Null models for understand intertidal decapods communities in North Patagonian beach (Pelluhuin, 41°S, Chile)

Null models for understand intertidal decapods communities in North Patagonian beach (Pelluhuin, 41°S, Chile) | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Null models for understand intertidal decapods communities in North Patagonian beach (Pelluhuin, 41°S, Chile) Eliana Ibáñez-Arancibia, Patricio De los Rios-Escalante, Farhana S. Ghory, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5921609/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The intertidal decapods in continental Chile are characterized by its species sharing with Peruvian coast along practically all coast, being coexisting species that has not studied with details its interspecific interactions. The aim of the present study is apply null models for understand if the intertidal decapod community is random or not-random. The results revealed that species associations were random, due probably to many species repeated in samples, and the niche sharing results revealed that species reported do not share niche, and in consequence there is not interspecific competition. The obtained results partially agree with other similar observations for Chilean coast, and it would be explained due the oceanographic conditions. intertidal decapods null models northern Patagonia rocky shore Figures Figure 1 Figure 2 Figure 3 INTRODUCTION The intertidal decapods in Chilean coast is characterized by the presence of shared species with Peruvian coast along all continental territory, and subantarctic species in southern latitudes [1,2]. The species richness is high in northern Chilean coast (18–30°S) due the exposure of Humboldt stream that generates upwelling process that causes high productivity environments [3]. Whereas in northern Patagonia (38–41°S), the presence of coast with marked wave exposure and low productivity conditions does not allow high species richness [2,4]. Finally in Patagonia, at south of 41° latitude the presence of inner seas and relative low human intervention allow the presence of high crustacean diversity, and these crustacean communities are important for recycle of dead matter and important prey for littoral fishes important in local artisanal fisheries [1,2]. The Patagonian is characterized by the presence of inner seas that are protected to waves, with marked tidal variations, with nutrients inputs from surrounding basin, that is characterized by native perennial forests, and relative low human intervention, where it is possible found intertidal and sub-tidal crustacean communities that are important as prey for littoral fishes important for local fisheries and economy of rural communities [5,6]. In this scenario, it is necessary to study if the decapod community has a structured pattern, considering the situation of relative low pristine conditions. In order to study communities, one of the focus areas is to use null models, which are based on the previous condition that the community is either random, or that there is no structure [7]. These models are more robust than other kinds of statistical analysis [8,9]. A null model is applied in this study in order to better understand the ecology of intertidal decapod community on northern Patagonian beach. MATERIAL AND METHODS Study site: the site corresponds to a sandy beach with small rounded stones called Pelluhuin beach (41°29’13’’S; 72°54’16’’W; Fig. 1 ) at four km at south of Puerto Montt, in a semi-rural zone, the site was visited in 24 February 2020, during low tide. Data collection: the first species identification was done in situ were based on literature descriptions [10], and taxonomic status was confirmed by WORMS [11]. Random quadrants (10*10 cm) were released in studied sites (n = 90 for each site) during low tide, it was considering this size of quadrant on the basis of the fast movements of littoral decapods [2], and this size of quadrant would be more adequate for fast movement species and the irregular conformation of the site rounded rocks, random quadrants along low tide level on the basis of description of literature for similar ecosystems [2, 12, 13]. Manually entered data were recorded in a field copybook. A community is structured by competition when the C-score is significantly larger than expected by chance [7,8,9]. Consequently, we compared co-occurrence patterns with null expectations via simulation using statistical null models Fixed-Fixed [14]. In this model, the row and column sums of the matrix are preserved. Thus, each random community contains the same number of species as the original community (fixed column), and each species occurs with the same frequency as in the original community (fixed row). In fixed-equiprobable algorithm, only the row sums are fixed, and the columns are treated as equiprobable, this null model treats all the samples (columns) as equally suitable for all species [8,9]. In the fixed-proportional algorithm, the species occurrence totals are maintained as in the original community, and the probability that a species occurs in a sample (= column) is proportional to the column total for that sample [8,9]. The null model analyses were performed using the software R [15] and the package EcosimR [14,16]. For niche overlap analysis, an individual matrix was built in which rows and columns represented species and sites, respectively. This matrix was used to test if the niche overlap significantly differed from the corresponding value under the null hypothesis (random assemblage). These analyses were applied to data from the second field period and were based on Pianka index. The models show the probability of niche sharing compared to the niche overlap of the theoretically simulated community [14]. The niche amplitude can be retained or reshuffled when it is retained it preserves the specialization of each species. In contrast, when it is reshuffled, it uses a wide utilization gradient of specialisation. Furthermore, zero participation in the observed matrix can be maintained or omitted. In the present study, we used the RA3 algorithm [14,16]. This algorithm retains the amplitude and reshuffles the zero conditions [14]. This null model analysis was carried out using the software R [15] and the package EcosimR [14,16]. RESULTS AND DISCUSSION The results denoted the presence of five decapods species (Table 1 ; Fig. 2 ): Cyclograpsus cinereus Dana, 1851, Cancer porteri Rathbun, 1930, Betaeus truncatus Dana, 1852; Petrolisthes granulosus (Guerin, 1835) and Homolaspis plana (H. Milne-Edwards, 1835). The results denoted a density variable between 0.033 ind/0.01m2 ( C. cinereus and C. porteri ; Table 1 ) and 0.122 ind/0.01m2 ( P. granulosus , Table 1 ).The results of null models revealed that species associations were random for fixed-fixed, whereas denoted structured pattern for fixed-equiprobable and fixed proportional simulation models (Table 2 , Fig. 3 ), that would be due many repeated species by samples, whereas the results of niche sharing revealed that species would not share ecological niche, and in consequence it would have not interspecific competition (Table 2 , Fig. 3 ). Table 1 Results of mean ± standard deviation by grid (0.01 m 2 ; n = 90) for decapods species reported at studied site. Species reported Mean ± standard deviation Homolaspis plana (H. Milne Edwards, 1834) 0.256 ± 0.487 Petrolisthes granulosus (Guérin, 1835) 0.122 ± 0.445 Cyclograpsus cinereus Dana, 1851 0.033 ± 0.181 Betaeus truncatus Dana, 1852 0.044 ± 0.207 Cancer porteri Rathbun, 1930 0.033 ± 0.181 Table 2 Results of null models for species reported at studied site. Species co-occurrence null models Model Observed index Mean index Standard effect size Variance P Fixed-fixed 49.100 49.100 NaN 0.000 0.999 Fixed equiprobable 49.100 26.958 3.610 37.621 0.003* Fixed-proportional 49.100 37.669 2.792 17.543 < 0.001* Niche sharing null model Model Observed index Mean index Standard effect size Variance P Pianka index 0.065 0.000 -2.141 < 0.001 0.999 Note: for species co-occurrence null models P value upper than 0,05 revealed the random presence in species associations, whereas P values lower than 0,05 (*) revealed the presence of structured patterns in species associations. For Niche sharing P value upper than 0.05 revealed that species don’t share ecological niche. The exposed results revealed that species composition is similar to descriptions for exposed littoral coast in northern Patagonia (38–41°S; [17]) where the species co-occurrence revealed random presence, that in consequence would reveal the absence of species interactions [8,9], these results would be supported by niche sharing null model obtained in the present study. Nevertheless, the results based on size overlap null models, on intertidal decapods in central Chilean coast [18] and two different sites in exposed coast in northern and southern Chile [17], revealed that intertidal decapods communities have size overlap, and in consequence would share ecological niche, that in first instance would not support the results obtained in the present study. A possible cause that would explain this contradiction between null models results for explain the intertidal decapod community would be probably the differences in oceanographic characteristics mainly in term of substrate conditions, that would provide shelter for intertidal decapods [3]. The results obtained in the present study would reveal that it would be