Aggregation Sites Research Articles

Promotion of freelance services in the digital environment

The article analyses the concept of freelance (temporary, project employment) within the framework of new approaches to employment and changes in the perception of remote and hybrid forms of employment by society and business after the COVID-19 pandemic. The following segments of the labour market where freelancing is the most common element are considered: copywriting, law, software development, design of buildings and structures, creation of graphic, audio and video content, consulting, provision of expertise, tutoring. The portrait of a freelancer is studied in detail according to such characteristics as the region of residence, sex, average age, the share of “real” freelancers and the share of part-timers, experience of interaction with freelance platforms, tax status, single and team players, the reasons for choosing freelancing as a form of employment, the most valuable component of freelancing, the disadvantages of freelancing as a form of employment and motivation of freelancers. The main methods of promoting freelance services in the digital environment are identified: a portfolio site, active maintenance of a professional profile in social networks and its advertising, registration on aggregator sites, freelance and human-cloud platforms. The main element of the portfolio site is highlighted – the works performed by a freelancer (texts, photographs, graphics and similar materials) – along with the key factors that a freelancer needs to consider when creating and maintaining a portfolio site and the most common mistakes

The influence of micro-scale thermal habitat on the movements of juvenile white sharks in their Southern California aggregation sites

While juvenile white sharks (JWS) can display regional endothermy, the need to maintain internal temperatures within an energetically favorable range likely drives thermoregulatory movements to maximize growth and foraging efficiency. Many JWS from the northeastern Pacific population aggregate seasonally in nearshore nursery habitats throughout the Southern California Bight and historic data show that inter-seasonal movement patterns may be heavily dependent on ambient water temperature. However, the degree to which micro-scale (e.g., ~10 m2) water temperature heterogeneity influences JWS three-dimensional movement within nearshore aggregation sites is unknown. High-resolution temperature and passive acoustic-telemetry geo-positional data were used to quantify how temperature and vertical thermal stratification influenced JWS movement using several modeling approaches. JWS selected for water temperatures between 16 – 22°C and depths shallower than 2 m. Sharks occupied deeper waters during dawn and dusk periods, and their distance from the seafloor and spatial orientation of their depth distribution was significantly related to the thermal structure of the water column across the monitored area. Tagged sharks remained above a 16°C thermal threshold and altered their horizontal and vertical distributions accordingly. While high-resolution movement and environmental data provide improved predictability of micro-scale habitat use and distribution, other variables such as prey distribution, behavior, and competition would further improve habitat use models for this highly mobile species.

Whale shark abundance, spatial distribution and effective tourism areas in the northern Mexican Caribbean

ABSTRACT Every year, from June to September, the whale shark (Rhincodon typus) is present in the Mexican Caribbean and has become a highly attractive tourist resource. In this study, we assess the spatial and temporal distribution of whale sharks and estimate the size of the effective tourism area from data collected between 2016 and 2021. The main whale shark aggregation site in the Mexican Caribbean is called ‘El Azul’, it has an average size of 400 km2. Using aerial survey data, we found 37 whale shark aggregations where we counted 1–170 individuals and 16–150 tourist boats. The average size of the area covered by these groups was 2.9 km2. The highest density of whale sharks was recorded in 2020 (48 whale sharks per km2) and the lowest in 2021 (5 whale sharks per km2). Estimating the effective tourism area (where whale shark tourism takes place) within the entire aggregation area is important to refine tourism carrying capacity calculations and to avoid miscalculations that could lead to over-exploitation of whale shark tourism activities with negative consequences for the species. The information from this study is directly applicable to adaptive ecotourism management, improving the sustainability of whale shark tourism, and biological monitoring.

Deposition of silica in sorghum root endodermis modifies the chemistry of associated lignin.

Silica aggregates at the endodermis of sorghum roots. Aggregation follows a spotted pattern of locally deposited lignin at the inner tangential cell walls. Autofluorescence microscopy suggests that non-silicified (-Si) lignin spots are composed of two distinct concentric regions of varied composition. To highlight variations in lignin chemistry, we used Raman microspectroscopy to map the endodermal cell wall and silica aggregation sites in sorghum roots grown hydroponically with or without Si amendment. In +Si samples, the aggregate center was characterized by typical lignin monomer bands surrounded by lignin with a low level of polymerization. Farther from the spot, polysaccharide concentration increased and soluble silicic acid was detected in addition to silica bands. In -Si samples, the main band at the spot center was assigned to lignin radicals and highly polymerized lignin. Both +Si and -Si loci were enriched by aromatic carbonyls. We propose that at silica aggregation sites, carbonyl rich lignin monomers are locally exported to the apoplast. These monomers are radicalized and polymerized into short lignin polymers. In the presence of silicic acid, bonds typically involved in lignin extension, bind to silanols and nucleate silica aggregates near the monomer extrusion loci. This process inhibits further polymerization of lignin. In -Si samples, the monomers diffuse farther in the wall and crosslink with cell wall polymers, forming a ring of dense lignified cell wall around their export sites.

