@article{,

title = {Interannual changes in the Sea of Oman ecosystem},

author = {Piontkovski, Sergey A,Al-Gheilani, Hamed MH,Jupp, Barry P,Al-Azri, Adnan R,Al-Hashmi, Khalid A},

year  = {2012},

date = {2012-01-01},

journal = {Open Mar Biol J},

volume = {6},

number = {431},

pages = {38-52},

abstract = {Historical data were used to estimate interannual tendencies for the Sea of Oman over the past 50 years.

Declining trends were shown for the atmospheric surface level pressure in the region affected by the Siberian High

atmospheric anomaly, the zonal component of wind speed, concentration of nitrates, biomass of diatoms and sardine

landings. Changes in Zooplankton biomass showed no clear trend. These trends were associated with and accompanied by

rising atmospheric temperature, sea surface temperature, annual variability of the kinetic energy of mesoscale eddies,

frequency of fish kills (along with the death of other animals- dolphins, turtles, and sea birds) and harmful algal bloom

incidents. In terms of interannual coupling between physical and biological processes, the evaluated trends imply that the

weakening of the Siberian High atmospheric anomaly results in the decline of the zonal wind speed and a regional

increase of air temperature. This in turn increases the temperature in the mixed layer which strengthens thermo-haline

stratification of the water column. Increasing stratification prevents the penetration of nutrients into the mixed layer and

does not favor the interannual increase of biological productivity, although annual variation of biological productivity has

increased, from 1997 to 2008.},

keywords = {Gulf of Oman, Harmful Algal Bloom, Hydro-biology, Interannual variability, mass mortality, oceanography, Sea of Oman, Sultanate of Oman, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Temporal variability of deep-sea zooplankton in the Arabian Sea},

author = {Koppelman,R.,Fabian,H.,Weikert,H.},

year  = {2003},

date = {2003-01-01},

journal = {Marine Biology},

volume = {142},

number = {138},

pages = {959-970},

abstract = {Mesozooplankton samples from two stations in the Arabian Sea (W AST, 4,050 in, 16 degrees 15'N, 60 degrees 20'E; CAST, 3,950 in, 14 degrees 30'N, 64 degrees 30'E) were collected from the surface down to 20 in above bottom during three monsoon periods: the autumn inter-monsoon in October 1995, the spring inter-monsoon in April 1997 , and the NE monsoon in February 1998. The main goal of this study is to enhance our knowledge on the effect of spatial and temporal differences in primary production and particle flux rates on the abundance and distribution of  mesozooplankton, with special attention to the deep sea. Literature data indicate episodically high rates of primary production and particle flux in the region during the sw monsoon and the autumn intermonsoon. Set in this context, the zooplankton showed an in-phase coupling in biomass and abundance with the primary production in the surface 150 in. In the mesopelagic realm (150-1,050 in), the seasonal coupling was less clear. In the bathypelagic zone, below 1 ,050 m, there was no evidence of in-phase coupling, though temporal differences in the distribution of zooplankton abundance and biomass with depth between seasons could be shown by an analysis of covariance and an a posteriori test. The results suggest that the bathypelagic community responds to increased particle flux rates, but with longer time gaps than in the epipelagic zone. This is probably due to longer development and response times of zooplankton in the cold, deep-water environment independent of possible lateral advection processes.},

keywords = {abundance, Arabian Sea, depth, Distribution, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Distribution, annual cycle, and vertical migration of acoustically derived biomass in the Arabian Sea during 1994-1995},