necessary more studies for understand the interspecific interactions between intertidal decapods along Chilean coast. Declarations ACKNOWLEDGMENTS The present study was funded by project MECESUP UCT 0804. The author express their gratitude to M.I. and S.M.A. for their valuable suggestions for improve the manuscript. ETHICAL STATEMENT: Funding: Project MECESUP UCT 0804 Conflict of Interest: NA Ethical approval: NA Informed consent: NA Author contribution: EIA: contributed to field works. PDE contributed direct the research activities and redaction of manuscript. FSG: contributed to redaction of manuscript. CE: contributed to data analysis Data Availability Statement: data are available from PDE (contact directly to him) References Santelices B. Algas marinas de Chile. Distribución, ecología, utilización, diversidad. Ediciones Pontificia Universidad Católica de Chile, Santiago de Chile. 1992; Retamal MA, Moyano HI, Zoogeography of Chilean marine and freshwater decapod crustaceans. Latin American J. Aq. Res., 2010, 38: 302-328. https://doi.org/10.3856/vol38-issue3-fulltext-1 De los Rios-Escalante P, Esse C, Retamal MA, Zúñiga O, Fajardo M, Ghory F. Spatial distribution of Cyclograpsus cinereus Dana 1851 on the Rocky Shores of Antofagasta (23°27’ S, Chile). Diversity, 2022, 14, 418. https://doi.org/10.3390/d14060418 De los Ríos P, Figueroa-Muñoz G, Kies F. Presence of Cyrtograpsus angulatus Dana, 1851 (Decapoda, Brachyura) on the Chilean Northern Patagonian coast. Crustaceana, 2018, 91: 353-361. https://doi.org/10.1163/15685403-00003767 Figueroa-Muñoz G, Retamal M, De Los Ríos P, Esse C, Pérez-Schultheiss J, Vega-Aguayo R, Boyero L, Correa-Araneda F. Scavenging crustacean fauna in the Chilean Patagonian sea. Sci. Rep., 2020, 10, 5940. https://doi.org/10.1038/s41598-020-62570-2 Figueroa-Muñoz G, Molinet C, Díaz M, De los Ríos-Escalante P. Decapods associated with the Southern king crab ( Lithodes santolla ) fishery in Central Patagonia (44◦ S, Chile). J. Mar. Sci. Eng., 2021. 9: 1353. https://doi.org/10.3390/jmse9121353 Gotelli NJ. Null model analysis of species co-occurrence patterns. Ecology. 2020, 81: 2606-2621. https://doi.org/10.1890/0012-9658(2000)081[2606:NMAOSC]2.0.CO;2 Tiho S, Johens G. Co-occurrence of earthworms in urban surroundings: a null model analysis of community structure. European J. Soil Biol., 2007, 43: 84-90. https://doi.org/10.1016/j.ejsobi.2006.10.004 Tondoh JE. Seasonal changes in earthworm diversity and community structure in Central Côte d’Ivoire. European J. Soil Biol., 2006, 42: supplement, 1, pp. s334-s340. https://doi.org/10.1016/j.ejsobi.2006.09.003 Retamal M. Los Decápodos Chilenos. CD-Rom. ETI (Amsterdam). Universidad de Concepción; Springer: Berlin/Heidelberg, Germany. 2000. WORMS Editorial Board. World Register of Marine Species. Available from https://www.marinespecies.org (Visited: 10 th May 2024). 2024 Underwood AJ, Chapman MG. Design and analysis in benthic surveys in environmental sampling. In: Eleftheriou A, McIntyre A, (Eds). Methods for the Study of Marine Benthos. Blackwell Science: Oxford, UK. pp. 1–42. 2005. Manriquez PH. Muestreo y análisis de comunidades intermareales de fondos duros. In: Castilla JC, Fariña JM, Caamaño A, Eds. Programas de Monitoreo del Medio Marítimo Costero. Diseños Experimentales, Muestreos, Métodos de Análisis y Estadística Asociada; Ediciones Pontificia Universidad Católica de Chile: Santiago, Chile; pp. 233–256. 2021 Gotelli NJ, Ellison AM. EcoSimR 1.00. Available at: http://www.uvm.edu/~ngotelli/EcoSim/EcoSim.html [accessed 05-Sep-2023] R Development Core Team. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. 2025 Carvajal-Quintero JD, Escobar F, Alvarado F, Villa-Navarro FA, Jaramillo-Villa U, Maldonado-Ocampo JA. Variation in freshwater fish assemblages along a regional elevation gradient in the northern Andes, Colombia. Ecol Evol, 2015, 2: 2608-2620. https://doi.org/10.1002/ece3.1539 De los Ríos-Escalante P, Figueroa-Muñoz G, Retamal MA, Vega-Aguayo R, Esse C. Size overlap in intertidal decapod communities along the Chilean coast. Sci Mar, 2020, 84: 151-154. https://doi.org/10.3989/scimar.04973.14A Andrade D, Ventura MJ, Stella C, De los Ríos-Escalante P. Size overlap in intertidal decapod communities on a central Chilean rocky beach (El Quisco, 32°24’S, Valparaíso region, Chile). Crustaceana, 2022, 95: 489-495. https://doi.org/10.1163/15685403-bja10203 Additional Declarations No competing interests reported. Supplementary Files Supplementarymaterial.xlsx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5921609","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":437842086,"identity":"41532e2a-4a33-4a14-ae50-4d013f1f94a1","order_by":0,"name":"Eliana Ibáñez-Arancibia","email":"","orcid":"","institution":"Universidad