West Atlantic Research Articles

Southward Displacement of the North Atlantic Subtropical Gyre Circulation System During North Atlantic Cold Spells

AbstractDuring times of deglacial Atlantic Meridional Overturning Circulation (AMOC) perturbations, the tropical Atlantic experienced considerable warming at subsurface levels. Coupled ocean‐atmosphere simulations corroborate the tight teleconnection between the tropical Atlantic and climate change at high northern latitudes but still underestimate the relevance of the subsurface North Atlantic subtropical gyre (STG) for heat and salt storage and its sensitivity to rapid climatic change. We here reconstruct vertical and lateral temperature and salinity gradients in the tropical west Atlantic and the Caribbean over the last 30 kyr, based on planktic deep and shallow dwelling foraminiferal Mg/Ca and δ18O records. The rapid and large‐amplitude subsurface changes illustrate a dynamic STG associated with abrupt shifts of North Atlantic hydrographic and atmospheric regimes. During full glacial conditions, the STG has been shifted southward while intensified Ekman downwelling associated to strengthened trade winds fostered the formation of warm and saline salinity maximum water (SMW). The southward propagation of SMW was facilitated by the glacially eastward deflected North Brazil Current. During periods of significant AMOC perturbations (Heinrich Stadials 1 and the Younger Dryas), extreme subsurface warming by ~6 °C led to diminished lateral subsurface temperature gradients. Coevally, a deep thermocline suggests that SMW fully occupied the subsurface tropical west Atlantic and that the STG reached its southernmost position. During the Holocene, modern‐like conditions gradually developed with the northward retreat of SMW and the development of a strong thermocline ridge between the Subtropical Gyre and the tropical west Atlantic.

A New Species of Serranids of Genus Pseudogramma from the Indian Ocean (Serranidae)

The new species Pseudogramma cernunnos sp. n., which is close to West Atlantic P. gregoryi and South Pacific P. australis (Easter Island) and P. xantha (Polynesia) but differing by pattern on the head and several meristic and plastic characters, is described from the Bay of Bengal near the Andaman Islands. The new finding fills the gap between distribution ranges of the previously known species of this complex and indicates possible ways for distribution of these species.

Between the Atlantic West and the Newest Chinese East: Preliminary Remarks About Central-Eastern European Legal Orders and Their Protection of Civil Liberties and Religious Freedom

Between the Atlantic West and the Newest Chinese East: Preliminary Remarks About Central-Eastern European Legal Orders and Their Protection of Civil Liberties and Religious Freedom

Holocene succession patterns of land snails across temperate Europe: East to west variation related to glacial refugia, climate and human impact

Although Holocene mollusc succession has been described from many temperate European sites, no attempt to analyse diversity patterns across the continent from east to west has yet been done. Here, we assembled and quantitatively analysed 54 most representative Holocene successions categorized into five climatic and geomorphological regions. These were defined along a longitudinal transect across temperate Europe, i.e. West Carpathians, Bohemian Massif, West Continental, Atlantic France, and Atlantic England. We found a clear east-west gradient in the Holocene dynamic of land snail assemblages, correlating mainly with the changes in strictly forest species richness. Representation of these species increased towards the east in accordance with known position of glacial refugia in the Carpathian Mountains. The West Carpathians acted as a unique refugium, expressing the highest temporal stability of Holocene snail assemblages, with a sharp increase in strictly forest species richness already in the Early Holocene. In contrast, Atlantic regions, characterized by low elevation and low topographical heterogeneity, were always poor in number of strictly forest species with no or only shallow increase of their richness in the Holocene climatic optimum. Further reduction in the second half of the Holocene, along with the increase of strictly open-country species richness correlates with higher human impact on mollusc faunas in lowland and flat regions. These factors can explain the previously reported impoverishment of modern western European forest fauna and have apparently also contributed to regional diversity patterns throughout the Holocene. Among the regions, we found three types of successional trajectories in the composition changes of Holocene molluscs, mirroring the above mentioned east-west gradient, with the West Carpathians having the most distinctive fauna. Our results show that distance from glacial refugia, landscape topography, and also human impact importantly shaped the species richness dynamic and successional pathways of Holocene land-snail fauna across temperate Europe.