author = {Ashjian,C.J.,Smtih,S.L.,Flagg,C.N.,Idrisi,N.},

year  = {2002},

date = {2002-01-01},

journal = {Deep-Sea Research Part II},

volume = {49},

number = {299},

pages = {2377-2402},

abstract = {The distinguishing characteristic that sets the Arabian Sea apart from other oceanic regions is the regular oscillation of monsoonal atmospheric conditions that produces predictable periods of upwelling or convective mixing, with associated biological response, during the Southwest and Northeast monsoons, respectively. This oscillation is also evident in cycles of standing stocks of zooplankton and micronekton. The vertical distribution and spatial pattern of zooplankton and micronekton biomass were estimated using an acoustic Doppler current profiler along a 1000-km transect extending from the continental shelf of Oman to the central Arabian Sea during ten cruises on the R/V Thomas G. Thompson (November 1994-December 1995). The influence of the Southwest Monsoon, and accompanying upwelling and enhanced acoustically derived biomass, was the dominant feature in the spatial-temporal distributions of both zooplankton and micronekton near the Omani coast. The diel vertical migration of predators (myctophids, pelagic crabs), and the seasonal changes in the strength of this signal, was the most significant pattern observed in the vertical distribution of biomass and imparted a strong day-night signal to the integrated upper water-column biomass. Significant differences in the magnitude of integrated upper water-column biomass, both zooplankton (day) and migrator-zooplankton (night), were seen between inshore and offshore of the atmospheric Findlater Jet. A station located in the central Arabian Sea demonstrated seasonal changes in biomass over the year, despite being quite far from the influence of the monsoonal oscillations. Predation pressure was greater offshore of the Findlater Jet than in the region inshore of the Jet or in the central Arabian Sea. The pelagic community of the Arabian Sea may have evolved life history strategies to coincide with the predictable monsoonal cycle},

keywords = {acoustic, Arabian Sea, diel, Distribution, history, life history, migration, myctophids, Oceanic, Oman, predation, seasonal change, stocks, Upwelling, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Zooplankton spatial distributions in coastal waters of the northern Arabian Sea, August 1995},

author = {Hitchcock,G.L.,Lane,P.,Smith,S.,Luo,J.G.,Ortner,P.B.},

year  = {2002},

date = {2002-01-01},

journal = {Deep-Sea Research Part II},

volume = {49},

number = {387},

pages = {2403-2423},

abstract = {The spatial distribution of zooplankton biomass was surveyed in coastal waters of the northern Arabian Sea during the 1995 Southwest Monsoon (August) on cruise MB 95-06 of the NOAA Ship Malcolm Baldrige.  Vertical patterns of displacement volumes from a limited set of paired day-night MOCNESS tows suggest there was little diel vertical migration in the coastal waters off the southern Arabian Peninsula. Zooplankton biomass varied from 5.2 to 15.1 9 dw m(-2) (178-517mM Cm-2) in the upper 200-300m of Omani coastal waters. Distributions of acoustic backscatter were mapped in eight daytime acoustic Doppler current profiler transects in coastal waters off Oman and Somalia. Several transects contained maxima in acoustic backscatter that coincided with cool, fresh surface features that were several tens of kilometers wide. Although there was considerable scatter in the relationship between acoustically determined biomass (ADB) of zooplankton and surface temperature, there was a trend of increased biomass in the cool surface temperatures of the Omani upwelling zone. Acoustic transects crossed two filaments that extended seaward from upwelling centers off Oman and Somalia. Estimated zooplankton ADB exported from the upwelling zones in the surface features was on the order of 300 kg dw s( -1 ). The physical and biological characteristics of filaments maintain zooplankton associated with upwelling areas, such as Calanoides carinatus, as they are advected offshore from coastal upwelling zones. (C) 2002 Published by Elsevier Science Ltd.},

keywords = {acoustic, Arabian Sea, displacement, Distribution, migration, Oman, surface temperature, temperature, trend, Upwelling, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Understanding the Arabian Sea: Reflections on the 1994-1996 Arabian Sea Expedition},

author = {Smith,S.L.},

year  = {2001},

date = {2001-01-01},

journal = {Deep-Sea Research Part II},

volume = {48},

number = {234},

pages = {1385-1402},

abstract = {The Arabian Sea Expedition, now five years past its field observations, is at a stage when some of its dominant themes can be summarized. Of the large range of possible topics, five are considered here: (1) Is the Arabian Sea a source or sink for carbon dioxide?; (2) Is the Arabian Sea Mother Nature's iron experiment?; (3) Do grazing zooplankton control carbon flux to the seabed?; (4) Does the paleoceanographic record help us predict the ocean's response to climate change?; and (5) What are the predominant physical processes of the Arabian Sea? A short history of each issue and results from the field work of 1994-1996 are presented.},

