Krill in the Arctic and the Atlantic – Climatic Variability and Adaptive Capacity –
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Settlement-Driven, Multiscale Demographic Patterns of Large Benthic Decapods in the Gulf of Maine
Journal of Experimental Marine Biology and Ecology, L 241 (1999) 107±136 Settlement-driven, multiscale demographic patterns of large benthic decapods in the Gulf of Maine Alvaro T. Palmaa,* , Robert S. Steneck b , Carl J. Wilson b aDepartamento EcologõaÂÂ, Ponti®cia Universidad Catolica de Chile, Alameda 340, Casilla 114-D, Santiago, Chile bIra C. Darling Marine Center, School of Marine Sciences, University of Maine, Walpole, ME 04573, USA Received 3 November 1998; received in revised form 30 April 1999; accepted 5 May 1999 Abstract Three decapod species in the Gulf of Maine (American lobster Homarus americanus Milne Edwards, 1837, rock crab Cancer irroratus Say, 1817, and Jonah crab Cancer borealis Stimpson, 1859) were investigated to determine how their patterns of settlement and post-settlement abundance varied at different spatial and temporal scales. Spatial scales ranged from centimeters to hundreds of kilometers. Abundances of newly settled and older (sum of several cohorts) individuals were measured at different substrata, depths, sites within and among widely spaced regions, and along estuarine gradients. Temporal scales ranged from weekly censuses of new settlers within a season to inter-annual comparisons of settlement strengths. Over the scales considered here, only lobsters and rock crabs were consistently abundant in their early post- settlement stages. Compared to rock crabs, lobsters settled at lower densities but in speci®c habitats and over a narrower range of conditions. The abundance and distribution of older individuals of both species were, however, similar at all scales. This is consistent with previous observations that, by virtue of high fecundity, rock crabs have high rates of settlement, but do not discriminate among habitats, and suffer high levels of post-settlement mortality relative to lobsters. -
Retail Stores Policies for Marketing of Lobsters in Sardinia (Italy) As Influenced by Different Practices Related to Animal Welf
foods Article Retail Stores Policies for Marketing of Lobsters in Sardinia (Italy) as Influenced by Different Practices Related to Animal Welfare and Product Quality Giuseppe Esposito 1, Daniele Nucera 2 and Domenico Meloni 1,* ID 1 Department of Veterinary Medicine, University of Sassari, Via Vienna 2, 07100 Sassari, Italy; [email protected] 2 Department of Agriculture, Forest and Food Science, University of Turin, Via Verdi 8, 10124 Turin, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-079-229-570; Fax: +39-079-229-458 Received: 12 June 2018; Accepted: 29 June 2018; Published: 2 July 2018 Abstract: The aim of the present study was to evaluate the marketing policies of lobsters as influenced by different practices related to product quality in seven supermarkets located in Italy. Retailers were divided in two categories: large scale and medium scale. The two groups were compared to screen for differences and to assess differences in score distribution attributed to different practices related to product quality. Our results showed no statistical differences (p > 0.05) between the two categories. Lobsters were often marketed alive on ice and/or stocked for long periods in supermarket aquariums, highlighting the need to improve the specific European regulations on health, welfare, and quality at the market stage. Retail shop managers should be encouraged to develop better practices and policies in terms of marketing of lobsters. This will help in keeping the animals in good health and improve product quality at the marketing stages. Keywords: crustaceans; supermarkets; aquarium; ice 1. Introduction In the last decades, the global total consumption of seafood products has increased: this has resulted in a rapidly growing demand for these products, especially in emerging markets [1]. -
Modelling Growth of Northern Krill (Meganyctiphanes Norvegica) Using an Energy-Budget Approach?
