Central South Pacific Ocean Research Articles

Abundance, production, and migrations of nesting green turtles at Rose Atoll, American Samoa, a regionally important rookery in the Central South Pacific Ocean

Sea turtles are a taxon of conservation concern and are highly migratory, exposing them to a variety of threats (e.g., fisheries bycatch, direct harvest) across their lifetime. Understanding the abundance of nesting females, hatchling production, and migratory movements - three of the most basic biological data needs for this species group - is imperative for population assessment. This study summarizes novel data most relevant to population assessments of the endangered central south Pacific (CSP) green turtle (Chelonia mydas) population, determined from annual rapid assessment surveys (mean survey duration=7.6 days year-1, n=61 survey days over 8 nesting seasons) and satellite telemetry at Rose Atoll, American Samoa, from 2012 to 2019. A minimum of 138 unique females nested in the Rose Atoll National Wildlife Refuge (RANWR) over the study period with 218 total females observed. Satellite tracks of post-nesting females suggest Fiji (n=33/48, 70.2%) is the primary foraging ground for turtles nesting at RANWR, though other areas throughout the south Pacific Ocean are also important. Limited data suggest hatchling production was high (average hatching success=92.3%) and nest temperature data collected from 2017-2019 suggest primary sex ratios were likely balanced during this time. These are positive signs for the resilience of this nesting population, but climate change poses threats to RANWR and other low-lying tropical islands throughout the central south Pacific, as nesting areas are potentially exposed to beach erosion, tidal inundations, and increasing temperatures leading to sex bias and embryonic death.

Insights into the origin of precipitation moisture for tropical cyclones during rapid intensification process

In this study, we identified the moisture sources for the precipitation associated with tropical cyclones (TCs) during the rapid intensification (RI) process from 1980 to 2018 by applying a Lagrangian moisture source diagnostic method. We detected sixteen regions on a global scale for RI events distributed as follows: four in the North Atlantic (NATL), two in the Central and East Pacific Ocean (NEPAC), the North Indian Ocean (NIO) and South Indian Ocean (SIO), and three in the South Pacific Ocean (SPO) and the Western North Pacific Ocean (WNP). The moisture uptake (MU) mostly was from the regions where TCs underwent RI. The Western NATL, tropical NATL, Caribbean Sea, the Gulf of Mexico and the Central America and Mexico landmass supported ∼85.4% of the precipitating moisture in the NATL, while the latter source and the eastern North Pacific Ocean provided the higher amount of moisture in NEPAC (∼84.3%). The Arabian Sea, the Bay of Bengal and the Indian Peninsula were the major moisture sources in NIO, contributing approximately 81.3%. The eastern and western parts of the Indian Ocean supplied most of the atmospheric humidity in SIO (∼83.8%). The combined contributions (∼87.9%) from the western and central SPO and the Coral Sea were notably higher in SPO. Meanwhile, TCs in the WNP basin mostly received moisture from the western North Pacific Ocean, the Philippine Sea and the China Sea, accounting for 80.1%. The remaining moisture support in each basin came from the summed contributions of the remote sources. Overall, RI TCs gained more moisture up to 2500 km from the cyclone centre than those slow intensification (SI) and the total MU was approximately three times higher during RI than SI. Finally, the patterns of the MU differences respond to the typical pathways of moisture transport in each basin.

Taxonomy and systematics of shallow-water tropical benthic foraminifera from the lagoon environments at Bora Bora, Society Islands, French Polynesia

Bora Bora is a volcanic island in the tropical central South Pacific Ocean with a barrier reef and large well developed back-reef lagoons. It forms part of the system of shallow water environments in the archipelagos of French Polynesia that provide stepping stones for the interconnectivity of shallow marine faunas between the tropical Western and Eastern Pacific biogeographic regions. The fauna has many similarities to foraminiferal faunas in the south western Indo-Pacific but has been demonstrated to be unique. This study provides illustrations and discussions of most of the 184 species of benthic foraminifera identified from sediments in the back-reef lagoon environments at Bora Bora, that span from the shallow immediate back-reef sand banks, to the deep lagoons and to the coastal fringing reefs and embayments around the volcanic island. The illustrated specimens and taxonomic discussions are aimed at providing an identification guide to shallow water tropical benthic foraminifera from the central South Pacific region. Six new species have been established, including Textularia boraboraensis, Miliolinella mccullochae, Quinqueloculina guilcheri, Triloculina karimimossadeghae, Coscinospira georgforsteri, and Elphidium venecpeyreae. This study also proposes that the family of cymbaloporetids, Cymbaloporidae, are placed within the Superfamily Discorboidea.