keywords = {Arabian Sea, history, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Diel vertical migration of zooplankton and mesopelagic fish in the Arabian Sea},

author = {Luo,J.,Ortner,P.B.,Forcucci,D.,Cummings,S.R.},

year  = {2000},

date = {2000-01-01},

journal = {Deep-Sea Research Part II},

volume = {47 },

number = {145},

pages = {1451-1473},

abstract = {Acoustic (153 kHz ADCP and 12 kHz hull-mounted transducers) data and MOCNESS (MOC01 and MOC10) net tow samples collected in the Arabian Sea during the Spring Intermonsoon (April/May) and Southwest Monsoon (August) in 1995 documented substantial diel migrations of fish and zooplankton despite the year-round presence of an oxygen minimum ((0.2 ml l-1 at 125-150 m). Fish and zooplankton layers were distinguished by comparing 12 kHz sonar and 153 kHz ADCP backscatter data, which indicated that the strongly migrating layers were predominantly composed of fishes. Fish vertical migration speeds were independently estimated from the slopes of the volume scattering layers and from the vertical velocity components of the ADCP, yielding average speeds of 4 and 3 cm s-1 and maximum speeds of 13 and 10 cm s-1, respectively. A few migrating zooplankton layers were identified with an average speed of about 2 cm s-1 and maximum speeds as high as 8 cm s-1. Migration depths for both zooplankton and fish differed somewhat amongst stations and appeared to be related to local hydrographic conditions (principally the vertical gradients in DO and water temperature). Zooplankton displacement volumes at individual sites suggested that zooplankton biomass during the Southwest Monsoon could be as much as fivefold greater than during the Spring Intermonsoon. This observation was confirmed for the region in general by first deriving a relationship between ADCP backscatter intensity and daytime zooplankton biomass and then comparing the latter between cruises using daytime ADCP data taken along a 1500 km transect that extended from the coast of Somalia to the center of the northern basin.},

keywords = {acoustic, Arabian Sea, depth, diel, displacement, fish, migration, oxygen minimum, sonar, temperature, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Distribution, abundance, and feeding ecology of decapods in the Arabian Sea, with implications for vertical flux},

author = {Mincks,S.L.,Bollens,S.M.,Madin,L.P.,Horgan,E.,Butler,M.,Kremer,P.M.,Craddock,J.E.},

year  = {2000},

date = {2000-01-01},

journal = {Deep-Sea Research Part II},

volume = {47},

number = {158},

pages = {1475-1516},

abstract = {Macrozooplankton and micronekton samples were collected on two cruises in the Arabian Sea conducted during the Spring Intermonsoon period (May) and the SW Monsoon period (August) of 1995. Discrete depth samples were collected down to depths of 1000-1500 m. Quantitative gut content analyses were performed on four species of decapod shrimps, Gennadas sordidus, Sergia filictum, Sergia creber, and Eupasiphae gilesii, as well as on the pelagic crab Charybdis smithii. Of the shrimps, only S. filictum and S. creber increased significantly in abundance between the Spring Intermonsoon and SW Monsoon seasons. These four species were found at all depths sampled, and most did not appear to be strong vertical migrators. G. sordidus and S. filictum did appear to spread upward at night, especially during the SW Monsoon, but this movement did not include the entire population. S. creber showed signs of diel vertical migration only in some areas. All four shrimp species except, to some degree, S. creber lived almost exclusively within the oxygen minimum zone(150-1000 m), and are likely to have respiratory adaptations that allow them to persist under such conditions. Feeding occurred at all depths throughout these species' ranges, but only modest feeding occurred in the surface layer (0-150 m). G. sordidus appeared to feed continuously throughout the day and night. Estimated contribution of fecal material to vertical flux ranged from < 0.01-2.1% of particulate flux at 1000 m for the shrimps and 1.8-3.0% for C. smithii. (C) 2000 Published by Elsevier Science Ltd. All rights reserved. .},