Modelling growth of northern krill (Meganyctiphanes norvegica) using an energy-budget approach? Tjalling Jagera,, Elisa Ravagnanb aDEBtox Research, De Bilt, the Netherlands bIRIS Environment, International Research Institute of Stavanger, Postboks 8046, N-4068 Stavanger, Norway Abstract Northern krill (Meganyctiphanes norvegica) is an important species in the North Atlantic and the Mediterranean Sea, but very little life-history infor- mation is available under controlled (laboratory) conditions. Here, we use the DEBkiss model to piece together the available data into a quantitative energy budget. We use this model to analyse larval growth curves, and to re- construct the feeding history for field populations from their (reconstructed) multi-year growth patterns. The resulting model parameters are also used to provide estimates for respiration, feeding and reproduction rates that are consistent with measured values. Many uncertainties remain, but this anal- ysis demonstrates how simple and generic energy-budget models have the potential to integrate observations on different traits, to interpret growth as a function of food and temperature, and to compare different species in a meaningful manner. Keywords: Dynamic Energy Budget, DEBkiss, Meganyctiphanes norvegica, life-history traits, growth modeling, krill ?©2016. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/. The paper was pub- lished as: Jager T, Ravagnan E. 2016. Modelling growth of northern krill (Meganyc- tiphanes norvegica) using an energy-budget approach. Ecological Modelling 325:28-34.. http://dx.doi.org/10.1016/j.ecolmodel.2015.12.020. Email address: [email protected] (Tjalling Jager) URL: http://www.debtox.nl/ (Tjalling Jager) Preprint submitted to Ecological Modelling March 14, 2021 1. -
Fronts in the World Ocean's Large Marine Ecosystems. ICES CM 2007
- 1 - This paper can be freely cited without prior reference to the authors International Council ICES CM 2007/D:21 for the Exploration Theme Session D: Comparative Marine Ecosystem of the Sea (ICES) Structure and Function: Descriptors and Characteristics Fronts in the World Ocean’s Large Marine Ecosystems Igor M. Belkin and Peter C. Cornillon Abstract. Oceanic fronts shape marine ecosystems; therefore front mapping and characterization is one of the most important aspects of physical oceanography. Here we report on the first effort to map and describe all major fronts in the World Ocean’s Large Marine Ecosystems (LMEs). Apart from a geographical review, these fronts are classified according to their origin and physical mechanisms that maintain them. This first-ever zero-order pattern of the LME fronts is based on a unique global frontal data base assembled at the University of Rhode Island. Thermal fronts were automatically derived from 12 years (1985-1996) of twice-daily satellite 9-km resolution global AVHRR SST fields with the Cayula-Cornillon front detection algorithm. These frontal maps serve as guidance in using hydrographic data to explore subsurface thermohaline fronts, whose surface thermal signatures have been mapped from space. Our most recent study of chlorophyll fronts in the Northwest Atlantic from high-resolution 1-km data (Belkin and O’Reilly, 2007) revealed a close spatial association between chlorophyll fronts and SST fronts, suggesting causative links between these two types of fronts. Keywords: Fronts; Large Marine Ecosystems; World Ocean; sea surface temperature. Igor M. Belkin: Graduate School of Oceanography, University of Rhode Island, 215 South Ferry Road, Narragansett, Rhode Island 02882, USA [tel.: +1 401 874 6533, fax: +1 874 6728, email: [email protected]]. -
<I>Cancer Irroratus</I>
BULLETIN OF MARINE SCIENCE, 36(3): 454-466,1985 RHYTHMICITY UNDER CONSTANT CONDITIONS IN THE ROCK CRAB, CANCER IRRORATUS Steve Rebach ABSTRACT The existence of activity rhythms in migratory populations of the rock crab, Cancer ir- roratus, which spend most of the year in deep water, was investigated. Mature individuals from the Mid-Atlantic Bight were tested under laboratory conditions of constant light (LL) and constant dark (DD) after an initial ambient photoperiod was presented. Activity levels were simultaneously monitored for 20 crabs maintained in separate compartments, using an infrared beam-break system. Activity was analyzed using an Enright periodogram. Activity under LL was at a relatively low level and with no rhythmic periodicity exhibited. In DD, activity was concentrated at approximately 25-h intervals, approximating