Corrosion Behavior of Copper Exposed in Marine Tropical Atmosphere in Rapa Nui (Easter Island) Chile 20 Years after MICAT

Atmospheric corrosion of copper, exposed on a tropical island in the South-Central Pacific Ocean, was reported and compared with those of a very similar study at the same site conducted 20 years earlier. The new measurements—taken over three years of exposure, from 2010 to 2013—quantified corrosion by mass loss, characterized corrosion products by X-ray diffraction (DRX) and Raman techniques, observed the attack morphology by Scanning Electron Microscope (SEM), and evaluated the patina resistance using electrochemical techniques. The results showed a copper corrosivity category of C4, and the main copper patina compound, cuprite, was porous, nonhomogeneous, and thin. Electrochemical measurements showed cuprite layer growth as a function of the exposure time, and the morphology did not favor corrosion protection. Finally, when comparing the results to those of a study 22 years previous, the copper corrosion rates increased only slightly, even with increased contaminants associated with growing local populations and continuous tourism on the island.

Untangling local and remote influences in two major petrel habitats in the oligotrophic Southern Ocean.

Ocean circulation connects geographically distinct ecosystems across a wide range of spatial and temporal scales via exchanges of physical and biogeochemical properties. Remote oceanographic processes can be especially important for ecosystems in the Southern Ocean, where the Antarctic Circumpolar Current transports properties across ocean basins through both advection and mixing. Recent tracking studies have indicated the existence of two large-scale, open ocean habitats in the Southern Ocean used by grey petrels (Procellaria cinerea) from two populations (i.e., Kerguelen and Antipodes islands) during their nonbreeding season for extended periods during austral summer (i.e., October to February). In this work, we use a novel combination of large-scale oceanographic observations, surface drifter data, satellite-derived primary productivity, numerical adjoint sensitivity experiments, and output from a biogeochemical state estimate to examine local and remote influences on these grey petrel habitats. Our aim is to understand the oceanographic features that control these isolated foraging areas and to evaluate their ecological value as oligotrophic open ocean habitats. We estimate the minimum local primary productivity required to support these populations to be much <1% of the estimated local primary productivity. The region in the southeast Indian Ocean used by the birds from Kerguelen is connected by circulation to the productive Kerguelen shelf. In contrast, the region in the south-central Pacific Ocean used by seabirds from the Antipodes is relatively isolated suggesting it is more influenced by local factors or the cumulative effects of many seasonal cycles. This work exemplifies the potential use of predator distributions and oceanographic data to highlight areas of the open ocean that may be more dynamic and productive than previously thought. Our results highlight the need to consider advective connections between ecosystems in the Southern Ocean and to re-evaluate the ecological relevance of oligotrophic Southern Ocean regions from a conservation perspective.

Morphology of larvae of 6 Lampanyctus species in the central South Pacific Ocean with notes on their occurrence

Morphology of larvae of 6 Lampanyctus species in the central South Pacific Ocean with notes on their occurrence

Characterization of south central Pacific Ocean wind regimes in present and future climate for pearl farming application

In the South Pacific (SP) pearl farming atolls, wind is the main driver of lagoon water circulation, affecting dispersal and survival of pearl oyster larvae. To characterize typical wind conditions in the SP, wind regime classifications are performed from regional climate simulations using the WRF model, for present-day and for the end of the 21st century under RCP8.5 scenario conditions. At the daily time-scale, 4 regimes are identified: a trade-wind, a north-easterly, and two easterly regimes. Their characteristics are driven by large-scale circulation and climate modes of variability. In future projection, all regimes are characterized by a ~15% wind speed increase, while directions and occurrence frequencies undergo marginal changes. At the monthly time-scale that corresponds to pearl oyster pelagic larval duration, nine wind regimes are determined including three regimes with wind reversals. These regimes can be used to model typical lagoon conditions during larval dispersal.