Leading modes of interannual soil moisture variability in European Russia and their relation to regional climate during the summer season

Soil moisture (SM) data from the Global Land Evaporation Amsterdam Model dataset for 1980–2014 are used to investigate interannual variability of SM in European Russia during the summer season. An Empirical Orthogonal Function (EOF) analysis performed on monthly-mean data (i.e., separately for June, July and August) revealed three leading modes of SM variability, characterized by monopole (EOF-1), zonal dipole (EOF-2) and meridional dipole (EOF-3) patterns. Together these modes explain more than half of the total SM variability in each summer month. Analysis of correlations between the leading PCs (principal components) of SM in European Russia and indices of regional teleconnections suggests that the monopole pattern is associated with the Polar—Eurasia teleconnection, whereas the zonal and meridional dipole patterns are linked respectively to the East Atlantic—West Russia and Scandinavian teleconnections. These links are subject to change over the summer season. The leading PCs broadly capture the large SM anomalies associated with regional climate extremes (such as the Russian summer heat wave in 2010). Correlation analysis revealed generally consistent patterns in which positive (negative) SM anomalies are linked to cyclonic (anti-cyclonic) anomalies of sea level pressure, above (below) normal precipitation and negative (positive) anomalies of air temperature. Locally we find differing roles of air temperature and precipitation in land-atmosphere interaction. Specifically, while precipitation is the dominant driver of interannual SM variability in early summer, air temperature plays a larger role in late-summer land-atmosphere interaction (at some time scales) over the southern part of European Russia, where moisture availability is limited.

Diversity of zoantharian species and their symbionts from the Macaronesian and Cape Verde ecoregions demonstrates their widespread distribution in the Atlantic Ocean

Zooxanthellate zoantharians (Cnidaria: Anthozoa) are commonly found in tropical and subtropical marine regions around the world. However, due to the low genetic variability of commonly used DNA markers combined with high levels of intraspecific morphological variation, misidentifications and species synonyms are commonly found in the literature. In this study, zoantharians from the suborder Brachycnemina collected in the Macaronesia and Cape Verde ecoregions were studied combining morphological, molecular and ecological data, in order to comprehensively assess the species diversity of the region. Moreover, molecular analyses of endosymbiotic Symbiodiniaceae zooxanthellae were also performed to provide more information on each holobiont. Our integrative results demonstrate that Brachycnemina species diversity increases as seawater temperature rises toward the tropics with a total of nine species recorded: one from waters around northern Madeira, five in the Canary Islands and seven in the southernmost Cape Verde Archipelago. All species were seen to host either Symbiodiniaceae of the genera Symbiodinium (former Symbiodinium ‘Clade A’) or Cladocopium (former Symbiodinium ‘Clade C’). Moreover, this study records for the first time the presence of Palythoa grandis, P. aff. clavata, P. grandiflora, an unknown Zoanthus species and Z. pulchellus in the East Atlantic Ocean. These results show no endemic zooxanthellate zoantharians in the East Atlantic, with all species shared with the West Atlantic.

Comparing cnidocyst sizes among populations of Bunodosoma (Cnidaria: Actiniaria: Actiniidae) from the South Atlantic west coast

The simplicity of a sea anemone polyp hinders the differences between species and populations, as very few external and internal morphological characters vary enough to distinguish closely related groups. Variations in size of different cnidocyst types could be an important way to characterize populations of sea anemones. We aim to identify which cnidocyst types could be useful to distinguish the variation between sea anemone populations, tested for two species of genus Bunodosoma from the South Atlantic west coast: Bunodosoma caissarum from the Brazilian coast, and Bunodosoma cangicum from the Brazilian and Uruguayan coasts. We measured cnidocysts in several parts of the sea anemones: acrorhagi, external and internal tentacles, column, actinopharynx and filaments, comprising a total of 35,593 measured capsules. Comparisons between cnidocysts lengths from each tissue type were performed by Generalized Linear Models. In B. caissarum, basitrichs from external and internal tentacles were found to be useful for detecting differences between populations and may indicate a latitudinal gradient. For B. cangicum, these aspects should be further analyzed in basitrichs from external tentacles, holotrichs from acrorhagi and microbasic b-mastigophores from the filaments. The basitrich from tentacles were found to be the most informative cnidae type in both species for population studies in a latitudinal sense.

