Bone Density Variation in Rattails (Macrouridae,Gadiformes): Buoyancy, Depth, Body Size, and Feeding

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Extreme abiotic factors in deep-sea environments, such as near-freezing temperatures, low light, and high hydrostatic pressure, drive the evolution of adaptations that allow organisms to survive under these conditions. Pelagic and benthopelagic fishes that have invaded the deep sea face physiological challenges from increased compression of gasses at depth, which limits the use of gas cavities as a buoyancy aid. One adaptation observed in deep-sea fishes to increase buoyancy is a decrease of high-density tissues. In this study, we analyze mineralization of high-density skeletal tissue in rattails (family Macrouridae), a group of widespread benthopelagic fishes that occur from surface waters to greater than 7000 m depth. We test the hypothesis that rattail species decrease bone density with increasing habitat depth as an adaptation to maintaining buoyancy while living under high hydrostatic pressures. We performed micro-computed tomography (micro-CT) scans on 15 species and 20 specimens of rattails and included two standards of known hydroxyapatite concentration (phantoms) to approximate voxel brightness to bone density. Bone density was compared across four bones (eleventh vertebra, lower jaw, pelvic girdle, and first dorsal-fin pterygiophore). On average, the lower jaw was significantly denser than the other bones. We found no correlation between bone density and depth or between bone density and phylogenetic relationships. Instead, we observed that bone density increases with increasing specimen length within and between species. This study adds to the growing body of work that suggests bone density can increase with growth in fishes, and that bone density does not vary in a straightforward way with depth

DEPTH AND DEVELOPMENT OF THE SONIC SYSTEM IN DEEP-SEA MACROURID FISHES ON THE CONTINENTAL SLOPE

Work on sound production of deep-sea fishes has been limited to anatomy, and no sounds from identified species have been recorded on the continental slope. Here I examined the sonic muscles of six species in the family Macrouridae by depth (Coelorhincus carminatus, Nezumia bairdii, Coryphaenoides rupestris, Nezumia equalis, Coryphaenoides armatus, Coryphaenoides carapinus,). Due to increasingly limited food with depth, I hypothesized that sonic muscle development would decrease with depth. Sonic muscles were intrinsic and occurred in males and females. Swimbladder and sonic muscle dimensions increased linearly with fish size, but there were no clear differences with depth suggesting sound production remains important in deeper species

138-Feeding Morphology of Deep-Sea Fishes

Deep-sea fishes have a variety of skull forms, or morphologies, that correspond to their feedingtype. Suction feeders expand their mouths to suck in prey, while biters have large teeth to capture and tear into prey. Many fishes have a second set of jaws, the pharyngeal jaw, in the back of the throat to help ingest and process their catch. We are investigating suction-feeding and biting morphologies to determine if the depth of the fishes\u27 habitat influences the feeding diversity of deep-sea fishes. To find our results, we measured eight fish skulls from the Synaphobranchidae, Macrouridae, Ipnopidae, Ophidiidae, and Liparidae families to analyze the structures that pertain to feeding. Measurements were done using micro-computed tomography (micro-CT) scans of fish heads and the software 3D Slicer.The fishdetermined to be suction feeders were found in depths ranging from 200 meters to 8,300 meters. Fish determined to be biters were found in depths ranging from 90 meters to 7,500 meters.Due to the lever mechanics of a suction-feeder\u27s jaw, these fishescancatch their prey faster than biters. While many fishes appear similar from the outside, they have many feeding adaptations that help them survive in the deep sea

Uso de distribuição binomial negativa para descrever a presença de Sphyrion laevigatum em Genypterus blacodes

This paper describes the frequency and number of Sphyrion laevigatum in the skin of Genypterus blacodes, an important economic resource in Chile. The analysis of a spatial distribution model indicated that the parasites tended to cluster. Variations in the number of parasites per host could be described by a negative binomial distribution. The maximum number of parasites observed per host was two.Este artigo descreve a frequência e o número de Sphyrion laevigatum da pele de Genypterus blacodes, o qual é um importante recurso econômico no Chile. A análise baseada em modelos de distribuição espacial, demonstrou que os parasitos tendem a ficar agrupados. A variação numérica de parasitas por hospedeiro pode ser descrita por distribuição binomial negativa. O número máximo observado de parasitas por hospedeiro foi dois

Depth as a driver of evolution in the deep sea: Insights from grenadiers (Gadiformes: Macrouridae) of the genus Coryphaenoides