A Plan for a Long-Term, Automated, Broadband Seismic Monitoring Network on the Global Seafloor

AbstractEstablishing an extensive and highly durable, long-term, seafloor network of autonomous broadband seismic stations to complement the land-based Global Seismographic Network has been a goal of seismologists for decades. Seismic signals, chiefly the vibrations from earthquakes but also signals generated by storms and other environmental processes, have been processed from land-based seismic stations to build intriguing but incomplete images of the Earth’s interior. Seismologists have mapped structures such as tectonic plates and other crustal remnants sinking deep into the mantle to obtain information on their chemical composition and physical state; but resolution of these structures from land stations is not globally uniform. Because the global surface is two-thirds ocean, increasing the number of seismic stations located in the oceans is critical for better resolution of the Earth’s interior and tectonic structures. A recommendation for a long-term seafloor seismic station pilot experiment is presented here. The overarching instrumentation goal of a pilot experiment is performance that will lead to the installation of a large number of long-term autonomous ocean-bottom seismic stations. The payoff of a network of stations separated from one another by a few hundred kilometers under the global oceans would be greatly refined resolution of the Earth’s interior at all depths. A second prime result would be enriched understanding of large-earthquake rupture processes in both oceanic and continental plates. The experiment would take advantage of newly available technologies such as robotic wave gliders that put an affordable autonomous prototype within reach. These technologies would allow data to be relayed to satellites from seismometers that are deployed on the seafloor with long-lasting, rechargeable batteries. Two regions are presented as promising arenas for such a prototype seafloor seismic station. One site is the central North Atlantic Ocean, and the other high-interest locale is the central South Pacific Ocean.

Role of Iron in the Marquesas Island Mass Effect

AbstractA remarkable chlorophyll‐a concentration (Chl, a proxy of phytoplankton biomass) plume can be noticed on remotely sensed ocean color observations at the boundary separating the equatorial mesotrophic from the subtropical oligotrophic waters in the central South Pacific Ocean. This prominent biological feature is known as the island mass effect of the Marquesas archipelago. Waters surrounding these islands present high macronutrient concentrations but an iron depletion. In this study, the origin of Chl enhancement is investigated using a modeling approach. Four simulations based on identical physical and biogeochemical forcings but with different iron sources are conducted and analyzed. Only simulations considering an iron input from the island sediments present similar patterns (despite being too weak) of vertical and horizontal Chl distributions as compared to biogeochemical‐Argo profiling float and satellite observations. In addition, simulations with no other iron input than the boundary forcings reveal the relative importance of remote processes in modulating the seasonal pattern of Chl around the archipelago through horizontal advection of nutrient‐rich waters from the equator toward the archipelago and vertical mixing uplifting deep nutrient‐rich waters toward the upper lit layer.

Impact of multiyear La Niña events on the South and East Asian summer monsoon rainfall in observations and CMIP5 models

Impact of multi-year La Nina events on South and East Asian summer monsoon rainfall are examined in the observations and Coupled Model Intercomparison Project Phase 5 (CMIP5) models. The analysis is carried out for the successive two summers, referred to as the first and second years during the period of 1948–2016. Composite analysis suggests that La Nina related sea surface temperature cooling is slightly high in the central and eastern equatorial Pacific during the first year summer. This anomalous cooling associated with La Nina is slightly shifted towards south and south-central Pacific Ocean during the second year. An Atlantic Nino like pattern is evident in the first year unlike the second year. Negative rainfall anomalies are apparent over most of the south Asian region except Bangladesh and Sundarbans, during the first year. Moisture convergence corroborated by low-level circulation to the north of Bangladesh and central India supports the positive rainfall anomalies in the first year. A weak circulation and negative vertically integrated moisture (VIM) anomalies in the rest of the subcontinent are consistent with the negative rainfall anomalies. In addition to these changes, the Atlantic Nino has also been found to be influencing the South Asian rainfall, remotely, during the first year. In the case of the second year, positive rainfall anomalies over the south Asian monsoon region is noted. An anomalous low-level cyclonic circulation over the central Bay of Bengal enhanced the moisture transport into the Indian subcontinent, causing positive rainfall anomalies. Moreover, an anomalous upper level divergence extends from the southeast Indian Ocean, towards the Indian subcontinent, due to La Nina’s response in the second year, which is found to be weak in the first year. This clearly suggests that the enhanced rainfall over the South Asian region is influenced remotely by La Nina forcing as well as local circulation changes during both the years. The East Asian monsoon region reported a tri-pole like structure in the rainfall anomalies, with positive values over southern and central China and negative over parts of Myanmar, Thailand and Cambodia regions and north-east China—North Korea during the first year and vice-versa in the second year. A positive–negative–positive structure in the VIM anomalies is seen in the East Asian region and it supports similar rainfall anomalies during the second year. We have further examined the ability of CMIP5 models in representing multiyear La Nina teleconnections to the south and East Asian summer monsoons. Some models are able to reproduce the South Asian rainfall and circulation anomalies well in the second year, but failed to do so, in the first. The factors responsible for weak teleconnections in the models are discussed in detail.