keywords = {abundance, Arabian Sea, depth, Distribution, ecology, feeding ecology, migration, oxygen minimum, population, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Mezozooplankton production and grazing the Arabian Sea},

author = {Roman,M.,Smith,S.,Wishner,K.,Gowing,M.,Zhang,X.S.},

year  = {2000},

date = {2000-01-01},

journal = {Deep-Sea Research Part II},

volume = {47},

number = {452},

pages = {1423-1450},

abstract = {Growth rates, grazing and fecal pellet production by mesozooplankton size classes in the surface 200 m are compared over two inshore/offshore transects in the Northern Arabian Sea during different monsoon seasons. We derived these rate parameters from measured biomass and several empirical models that estimate copepod production from temperature, body weight and food availability. The multivariate regression published by Hirst and Sheader (1997, Marine Ecology Progress Series, 154, 155-165) gave the most reasonable rate estimates when compared to direct grazing measurements as well as published data on copepod ingestion and growth rates. In general, zooplankton rate estimates were highest at the inshore stations where phytoplankton production and zooplankton biomass were maximum. Overall cruise means of zooplankton biomass and rate estimates during the early and late NE Monsoon, Spring Inter-monsoon and SW Monsoon were not significantly different. The estimated zooplankton community (all size fractions) growth rate averaged 0.12d(-I) over all stations during the different monsoon seasons. Although smaller zooplankton size fractions grew faster, slower growing > 2 mm zooplankton dominated the zooplankton biomass of the Arabian Sea and this resulted in a lower overall community growth rate. Estimated total carbon (phytoplankton, protozoa and detritus) ingestion averaged 44 mM C m(-2) d(-I), which was approximately 40% of primary production, Expressed as a percentage ofbiomass, we found that zooplankton ingested approximately 400/0 of their body carbon d( -1 ). Zooplankton fecal pellet production averaged 13 mM C m(-2) d(-I) or roughly 12% of primary production. This estimated fecal pellet production was greater than measurements of the export flux during the NE Monsoon and Spring Intermonsoon. However, estimated fecal pellet production was less than measured export flux during the SW Monsoon when sinking phytoplankton likely contributed directly to the export flux. Our data suggest that relative to other ocean basins, the grazing impact of mesozooplankton is significant in the Arabian Sea as a consequence of the high zooplankton biomass, abundance of diatoms, and warm temperatures, which result in high zooplankton metabolic demands and growth rates. The observation that the average zooplankton biomass ( 110 mM C m( -2¯) did not change significantly over the monsoon seasons suggests that zooplankton production (13 mM C m(-2) d(-I)) and zooplankton mortality were similar over the study interval. (C) 2000 Elsevier Science Ltd. All rights reserved.},

keywords = {abundance, Arabian Sea, ecology, marine, mortality, multivariate, temperature, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {The Northeast Monsoon's impact on mixing, phytoplankton biomass and nutrient cycling in the Arabian Sea},

author = {Wiggert,J.D.,Jones,B.H.,Dickey,T.D.,Brink,K.H.,Weller,R.A.,Marra,J.,Codispoti,L.A.},

