Intertidal ecology Research Papers - Academia.edu (original) (raw)

2025, MARINE ECOLOGY PROGRESS SERIES

The invasive mytilid mussel Semimytilus algosus was first recorded on South African shores in 2009 and rapidly spread to occupy 500 km of the West Coast, where it dominates lower portions of the rocky shore. To identify mechanisms underlying the invasive success of S. algosus, the life-history parameters survivorship, reproductive output, recruitment, growth rate and shell and byssus strength were compared among S. algosus and another alien, Mytilus galloprovincialis, and the indigenous mussels Aulacomya atra and Choromytilus meridionalis. To standardise the effects of wave exposure and shore height on life history patterns, all observations and sampling were limited to the low shore at the research site, Bloubergstrand. The 4 mussel species employed very different means of maximising survival and/or space occupancy. S. algosus proved to be a typical r-selected species, with low survival due to its weak shell and byssal strength. Unexpectedly, it grew relatively slowly but had a high reproductive output and exceptionally high recruitment rate that largely account for its invasive success. This study therefore demonstrates how life-history traits influence the invasive success of alien species and allows predictions about their relative impacts on intertidal rocky shores.

2025, Ecologies

Within biogeographic regions, local communities are structured mainly by abiotic (environmental) filtering, external resource supply, and biotic interactions. In recent years, we investigated abiotic filtering and external resource supply as drivers of the latitudinal distribution of rocky intertidal species along the Atlantic Canadian coast in Nova Scotia. Here, we evaluate biotic interactions between the main sessile species groups. Specifically, we studied abundance relationships between seaweeds and filter-feeding invertebrates and between barnacles and mussels using data collected at mid-to-high intertidal elevations at eight wave-exposed locations every summer from 2014 to 2017. We assessed such relationships for each location and year through generalized additive modeling (GAM). Of the 32 relationships evaluated for seaweeds vs. filter-feeders, 31% were significant and consistently negative, suggesting competitive interactions. For barnacles vs. mussels, 25% of the relationships were significant and mostly positive, consistent with facilitation of mussel colonization by barnacles in harsh environments. The variability explained by these models was moderate, however, between around 10% and 50%. Overall, these results suggest that interactions between the studied sessile species groups are infrequent and, when present, relatively weak in these highly stressful habitats, which supports current ecological theory on community organization.

2025, URVIO. Revista Latinoamericana de Estudios de Seguridad

Resumen Introducción: el statu quo antártico podría cambiar. Los debates académicos del Norte global problematizan a China y Rusia, pero rara vez cuestionan las estrategias de sus propios países. Por ello, es necesario ampliar la perspectiva y promover análisis sobre la proyección de poder del Norte global en la Antártida. Objetivo: en esta investigación se analiza la geopolítica del grupo parlamentario británico All-Party Parliamentary Group for the Polar Regions (APPG for the Polar Regions) entre 2015 y 2024. Metodología: el análisis es cualitativo y se basa en fuentes primarias, estructuradas en tres preguntas: (1) ¿qué rol han atribuido a Punta Arenas en el contexto antártico?, (2) ¿cómo ha percibido el grupo los efectos del cambio climático en relación con la Antártida? y (3) ¿qué acciones internacionales ha impulsado en la región? Conclusiones los resultados muestran que el cambio climático es un tema central en la agenda del APPG for the Polar Regions; lo utilizan para fomentar la cooperación con científicos chilenos, justificar la presencia británica en la Antártida a través de la ciencia y fortalecer colaboraciones con Estados Unidos, mientras difunde una agenda climática en las Asambleas Parlamentarias Antárticas.

2025, International Journal of Fisheries and Aquatic Studies

The Kathiawar Peninsula's coastal areas, crucial for Arabian Sea trade, face significant human impact from industries and fishing, potentially affecting intertidal life. The study explores the population dynamics of the mudskipper Scartelaos histophorus in the coastal area of Bhavnagar district, Gujarat, India, focusing on its ecological status along the muddy-rocky intertidal coastline. The research, using the quadrat method, categorized data into four seasons from 2022-23 to 2023-24. Hathab Coast showed the highest density and abundance of Scartelaos histophorus due to muddy habitats, while Ghogha had significant mangrove coverage. The mudskipper population characteristics were strongly correlated with the quantity and thickness of the mud layer, as it constructs burrows in the muddy substrate. Scartelaos histophorus was predominantly found in the upper intertidal zone during low tides.