Provenance of nutrients in submarine fresh groundwater discharge on Tahiti and Moorea, French Polynesia

Submarine fresh groundwater discharge (SFGD) provides a pathway for dissolved nutrients and other solutes from land to the ocean. It connects pollution from anthropogenic land use with coastal marine waters. In case of the oligotrophic central South Pacific Ocean around Tahiti and Moorea, French Polynesia, nutrient concentrations are particularly low. Both islands are surrounded by tropical coral reefs, which are highly sensitive to nutrient concentrations in the ambient water so that a surplus of nutrients, e.g. from SFGD, could lead to the degradation of coral reef ecosystems.We examined nutrient contributions from different land cover classes to nutrient fluxes through SFGD by combining nutrient concentration data, spatial data, oxygen and hydrogen isotope ratios of water (δ18OH2O and δ2HH2O, respectively) and nitrogen and oxygen isotope ratios of nitrate (δ15NNO3- and δ18ONO3-). Undeveloped land provides measurable quantities of phosphate while nitrate concentrations are often below the detection limit. The bulk of the nutrient load in nutrient enriched groundwater is of anthropogenic origin. It enters the aquifer system at low altitudes, where catchments are characterized by anthropogenic land use. Elevated nitrate concentrations are mainly associated with septic waste/manure inputs in fresh water.This study elucidates sources of nutrients in the groundwater of two volcanic islands, highlighting the impact that even a small populated area along the coast of an island can have, as well as the differences in nutrient transport between these seemingly similar locations.

Intermediate water flows in the western South Pacific: as revealed by individual Argo floats trajectories and a model re-analysis

Abstract. Thanks to the autonomous Argo floats of the OUTPACE cruise (Oligotrophy to UlTra-oligotrophy PACific Experiment) and of the THOT (TaHitian Ocean Time series) project, some features of intermediate-flow dynamics, at around 1000 m depth, within the central and western South Pacific Ocean (around 19∘ S, 156∘ E–150∘ W) are described. In the Coral Sea, we highlight minima in dissolved oxygen of 140 µmol kg−1 that are associated with the signature of a southward transport of waters between two zonal jets: from the North Vanuatu Jet to the North Caledonia Jet. This transport takes place in the core of a cyclonic eddy or via the path between a cyclonic eddy and an anticyclonic one, highlighting the importance of mesoscale dynamics in upper thermocline and surface layers. Further east, we observe a strong meridional velocity shear with long-term float trajectories going either eastward or westward in the lower thermocline. More interestingly, these trajectories also exhibit some oscillatory features. Those trajectories can be explained by a single Rossby wave of 160-day duration and 855 km wavelength. Considering the thermohaline context, we confirm the meridional shear of zonal velocity and highlight a permanent density front that corresponds to the interface between Antarctic intermediate waters and North Pacific deep waters. Hence both circulation and thermohaline contexts are highly prone to instabilities and wave propagation.