year  = {2000},

date = {2000-01-01},

journal = {Deep-Sea Research Part II},

volume = {47},

number = {254},

pages = {1353-1385},

abstract = {In the northern Arabian Sea, atmospheric conditions during the Northeast (winter) Monsoon lead to deep convective mixing. Due to the proximity of the permanent pycnocline to the sea surface, this mixing does not penetrate below 125 m. However, a strong nitracline is also present and the deep convection results in significant nitrate flux into the surface waters. This leads to nitrate concentrations over the upper 100 m that exceed 4 æM toward the end of the monsoon. During the 1994/1995 US JGOFS/Arabian Sea expedition, the mean areal gross primary production over two successive Northeast Monsoons was determined to be 1.35 gC/m2/d. Thus, despite the deep penetrative convection, high rates of primary productivity were maintained. An interdisciplinary model was developed to elucidate the biogeochemical processes involved in supporting the elevated productivity. This model consisted of a 1-D mixed-layer model coupled to a set of equations that tracked phytoplankton growth and the concentration of the two major nutrients (nitrate and ammonium). Zooplankton grazing was parameterized by a rate constant determined by shipboard experiments. Model boundary conditions consist of meteorological time-series measured from the surface buoy that was part of the ONR Arabian Sea Experiment's central mooring. Our numerical experiments show that elevated surface evaporation, and the associated salinization of the mixed layer, strongly contributes to the frequency and penetration depth of the observed convective mixing. Cooler surface temperatures, increased nitrate entrainment, reduced water column stratification, and lower near-surface chlorophyll a concentrations all result from this enhanced mixing. The model also captured a dependence on regenerated nitrogen observed in nutrient uptake experiments performed during the Northeast Monsoon. Our numerical experiments also indicate that variability in mean pycnocline depth causes up to a 25% reduction in areal chlorophyll a concentration. We hypothesize that such shifts in pycnocline depth may contribute to the interannual variations in primary production and surface chlorophyll a concentration that have been previously observed in this region.},

keywords = {Arabian Sea, chlorophyll, depth, growth, impact, lead, productivity, surface temperature, temperature, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {The oxygen minimum zone in the Arabian Sea during 1995},

author = {Morrison,J.M.,Codispoti,L.A.,Smith,S.L.,Wishner,K.,Flagg,C.,Gardner,W.D.,Gaurin,S.,Naqvi,S.W.A.,Manghnani,V.,Prosperie,L.,Gundersen,J.S.},

year  = {1999},

date = {1999-01-01},

journal = {Deep-Sea Research Part II},

volume = {46},

number = {174},

pages = {1903-1931},

abstract = {This paper focuses on the characteristics of the oxygen minimum zone (OMZ) as observed in the Arabian Sea over the complete monsoon cycle of 1995. Dissolved oxygen, nitrite, nitrate and density values are used to delineate the OMZ, as well as identify regions where denitrification is observed. The suboxic conditions within the northern Arabian Sea are documented, as well as biological and chemical consequences of this phenomenon. Overall, the conditions found in the suboxic portion of the water column in the Arabian Sea were not greatly different from what has been reported in the literature with respect to oxygen, nitrate and nitrite distributions. Within the main thermocline, portions of the OMZ were found that were suboxic (oxygen less than ~4.5 æM) and contained secondary nitrite maxima with concentrations that sometimes exceeded 6.0 æM, suggesting active nitrate reduction and denitrification. Although there may have been a reduction in the degree of suboxia during the Southwest monsoon, a dramatic seasonality was not observed, as has been suggested by some previous work. In particular, there was not much evidence for the occurrence of secondary nitrite maxima in waters with oxygen concentrations greater than 4.5 æM. Waters in the northern Arabian Sea appear to accumulate larger nitrate deficits due to longer residence times even though the denitrification rate might be lower, as evident in the reduced nitrite concentrations in the northern part of the basin. Organism distributions showed string relationships to the oxygen profiles, especially in locations where the OMZ was pronounced, but the biological responses to the OMZ varied with type of organism. The regional extent of intermediate nepheloid layers in our data corresponds well with the region of the secondary nitrite maximum. This is a region of denitrification, and the presence and activities of bacteria are assumed to cause the increase in particles. ADCP acoustic backscatter measurements show diel vertical migration of plankton or nekton and movement into the OMZ. Daytime acoustic returns from depth were strong, and the dawn sinking and dusk rise of the fauna were obvious. However, at night the biomass remaining in the suboxic zone was so low that no ADCP signal was detectable at these depths. There are at least two groups of organisms, one that stays in the upper mixed layer and another that makes daily excursions. A subsurface zooplankton peak in the lower OMZ (near the lower 4.5 æM oxycline) was also typically present; these animals occurred day and night and did not vertically migrate.},