Revision of the amphiamerican genus Mysidium Dana, 1852 (Crustacea: Mysida: Mysidae), with descriptions of two new species and the establishment of two new subgenera

Revised definitions are given for the genus Mysidium Dana, 1852, and its eight previously known species, based on material from Curaçao, Bonaire and SE-Brazil, along with the evaluation of published data. Type material of Diamysis columbiae Zimmer, 1915, M. cubanense Băcescu & Ortiz, 1984 and M. rubroculatum Băcescu & Ortiz, 1984 is examined. A lectotype is designated for D. columbiae Zimmer, 1915, a senior synonym of Mysidium columbiae (Zimmer, 1915). Two new species are described, M. triangulare Wittmann sp. nov. from Curaçao and M. antillarum Wittmann sp. nov. from Curaçao and Bonaire. Known ranges are extended by first records of M. cubanense from Curaçao and Bonaire and of M. integrum W.M. Tattersall, 1951 from SE Brazil. Three morphologically different groups are established at the subgeneric level: (1) the nominotypical subgenus Mysidium Dana, 1852 with M. gracile (Dana, 1852), M. integrum, M. cubanense, M. rubroculatum and M. triangulare sp. nov. from the West Atlantic plus M. rickettsi Harrison & Bowman, 1987 from the East Pacific; (2) Occimysidium Wittmann subgen. nov. represented only by M. pumae Ortiz, Hendrickx & Winfield, 2017 from the Pacific coast of Mexico; and finally (3) Orientomysidium Wittmann subgen. nov. comprising M. columbiae and M. antillarum sp. nov. from the West Atlantic. The poorly known M. iliffei Băcescu, 1991 is not assigned to any subgenus. A key to the resulting three subgenera and ten nominal species of the genus Mysidium is given.

New insights on the dissolved platinum behavior in the Atlantic Ocean

The water column profiles of dissolved Pt were determined in samples taken during the GEOTRACES GA02 section at three stations located in the North, Central and South West Atlantic Ocean. Average concentrations obtained in this study for dissolved Pt (0.22 ± 0.04 pM; n = 59) are in agreement with the only previous dataset for the Atlantic Ocean reported in the early nineties. However, results presented here do not show invariant concentrations with depth as previously indicated for the Atlantic and recently reported for the Pacific Ocean. Instead, these new data suggests that (i) atmospheric inputs can account for the observed Pt enrichment in surface waters of the North West Atlantic; (ii) conservative mixing control the Pt distribution in deep (>1000 m) waters; and (iii) oxygen may play a major role on the Pt distribution in the oceans, since similar trends of Pt with dissolved oxygen were observed with Pt depletion at water depths of maximum oxygen utilization. There is still, however, important open questions on the (bio)geochemistry of Pt in natural waters including the redox behavior of the Pt(II)/Pt(IV) couple and its impact on particle (inorganic and/or biogenic) reactivity, which impedes a better characterization of the observed distribution in this study. Also, potential analytical artifacts that could be behind the differences in the Pt distributions observed for the different ocean basins must be further explored.This article is part of a special issue entitled: “Cycles of trace elements and isotopes in the ocean – GEOTRACES and beyond” - edited by Tim M. Conway, Tristan Horner, Yves Plancherel, and Aridane G. González.

The mitochondrial genome of a slit limpet Pseudorimula sp. (Vetigastropoda: Lepetodrilidae) from hydrothermal vent on the Southwest Indian Ridge

Pseudorimula is a vent-endemic genus found at some hydrothermal vents in West Pacific, North Atlantic, and Indian oceans. Here, we report a nearly complete mitogenome of Pseudorimula sp. (Vetigastropoda, Lepetodriloidea, Lepetodrilidae), which is collected from Tiancheng vent field on the Southwest Indian Ridge. The genome is 16,682 in length, including 13 complete protein-coding genes, two rRNA genes, and 22 tRNA genes. All genes are arranged in the same order as that in the genus Lepetodrilus, revealing a potential conserved gene arrangement in the family Lepetodrilidae. The phylogenetic analysis shows that the Pseudorimula+Lepetodrilus clade is well supported.

