Retraction Note: Novel life history strategy in a deep sea fish challenges assumptions about reproduction in extreme environments

Abstract The deep ocean is frequently assumed to be a homogeneous system lacking the same diverse life history strategies found in shallower waters. However, as our methods for exploring the deep ocean improve, common assumptions about dispersal, reproduction and behavior are constantly being challenged. Fishes exhibit the most diverse reproductive strategies among vertebrates. Understanding life history strategies in deep-sea environments is lacking for many species of fishes. Here, we report a novel reproductive strategy where a fish (Parazen pacificus) provides parental care via mouth brooding. This behavior is observed from a specimen collected with eggs present in the buccal cavity, along with other specimens exhibiting pre-brooding morphologies. This is the first description of this unique life history trait in a deep-sea fish and fills in a gap in the larval literature for this family of fishes and prompts further investigation into other novel reproductive modes of deep-sea fauna.

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Contributions to Management Strategies in the NE Atlantic Regarding the Life History and Population Structure of a Key Deep-Sea Fish (Mora moro)

Biology ◽

10.3390/biology10060522 ◽

2021 ◽

Vol 10 (6) ◽

pp. 522

Author(s):

Régis Santos ◽

Wendell Medeiros-Leal ◽

Osman Crespo ◽

Ana Novoa-Pabon ◽

Mário Pinho

Keyword(s):

Population Structure ◽

Life History ◽

Deep Sea ◽

Management Strategies ◽

Size Composition ◽

Large Size ◽

The Common ◽

Fishing Impacts ◽

Sea Fish

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.

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Genome size variation in deep-sea amphipods

Royal Society Open Science ◽

10.1098/rsos.170862 ◽

2017 ◽

Vol 4 (9) ◽

pp. 170862 ◽

Cited By ~ 3

Author(s):

H. Ritchie ◽

A. J. Jamieson ◽

S. B. Piertney

Keyword(s):

Life History ◽

Genome Size ◽

Deep Sea ◽

Research Effort ◽

Life History Strategy ◽

Size Variation ◽

Genome Size Variation ◽

New Hebrides ◽

Contrast Analysis ◽

Independent Contrast

Genome size varies considerably across taxa, and extensive research effort has gone into understanding whether variation can be explained by differences in key ecological and life-history traits among species. The extreme environmental conditions that characterize the deep sea have been hypothesized to promote large genome sizes in eukaryotes. Here we test this supposition by examining genome sizes among 13 species of deep-sea amphipods from the Mariana, Kermadec and New Hebrides trenches. Genome sizes were estimated using flow cytometry and found to vary nine-fold, ranging from 4.06 pg (4.04 Gb) in Paralicella caperesca to 34.79 pg (34.02 Gb) in Alicella gigantea . Phylogenetic independent contrast analysis identified a relationship between genome size and maximum body size, though this was largely driven by those species that display size gigantism. There was a distinct shift in the genome size trait diversification rate in the supergiant amphipod A. gigantea relative to the rest of the group. The variation in genome size observed is striking and argues against genome size being driven by a common evolutionary history, ecological niche and life-history strategy in deep-sea amphipods.

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A contribution to the life history and distribution of Atlantic species of the deep-sea fish genus Conocara (Alepocephalidae)

Deep Sea Research Part A Oceanographic Research Papers ◽

10.1016/0198-0149(86)90019-1 ◽

1986 ◽

Vol 33 (9) ◽

pp. 1183-1201 ◽

Cited By ~ 21

Author(s):

Roy E. Crabtree ◽

Kenneth J. Sulak

Keyword(s):

Life History ◽

Deep Sea ◽

Sea Fish

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Transcriptome of the Deep-Sea Black Scabbardfish,Aphanopus carbo(Perciformes: Trichiuridae): Tissue-Specific Expression Patterns and Candidate Genes Associated to Depth Adaptation

International Journal of Genomics ◽

10.1155/2014/267482 ◽

2014 ◽

Vol 2014 ◽

pp. 1-21 ◽

Cited By ~ 8

Author(s):

Sergio Stefanni ◽

Raul Bettencourt ◽

Miguel Pinheiro ◽

Gianluca De Moro ◽

Lucia Bongiorni ◽

...

Keyword(s):

Deep Sea ◽

High Throughput Sequencing ◽

Expression Patterns ◽

Extreme Environments ◽

Cdna Libraries ◽

Sequencing Analysis ◽

Specific Expression ◽

Adaptation Processes ◽

Sea Fish

Deep-sea fishes provide a unique opportunity to study the physiology and evolutionary adaptation to extreme environments. We carried out a high throughput sequencing analysis on a 454 GS-FLX titanium plate using unnormalized cDNA libraries from six tissues ofA. carbo. Assemblage and annotations were performed by Newbler and InterPro/Pfam analyses, respectively. The assembly of 544,491 high quality reads provided 8,319 contigs, 55.6% of which retrieved blast hits against the NCBI nonredundant database or were annotated with ESTscan. Comparison of functional genes at both the protein sequences and protein stability levels, associated with adaptations to depth, revealed similarities betweenA. carboand other bathypelagic fishes. A selection of putative genes was standardized to evaluate the correlation between number of contigs and their normalized expression, as determined by qPCR amplification. The screening of the libraries contributed to the identification of new EST simple-sequence repeats (SSRs) and to the design of primer pairs suitable for population genetic studies as well as for tagging and mapping of genes. The characterization of the deep-sea fishA. carbofirst transcriptome is expected to provide abundant resources for genetic, evolutionary, and ecological studies of this species and the basis for further investigation of depth-related adaptation processes in fishes.

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Exploitation of deep-sea fishery resources

Natural Capital and Exploitation of the Deep Ocean ◽

10.1093/oso/9780198841654.003.0004 ◽

2020 ◽

pp. 71-90

Author(s):

Les Watling ◽

Lissette Victorero ◽

Jeffrey Drazen ◽

Matthew Gianni

Keyword(s):

Life History ◽

Fisheries Management ◽

Deep Sea ◽

Environmental Harm ◽

Fishing Gear ◽

Bottom Trawling ◽

Fish Stocks ◽

Sea Bottom ◽

Fish Catch ◽

Sea Fish

Deep-sea fisheries occur at depths between 200 and 1800 m, using bottom trawls, long lines, and occasionally pots and gillnets. These fisheries were of minor interest and value until the mid-1980s when large stocks of fish were discovered, mostly on high-seas seamounts. However, because of the life-history characteristics of deep-dwelling fish, most seamount fish stocks were soon overfished, and few have recovered. Total deep-sea fish catch since 1950 represents about 3 per cent of the global catch, yet the environmental harm caused to deep-sea bottom communities by bottom trawling is extensive and long lasting, far exceeding the value of the fishery. In response, the United Nations has passed several resolutions since 2004 requiring the establishment of regional fisheries management organisations (RFMOs) who would be responsible for setting catch limits for the target species and requiring actions that would limit the damage to the habitat by fishing gear. To date, the latter of these two requirements, at least, has not been successfully met.

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