keywords = {acoustic, Arabian Sea, density, depth, diel, Distribution, location, migrate, migration, occurrence, oxygen minimum, plankton, thermocline, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Feeding ecology of the copepod},

author = {Gowing,M.M.,Wishner,K.F.},

year  = {1998},

date = {1998-01-01},

journal = {Deep-Sea Research Part II},

volume = {45 },

number = {105},

pages = {2433},

abstract = {Feeding ecology of the calanoid copepod Lucicutia aff. L. grandis collected in the Arabian Sea at one station during the Spring Intermonsoon and during the Southwest Monsoon of 1995 was studied with transmission electron microscopy of gut-contents. Highest abundances of these animals occurred from 400 to 1100 m, near the lower interface of the oxygen minimum zone and at the inflection point where oxygen starts to increase. We expected that their gut-contents would include particles and cells that had sunk relatively undegraded from surface waters as well as those from within the oxygen minimum zone, and that gut-contents would differ between the Spring Intermonsoon and the more productive SW Monsoon. Overall, in both seasons Lucicutia aff. L. grandis was omnivorous, and consumed a variety of detrital particles, prokaryotic and eukaryotic autotrophs, gram-negative bacteria including metal-precipitating bacteria, aggregates of probable gram-positive bacteria, microheterotrophs, virus-like particles and large virus-like particles, as well as cuticle and cnidarian tissue. Few significant differences in types of food consumed were seen among life stages within or among various depth zones. Amorphous, unidentifiable material was significantly more abundant in guts during the Spring Intermonsoon than during the late SW Monsoon, and recognizable cells made up a significantly higher portion of gut-contents during the late SW Monsoon. This is consistent with the Intermonsoon as a time when organic material is considerably re-worked by the surface water microbial loop before leaving the euphotic zone. In both seasons Lucicutia aff. L. grandis had consumed what appeared to be aggregates of probable gram-positive bacteria, similar to those we had previously found in gut-contents of several species of zooplankton from the oxygen minimum zone in the eastern tropical Pacific. By intercepting sinking material, populations of Lucicutia aff. L. grandis act as a filter for carbon sinking to the sea floor. They also},

keywords = {abundance, Arabian Sea, depth, eastern tropical Pacific, ecology, feeding ecology, oxygen minimum, population, populations, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Seasonal response of zooplankton to monsoonal reversals in the Arabian Sea},

author = {Smith,S.,Roman,M.,Prusova,I.,Wishner,K.,Gowing,M.,Codispoti,L.A.,Barber,R.,Marra,J.,Flagg,C.},

year  = {1998},

date = {1998-01-01},

journal = {Deep-Sea Research Part II},

volume = {45},

number = {478},

pages = {2369-2403},

abstract = {The US JGOFS Arabian Sea Process Study was designed to provide a seasonally and spatially resolved carbon budget for a basin exhibiting some of the highest and lowest concentrations of plant biomass in the world's ocean. During the US JGOFS Process Study in the Arabian Sea (September 1994-January 1996), the absolute maximum in biomass of epipelagic zooplankton in the entire study was observed during the Southwest Monsoon season inshore of the Findlater Jet in the area of upwelling. The greatest contrast between high and low biomass in the study area also was observed during the Southwest Monsoon, as was the strongest onshore-offshore gradient in biomass. Lowest biomass throughout the study was observed at the most offshore station (SI5), outside the direct influence of the monsoon forcing. The greatest day/night contrastsing biomass were observed nearshore in all seasons, with nighttime biornass-exceeding daytime in the Northeast Monsoon season, but daytime exceeding nighttime in the Southwest Monsoon season. The diel vertical migration patterns in general reversed between the monsoons at all stations in the southern part of the study area. Virtually, no diel vertical migration of zooplankton took place in any season at the station with strong, persistent subsurface suboxic conditions (N7), suggesting that these conditions suppress migration. Based on the distribution of biomass, we hypothesize that inshore of the Findlater Jet, zooplankton grazing on phytoplankton is the dominant pathway of carbon transformation during both monsoon seasons, whereas offshore the zooplankton feed primarily on microplankton or are carnivorous, conditions that result in reduction of the carbon flux mediated by the zooplankton. Predation by mesopelagic fish., primarily myctophids, may equal daily growth of zooplankton inshore of the Findlater Jet during all seasons. This suggests that the food web inshore of the Findlater Jet is well integrated, may have evolved during past periods of intensified upwelling, and has a distinctly annual cycle. (C) 1998 Elsevier Science Ltd. All rights reserved.},