a tidal period. Under ambient (natural photoperiod) conditions, a 24-h rhythm was present with activity greatest during the scotophase and with peaks at dawn and dusk. Possible advantages to the presence of a tidal rhythmicity in a deep water species are discussed and include temporal partitioning of the environment, a timekeeping mechanism for the initiation of migration, and an evolutionary or ecological remnant from shallow water populations. The common rock crab, Cancer irroratus, is found from Labrador to South Carolina (Haefner, 1976) and is most abundant from Maine to North Carolina. Rock crabs inhabit cold water (50-15°C, Haefner, 1976) and in the mid-Atlantic region they live at depths of 10-700 m (depending on age and season), with highest densities between 40 and 60 m (15-30 km offshore) (Musick and McEachran, 1972; Haefner, 1976). -
Diversity and Life-Cycle Analysis of Pacific Ocean Zooplankton by Video Microscopy and DNA Barcoding: Crustacea
Journal of Aquaculture & Marine Biology Research Article Open Access Diversity and life-cycle analysis of Pacific Ocean zooplankton by video microscopy and DNA barcoding: Crustacea Abstract Volume 10 Issue 3 - 2021 Determining the DNA sequencing of a small element in the mitochondrial DNA (DNA Peter Bryant,1 Timothy Arehart2 barcoding) makes it possible to easily identify individuals of different larval stages of 1Department of Developmental and Cell Biology, University of marine crustaceans without the need for laboratory rearing. It can also be used to construct California, USA taxonomic trees, although it is not yet clear to what extent this barcode-based taxonomy 2Crystal Cove Conservancy, Newport Coast, CA, USA reflects more traditional morphological or molecular taxonomy. Collections of zooplankton were made using conventional plankton nets in Newport Bay and the Pacific Ocean near Correspondence: Peter Bryant, Department of Newport Beach, California (Lat. 33.628342, Long. -117.927933) between May 2013 and Developmental and Cell Biology, University of California, USA, January 2020, and individual crustacean specimens were documented by video microscopy. Email Adult crustaceans were collected from solid substrates in the same areas. Specimens were preserved in ethanol and sent to the Canadian Centre for DNA Barcoding at the Received: June 03, 2021 | Published: July 26, 2021 University of Guelph, Ontario, Canada for sequencing of the COI DNA barcode. From 1042 specimens, 544 COI sequences were obtained falling into 199 Barcode Identification Numbers (BINs), of which 76 correspond to recognized species. For 15 species of decapods (Loxorhynchus grandis, Pelia tumida, Pugettia dalli, Metacarcinus anthonyi, Metacarcinus gracilis, Pachygrapsus crassipes, Pleuroncodes planipes, Lophopanopeus sp., Pinnixa franciscana, Pinnixa tubicola, Pagurus longicarpus, Petrolisthes cabrilloi, Portunus xantusii, Hemigrapsus oregonensis, Heptacarpus brevirostris), DNA barcoding allowed the matching of different life-cycle stages (zoea, megalops, adult). -
The Secret Lives of JELLYFISH Long Regarded As Minor Players in Ocean Ecology, Jellyfish Are Actually Important Parts of the Marine Food Web
The secret lives of JELLYFISH Long regarded as minor players in ocean ecology, jellyfish are actually important parts of the marine food web. BY GARRY HAMILTON ennifer Purcell watches intently as the boom of the research ship Moon jellyfish (Aurelia Skookum slowly eases a 3-metre-long plankton net out of Puget Sound aurita) contain more Jnear Olympia, Washington. The marine biologist sports a rain suit, calories than some which seems odd for a sunny day in August until the bottom of the net other jellyfish. is manoeuvred in her direction, its mesh straining from a load of moon jellyfish (Aurelia aurita). Slime drips from the bulging net, and long ten- tacles dangle like a scene from an alien horror film. But it does not bother Purcell, a researcher at Western Washington University’s marine centre in Anacortes. Pushing up her sleeves, she plunges in her hands and begins to count and measure the messy haul with an assuredness borne from nearly 40 years studying these animals. 432 | NATURE | VOL 531 | 24 MARCH 2016 © 2016 Macmillan Publishers Limited. All rights reserved FEATURE NEWS Most marine scientists do not share her enthusiasm for the creatures. also inaccessible, living far out at sea or deep below the light zone. They Purcell has spent much of her career locked in a battle to find funding often live in scattered aggregations that are prone to dramatic popula- and to convince ocean researchers that jellyfish deserve attention. But tion swings, making them difficult to census. Lacking hard parts, they’re she hasn’t had much luck. -