Age and growth estimates of the blue shark Prionace glauca in the central South Pacific Ocean

The age and growth of the blue shark Prionace glauca in the central South Pacific is described based on 267 specimens that were collected by scientific observers on board Taiwanese large-scale tuna longline fleets between May 2009 and May 2011. Growth band pairs (identified as translucent and opaque bands) were counted on images photographed from X-ray films of the vertebrae from the caudal peduncle region. The marginal increment ratio and centrum edge analysis indicated that a growth band pair was formed on the vertebral centrum once per year. The band pairs after the birthmark were counted from 2 to 11 for females and from 2 to 15 for males. The bias corrected Akaike information criterion indicated that the von Bertalanffy growth function (VBGF) best fitted the observed total length (TL)-at-age data. The parameters of sex-specific VBGF were estimated as follows: for females, theoretical maximum length (L∞) mean±s.d.=330.4±46.6cm TL, growth coefficient k=0.164±0.057year–1 and theoretical age at length 0 (t0)=–1.29±0.78 years; for males, L∞=376.6±32.6cm TL, k=0.128±0.022year–1 and t0=–1.48±0.54 years. The longevities were estimated to be at least 16.8 and 21.6 years for females and males respectively.

Evaluating the phylogenetic position of the goby genus Kelloggella (Teleostei: Gobiidae), with notes on osteology of the genus and description of a new species from Niue in the South Central Pacific Ocean

Evaluating the phylogenetic position of the goby genus Kelloggella (Teleostei: Gobiidae), with notes on osteology of the genus and description of a new species from Niue in the South Central Pacific Ocean

Are Sea Surface Temperature satellite measurements reliable proxies of lagoon temperature in the South Pacific?

In remote coral reef environments, lagoon and reef in situ measurements of temperature are scarce. Sea Surface Temperature (SST) measured by satellite has been frequently used as a proxy of the lagoon temperature experienced by coral reef organisms (TL) especially during coral bleaching events. However, the link between SST and TL is poorly characterized. First, we compared the correlation between various SST series and TL from 2012 to 2016 in three atolls and one island in the Central South Pacific Ocean. Simple linear correlation between SST and TL ranged between 0.44 and 0.97 depending on lagoons, localities of sensors, and type of SST data. High-resolution-satellite-measurements of SST inside the lagoons did not outperform oceanic SST series, suggesting that SST products are not adapted for small lagoons. Second, we modelled the difference between oceanic SST and TL as a function of the drivers of lagoon water renewal and mixing, namely waves, tide, wind, and season. The multivariate models reduced significantly the bias between oceanic SST and TL. In atoll lagoons, and probably in other hydrodynamically semi-open systems, a correction taking into account these factors is necessary when SST are used to characterize organisms’ thermal stress thresholds.

Basin-scale distribution of prokaryotic phylotypes in the epipelagic layer of the Central South Pacific Ocean during austral summer

In the present study, we used catalyzed reporter deposition-fluorescence in situ hybridization to quantify the abundance of five bacterial (Alphaproteobacteria, SAR11, Gammaproteobacteria, SAR86, and Bacteroidetes) and two archaeal (Crenarchaeota and Euryarchaeota) phylotypes in the epipelagic layer (0–200 m) of the Central South Pacific Ocean along 170°W from 0° to 40°S. We found that the distribution patterns of these phylotypes differed from each other. All phylotypes except Gammaproteobacteria were particularly abundant at the surface water of the equatorial region, whereas Gammaproteobacteria was relatively abundant in the area from the southern part of the South Pacific Ocean. SAR11, affiliated with Alphaproteobacteria was the dominant phylotype at all depths, throughout the study area. The abundance of SAR11 significantly increased with chlorophyll a concentration, suggesting that phytoplankton could affect their distribution pattern. There was a positive correlation between Bacteroidetes abundance and water temperature, suggesting that the temperature gradient could be a critical factor determining their distribution in the South Pacific Ocean. Crenarchaeota and Euryarchaeota were more abundant at the equatorial region than in other study areas. Euryarchaeota abundance significantly decreased with depth, and increased with chlorophyll a concentration. This suggests that there was ecological interaction between Euryarchaeota and phytoplankton in the equatorial surface. Our data indicate that distinct hydrographic properties such as seawater temperature, salinity, and the concentrations of chlorophyll a and nutrients can principally control the basin-scale distribution of different prokaryotic phylotypes in the epipelagic layer of the Central South Pacific Ocean.

Litter and seabirds found across a longitudinal gradient in the South Pacific Ocean

Abundances and composition of marine litter and seabirds were estimated in the central South Pacific (SP) Ocean between the Chilean continental coast and the Easter Island Ecoregion. Litter was dominated by plastics throughout the study area, but the proportion of plastics was higher at sea and on the oceanic islands than in coastal waters and on continental beaches. Litter densities were higher close to the center of the SP subtropical gyre compared to the continental coast. The seabird assemblage was diverse (28 species), and several endemic species were recorded. Seabird abundances were higher in the coastal waters and around Juan Fernández Islands off the continental coast than in the Oceanic and Polynesian sectors. Endangered species breeding on Salas & Gómez Island were observed in the Polynesian sector, which suggests a high potential for negative interactions between seabirds and floating litter, both occurring in high densities in this sector.