keywords = {Arabian Sea, Distribution, migration, predation, Upwelling, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {The 1994-1996 Arabian Sea Expedition: An integrated, interdisciplinary investigation of the resonse of the northwestern Indian Ocean to monsoonal forcing},

author = {Smith,S.L.,Codispoti,L.A.,Morrison,J.M.,Barber,R.},

year  = {1998},

date = {1998-01-01},

journal = {Deep-Sea Research Part II},

volume = {45},

number = {235},

pages = {1905-1915},

abstract = {This document outlines the aims and methodology used in the JGOFS cruise and reports some of the initial results.  Relevant quotes:  The response of hte Arabian Sea to sustained southwest winds of high intesity during hte summer is clear and direct.  TEH area of upwelling, identified by cool sst observed by the AVHRR images increases markedly form early to mid-june and remins in this configuration with variability assocated with changes in wind strength until mid-September.  Once thew SW monsoon winds relax in id september, the upwelling may collapse quickly.  Although the mean wind strenght is much lower, the situation is more or less reversed during hte winter months when cool, dry winds associated with the NE monsoon blow over hte ARabian SEa.},

keywords = {Arabian Sea, history, Indian Ocean, Upwelling, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Spatial distribution of Euphausiacea (Crustacea) in the southeastern Arabian Sea},

author = {Silas,E.G.,Matthew,K.J.},

year  = {1986},

date = {1986-01-01},

journal = {Journal of the Marine Biological Association of India},

volume = {28},

number = {230},

pages = {1-21},

abstract = {Spatial distribution of euphausiids of the southeastern Arabian Sea (west coast of India including the Lakshadweep Sea) was studied. The Arabian Sea and the Bay of Bengal, closed at their northern parts, present special hydrographical features which influence the distribution and abundance of zooplankton in these areas. Here the l0 degree N latitude is thought to be an effective barrier against he penetration of several oceanic species of euphausiids northwards.  This is because of the significant changes in the water quality of N of 10 degree N being influenced by the discharge from major river systems of the Indian sub-continent.  The species Thysanopoda monacantha, T. tricuspidata and Stylocheiron maximum, which were believed to be restricted to areas south of 10 degrees N are distributed even further northwards.},

keywords = {abundance, Arabian Sea, Distribution, Euphausiid, India, Oceanic, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Euphausiids of the Indian Ocean and the Red Sea (original title Ehvfauziidy Indijskogo okeana I krasnogo morya)},

author = {Ponomareva,L.A.},

year  = {1975},

date = {1975-01-01},

journal = {Nauka},

volume = {1},

number = {197},

abstract = {The study is mainly based on euphausiid material from 2390 plankton samples collected in the Indian Ocean during Oct-March 1959/60 and 1960/61. Data are presented on the sp composition, biology, vertical and quantitative distribution. The northern Indian Ocean (as far south as 40 degree S) is inhabited by typically tropical euphausiid fauna. The area most rich in euphausiids is the Arabian Sea. The spp most commonly occurring in the 0-200m layer in the Indian Ocean are Euphausia diomedeae, E. distinguenda, Stylocheiron carinatum and Thysanopoda tricuspidata. In the northern Indian Ocean eggs an early larval stages occurred from Jan to June (no observations were made later in the yr), which suggests that euphausiids spawn several times during the yr. The eggs develop very rapidly (within <24h) and so do early larval stages. On reaching the nauplius-2 stage the development slows down and it takes the larva 10-12 days to develop into furcilia-1. The feeding is varied and mixed: none of the spp were observed to feed on phyto- or zooplankton exclusively. Migratory spp show diurnal feeding rhythms. Most of the spp occurring in the upper layers ( down to 500m) are distinct migrants; interzonal spp do not perform significant migrations rarely rising close to the surface and almost never occurring above 50-40m.  The Red Sea is inhabited by immigrants from teh Gulf of Aden and by some endemic spp. The spp abundant in the Arabian Sea are also predominant here with the addition of S. affine. },