Subseasonal Variability of Rossby Wave Breaking and Impacts on Tropical Cyclones during the North Atlantic Warm Season

AbstractThis study investigates the subseasonal variability of anticyclonic Rossby wave breaking (AWB) and its impacts on atmospheric circulations and tropical cyclones (TCs) over the North Atlantic in the warm season from 1985 to 2013. Significant anomalies in sea level pressure, tropospheric wind, and humidity fields are found over the tropical–subtropical Atlantic within 8 days of an AWB activity peak. Such anomalies may lead to suppressed TC activity on the subseasonal time scale, but a significant negative correlation between the subseasonal variability of AWB and Atlantic basinwide TC activity does not exist every year, likely due to the modulation of TCs by other factors. It is also found that AWB occurrence may be modulated by the Madden–Julian oscillation (MJO). In particular, AWB occurrence over the tropical–subtropical west Atlantic is reduced in phases 2 and 3 and enhanced in phases 6 and 7 based on the Real-Time Multivariate MJO (RMM) index. The impacts of AWB on the predictive skill of Atlantic TCs are examined using the Global Ensemble Forecasting System (GEFS) reforecasts with a forecast lead time up to 2 weeks. The hit rate of tropical cyclogenesis during active AWB episodes is lower than the long-term-mean hit rate, and the GEFS is less skillful in capturing the variations of weekly TC activity during the years of enhanced AWB activity. The lower predictability of TCs is consistent with the lower predictability of environmental variables (such as vertical wind shear, moisture, and low-level vorticity) under the extratropical influence.

Genetic and phenotypic differentiation of lumpfish (Cyclopterus lumpus) across the North Atlantic: implications for conservation and aquaculture.

Demand for lumpfish (Cyclopterus lumpus) has increased exponentially over the last decade, both for their roe, which is used as a caviar substitute, and increasingly also as cleaner fish to control sea lice in salmon farming. The species is classified as Near Threatened by the IUCN and there are growing concerns that over-exploitation of wild stocks and translocation of hatchery-reared lumpfish may compromise the genetic diversity of native populations. We carried out a comparative analysis of genetic and phenotypic variation across the species’ range to estimate the level of genetic and phenotypic differentiation, and determined patterns of gene flow at spatial scales relevant to management. We found five genetically distinct groups located in the West Atlantic (USA and Canada), Mid Atlantic (Iceland), East Atlantic (Faroe Islands, Ireland, Scotland, Norway and Denmark), English Channel (England) and Baltic Sea (Sweden). Significant phenotypic differences were also found, with Baltic lumpfish growing more slowly, attaining a higher condition factor and maturing at a smaller size than North Atlantic lumpfish. Estimates of effective population size were consistently low across the North East Atlantic (Iceland, Faroe Islands and Norway), the area where most wild lumpfish are fished for their roe, and also for the aquaculture industry. Our study suggests that some lumpfish populations are very small and have low genetic diversity, which makes them particularly vulnerable to over-exploitation and genetic introgression. To protect them we advocate curtailing fishing effort, closing the breeding cycle of the species in captivity to reduce dependence on wild stocks, restricting the translocation of genetically distinct populations, and limiting the risk of farm escapes.

High photosynthetic rates associated with pico and nanophytoplankton communities and high stratification index in the North West Atlantic

The biological dynamics of pelagic marine ecosystems are strongly influenced by the size structure and ecological succession of phytoplankton, which in turn modifies photosynthetic efficiency. Variability in photosynthetic rates is closely coupled with changes in community structure, but it is difficult to obtain coincident data at high enough resolution to characterise these changes. In this study, we employ hierarchical cluster analysis on chlorophyll-normalised high performance liquid chromatography (HPLC) pigment concentrations from the North West Atlantic, to identify seasonal successional trends amongst phytoplankton populations. Changes in phytoplankton community were also analysed as a function of mean equivalent spherical diameter (MESD) derived from absorption measurements, photosynthetic rates, water-column stratification and temperature. Well-mixed conditions in spring to early summer were associated with populations of large cells containing high concentrations of fucoxanthin, chlorophyll-c1 and chlorophyll-c2 relative to chlorophyll-a (Chl a). As stratification increased over the course of the summer, these cells were replaced by populations dominated by chlorophyll-b, 19'-hexanoyloxyfucoxanthin, 19'-butanoyloxyfucoxanthin and divinyl chlorophyll-a, indicative of small picophytoplankton. As stratification decreased in autumn, MESD and alloxanthin increased, suggesting the presence of cryptophytes. Positive relationships were found between MESD and the quantum yield of photosynthesis (φm) for 7 out of the 8 phytoplankton clusters identified, while negative relationships between mean mixed layer photosynthetically active radiation and φm and the light limited slope of photosynthesis (αB) were observed for 4 clusters, as a result of nutrient limitation and photo-protection. The highest photosynthetic rates were associated with a pico & nanophytoplankton communities, which increased from spring to late summer as stratification intensified. By contrast, diatom communities had the lowest photosynthetic rates throughout the year. These successional patterns in the dominant phytoplankton size-class and phenology support Margalef's mandala in terms of the relationship between turbulence and community structure. The study sheds new light on assemblages dominated by smaller cells, under warm, stratified conditions, having higher photosynthetic efficiencies, which has implications for the carbon flux in the NW Atlantic.