de la Frontera","correspondingAuthor":false,"prefix":"","firstName":"Eliana","middleName":"","lastName":"Ibáñez-Arancibia","suffix":""},{"id":437842089,"identity":"7e259e2b-b821-4a69-8fa1-5f5a4d85769d","order_by":1,"name":"Patricio De los Rios-Escalante","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAkUlEQVRIiWNgGAWjYFACxgYGhgoI6wAJWs4wMPAAmcRqAelqI0WLufThxoc/5x2Wt2dgfkCcFsu+xGZj3m2HDXsY2AyI02JwhrFNmnHb4QQeoNOI1yL5cw6pWiR4G0jRYtnD2GzMcyzdsOcwsX4x52F/+PBHjbU8e3vzwwfEOQzOYiZKPYqWUTAKRsEoGAW4AACS6irpK1LefgAAAABJRU5ErkJggg==","orcid":"","institution":"Universidad Católica de Temuco","correspondingAuthor":true,"prefix":"","firstName":"Patricio","middleName":"De los","lastName":"Rios-Escalante","suffix":""},{"id":437842095,"identity":"ae85db8e-8743-4db7-ada2-edcf4a302c8f","order_by":2,"name":"Farhana S. Ghory","email":"","orcid":"","institution":"University of Karachi · Marine Reference Collection \u0026 Resource Centre","correspondingAuthor":false,"prefix":"","firstName":"Farhana","middleName":"S.","lastName":"Ghory","suffix":""},{"id":437842096,"identity":"695bd8f1-5de3-4e75-8925-29440f4953e1","order_by":3,"name":"Carlos Esse","email":"","orcid":"","institution":"Universidad Autónoma de Chile, Instituto Iberoamericano de Desarrollo Sostenible – IIDS, Unidad de Cambio Climático y Medio Ambiente – UCCMA","correspondingAuthor":false,"prefix":"","firstName":"Carlos","middleName":"","lastName":"Esse","suffix":""}],"badges":[],"createdAt":"2025-01-29 03:38:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5921609/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5921609/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":79891599,"identity":"f7021858-0342-42d1-ae35-337db57aa0ea","added_by":"auto","created_at":"2025-04-04 07:44:14","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":754975,"visible":true,"origin":"","legend":"\u003cp\u003eMap and photograph of studied site\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5921609/v1/9277910fff283a5c244b4987.png"},{"id":79891818,"identity":"205fb8bd-0adf-4f76-ab81-f86b714dfd67","added_by":"auto","created_at":"2025-04-04 07:52:14","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":431913,"visible":true,"origin":"","legend":"\u003cp\u003ePhotograph of species included in the present study.(upper left; \u003cem\u003eHomolaspis plana\u003c/em\u003e; upper right: \u003cem\u003ePetrolisthes granulosus\u003c/em\u003e; center left: \u003cem\u003eCyclograpsus cinereus\u003c/em\u003e; center right: \u003cem\u003eBetaeus truncates\u003c/em\u003e; low: \u003cem\u003eCancer porter\u003c/em\u003e). (Source; iNaturalist)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5921609/v1/4be4df1d555d4b4126df2a70.png"},{"id":79891613,"identity":"6ca59474-dc15-4ed3-8ca9-2545fbbcbf9c","added_by":"auto","created_at":"2025-04-04 07:44:17","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":99980,"visible":true,"origin":"","legend":"\u003cp\u003eResults of species co-occurrence null models (A: species co-occurrence: fixed-fixed; B: species co-occurrence: fixed-equiprobable; C: species co-occurrence: fixed proportional; D: Niche sharing). The red line revealed the mean index, in comparison to the observed results (see bar graphs in blue).\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5921609/v1/8f645e4c9c2ba83baed6a986.png"},{"id":81258257,"identity":"3df41912-ec92-44de-8478-341fea3d34ce","added_by":"auto","created_at":"2025-04-24 05:32:41","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2137565,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5921609/v1/1d4df056-6227-4e48-aa69-c3224d816837.pdf"},{"id":79892278,"identity":"c194dbb7-6e20-4b80-ab01-564d1525d17b","added_by":"auto","created_at":"2025-04-04 08:00:14","extension":"xlsx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":11259,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarymaterial.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-5921609/v1/cbd6c8b6097d49818479be88.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Null models for understand intertidal decapods communities in North Patagonian beach (Pelluhuin, 41°S, Chile)","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eThe intertidal decapods in Chilean coast is characterized by the presence of shared species with Peruvian coast along all continental territory, and subantarctic species in southern latitudes [1,2]. The species richness is high in northern Chilean coast (18\u0026ndash;30\u0026deg;S) due the exposure of Humboldt stream that generates upwelling process that causes high productivity environments [3]. Whereas in northern Patagonia (38\u0026ndash;41\u0026deg;S), the presence of coast with marked wave exposure and low productivity conditions does not allow high species richness [2,4]. Finally in Patagonia, at south of 41\u0026deg; latitude the presence of inner seas and relative low human intervention allow the presence of high crustacean diversity, and these crustacean communities are important for recycle of dead matter and important prey for littoral fishes important in local artisanal fisheries [1,2].