Elimination of virus-like particles reduces protein aggregation and extends replicative lifespan in Saccharomyces cerevisiae

A major consequence of aging and stress, in yeast to humans, is an increased accumulation of protein aggregates at distinct sites within the cells. Using genetic screens, immunoelectron microscopy, and three-dimensional modeling in our efforts to elucidate the importance of aggregate annexation, we found that most aggregates in yeast accumulate near the surface of mitochondria. Further, we show that virus-like particles (VLPs), which are part of the retrotransposition cycle of Ty elements, are markedly enriched in these sites of protein aggregation. RNA interference-mediated silencing of Ty expression perturbed aggregate sequestration to mitochondria, reduced overall protein aggregation, mitigated toxicity of a Huntington's disease model, and expanded the replicative lifespan of yeast in a partially Hsp104-dependent manner. The results are in line with recent data demonstrating that VLPs might act as aging factors in mammals, including humans, and extend these findings by linking VLPs to a toxic accumulation of protein aggregates and raising the possibility that they might negatively influence neurological disease progression.

Appeal to Aggregators of Market Information in the Field of Medical Services and Protection of Honor, Dignity and Business Reputation

The development of digitalization spheres increases the value of such a resource as information. Legal regulation of aggregator sites, where information is collected and provided to a wide range of users with the ability to evaluate and rank marketable information (description of services/goods, establishment of rating indicators) is insufficient. The analysis of judicial practice and the identified problems of protection of honor, dignity and business reputation when referring to aggregators of market information require special attention in the issues of medical services. The aim and objectives of the study are to analyze the possibilities of protection of honor, dignity and business reputation of professionals providing medical services when applying to aggregators of market information – specialized websites of service consumers. Research methods: general scientific methods of cognition (comparison, description, analysis, synthesis, etc.), special-legal (legal-dogmatic, legal modeling). It should be emphasized that the process of digitalization has a significant impact on most spheres of life of society, in this regard, it was necessary to turn to communicative and anthropological approaches to analyze the impact of digital technologies on the process of development of communications in society. As a result, the conclusions were made about the recognition of the complexity of legislation, which combines norms of public and private legal nature regulating the public relations under study, the need to improve the tools of interaction between subjects in the field of digital reality (owners, operators of sites-aggregators of conjectural information and consumers of services, professionals and organizations providing medical services), the introduction of changes in the norms of legislation in order to eliminate different interpretations and possible conflicts of law.

Mechanical properties and wear performance of denture base polymethyl methacrylate reinforced with nano Al2O3

Polymethyl methacrylate (PMMA) has been widely used as a material in dentistry. The deterioration of pure PMMA denture teeth is a significant issue that can alter the vertical dimensions of dentures. This study investigates the effect of aluminum oxide (Al2O3) nano-ceramic addition as reinforcements into the heat-cure acrylic resin denture teeth. The PMMA was reinforced with Al2O3 concentrations of 1, 3, 5, and 10 wt.%. The PMMA without ceramic addition is produced for comparison purposes. The color change, densification, microhardness, and compressive properties of the produced PMMA resin and its composites were investigated to detect the effect of Al2O3 nano ceramic addition on the physical and mechanical properties. Furthermore, the microstructure was also performed using scanning electron microscopy (SEM) analysis. A chewing simulator was utilized to conduct two-body wear testing, employing a human enamel antagonist. The wear behavior of the PMMA and their composites were assessed by measuring the weight loss after submitting them to 37,500 cycles. The SEM microstructure analysis revealed sound specimens of PMMA reinforced with 0, 1, 3, and 5 wt.% Al2O3 without any porosity and micro defects using the applied production procedures. In contrast, the aggregated sites and propagation of cracks were detected for the PMMA/10 wt.% Al2O3 specimen. The densification and hardness properties of the produced PMMA composites improved with increasing the Al2O3 additions. The microhardness of PMMA/10 wt.% Al2O3 improved by around 233% compared to the PMMA matrix. The higher compressive properties were detected for the PMMA/5 wt.% Al2O3 composite specimen with ultimate compressive strength (UCS) of 54.75 MPa and yield strength (YS) of 45.6 MPa and improved than the PMMA matrix by around 98 % and 117 %, respectively. In addition, incorporating Al2O3 nano-ceramic particles into a PMMA matrix revealed a significant improvement in the wear resistance of the produced composites compared to the PMMA matrix.