Changes across 66°W, the Caribbean Sea and the Western boundaries of the North Atlantic Subtropical Gyre

A World Ocean Circulation Experiment Hydrographic Program along with a Global Repeat Hydrography Program occupied sections along 66°W in the North West Atlantic Ocean in 2003 and 2012. Hydrographic variables, tracers and LADCP measurements were collected in situ. This section together with the North American and South American Coasts create a closed volume, excluding any flow through the Panama Canal. Combining mass, silica and LADCP information with constraints in an inverse box model we obtain a strong eastward flow of the Gulf Stream (100.1 ± 4.6 Sv in 2003 and 123.8 ± 4.4 Sv in 2012), and westward flows of the Caribbean Current (−24.4 ± 1.0 Sv in 2003 and −24.2 ± 1.1 Sv in 2012) and Deep Western Boundary Current (DWBC). The DWBC carries the ventilated waters of the Labrador Sea and the Nordic Seas. Comparing the results of 2003 and 2012, an insignificant reduction is observed in the DWBC transport (−17.3 ± 2.9 Sv and −15.0 ± 2.5 Sv for 2003 and 2012, respectively). The net heat fluxes do not show major changes through the section during both cruises (−0.23 ± 0.08 PW in 2003 and −0.21 ± 0.12 PW in 2012). In contrast, freshwater fluxes present positive values in the dry season (0.24 Sv in spring 2012) and negative values in the wet season (−0.32 Sv in fall 2003). The difference between both cruises may be due to seasonal variability in the area.

Mitochondrial DNA haplotype diversity and origin of captive sand tiger sharks (Carcharias taurus)

The sand tiger shark (Carcharias taurus) is listed as globally vulnerable with geographically confined and disrupted global populations with little or no gene flow between them. Captive breeding in aquaria of these sharks would reduce the need to populate displays with wild-caught individuals, however, sand tigers are notoriously difficult to breed in captivity. In this study we analysed 520bp of the mitochondrial D-loop to assess the haplotype diversity of 19 captive sand tiger sharks, from UK and US aquaria sampled in a non-invasive fashion through DNA extracted from shed teeth. Data obtained were compared to known geographically mapped wild haplotypes to establish whether individuals from different global populations are being housed together. We were able to identify the haplotype of a minimum of ten of the 19 sharks, detecting four different haplotypes, with a previously undescribed haplotype (Haplotype K) found from a captive sample. A major genetic subdivision between the haplotypes of the North West Atlantic and the other global populations has been previously shown from population genetic analyses. Our results indicate that captive sharks can be from either side of this subdivision and occasionally these can be co-housed in the same aquarium. Since sharks with highly divergent genetic ancestry are being kept together, these findings have implications for conservation efforts regarding the individual needs of sand tiger shark populations and for captive breeding program success rates.

Translating China to the Atlantic West: Self, other, and Lin Yutang’s resistance

ABSTRACTThis article examines how the Chinese author and translator Lin Yutang challenged the misconstructions of China in the Atlantic West. From the perspective of the inhabitants of the Pacific Rim, the Atlantic is considered a symbol and metaphor for the union of the West (Europe and North America). Due to significant cultural and linguistic differences, China has frequently been misrepresented by Atlantic nations. Within this context, the leading translation theorist Lin Yutang conceived two key translation concepts, tongshun (通顺, fluency) and zhongshi (忠实, fidelity, faithfulness), as powerful weapons to fight against this trend of false recognition. This article analyzes Lin’s means of representing China by looking at (para)textual materials he produced. It explores how Lin combines tongshun and zhongshi to forge a space of zhongyong (中庸, central harmony), a space that reveals the unceasing efforts in mediating, through the translator’s balancing act, between his “Chinese Self” and “Atlantic-Western Other.” The space of zhongyong can be read as Lin’s creation that goes beyond the confines of strict “surrendering” and “withstanding.” Lin’s translation of China to the Atlantic nations therefore presents the possibility of transcending the limits of traditional representations, and offers a renewed understanding of the relationship between China and the Atlantic West.

Fauna of tintinnids (Tintinnida, Ciliata) during an Arctic-Antarctic cruise,with the S/V "Croatian Tern".