keywords = {Arabian Sea, biology, Distribution, Euphausiid, feeding, Indian Ocean, migration, plankton, Red Sea, zooplankton},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {On the ecology and feeding habits of the euphausiids (Crustacea) in the Arabian Sea (Zur Okologie und Eranhrungsbiologie der Euphausiaceen (Crustacea) im Arabischen Meer)},

author = {Weigmann,R.},

year  = {1970},

date = {1970-01-01},

journal = {Meteor Forschungsergeb.},

volume = {5},

number = {498},

pages = {11-52},

abstract = {In the present paper, the ecology and feeding habits of euphausiids are described. The samples were taken at the time of the NE-monsoon (1964/65) by R. V. 'Meteor' in the Arabian Sea and adjacent waters. 24 spp were determined. According to distribution of the spp, the following marine areas can be distinguished: Arabian Sea: 24 spp, dominant are Euphausia diomedeae, E. tenera, E. distinguenda,  Stylocheiron carinatum. Gulf of Aden: 1 0 spp, dominant are Euphausia diomedeae, E. distinguenda.  Red Sea: 6 spp, dominant are Euphausia diomedeae, E. distinguena. Gulf of Oman: 5 spp, dominant are Euphausia distinguenda, Pseudeuphausia latifrons. Persian Gulf: 1 sp- Pseudeuphausia latifrons. The total number of euphausiids indicate the biomass of this group. High densities of euphausiids (200-299 and > 300 individuals/l00 m super(3)) occur in the innermost part of  the Gulf of Aden, in the area south of the Euqator near the African east coast, near Karachi (Indian west coast) and in the Persian Gulf.   Comparison with data relating to production biology confirms that these are eutrophic zones which coincide with areas in which upwelling occurs at the time of the NE-monsoon. The central part of the Arabian Sea differs from adjacent waters by virtue of less dense euphasiid populations (>199 individuals/lOO m super(3)). Measurements relating to production biology demonstrate a relatively low concentration of primary food sources. Food material was ascertained by analysis of stomach content. The following omnivorous species were examined: Euphausia diomedeae, E. distinguenda, E. tenera, Pseudeuphausia latifronts and Thysanopoda tricuspidata. Apart from crustacean remains large numbers  of Foraminifera, Radiolaria, tintinnids, dinoflagellates were found in the stomachs. Quantitatively crustaceans form the most important item in the diet. Food selection on the basis of size an form appears to be restricted to certain genera of tintinnids. The genera Stylocheiron and Nematoscelis are predators. Only crustacean remains were found in the stomachs of Stylocheiron abbreviatum, whereas Radiolaria, Foraminifera and tintinnids occurred to some extent in Nematoscelis sp. Different euphauisiids occupy different positions in the food chain in the Arabian Sea. In omnivorous species the position is variable, since they not only feed by filtering autotrophic and heterotrophic Protista, but also by predation on zooplankton. Carnivorous spp without filtering apparatus feed exclusively on zooolankton of the size of copepods. Only these spp are well established as occupying a higher position in food chain. The parasrtlc protozoan Thalassomyces fagei was found on Euphausia diomedeae, E. tenera, E. distinguenda and E. sanzoi.},

keywords = {Arabian Sea, biology, density, diet, Distribution, ecology, Euphausiid, feeding, Gulf of Aden, Gulf of Oman, marine, Oman, population, populations, predation, Red Sea, Upwelling, zooplankton},

pubstate = {published},

tppubtype = {article}

}