Satellite tagging confirms long distance movement and fast dispersal of Patagonian toothfish (Dissostichus eleginoides) in the Southwest Atlantic

IntroductionTo better understand Patagonian toothfish (Dissostichus eleginoides) movement and habitat in the Southwest Atlantic, fifty popup satellite archival tags (PSATs) were deployed off Davis Bank on North Scotia Ridge between 2019 and 2020 on individuals ranging from 97-139 cm total length.MethodsPSATs (18 Lotek Wireless PSATFLEX and 32 Wildlife Computers MiniPAT) were programmed to detach after completing 1 to 16-month missions recording pressure (depth) and water temperature.ResultsSix tags failed to report, and among the remaining 44 reporting tags, 34 reported on schedule, up to 487 days at sea – the longest electronic tag deployment for this species to date. Although the majority of PSATs reported within 50 km from the release sites, confirming high site fidelity, 12% of tags reported more than 200 km away, showing connectivity to Shag Rocks and South Georgia in the Southern Ocean. Toothfish moved across the Antarctic Polar Front through/to areas with no fishing activities, and hence, explained the absence of any previous conventional tag recapture. A 1-month transit to the Falkland/Malvinas Plateau Basin also revealed that toothfish can attain a surprisingly high movement rate of 33 km day-1.DiscussionFishery independent examples of toothfish presence and their movement capabilities are inviting us to broaden our examination on how toothfish move around their Scotia Arc habitats and link up different regional aggregation sites in the South Atlantic.

A Ru3+-functionalized-NMOF nanozyme as an inhibitor and disaggregator of β-amyloid aggregates.

Alzheimer's disease (AD) heavily impacts human lives and is becoming serious as societies age. Inhibiting and disaggregating β-amyloid aggregates is a possible solution for AD therapy. In this study, a novel type of nanozyme based on Ru3+-chelated nanoscale metal organic frameworks (Ru3+-NMOFs), displaying strong peroxidase-like activity, was proposed as an inhibitor and disaggregator of β-amyloid aggregates. As a high concentration of hydrogen peroxide is present at the sites of β-amyloid aggregates, Ru3+-NMOFs could catalyze the conversion of hydrogen peroxide to hydroxyl radicals. Thus, these hydroxyl radicals would attack the β-amyloid chain, oxidizing it to enhance its hydrophilicity, which results in a decreased hydrophobic interaction and reduced degree of aggregation. Ru3+-NMOFs could effectively inhibit as well as disaggregate β-amyloid fibrils both in vitro and in vivo. Additionally, the reduction of the β-amyloid aggregates and the attenuation of reactive oxygen species transfer led to lower levels of inflammatory factors, which could be beneficial in alleviating AD symptoms. In a typical treatment, Ru3+-NMOFs could mitigate the paralysis of C. elegans CL2120 and elevate survival rates. This study opens a new avenue for MOF-based nanozymes as potential treatment agents for AD therapy.

Diel movements and space use of Lutjanus analis at a spawning aggregation site: evaluating the efficacy of a seasonal closed area for management

Diel movements and space use of Lutjanus analis at a spawning aggregation site: evaluating the efficacy of a seasonal closed area for management

Insights into the Relative Abundance, Life History, and Ecology of Oceanic Sharks in the Eastern Bahamas