Enormous Carnivores, Microscopic Food, and a Restaurant That's Hard to Find
Enormous Carnivores, Microscopic Food, and a Restaurant That's Hard to Find MARK F. BAUMGARTNER, CHARLES A. MAYO, AND ROBERT D. KENNEY April 1986 Cape Cod Bay We'd known for a long time that there were places east of Cape Cod where pow+l tidal impulses meet the sluggiih southward-moving coastal cur- rent, places where right whales lined up along the rips where plankton con- centrate. On a windless day in early April 1986, we decided to see ifright whales hadfoundsuch an area. The winter season, when right whales come to Cape Cod, had been a hard one, and calm hys like this were few, so we could at last get to the more distant convergence and, as localjshermen do, see what we could catch. It was gloomy and nearly dzrk when we lefi the port. For those of us who study whales, expectations are usually tempered by realip; we were lookingfor one of the rarest of all mammals in the shroud of the ocean. To- day, however, spirits were high as the hybreak was filed with springtime promise. Along the great outer beach of the Cape, so close to shore that we couldsmell the land nearb, thefist right whale was spotted working along one of those current rips. And as the sun climbed out of the haze, the whale rose and opened that great and odd mouth and skimmed the su$ace in a silence broken only ly the sizzle of water passing through its huge filtering Enormous Carnivores, Microscopic Food 139 apparatus. Our earlier optimism was warranted, andfor several hours we drzFedjust clear of the linear rip that the whale was working, recording the complex pattern of its movements. -
Trophic Diversity of Plankton in the Epipelagic and Mesopelagic Layers of the Tropical and Equatorial Atlantic Determined with Stable Isotopes
diversity Article Trophic Diversity of Plankton in the Epipelagic and Mesopelagic Layers of the Tropical and Equatorial Atlantic Determined with Stable Isotopes Antonio Bode 1,* ID and Santiago Hernández-León 2 1 Instituto Español de Oceanografía, Centro Oceanográfico de A Coruña, Apdo 130, 15080 A Coruña, Spain 2 Instituto de Oceanografía y Cambio Global (IOCAG), Universidad de las Palmas de Gran Canaria, Campus de Taliarte, Telde, Gran Canaria, 35214 Islas Canarias, Spain; [email protected] * Correspondence: [email protected]; Tel.: +34-981205362 Received: 30 April 2018; Accepted: 12 June 2018; Published: 13 June 2018 Abstract: Plankton living in the deep ocean either migrate to the surface to feed or feed in situ on other organisms and detritus. Planktonic communities in the upper 800 m of the tropical and equatorial Atlantic were studied using the natural abundance of stable carbon and nitrogen isotopes to identify their food sources and trophic diversity. Seston and zooplankton (>200 µm) samples were collected with Niskin bottles and MOCNESS nets, respectively, in the epipelagic (0–200 m), upper mesopelagic (200–500 m), and lower mesopelagic layers (500–800 m) at 11 stations. Food sources for plankton in the productive zone influenced by the NW African upwelling and the Canary Current were different from those in the oligotrophic tropical and equatorial zones. In the latter, zooplankton collected during the night in the mesopelagic layers was enriched in heavy nitrogen isotopes relative to day samples, supporting the active migration of organisms from deep layers. Isotopic niches showed also zonal differences in size (largest in the north), mean trophic diversity (largest in the tropical zone), food sources, and the number of trophic levels (largest in the equatorial zone). -
The Canary Current Temperatures from Portugal to Cape Most Reliable Indicators