Here we consider the role of depth as a driver of evolution in a genus of deep-sea fishes. We provide a phylogeny for the genus Coryphaenoides (Gadiformes: Macrouridae) that represents the breadth of habitat use and distributions for these species. In our consensus phylogeny species found at abyssal depths (> 4000 m) form a well-supported lineage, which interestingly also includes two non-abyssal species, C. striaturus and C. murrayi, diverging from the basal node of that lineage. Biogeographic analyses suggest the genus may have originated in the Southern and Pacific Oceans where contemporary species diversity is highest. The abyssal lineage seems to have arisen secondarily and likely originated in the Southern/Pacific Oceans but diversification of this lineage occurred in the Northern Atlantic Ocean. All abyssal species are found in the North Atlantic with the exception of C. yaquinae in the North Pacific and C. filicauda in the Southern Oceans. Abyssal species tend to have broad depth ranges and wide distributions, indicating that the stability of the deep oceans and the ability to live across wide depths may promote population connectivity and facilitate large ranges. We also confirm that morphologically defined subgenera do not agree with our phylogeny and that the Giant grenadier (formally Albatrossia pectoralis) belongs to Coryphaenoides, indicating that a taxonomic revision of the genus is needed. We discuss the implications of our findings for understanding the radiation and diversification of this genus, and the likely role of adaptation to the abyss

Fishes of the hadal zone including new species, in situ observations and depth records of Liparidae

AbstractObservations and records for fish exceeding 6000m deep are few and often spurious. Recent developments in accessing and sampling the hadal zone 6000–11,000m) have led to an acceleration in new findings in the deep subduction trenches, particularly in the Pacific Ocean. This study describes the discovery of two new species of snailfish (Liparidae) from the Mariana Trench; the ‘Mariana snailfish’ (6198–8076m) and the ‘Ethereal snailfish’ (7939–8145m). These new findings represent respectively the deepest known specimen caught with corroborating depth data, and the deepest fish seen alive. Further specimens and observations of the Kermadec Trench snailfish, Notoliparis kermadecensis, are also presented, as well as the first hadal records of Synaphobranchidae and Zoarcidae (6068 and 6145m respectively) and a depth extension for the Macrouridae (maximum depth now 7012m). Details of these new snailfish specimens caught by baited trap and behaviour observations filmed by baited cameras are presented. An updated assessment of fishes from hadal depths is also reported

Davidson Seamount Taxonomic Guide

Davidson Seamount is one of the largest seamounts in U.S. waters and the first to be characterized as a “seamount.” In 2002 and 2006, the Monterey Bay National Marine Sanctuary (MBNMS) led two multi-institutional expeditions to characterize the geology and natural history of Davidson Seamount. Results from these expeditions to Davidson Seamount are adding to the scientific knowledge of seamounts, including the discovery of new species. In November 2008, the MBNMS boundary was expanded to include the Davidson Seamount. In addition, a management plan for Davidson Seamount was created to develop resource protection, education, and research strategies for the area. The purpose of this taxonomic guide is to create an inventory of benthic and mid-water organisms observed at the Davidson Seamount to provide a baseline taxonomic characterization. At least 237 taxa were observed and are presented in this guide; including 15 new or undescribed species (8 sponges, 3 corals, 1 ctenophore, 1 nudibranch, 1 polychaete, 1 tunicate) recently or currently being described by taxonomic experts. This is the first taxonomic guide to Davidson Seamount, and is intended to be revised in the future as we learn more about the seamount and the organisms that live there. (PDF has 145 pages.

KOMPOSISI JENIS, DISTRIBUSI, DAN KEPADATAN STOK IKAN EKOR TIKUS (MACROURIDAE) DI PERAIRAN LAUT DALAM ZONA EKONOMI EKSKLUSIF INDONESIA SAMUDERA HINDIA