Fisheries-independent data on the diversity, relative abundance, and demographic structure of poorly studied, threatened oceanic sharks are absent from much of the western North Atlantic Ocean, where multiple oceanic shark species have experienced significant population declines. Resource-limited management approaches require the identification of critical habitats or aggregation sites worthy of protection and enforcement. Data were collected on oceanic sharks using pelagic longline surveys, targeted baiting, and opportunistic encounters in oligotrophic open-ocean habitats of north-eastern Exuma Sound (NES), The Bahamas. The oceanic epipelagic shark community was also characterized using targeted baiting off Columbus Point, Cat Island (CI), a seamount north of San Salvador (SSSM), and the northwestern tip of Mayaguana. Pelagic longline surveys suggested that the relative abundance of sharks at NES was low (shark catch-per-unit-effort: 0.0007 sharks hook−1 h−1; 2.3 sharks per 1000 hooks). Silky sharks Carcharhinus falciformis, particularly juveniles (134 ± 39 cm stretched total length; mean ± SD STL), were the most common. Targeted baiting suggested oceanic whitetip sharks C. longimanus were abundant at CI, where large adults (245 ± 23 cm STL), most of which were females (83.8%, n = 98 of 117) that were gravid (65.7%; n = 46 of 70 assessed for pregnancy), dominated the aggregation. Many (20.5–26.5%, n = 24–31 of 117 depending on assumptions regarding tag loss) were recaptured or resighted at CI for up to five years. Silky sharks dominated catches at SSSM. Oceanic sharks, particularly adults, were sometimes caught or observed alongside short-finned pilot whales Globicephala macrorhynchus or tunas. Although The Bahamas offers threatened oceanic sharks refuge from fishing across its entire jurisdiction, these data suggest that some fixed features, including sites such as CI and potentially SSSM, are important aggregation sites with high regional conservation value and should be prioritized by fisheries managers and enforcement officials.

Coworking and local development outside metropolitan areas in Sweden

Through a mixed methods approach, this paper explores how coworking as a phenomenon manifests itself in Sweden, and, using the foundations of agglomeration economy theory as a lens, discusses what impact the occurrence of coworking spaces might have on local and regional development in Sweden's rural regions.Our findings show that the occurrence of coworking providers in Sweden is much more widespread than previously known, as there are far more spaces than popular aggregation sites suggest - our study found that for Sweden they only show 14–18 percent of the actual number of spaces available. In our interviews with members and owners, we used Duranton and Puga's (2004) pillars for agglomeration as a sorting mechanism, which showed that sentiments that fit the themes “matching”, “sharing” and “learning” crop up frequently when respondents explain their experiences. There is reason to go forward from this first, small study to explore how agglomeration economies at the micro level may influence surrounding society and regional economic growth in rural regions.We argue that the emergence of these spaces in rural regions might be a factor in the development of local economies by enabling agglomeration economies at the micro level. We also make the suggestion that gaining accurate information about the number and characteristics of coworking spaces in rural regions will allow for better informed policy decisions and labor market legislation when it comes to regional development.

Phase-Noise Characterization in Stable Optical Frequency Transfer over Free Space and Fiber Link Testbeds

Time and frequency metrology depends on stable oscillators in both radio-frequency and optical domains. With the increased complexity of the highly precise oscillators also came the demand for delivering the oscillators’ harmonic signals between delocalized sites for comparison, aggregation, or other purposes. Besides the traditional optical fiber networks, free-space optical links present an alternative tool for disseminating stable sources’ output. We present a pilot experiment of phase-coherent optical frequency transfer using a free-space optical link testbed. The experiment performed on a 30 m long link demonstrates the phase-noise parameters in a free-space optical channel under atmospheric turbulence conditions, and it studies the impact of active MEMS mirror stabilization of the received optical wave positioning on the resulting transfer’s performance. Our results indicate that a well-configured MEMS mirror beam stabilization significantly enhances fractional frequency stability, achieving the−14th-order level for integration times over 30 s.

Making ties and social identities: Drawing connections between PPNB communities as based on shell bead typology.

People tend to belong to multiple social circles, which construct and reflect a person's social identity. Group affiliation is embodied and may be expressed by personal adornment. Personal adornment in general has multiple functions in human societies, among them the assimilation and transmission of different aspects of personal and collective, social and cultural identity. Beads in general, including shell beads, often constitute parcels of composite adornment, and as such are used in different configurations to portray these messages. The shared use of similar bead types by different individuals and communities indicates the mutual affiliation of the sharing parties to the same cultural circles and reflects social ties and relationships. The Pre-Pottery Neolithic B (PPNB) period in the Levant is a time of pivotal changes to human lifeways necessitating profound adjustments in all aspects of life, including social relations and networks. Here we use the shell bead assemblage from the cultic-mortuary aggregation site of Kfar HaHoresh, in comparison to shell bead assemblages from multiple other sites in the Levant, as a proxy for the exploration of local and regional networks and connections between PPNB communities. Multivariate analyses of shell bead type distribution patterns across the Levant demonstrate that some types were widely shared among different communities, characterising different geographic regions, while others were rare or unique, highlighting relationships between sites and regions, which are occasionally independent of geographic proximity. Specific occurrences of shared shell bead types between Kfar HaHoresh and compared sites further illuminate the web of connections between PPNB communities in the Levant and the varying breadths of sharing-patterns reflect the hierarchical nature of the underlying social circles. Outlining these widening social affiliations sheds light on the complex structure of Neolithic social identity.

