transects. These provide preliminary information as to which seamounts the various fish species are found and potential dispersal patterns.


The Fish Community of a Canyon Ecosystem on the Middle Continental Slope Off Cape Hatteras, NC: Comparisons North and South

* Necaise, A (amnecaise@att.net) , Univ. of North Carolina at Wilmington, Center for Marine Science 5600 Marvin Moss Ln, Wilmington, NC 28409 United States
Ross, S W (rosss@uncw.edu) , Univ. of North Carolina at Wilmington, Center for Marine Science 5600 Marvin Moss Ln, Wilmington, NC 28409 United States
Ross, S W (rosss@uncw.edu) , US Geological Survey, Florida Integrated Science Center, 7920 NW 71 St, Gainesville, Fl 32653 United States
Quattrini, A M (quattrinia@uncw.edu) , Univ. of North Carolina at Wilmington, Center for Marine Science 5600 Marvin Moss Ln, Wilmington, NC 28409 United States
Sulak, K J (ken_sulak@usgs.gov) , US Geological Survey, Florida Integrated Science Center, 7920 NW 71 St, Gainesville, Fl 32653 United States

During the last decade the continental slope just north of Cape Hatteras has been the subject of numerous studies. This area is physically and biologically unique, representing a biological and oceanographic transition area. Several major current systems (e.g., Gulf Stream, Western Boundary Undercurrent) interact in this area, a persistent nepheloid layer exists near the bottom, and the bottom topography is a very rugged, soft sediment canyon system. During 1991, 1992, 1999, 2000, and 2001 we conducted fish studies through the entire column in this area (locally called "The Point"). Benthic data were collected using a submersible conducting visual/video transects, supplemented with still photography and specimen collection. Additional benthic data were collected using otter trawls. Data were collected on fish species composition, habitat relationships, size structure, and feeding habits over a depth range of 150-950 m. The fish fauna in this area was very different from those about 150 km to the north and south of this area. Of a total of 109 benthic/benthopelagic fish species identified, the fauna was numerically dominated by relatively few species: {\it Lycenchelys verrillii}, {\it Glyptocephalus cynoglossus}, {\it Nezumia bairdii}, {\it Urophycis regia}, {\it Setarches guenteri}, and {\it Myxine glutinosa}. Most fishes tended to be at the smaller end of their known size ranges, and larger, more active fishes were missing or uncommon. The dominant fishes consumed a diverse array of benthic food items, exhibited high percentages of gut fullness and displayed differences among species in feeding patterns. Stable isotope data and observations of midwater fauna interacting with the bottom indicated trophic connections with upper layers of the water column. Companion papers (Ross et al. and Gartner et al.) will discuss data related to these observations.


Community Structure of Demersal Ichthyofauna Captured on Longlines in two Areas Along the Northern Mid-Atlantic Ridge

* Cotton, C F (chip@vims.edu) , Virginia Institute of Marine Science, Department of Fisheries Science P.O. Box 1346, Gloucester Point, VA 23062 United States
Fossen, I (Inge@mfaa.no) , Aalesund University College, N-6025, Aalesund, Norway
Dyb, J (janerik@mfaa.no) , Moere Research, Section of Fisheries, P.O. Box 5075, LarsgAard, N-6021, Aalesund, Norway
Bergstad, O (oddaksel@IMR.no) , Institute of Marine Research, Flodevigen Marine Research Station 4817, His, Norway
Musick, J A (jmusick@vims.edu) , Virginia Institute of Marine Science, Department of Fisheries Science P.O. Box 1346, Gloucester Point, VA 23062 United States

As part of the 2004 MAR-ECO survey the longliner M/S Loran caught a total of 8546 fishes, belonging to 43 species and 17 families. Sampling was conducted with 58 longline sets (36 bottom longlines and 22 vertical longlines) within two areas along the Mid-Atlantic Ridge, near the Azores Islands and Charlie Gibbs Fracture Zone (CGFZ). The longlines were set in depths ranging from 400 to 4300 m, with the shallowest areas sampled by vertical longlines. Overall chondrichthyans accounted for 11,935kg of the 20,660kg fish caught (57.8%). This was mainly due to the dominance of {\it Etmopterus princeps} in several stations within both regions. Multidimensional scaling of the catch data indicated the presence of several distinct fish assemblages along the ridge. These were related to both depth and spatial gradients. Large fishes dominated the catch with a mean weight of 2.42 kg. Catch rates peaked at the shallower stations in the CGFZ region, and generally decreased with depth. Average fish weight was lower in the CGFZ region than in the south. No abrupt changes in species composition were found among adjacent stations, but rather changes occurred along a continuum. However, the data suggests that changes in species composition among adjacent stations are more pronounced at certain depths.



Feeding Ecology of Coryphaenoides Rupestris on the mid- Atlantic Ridge

* Gjelsvik, G (Guro.Gjelsvik@student.uib.no)

Trophic studies are necessary to improve our understanding of the marine food webs and community structures. The Macrourid fish roundnose grenadier, Coryphaenoides rupestris, is one of the most common benthopelagic fishes on the northern mid- Atlantic Ridge. This study identifies the significant prey animals of this species, studies their relative significance, and compare the grenadier's feeding strategies on the mid- Atlantic Ridge with those in other areas in the North Atlantic, e.g. the Skagerrak and the Rockall Trough. In total, 166 specimens from the RV G.O. Sars cruise in July 2004 have been examined. Earlier studies have suggested that roundnose grenadier is a benthopelagic predator, mainly feeding on crustaceans, and the study will reveal if this is also the case in the mid-Atlantic. The study is an element of more wide-ranging food-web studies of the mid- Atlantic Ridge macro-and megafauna communities within the international MAR-ECO project.