First findings of decapod crustacea in the hadal zone

Abstract Since the first major hadal sampling efforts in the 1950s, crustaceans of the order Decapoda have been thought absent from the hadal zone (6000–11,000 m) with no representatives documented >5700 m. A baited video lander deployed at 6007, 6890 and 7966 m in the Kermadec Trench, 8798 and 9729 m in the Tonga Trench (SW Pacific), 6945 and 7703 m in the Japan Trench and 5469 m in the Marianas region (NW Pacific) has now revealed a conspicuous presence of the Benthesicymid prawn Benthesicymus crenatus Bate 1881. Decapods were observed at all sites except at 7966 m in the Kermadec Trench and the two Tonga Trench sites, making the deepest finding 7703 m in the Japan Trench, 2000 m deeper than previously thought. These natantian decapods were readily attracted to fish bait and, rather than feeding on the bait itself, were observed preying upon smaller scavenging amphipods. These are the first observations of predation in the hadal zone. In less than 10 h of bottom time, 12 observations of 10 individuals were documented at 6007 m and 5 observations of 3 individuals were documented at 6890 m in the Kermadec Trench. In the Japan Trench at 6945 m 29 observations of 20 individuals were documented whilst only one individual was seen at 7703 m. Two individuals were observed in the abyssal Marianas Region (5575 m). Also, in the Kermadec Trench, individual caridean prawns ( Acanthephyra spp.) were observed at 6007 and 6890 m, proving categorically that the crustacean order of Decapoda is represented in the hadal zone.

[1]  B. Hargrave,et al.  Estimation of scavenger abundance and distance of attraction to bait , 1987 .

[2]  R. Hessler,et al.  Distribution and behavior of scavenging amphipods from the central North Pacific , 1983 .

[3]  J. Pérês.  Aperçu sur les résultats de deux plongées effectuées dans le ravin de Puerto-Rico par le bathyscaphe Archimède , 1965 .

[4]  P. Domanski.  The near-bottom shrimp faunas (Decapoda: Natantia) at two abyssal sites in the Northeast Atlantic Ocean , 1986 .

[5]  T. Kikuchi,et al.  Deep-sea shrimps of the genus Benthesicymus (Decapoda:Dendrobranchiata) from the western North Pacific. , 1991 .

[6]  P. M. Saunders,et al.  Practical Conversion of Pressure to Depth , 1981 .

[7]  T. Treude,et al.  Scavenger assemblages under differing trophic conditions : a case study in the deep Arabian Sea , 2000 .

[8]  J. Armstrong,et al.  Direct measurement of active dispersal of food-falls by deep-sea demersal fishes , 1991, Nature.

[9]  R. Haedrich,et al.  The megabenthic fauna in the deep sea south of New England, USA , 1980 .

[10]  B. Martin,et al.  Observations on deep-sea benthopelagic nekton at two stations in the northern Arabian Sea: links to organic matter supply? , 2000 .

[11]  Peter Brueggeman,et al.  Deep Sea Ocean Trenches and their Fauna , 1989 .

[12]  T. Wolff.  The concept of the hadal or ultra-abyssal fauna , 1970 .

[13]  A. Milne-edwards,et al.  Crustacés décapodes provenant des campagnes du yacht l'Hirondelle (1886, 1887, 1888) , 1894 .

[14]  J. Poupin.  Crustacea Decapoda and Stromatopoda of French Polynesia , 1998 .

[15]  L. Levin,et al.  Extreme food webs: Foraging strategies and diets of scavenging amphipods from the ocean’s deepest 5 kilometers , 2007 .

[16]  Imants G. Priede,et al.  The fate of cetacean carcasses in the deep sea: observations on consumption rates and succession of scavenging species in the abyssal north-east Atlantic Ocean , 1998, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[17]  R. Gore.  ABYSSOBENTHIC AND ABYSSOPELAGIC PENAEOIDEAN SHRIMP (FAMILIES ARISTEIDAE AND PENAEIDAE) FROM THE VENEZUELA BASIN, CARIBBEAN SEA , 1985 .

[18]  Kenneth L. Smith,et al.  Foraging behavior of abyssal grenadier fish: inferences from acoustic tagging and tracking in the North Pacific Ocean , 1990 .

[19]  A. L. Rice,et al.  Abyssal Megafaunal Necrophages: Latitudinal Differences in the Eastern North Atlantic Ocean , 1995 .

[20]  Torben Wolff,et al.  The hadal community, an introduction , 1959 .

[21]  P. Bagley,et al.  Consumption of large bathyal food fall, a six month study in the NE Atlantic , 2006 .

[22]  T. Platt,et al.  An estimate of global primary production in the ocean from satellite radiometer data , 1995 .

[23]  L. Levin,et al.  Vertical zonation patterns of scavenging amphipods from the Hadal zone of the Tonga and Kermadec Trenches , 2006 .

[24]  Peter Herring,et al.  The Biology of the deep ocean , 2002 .

[25]  P. Bagley,et al.  Baited camera observations of deep-sea demersal fishes of the northeast Atlantic Ocean at 15–28°N off West Africa , 2002 .

[26]  Bryan R. Burnett,et al.  Scavenging amphipods from the floor of the Philippine trench , 1978 .