Population structure of humpback whales in the western and central South Pacific Ocean as determined by vocal exchange among populations

For cetaceans, population structure is traditionally determined by molecular genetics or photographically identified individuals. Acoustic data, however, has provided information on movement and population structure with less effort and cost than traditional methods in an array of taxa. Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or song, that is similar among all males in a population. The rapid cultural transmission (the transfer of information or behavior between conspecifics through social learning) of different versions of this display between distinct but interconnected populations in the western and central South Pacific region presents a unique way to investigate population structure based on the movement dynamics of a song (acoustic) display. Using 11 years of data, we investigated an acoustically based population structure for the region by comparing stereotyped song sequences among populations and years. We used the Levenshtein distance technique to group previously defined populations into (vocally based) clusters based on the overall similarity of their song display in space and time. We identified the following distinct vocal clusters: western cluster, 1 population off eastern Australia; central cluster, populations around New Caledonia, Tonga, and American Samoa; and eastern region, either a single cluster or 2 clusters, one around the Cook Islands and the other off French Polynesia. These results are consistent with the hypothesis that each breeding aggregation represents a distinct population (each occupied a single, terminal node) in a metapopulation, similar to the current understanding of population structure based on genetic and photo-identification studies. However, the central vocal cluster had higher levels of song-sharing among populations than the other clusters, indicating that levels of vocal connectivity varied within the region. Our results demonstrate the utility and value of using culturally transmitted vocal patterns as a way of defining connectivity to infer population structure. We suggest vocal patterns be incorporated by the International Whaling Commission in conjunction with traditional methods in the assessment of structure.

Significance of new records of Tridacna squamosa Lamarck, 1819, in the Tuamotu and Gambier Archipelagos (French Polynesia)

The giant clam subfamily Tridacninae (family Cardiidae) is an important group of bivalve molluscs found throughout the Red Sea and Indo-Pacific, from East Africa to the Eastern Pacific biogeographic region. The Tridacna genus is currently revised with numerous cryptic species identified with molecular markers. New Tridacna records from the fringe of the known distribution areas are extremely useful to identify genetically unique species, geographic ranges, and to examine processes associated with species differentiation. While Tridacna maxima is abundant in French Polynesia (Central South Pacific Ocean) the larger fluted giant clam Tridacna squamosa was formerly reported only in the Austral Islands in the south. Following a recent survey that spanned 23 islands and atolls of the Society, Tuamotu and Gambier Archipelagos, the presence of T. squamosa between the Cook Islands and Pitcairn Islands is confirmed using both morphological and molecular information, suggesting a relic distribution across the Central Pacific Ocean. Tridacna squamosa is rare, but present throughout Tuamotu and Gambier. However, it remained undetected from the Society Islands, probably due to historical over-fishing. This species is valued by local inhabitants, and is sought after mainly as gifts and also for a limited local shell trade. The rarity of T. squamosa may call for conservation measures in the near future.

Population structure of humpback whales in the western and central South Pacific Ocean determined by vocal cultural exchange

Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or “song,” which is shared by all males within a population. The rapid cultural transmission of this display between distinct but interconnected populations within the western and central South Pacific region presents a unique opportunity to investigate population connectivity based on a vocal display. Quantitative analyses were conducted on eleven years of data to investigate vocal groupings based on song types shared between populations, to produce an acoustically derived population structure for the region. Four distinct vocal groupings resulted; the western group contained a single population, off eastern Australia, the central group was comprised of whales around New Caledonia, Tonga and American Samoa, and finally the whales of the eastern region were split into two groups, one around the Cook Islands and the other in the waters of French Polynesia. These groupings broadly agree with results obtained using genetic and photo-identification methods, and confirm that humpback whales are likely to form separate breeding populations rather than panmictic subpopulations. This study demonstrates the utility of using culturally transmitted vocal patterns as a way of defining populations, at least in this species.