2025, Journal of the Marine Biological Association of the United Kingdom

The rocky shore of Punta Este, Golfo Nuevo (Patagonia, Argentina), was sampled by means of the standardized NaGISA (CoML) protocol, that was aimed to generate biodiversity baseline data in six levels, from high intertidal to 10 m depth. Based on the generated data, we analysed the benthic assemblage structure, species richness, mean abundance and the distribution pattern of invertebrate functional groups, typifying species in each intertidal and subtidal level. The intertidal sampled is exposed to extreme physical conditions higher than any other rocky shore system studied, with air temperature variation of 40°C during the year, maximum winds of 90 km/h and semidiurnal tides of 5 m amplitude; on the other hand subtidal presents less thermal variation (ΔT 10°C throughout the year) and more homogeneous physical conditions. We identified 64 taxa represented by six animal phyla: Mollusca, Arthropoda, Annelida (Polychaeta), Echinodermata, Cnidaria and Nemertea; and three algal phyla: Chl...

2025, Malaysian Journal of Fundamental and Applied Sciences

Environmental disturbance, whether natural or anthropogenic, may change the structure of macrobenthic assemblages (across various spatial and temporal scales) in terms of taxa richness, animal abundance, and animal biomass. Such changes may be used as an indicator and can provide a quantitative basis when assessing the levels of disturbance. This study is aimed to assess environmental disturbance caused by fish farming by linking chemical and physical parameters to differences in the structure of macrobenthic communities. The study sites comprised coastal water ecosystems in the Awerange Gulf, South Sulawesi, Indonesia. The study compared macrobenthic communities associated with polyculture and monoculture farming against reference sites. The tendency of reduction in their abundance occurred at polyculture and monoculture sites, compared to the reference site, i.e. 5882 ind.m-2, 3531 ind.m-2, 2112.5 ind.m-2, respectively. The results from multivariate and graphical methods using NMD...

2025, Aacl Bioflux

Rastrelliger brachysoma is the most commercially important small pelagic species of the family Scombridae from five fish landings in Jawa Island (Pelabuhan Ratu, Banten, Lampung, Jakarta and Banyuwangi). Mitochondrial DNA control region sequencing result among 211 individual was approximately 445 base pairs (bp) DNA segment and the nucleotide base composition (%) was 29.1 A; 32.9 T; 22.8 G; and 15.2 C. A total 64 haplotypes were identified. R. brachysoma from Pelabuhan Ratu have the highest number of haplotypes (25) and polymorphic site (24). The population of R. brachysoma was divided into two clusters. Cluster A (originate population from seas east Jawa) consisted of 53 haplotypes mostly from Banten and cluster B (population from the southern part of the South China Sea) consisted of 13 haplotypes mostly from Lampung. The nucleotide diversity (π) ranged from 0.009 (Banyuwangi) to 0.013 (Lampung) with average nucleotide diversity of 0.010 for all location. This fish population in I...

2025, Integrated Environmental Assessment and Management

Over the past decade, the scientific community has studied, experimented, and published a notable body of literature on the ecological enhancement of coastal and marine infrastructure (CMI). The Nature-Inclusive Design (NID) approach refers to methods and technologies that can be integrated into the design and construction of CMI to create a suitable habitat for native species (or communities) whose natural habitat has been degraded or reduced. To examine the compliance of new environmentally sensitive technologies with structural requirements and fiscal restraints, while providing ecosystem and habitat value, this paper presents the findings of a structural–economical–biological analysis of ecologically engineered Articulated Concrete Block Mattresses (ACBMs). To evaluate the structural and biological performance of the Ecological Articulated Concrete Block Mattresses, a pilot project was deployed in April 2017 at Port Everglades, Florida, USA, and evaluated against controls of adj...