An investigation of large tintinnids was carried out during the Arctic-Antarctic cruise aboard the S/V "Croatian Tern" in the period from 1994 to 1997. Samples were collected at 33 stations by vertical tows with a Nansen net with a 53 µm mesh size in the Mediterranean Sea, North Atlantic, Labrador Sea, Baffin Bay, the Beaufort, Chukchi and Bering Seas, East North Pacific, South Pacific, South East Pacific, Scotia Sea, and South West Atlantic. A total of 47 species of tintinnids were found, with the greatest diversity in the Tropical areas of the Pacific, Arctic and Subarctic. A very high total abundance was registered in the Bering Sea of 247,393 ind.m-3 and in the South-eastern Pacific of 66,211 ind.m-3. The dominant species in the northern areas was Ptychocylis obtusa and in the southern areas Eutintinnus rugosus.

Ichthyofauna of the inner shelf of Paraná, Brazil: checklist, geographic distribution, economic importance and conservation status

Abstract Comprehensive species checklists are essential to effectively implementing preservation and recovery measures, and should assess conservation status, vulnerability degree and anthropogenic threats. This checklist was compiled from fish species recorded in surveys conducted over the last 30 years in the shallow inner continental shelf in the State of Paraná, Brazil. Information on biogeography, conservation status, economic importance and degree of species’ vulnerability are provided. A total of 272 fish species were recorded, spanning 25 orders and 88 families. The most speciose family was Sciaenidae (25 species), followed by Carangidae (23), Engraulidae (10), Carcharhinidae (9), Epinephelidae (9) and Paralichthyidae (9). Most species occurring in Paraná’s shallow inner continental shelf are restricted to the West Atlantic. In terms of economic importance, 93% (253) of the species recorded were of fishery, aquaculture or aquaria interest. A notable fraction (39%) of the recorded species was classified as having moderate to very high vulnerability to extinction. In particular, 28 species (10%) were listed as globally endangered, and 34 species (12%) were listed as endangered in the Brazilian territory.

Kilometric Scale Modeling of the North West European Shelf Seas: Exploring the Spatial and Temporal Variability of Internal Tides

AbstractThe North West European Shelf break acts as a barrier to the transport and exchange between the open ocean and the shelf seas. The strong spatial variability of these exchange processes is hard to fully explore using observations, and simulations generally are too coarse to simulate the fine‐scale processes over the whole region. In this context, under the FASTNEt program, a new NEMO configuration of the North West European Shelf and Atlantic Margin at 1/60° (∼1.8 km) has been developed, with the objective to better understand and quantify the seasonal and interannual variability of shelf break processes. The capability of this configuration to reproduce the seasonal cycle in SST, the barotropic tide, and fine‐resolution temperature profiles is assessed against a basin‐scale (1/12°, ∼9 km) configuration and a standard regional configuration (7 km resolution). The seasonal cycle is well reproduced in all configurations though the fine‐resolution allows the simulation of smaller scale processes. Time series of temperature at various locations on the shelf show the presence of internal waves with a strong spatiotemporal variability. Spectral analysis of the internal waves reveals peaks at the diurnal, semidiurnal, inertial, and quarter‐diurnal bands, which are only realistically reproduced in the new configuration. Tidally induced pycnocline variability is diagnosed in the model and shown to vary with the spring neap cycle with mean displacement amplitudes in excess of 2 m for 30% of the stratified domain. With sufficiently fine resolution, internal tides are shown to be generated at numerous bathymetric features resulting in a complex pycnocline displacement superposition pattern.

Rapid Water Transport by Long‐Lasting Modon Eddy Pairs in the Southern Midlatitude Oceans

AbstractWater in the ocean is generally carried with the mean flow, mixed by eddies, or transported westward by coherent eddies at speeds close to the long baroclinic Rossby wave speed. Modons (dipole eddy pairs) are a theoretically predicted exception to this behavior, which can carry water to the east or west at speeds much larger than the Rossby wave speed, leading to unusual transports of heat, nutrients, and carbon. We provide the first observational evidence of such rapidly moving modons propagating over large distances. These modons are found in the midlatitude oceans around Australia, with one also seen in the South Atlantic west of the Agulhas region. They can travel at more than 10 times the Rossby wave speed of 1–2 cm s−1 and typically persist for about 6 months carrying their unusual water mass properties with them, before splitting into individual vortices, which can persist for many months longer.