Penelitian ini bertujuan untuk mengkaji, komposisi jenis, penyebaran, dan kepadatan stok ikan ekor tikus (Macrouridae) di perairan laut dalam zona ekonomi eksklusif Indonesia Samudera Hindia meliputi selatan Jawa dan barat Sumatera. Data yang dianalisis merupakan sebagian hasil survei yang dilakukan bulan Juni sampai dengan Agustus 2005 dengan menggunakan K. R. Baruna Jaya (1.219 GT). Estimasi kepadatan stok dilakukan dengan menggunakan metode sapuan dengan pengambilan contoh acak bertingkat. Hasil penelitian menunjukkan bahwa, ikan ekor tikus (Macrouridae) yang tertangkap terdiri atas 35 spesies, mewakili 11 genera. Komposisi hasil tangkapan didominansi oleh spesies Caelorinchus divergens dan Caelorinchus smithi, (19,2 sampai dengan 77,2%). Penyebaran laju tangkap secara horisontal, paling tinggi ditemukan di perairan selatan Jawa, sebaliknya semakin ke arah perairan barat Sumatera, cenderung rendah. Sedangkan secara vertikal, laju tangkap cenderung meningkat seiring dengan bertambah kedalaman. Laju tangkap paling tinggi pada umumnya berada pada kedalaman mulai dari 500 sampai dengan 1.200 m. Jumlah spesies yang tertangkap pada kedalaman lebih dangkal (200 sampai dengan 300 m) relatif sedikit, selanjutnya semakin bertambah kedalaman, jumlah spesies tersebut cenderung meningkat. Spesies yang memperlihatkan penyebaran paling luas terdiri atas Coryphaenoides sp.1 dan Macrouridae sp.1. Kelimpahan stok ikan ekor tikus (Macrouridae) tertinggi ditemukan pada kisaran kedalaman 800 sampai dengan 900 m dan terendah pada kedalaman 200 sampai dengan 300 m. Kepadatan stok di perairan sebelah selatan Jawa, berkisar antara 4 sampai dengan 1.221 kg km-2, rata-rata sekitar 336,53 kg km-2. Sedangkan di perairan barat Sumatera berkisar antara 0,85 sampai dengan 478,4 kg km-2, rata-rata sekitar 167,30 kg km-2. The objective of this research is to study species composition, distribution, and stock density of rattail fish (Macrouridae) in the waters of southern Java and western Sumatera of the Indian Ocean Indonesian ekslusive economic zone. The study was done based on the data collected from the survey conducted between June and August 2005 using R. V. Baruna Jaya IV (1,219 GT). The study was basically conducted by applying swept area method with stratified random sampling. The results show that the species composition of rattail fish in the of the waters Indian Ocean consisted of 35 spesies and 11 genera. The catch of Macrouridae was dominated by Caelorinchus divergens and Caelorinchus smithi about 19.2 to 77.2%. The widest species distribution of this resources was Coryphaenoides sp.1 and Macrouridae sp.1. The highest abundance of rattail fish resources was caught at the depth of 800 to 900 m and the lowest at the depth of 200 to 300 m. Stock density in southern off Java waters ranging from 4 to 1.221 kg km-2 and about 0,85 to 478,4 kg km-2 in western off Sumatera waters

Monitoring the recovery of exploited deep-water species

Commercial fisheries for deep-water species off the Irish coast developed in the late 1990s and declined in the early 2000s. Many of the exploited stocks were depleted a result of commercial exploitation and ICES has advised a zero catch for Orange Roughy since 2004, and for Portuguese Dogfish and Leafscale Gulper shark since 2005. Since 2016, the deep water access regulation has effectively banned trawling in waters deeper than 800 m (EC, 2016) and fishing for deep-water sharks with static netting >600 m is also banned by the technical measures regulation (EC, 2019). However, some of these species continue to be caught, either by gears not covered by this regulation or in water <800 m deep. The Marine Institute carried out a survey programme to assess the distribution and abundance of these species between 1992 and 1999 and again between 2006 and 2009. Since 2019, 3 days of the Irish Anglerfish and Megrim Survey have been allocated to monitoring the recovery of commercial deep-water species. This work was funded under the European Maritime and Fisheries Fund (EMFF) from 2019 to 2021 and European Maritime, Fisheries and Aquaculture Fund (EMFAF) since 2022. The main objective of the current project is to assess the recovery of exploited deep-water species in Irish waters by comparing the results from 2019 to 2022 surveys with those from the previous period in 2006 to 2009 (methods used in the earlier period 1992 to 1999 were different, therefore a direct comparison with that period is not possible).EMFF, EMFAF, the project is co-funded by the Government of Ireland and the European Unio

Sub-Antarctic and High Antarctic Notothenioid Fishes: Ecology and Adaptational Biology Revealed by the ICEFISH 2004 Cruise of RVIB Nathaniel B. Palmer

The goal of the ICEFISH 2004 cruise, which was conducted on board RVIB Nathaniel B. Palmer and traversed the transitional zones linking the South Atlantic to the Southern Ocean, was to compare the evolution, ecology, adaptational biology, community structure, and population dynamics of Antarctic notothenioid fishes relative to the cool/temperate notothenioids of the sub-Antarctic. To place this work in a comprehensive ecological context, cruise participants surveyed the benthos and geology of the biogeographic provinces and island shelves on either side of the Antarctic Polar Front (or Antarctic Convergence). Genome-enabled comparison of the responses of cold-living and temperate notothenioids to heat stress confirmed the sensitivity of the former to a warming Southern Ocean. Successful implementation of the international and interdisciplinary ICEFISH research cruise provides a model for future exploration of the sub-Antarctic sectors of the Indian and Pacific Oceans