2025, Ciencias Marinas

La playa rocosa es un ambiente frecuente en la zona norte de la costa Pacífica colombiana y debe su origen principalmente a la erosión de los acantilados por factores físicos y biológicos. Adicionalmente, la baja pendiente del sustrato y

2025, Diversity

This article documents the widespread absence of sessile species in bedrock intertidal habitats at the head of the St. Lawrence Estuary, a large macrotidal estuary located in eastern Canada. Extensive observations revealed that no seaweeds or sessile invertebrates occurred anywhere (including cracks and crevices) on substrate areas that become exposed to the air during low tides. Only one sessile species, a green filamentous alga, was found submerged in tidepools. The lack of truly marine sessile species is likely explained by the very low water salinity of this coast, while the absence of sessile freshwater species on intertidal substrates outside of tidepools likely responds to a combination of oligohaline conditions during high tides and daily exposures to the air during low tides, which freshwater species are typically not adapted to. Influences of winter ice scour and coastal suspended sediments are likely secondary. Experimental research could unravel the interactive effects of these abiotic stressors. Overall, this "intertidal desert" could be a useful model system to further explore the boundaries of life on our planet.

2025, Revista Mexicana De Biodiversidad

Updated checklist and zoogeographic remarks of benthic amphipods (Crustacea: Peracarida: Amphipoda) of two coastal lagoons in the western Lista de especies actualizada y notas zoogeográficas de anfípodos bentónicos (Crustacea: Peracarida:... more

2025, Western Indian Ocean Journal of Marine Science

The fish diversity of intertidal rock pools in the Glorieuses Islands was investigated using clove-oil anaesthetic. That method, is easy to use and safety is well adapted for this type of census. A total of thirty two species belonging to 14 families were sampled. Of these, 19 were observed as adults in most stations and represented the typical population of these intertidal pools, in particular the Blenniidae that presented the highest species richness and the Gobiidae, which were the most abundant. The 13 remaining species were only observed during their juvenile state and appeared to be only temporary residents. More than half of the species collected (17/32 spp) were not recorded during the previous ichthyofauna study at the Glorieuses islands using UVC, results that show the importance of the anaesthetic method that allows the collection of smaller-sized species that live inside the reef framework and are consequently more difficult to record.

2025, Journal of Experimental Marine Biology and Ecology

In New England, the blue mussel Mytilus edulis (Linnaeus) often lives infaunally on cabbie beaches in sheltered bays. We examined the lifestyle ofinfaunal mussels in sheltered bays and their relationship with the acorn barnacle Semibalanus balanoides (Linnaeus) living on cobbles. Results of transplant experiments with M. edulis suggest that heat stress associated with hard substrata restricts high intertidal mussels to infaunal habitats in sheltered bays. At high tidal heights, infaunal mussels are buffered from thermal stress and have higher survivorship and growth rates than epifaunal mussels on hard surfaces. Infaunal mussels bind cobbles together with byssal threads and reduce disturbance mortality to barnacles living on cobbles. Disturbance, however, was not a major source (< 10%) of barnacle mortality in the population studied. In contrast, infaunal mussel binding of cobbles and sediment was found to buffer cobbles from temperature extremes, insulating barnacles on cobbles from thermal stresses and substantially decreasing barnacle mortality on cobbles. Our work shows that the relationship between M. edulis and S. balanoides varies across habitats. Under benign thermal conditions at low intertidal heights and on wave-splashed shores, mussels outcompete barnacles for space on hard substrata. In contrast, at high tidal heights on thermally stressful cobble beaches, infauaal mussels may buffer-barnacles from thermal stress and increase barnacle survivorship. Our results support a growing body of literature which suggests that intra-and interspecific facilitation mechanisms may commonly be important in physically stressful environmen|s.