Microstructure and bending behavior of Ti/Al laminated composites reinforced with high-entropy alloy particles

Ti/Al laminated composites embedded with Al0.5CoCrFeNi high entropy alloy particles were prepared by vacuum hot press sintering process at temperatures of 660 °C and 730 °C. The microstructure of the material was initially examined using XRD, SEM, EDS, EBSD, and TEM techniques. The results of microstructural characterisation show that Al3Ti is the only newly generated phase in the materials prepared at two temperatures. The Al3Ti generated at the temperature of 660 °C is concentrated at the Ti/Al interface position. The Al3Ti generated at a temperature of 730 °C is dispersed in the Al matrix, leading to the formation of numerous Al3Ti/Al interfaces. The residual HEA particles were observed at the sites of oxide aggregation, potentially enhancing the connectivity of the weak interfaces. Following that, the flexural strength and fracture toughness of the composites were evaluated. The results indicate that the materials prepared at a temperature of 730 °C exhibit superior properties. The flexural strength perpendicular to the layer direction reaches 515.89 MPa, while the flexural strength parallel to the layer direction reaches 487.1 MPa. These findings demonstrate clear anisotropy in the flexural performance. Additionally, the material exhibits excellent resistance to crack extension, with a fracture toughness of 32.67 MPa√m.

Spatial and temporal characterization of a recurrent scalloped hammerhead shark Sphyrna lewini aggregation using drones

Abstract Scalloped hammerhead sharks Sphyrna lewini are threatened throughout their distribution. The species forms aggregations, which can potentially increase its vulnerability to human impacts. Identification and characterization of aggregation sites are essential to inform management and conservation. We used drones to characterize the spatial and temporal distribution of a recently documented scalloped hammerhead aggregation within the Shoalwater Islands Marine Park, in southwest Western Australia. A total of 267 drone transects were conducted across the Austral summers of 2019–2020 and 2020–2021. The presence or absence of the sharks was examined in relation to fine scale patterns in habitat type, environmental conditions, and the occurrence of human activities. Scalloped hammerhead sharks had a small spatial and temporal distribution within the study area. Their presence in the study area was higher on days associated with higher lunar illumination phases, which could indicate that the aggregation site is potentially acting as a refuge for resting and/or predatory avoidance. The extent to which human interactions affect scalloped hammerhead sharks at the aggregation site remains unclear and raises questions about the adequacy of management measures at Shoalwater Islands Marine Park. Recommendations are proposed to limit potential impacts, such as establishing spatiotemporal fishing restrictions and regulating public interactions.

Characterization and temporal patterns of red hind grouper, Epinephelus guttatus, choruses at a single aggregation site over a 10-year period

Characterization and temporal patterns of red hind grouper, Epinephelus guttatus, choruses at a single aggregation site over a 10-year period

The essential habitat role of a unique coastal inlet for a widely distributed apex predator.

Essential habitats support specific functions for species, such as reproduction, feeding or refuge. For highly mobile aquatic species, identifying essential habitats within the wider distribution range is central to understanding species ecology, and underpinning effective management plans. This study examined the movement and space use patterns of sevengill sharks (Notorynchus cepedianus) in Caleta Valdés (CV), a unique coastal habitat in northern Patagonia, Argentina. Seasonal residency patterns of sharks were evident, with higher detectability in late spring and early summer and lower during autumn and winter. The overlap between the residency patterns of sharks and their prey, elephant seals, suggests that CV functions as a seasonal feeding aggregation site for N. cepedianus. The study also found sexual differences in movement behaviour, with males performing abrupt departures from CV and showing increased roaming with the presence of more sharks, and maximum detection probability at high tide. These movements could be related to different feeding strategies between sexes or mate-searching behaviour, suggesting that CV may also be essential for reproduction. Overall, this study highlights the importance of coastal sites as essential habitats for N. cepedianus and deepens our understanding of the ecological role of this apex predator in marine ecosystems.