\u003c/p\u003e \u003cp\u003eThe Patagonian is characterized by the presence of inner seas that are protected to waves, with marked tidal variations, with nutrients inputs from surrounding basin, that is characterized by native perennial forests, and relative low human intervention, where it is possible found intertidal and sub-tidal crustacean communities that are important as prey for littoral fishes important for local fisheries and economy of rural communities [5,6]. In this scenario, it is necessary to study if the decapod community has a structured pattern, considering the situation of relative low pristine conditions. In order to study communities, one of the focus areas is to use null models, which are based on the previous condition that the community is either random, or that there is no structure [7]. These models are more robust than other kinds of statistical analysis [8,9]. A null model is applied in this study in order to better understand the ecology of intertidal decapod community on northern Patagonian beach.\u003c/p\u003e"},{"header":"MATERIAL AND METHODS","content":"\u003cp\u003eStudy site: the site corresponds to a sandy beach with small rounded stones called Pelluhuin beach (41\u0026deg;29\u0026rsquo;13\u0026rsquo;\u0026rsquo;S; 72\u0026deg;54\u0026rsquo;16\u0026rsquo;\u0026rsquo;W; Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) at four km at south of Puerto Montt, in a semi-rural zone, the site was visited in 24 February 2020, during low tide.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eData collection: the first species identification was done in situ were based on literature descriptions [10], and taxonomic status was confirmed by WORMS [11]. Random quadrants (10*10 cm) were released in studied sites (n\u0026thinsp;=\u0026thinsp;90 for each site) during low tide, it was considering this size of quadrant on the basis of the fast movements of littoral decapods [2], and this size of quadrant would be more adequate for fast movement species and the irregular conformation of the site rounded rocks, random quadrants along low tide level on the basis of description of literature for similar ecosystems [2, 12, 13]. Manually entered data were recorded in a field copybook.\u003c/p\u003e \u003cp\u003eA community is structured by competition when the C-score is significantly larger than expected by chance [7,8,9]. Consequently, we compared co-occurrence patterns with null expectations via simulation using statistical null models Fixed-Fixed [14]. In this model, the row and column sums of the matrix are preserved. Thus, each random community contains the same number of species as the original community (fixed column), and each species occurs with the same frequency as in the original community (fixed row). In fixed-equiprobable algorithm, only the row sums are fixed, and the columns are treated as equiprobable, this null model treats all the samples (columns) as equally suitable for all species [8,9]. In the fixed-proportional algorithm, the species occurrence totals are maintained as in the original community, and the probability that a species occurs in a sample (=\u0026thinsp;column) is proportional to the column total for that sample [8,9]. The null model analyses were performed using the software R [15] and the package EcosimR [14,16].\u003c/p\u003e \u003cp\u003eFor niche overlap analysis, an individual matrix was built in which rows and columns represented species and sites, respectively. This matrix was used to test if the niche overlap significantly differed from the corresponding value under the null hypothesis (random assemblage). These analyses were applied to data from the second field period and were based on Pianka index. The models show the probability of niche sharing compared to the niche overlap of the theoretically simulated community [14]. The niche amplitude can be retained or reshuffled when it is retained it preserves the specialization of each species.\u003c/p\u003e \u003cp\u003eIn contrast, when it is reshuffled, it uses a wide utilization gradient of specialisation. Furthermore, zero participation in the observed matrix can be maintained or omitted. In the present study, we used the RA3 algorithm [14,16]. This algorithm retains the amplitude and reshuffles the zero conditions [14]. This null model analysis was carried out using the software R [15] and the package EcosimR [14,16].