V. Sediments and benthos Rapp. P.-v. Réun. Cons. int. Explor. Mer, 180: 315-322. 1982. Sediments in up welling areas, particularly off Northwest Africa Eugen Seibold Geologisch-Paläontologisches Institut der Universität Kiel Olshausenstrasse 40/60, 2300 Kiel 1, Bundesrepublik Deutschland Introduction Oceanic upwelling supplies water from subsurface lay with sediments, however, most of these variations, ers to the surface layer and may occur as a persistent together with biological production cycles, are aver process anywhere, although it is a particularly con aged out, as even the uppermost centimetre of sedi spicuous phenomenon along western coasts of conti ment normally includes events spanning a century or nents where prevailing winds drive the surface water more. Most of the indicators employed are of organic from the coast (Smith, 1973). origin. It is well established that typical upwelling This paper discusses indicators of coastal upwelling water masses are several degrees cooler than nearby revealed in the underlying sediments off Northwest waters, are less saline, show a relatively low oxygen Africa and makes some comparisons with upwelling content, and have higher nutrient concentrations, effects in sediments from the coastal area off Southwest increasing primary production in the photic zone. At Africa. From these results it will be attempted to present only lowered temperatures as preserved in reconstruct periods of upwelling during the last 20 mil planktonic organisms tests can be used as clear indi lion years off Northwest Africa. Some of these prob cators for upwelling, although higher productivity may lems have been treated generally in the classic paper of provide additional hints. -
Ecological Effects of Predator Information Mediated by Prey Behavior
ECOLOGICAL EFFECTS OF PREDATOR INFORMATION MEDIATED BY PREY BEHAVIOR Tyler C. Wood A Dissertation Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2020 Committee: Paul Moore, Advisor Robert Green Graduate Faculty Representative Shannon Pelini Andrew Turner Daniel Wiegmann ii ABSTRACT Paul Moore, Advisor The interactions between predators and their prey are complex and drive much of what we know about the dynamics of ecological communities. When prey animals are exposed to threatening stimuli from a predator, they respond by altering their morphology, physiology, or behavior to defend themselves or avoid encountering the predator. The non-consumptive effects of predators (NCEs) are costly for prey in terms of energy use and lost opportunities to access resources. Often, the antipredator behaviors of prey impact their foraging behavior which can influence other species in the community; a process known as a behaviorally mediated trophic cascade (BMTC). In this dissertation, predator odor cues were manipulated to explore how prey use predator information to assess threats in their environment and make decisions about resource use. The three studies were based on a tri-trophic interaction involving predatory fish, crayfish as prey, and aquatic plants as the prey’s food. Predator odors were manipulated while the foraging behavior, shelter use, and activity of prey were monitored. The abundances of aquatic plants were also measured to quantify the influence of altered crayfish foraging behavior on plant communities. The first experiment tested the influence of predator odor presence or absence on crayfish behavior. -
EUPHAUSIIDS in the GULF of CALIFORNIA-THE 1957 CRUISES Calcofi Rep., Vol
BRINTON AND TOWNSEND: EUPHAUSIIDS IN THE GULF OF CALIFORNIA-THE 1957 CRUISES CalCOFI Rep., Vol. XXI, 1980 EUPHAUSIIDS IN THE GULF OF CALIFORNIA-THE 1957 CRUISES E. BRINTON AND A.W. TOWNSEND Marine Life Research Group Scripps institution of Oceanography La Jolla. CA 92093 ABSTRACT las especies y de sus etapas de vida, en particular las de Euphasiid crustaceans in the Gulf of California were las larvas mas juveniles, se describen en relacion con las examined from four bimonthly CalCOFI grid cruises variaciones estacionales en el flujo y las temperaturas de during February through August of 1957. Of the nine las aguas del Golfo. species found to regularly inhabit the Gulf, Nematoscelis dificilis and Nyctiphanes simplex are common to the INTRODUCTION warm-temperate California Current. These have the The Gulf of California is inhabited by dense stocks of broadest ranges in the Gulf, peaking in abundance and plankton (Osario-Tafall 1946; Zeitzschel 1969). This reproducing maximally during February-April and Feb- appendix of the North Pacific Ocean communicates. ruary-June respectively, before intense August heating with the 'eastern boundary circulation at the northern limit takes place in the Gulf. Euphausia eximia, a species of the eastern tropical Pacific, which is characterized by having high densities at zones considered marginal to the its distinctive oxygen-deficient layer. The 1 000-km axis eastern tropical Pacific, also varies little in range during of the Gulf extends from the mouth at the tropic, 23"27'N, the year, consistently occupying the southern half of the to latitude 32"N, which is within the belt of the warm- Gulf.