Water loss, not overheating, limits the activity period of an endothermic Sonoran Desert bee

Abstract Desert animals must manage the physiological stress caused by heat and desiccation; evaporative heat loss mitigates overheating but exacerbates water stress. Small endothermic flying insects may be particularly vulnerable to overheating and water stress as a result of high surface area to volume ratios, but we lack quantitative understanding of the relative magnitude of these abiotic stressors in flying desert invertebrates, despite their ecological importance. During the hottest and driest weeks of year, many thousands of males of the Sonoran Desert digger bee (Centris caesalpiniae) flew near‐continuously at elevated thorax temperatures for hours at mating aggregation sites, while fighting other males and digging for females. To determine whether incapacitating high temperatures or water loss limited the activity period of male C. caesalpiniae, we assessed wet and dry body mass and water content through the activity period, flight durations using mark–recapture methods, crop volume and sugar content, microclimate selection, water balance during flight, critical water content and maximum critical temperature. Body masses and sizes of males declined through the morning. Body water content scaled isometrically with total body wet mass. Crop volume and sugar content did not vary throughout the day or with bee size. Maximum critical temperature during flight was 51°C for large‐morph C. caesalpiniae males, similar to those measured for other bees, and well above body temperatures reached in the field, suggesting that avoidance of overheating does not limit activity in this desert bee. The critical water content of Centris bees averaged 50%, at the low end of those measured for other bees. Measures of net water loss rate indicated that males approached lethal water loss limits within 4 h, a duration in the range of measured daily flight activity, suggesting that desiccation tolerance limits activity. Remarkably, male C. caesalpiniae were not observed to forage at floral or water sources during the activity period, yet they returned over multiple days, suggesting that these males have a mechanism to rehydrate when not at the mating aggregation. Read the free Plain Language Summary for this article on the Journal blog.

Spawning aggregations of checkered snapper (Lutjanus decussatus) and blackspot snapper (L. fulviflamma): seasonality, lunar-phase periodicity and spatial distribution within spawning ground.

Snappers (family Lutjanidae) are important fisheries target species and some species are known to form spawning aggregations at particular spawning grounds. The present study investigated the ecological characteristics of fish aggregations of two snapper species (checkered snapper Lutjanus decussatus and blackspot snapper L. fulviflamma) that form at a particular site. Specifically, the aims were to clarify (1) seasonality and lunar-phase periodicity of fish aggregation formation, (2) fine-scale spatial distribution of fish density (spatial variations of fish density at intervals of several-tens meters) within the aggregation site, (3) size and age frequency distributions of fishes in the aggregation site, (4) gonad development, (5) to compare fish abundance between inside and outside the aggregation site, and (6) to verify that fish aggregations of the two snapper species were spawning aggregation. Underwater observations using a 600m×5m transect revealed that greater fish abundance of Lutjanus decussatus was found monthly between May and October, and clear positive peaks in the fish abundance were found only around the last-quarter moon. This lunar-related periodicity in the increase of fish abundance was confirmed by a time-series analysis (correlogram). Within the aggregation site, L. decussatus showed a relatively uniform distribution. In contrast, greater fish abundance of L. fulviflamma was found monthly between April and October, and clear positive peaks in the fish abundance were found around the last-quarter moon (April, May, June and October) or new moon (July, August and September). This lunar-related periodicity was also confirmed by correlogram. Lutjanus fulviflamma showed a relatively clumped distribution within the aggregation site. Most females of the two species in the aggregation site had hydrated eggs, indicating that the two species form aggregations for reproduction. The two species, although occurring simultaneously, are considered to form aggregations of conspecifics only. For L. decussatus, average fork length and age of males and females were 229.2 mm and 243.9 mm and 9.4 years and 8.1 years, respectively. For L. fulviflamma, average fork length and age of males and females were 233.9 mm and 246.9 mm and 6.8 years and 8.1 years, respectively. Fish abundance inside the aggregation site was 266.8-fold and 141557.1-fold greater than those outside the aggregation site for L. decussatus and L. fulviflamma, respectively. These results showed that (1) fish aggregation formation of the two snapper species was predictably repeated in particular months and lunar-phase, (2) it was predictably found at the particular site, (3) the fish abundance in the aggregation site markedly exceeded the fish abundance outside the aggregation site, and (4) the two species form aggregations for reproduction. Therefore, it is suggested that the fish aggregations for the two species can be regarded as spawning aggregations.