\u003c/p\u003e"},{"header":"RESULTS AND DISCUSSION","content":"\u003cp\u003eThe results denoted the presence of five decapods species (Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e; Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e): \u003cem\u003eCyclograpsus cinereus\u003c/em\u003e Dana, 1851, \u003cem\u003eCancer porteri\u003c/em\u003e Rathbun, 1930, \u003cem\u003eBetaeus truncatus\u003c/em\u003e Dana, 1852; \u003cem\u003ePetrolisthes granulosus\u003c/em\u003e (Guerin, 1835) and \u003cem\u003eHomolaspis plana\u003c/em\u003e (H. Milne-Edwards, 1835). The results denoted a density variable between 0.033 ind/0.01m2 (\u003cem\u003eC. cinereus\u003c/em\u003e and \u003cem\u003eC. porteri\u003c/em\u003e; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) and 0.122 ind/0.01m2 (\u003cem\u003eP. granulosus\u003c/em\u003e, Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).The results of null models revealed that species associations were random for fixed-fixed, whereas denoted structured pattern for fixed-equiprobable and fixed proportional simulation models (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), that would be due many repeated species by samples, whereas the results of niche sharing revealed that species would not share ecological niche, and in consequence it would have not interspecific competition (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eResults of mean\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;standard deviation by grid (0.01 m\u003csup\u003e2\u003c/sup\u003e; n\u0026thinsp;=\u0026thinsp;90) for decapods species reported at studied site.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSpecies reported\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;standard deviation\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eHomolaspis plana\u003c/em\u003e (H. Milne Edwards, 1834)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.256\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;0.487\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003ePetrolisthes granulosus\u003c/em\u003e(Gu\u0026eacute;rin, 1835)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.122\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;0.445\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eCyclograpsus cinereus\u003c/em\u003e Dana, 1851\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.033\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;0.181\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eBetaeus truncatus\u003c/em\u003e Dana, 1852\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.044\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;0.207\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eCancer porteri\u003c/em\u003e Rathbun, 1930\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.033\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026plusmn;\u003c/span\u003e\u0026thinsp;0.181\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eResults of null models for species reported at studied site.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eSpecies co-occurrence null models\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModel\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eObserved index\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMean index\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eStandard effect size\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVariance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFixed-fixed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e49.100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e49.100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNaN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.999\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFixed equiprobable\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e49.100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26.958\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.610\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e37.621\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.003*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFixed-proportional\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e49.100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37.669\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.792\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e17.543\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eNiche sharing null model\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModel\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eObserved index\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMean index\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eStandard effect size\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVariance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePianka index\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.065\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-2.141\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.999\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eNote: for species co-occurrence null models P value upper than 0,05 revealed the random presence in species associations, whereas P values lower than 0,05 (*) revealed the presence of structured patterns in species associations. For Niche sharing P value upper than 0.05 revealed that species don\u0026rsquo;t share ecological niche.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe exposed results revealed that species composition is similar to descriptions for exposed littoral coast in northern Patagonia (38\u0026ndash;41\u0026deg;S; [17]) where the species co-occurrence revealed random presence, that in consequence would reveal the absence of species interactions [8,9], these results would be supported by niche sharing null model obtained in the present study. Nevertheless, the results based on size overlap null models, on intertidal decapods in central Chilean coast [18] and two different sites in exposed coast in northern and southern Chile [17], revealed that intertidal decapods communities have size overlap, and in consequence would share ecological niche, that in first instance would not support the results obtained in the present study. A possible cause that would explain this contradiction between null models results for explain the intertidal decapod community would be probably the differences in oceanographic characteristics mainly in term of substrate conditions, that would provide shelter for intertidal decapods [3]. The results obtained in the present study would reveal that it would be necessary more studies for understand the interspecific interactions between intertidal decapods along Chilean coast.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eACKNOWLEDGMENTS\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe present study was funded by project MECESUP UCT 0804. The author express their gratitude to M.I. and S.M.A. for their valuable suggestions for improve the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eETHICAL STATEMENT:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFunding: Project MECESUP UCT 0804\u003c/p\u003e\n\u003cp\u003eConflict of Interest: NA\u003c/p\u003e\n\u003cp\u003eEthical approval: NA\u003c/p\u003e\n\u003cp\u003eInformed consent: NA\u003c/p\u003e\n\u003cp\u003eAuthor contribution: EIA: contributed to field works. PDE contributed direct the research activities and redaction of manuscript. FSG: contributed to redaction of manuscript. CE: contributed to data analysis\u003c/p\u003e\n\u003cp\u003eData Availability Statement: data are available from PDE (contact directly to him)\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSantelices B. Algas marinas de Chile. Distribuci\u0026oacute;n, ecolog\u0026iacute;a, utilizaci\u0026oacute;n, diversidad. Ediciones Pontificia Universidad Cat\u0026oacute;lica de Chile, Santiago de Chile. 1992;\u003c/li\u003e\n\u003cli\u003eRetamal MA, Moyano HI, Zoogeography of Chilean marine and freshwater decapod crustaceans. Latin American J. Aq. Res., 2010, 38: 302-328. https://doi.org/10.3856/vol38-issue3-fulltext-1\u003c/li\u003e\n\u003cli\u003eDe los Rios-Escalante P, Esse C, Retamal MA, Z\u0026uacute;\u0026ntilde;iga O, Fajardo M, Ghory F. Spatial distribution of \u003cem\u003eCyclograpsus cinereus\u003c/em\u003e Dana 1851 on the Rocky Shores of Antofagasta (23\u0026deg;27\u0026rsquo; S, Chile). Diversity, 2022, 14, 418. https://doi.org/10.3390/d14060418\u003c/li\u003e\n\u003cli\u003eDe los R\u0026iacute;os P, Figueroa-Mu\u0026ntilde;oz G, Kies F. Presence of \u003cem\u003eCyrtograpsus angulatus\u003c/em\u003e Dana, 1851 (Decapoda, Brachyura) on the Chilean Northern Patagonian coast. Crustaceana, 2018, 91: 353-361. https://doi.org/10.1163/15685403-00003767\u003c/li\u003e\n\u003cli\u003eFigueroa-Mu\u0026ntilde;oz G, Retamal M, De Los R\u0026iacute;os P, Esse C, P\u0026eacute;rez-Schultheiss J, Vega-Aguayo R, Boyero L, Correa-Araneda F. Scavenging crustacean fauna in the Chilean Patagonian sea. Sci. Rep., 2020, 10, 5940. https://doi.org/10.1038/s41598-020-62570-2\u003c/li\u003e\n\u003cli\u003eFigueroa-Mu\u0026ntilde;oz G, Molinet C, D\u0026iacute;az M, De los R\u0026iacute;os-Escalante P. Decapods associated with the Southern king crab (\u003cem\u003eLithodes santolla\u003c/em\u003e) fishery in Central Patagonia (44◦ S, Chile). J. Mar. Sci. Eng., 2021. 9: 1353. https://doi.org/10.3390/jmse9121353\u003c/li\u003e\n\u003cli\u003eGotelli NJ. Null model analysis of species co-occurrence patterns. Ecology. 2020, 81: 2606-2621. https://doi.org/10.1890/0012-9658(2000)081[2606:NMAOSC]2.0.CO;2\u003c/li\u003e\n\u003cli\u003eTiho S, Johens G. Co-occurrence of earthworms in urban surroundings: a null model analysis of community structure. European J. Soil Biol., 2007, 43: 84-90. https://doi.org/10.1016/j.ejsobi.2006.10.004\u003c/li\u003e\n\u003cli\u003eTondoh JE. Seasonal changes in earthworm diversity and community structure in Central C\u0026ocirc;te d\u0026rsquo;Ivoire. European J. Soil Biol., 2006, 42: supplement, 1, pp. s334-s340. https://doi.org/10.1016/j.ejsobi.2006.09.003\u003c/li\u003e\n\u003cli\u003eRetamal M. Los Dec\u0026aacute;podos Chilenos. CD-Rom. ETI (Amsterdam). Universidad de Concepci\u0026oacute;n; Springer: Berlin/Heidelberg, Germany. 2000.\u003c/li\u003e\n\u003cli\u003eWORMS Editorial Board. World Register of Marine Species. Available from https://www.marinespecies.org (Visited: 10\u003csup\u003eth\u003c/sup\u003e May 2024). 2024\u003c/li\u003e\n\u003cli\u003eUnderwood AJ, Chapman MG. Design and analysis in benthic surveys in environmental sampling. In: Eleftheriou A, McIntyre A, (Eds). Methods for the Study of Marine Benthos. Blackwell Science: Oxford, UK. pp. 1\u0026ndash;42. 2005.\u003c/li\u003e\n\u003cli\u003eManriquez PH. Muestreo y an\u0026aacute;lisis de comunidades intermareales de fondos duros. In: Castilla JC, Fari\u0026ntilde;a JM, Caama\u0026ntilde;o A, Eds. Programas de Monitoreo del Medio Mar\u0026iacute;timo Costero. Dise\u0026ntilde;os Experimentales, Muestreos, M\u0026eacute;todos de An\u0026aacute;lisis y Estad\u0026iacute;stica Asociada; Ediciones Pontificia Universidad Cat\u0026oacute;lica de Chile: Santiago, Chile; pp. 233\u0026ndash;256. 2021\u003c/li\u003e\n\u003cli\u003eGotelli NJ, Ellison AM. EcoSimR 1.00. Available at: http://www.uvm.edu/~ngotelli/EcoSim/EcoSim.html [accessed 05-Sep-2023]\u003c/li\u003e\n\u003cli\u003eR Development Core Team. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. 2025\u003c/li\u003e\n\u003cli\u003eCarvajal-Quintero JD, Escobar F, Alvarado F, Villa-Navarro FA, Jaramillo-Villa U, Maldonado-Ocampo JA. Variation in freshwater fish assemblages along a regional elevation gradient in the northern Andes, Colombia. Ecol Evol, 2015, 2: 2608-2620. https://doi.org/10.1002/ece3.1539\u003c/li\u003e\n\u003cli\u003eDe los R\u0026iacute;os-Escalante P, Figueroa-Mu\u0026ntilde;oz G, Retamal MA, Vega-Aguayo R, Esse C. Size overlap in intertidal decapod communities along the Chilean coast. Sci Mar, 2020, 84: 151-154. https://doi.org/10.3989/scimar.04973.14A\u003c/li\u003e\n\u003cli\u003eAndrade D, Ventura MJ, Stella C, De los R\u0026iacute;os-Escalante P. Size overlap in intertidal decapod communities on a central Chilean rocky beach (El Quisco, 32\u0026deg;24\u0026rsquo;S, Valpara\u0026iacute;so region, Chile). Crustaceana, 2022, 95: 489-495. https://doi.org/10.1163/15685403-bja10203 \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"intertidal decapods, null models, northern Patagonia, rocky shore","lastPublishedDoi":"10.21203/rs.3.rs-5921609/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5921609/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe intertidal decapods in continental Chile are characterized by its species sharing with Peruvian coast along practically all coast, being coexisting species that has not studied with details its interspecific interactions. The aim of the present study is apply null models for understand if the intertidal decapod community is random or not-random. The results revealed that species associations were random, due probably to many species repeated in samples, and the niche sharing results revealed that species reported do not share niche, and in consequence there is not interspecific competition. The obtained results partially agree with other similar observations for Chilean coast, and it would be explained due the oceanographic conditions.\u003c/p\u003e","manuscriptTitle":"Null models for understand intertidal decapods communities in North Patagonian beach (Pelluhuin, 41°S, Chile)","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-04 07:44:09","doi":"10.21203/rs.3.rs-5921609/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9bc20fd5-fb58-4a5c-ac62-6a2cf1b9f87c","owner":[],"postedDate":"April 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-23T07:54:16+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-04 07:44:09","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5921609","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5921609","identity":"rs-5921609","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}