2025, Ecology

Positive interactions that result from neighbors buffering one another from stressful conditions are predictably important community forces in physically stressful habitats. Here, we examine the generality of this hypothesis in marine intertidal communities. Intertidal communities have historically played a large role in the development of community ecology since they occur across pronounced physical gradients and are easily manipulated. Positive interactions, however, have not been emphasized in studies of intertidal communities. We first review studies of intertidal marsh plant communities that suggest that positive interactions play a dominant role in the structure and dynamics of these common assemblages. We then present the results of an experimental manipulation on New England rocky shores that suggests that group benefits are as important in maintaining the upper intertidal limits of dominant spaceholders on rocky shores as the negative forces of competition and predation are in maintaining lower distributional limits. We conclude by discussing the generality and implications of our results. We argue that biogeographic biases have limited appreciation of the role played by positive interactions in intertidal communities. Most of the work that has formed the foundation of marine intertidal ecology was done in cool temperate habitats, whereas positive interactions driven by the amelioration of thermal or desiccation stresses are likely more important in warmer climates. We further argue that many important positive feedbacks operate at large spatial scales, not conducive to experimental study, and thus have escaped critical attention and general acceptance. We suggest that recognizing the role of positive interactions in communities may be key to understanding population and community processes in physically stressful habitats, many large-scale landscape processes, and uncovering long-suspected linkages between biodiversity and community stability.

2025, River Deltas Research - Recent Advances

The Jamapa River basin is located in the central region of the State of Veracruz, it is born in the Pico de Orizaba and connects with the Veracruz Reef System in the Gulf of Mexico, both protected natural areas. The lower part of the basin has the contribution of two important effluents, Arroyo Moreno, which is a protected natural area, strongly impacted due to municipal discharges from the metropolitan cities Veracruz-Boca del Río-Medellín. And the Estero, which is part of a complex aquatic system that discharges its waters from the Lagunar Mandinga system to the Gulf of Mexico. Currently, there is a diversity of chemical and biological compounds that the basin receives from different sources of freshwater pollution, such as industrial waste, sewage, agricultural and urban runoff, and the accumulation of sediments. The climatic seasons are the determining factors in the composition of its sediments, due to the force exerted on the bottom of the river by the increase in rainfall, th...

2025, Global Ecology and Biogeography

Aim To identify geographic locations where lethal temperatures and upper zonation limits of Mytilus californianus beds coincide and to determine the dominant climatic factor where lethal limits occur. Location Intertidal shores along 1500 km of the west coast of North America. Lethal temperatures for M. californianus were determined using temperature-controlled chambers in which both the magnitude and duration of exposure were manipulated. Field surveys of the shore level and solar exposure of upper zonation limits of mussel beds were conducted at 15 sites. Measurements from the lethal temperature studies and field surveys were used with a biophysical model of mussel body temperature to hindcast M. californianus mortality rates from 1997-2007. The critical lethal high body temperature was c. 38 °C. Hindcasts of mortality rates predicted that lethal temperatures occurred along the upper limits of the mussel bed at only two of the sites, Santa Cruz and Alegria, CA, USA, and daily maximum air temperature during low tide was the variable that distinguished these sites. Santa Cruz and Alegria were not adjacent to each other and not the most equatorward of the sites examined. Local upper zonation limits of the mussel M. californianus are determined by lethal high body temperatures at two of 15 locations, which means that alternative environmental factors are determining local zonation at most of the study sites. Mussel body temperature is driven by many physical variables, but air temperature was higher at Santa Cruz and Alegria than elsewhere making it the most likely factor driving the climatic sensitivity at local upper zonation limits. There was no significant evidence of local acclimation or local adaptation in this species. Some local zonation limits are more vulnerable to climate change than others, potentially causing the magnitude and timing of zonation shifts to differ even among closely situated sites.

2025, Global Change Biology

Species range boundaries are determined by a variety of factors of which climate is one of the most influential. As a result, climate change is expected to have a profound effect on organisms and ecosystems. However, the impacts of weather and climate are frequently modified by multiple nonclimatic factors. Therefore, the role of these nonclimatic factors needs to be examined in order to understand and predict future change. Marine intertidal ecosystems are exposed to heat extremes during warm, sunny, midday low tides. Thus, the timing of low tide, a nonclimatic factor, determines the potential contact intertidal invertebrates and algae have with heat extremes. We developed a method that quantifies the daily risk of high temperature extremes in the marine intertidal using solar elevations and spatially continuous tidal predictions. The frequency of 'risky days' is variable over time and space along the Pacific Coast of North America. Results show that at some sites the percentage of risky days in June can vary by 30% across years. In order to do a detailed analysis, we selected San Francisco as a study site. In San Francisco, May is the month with the greatest frequency of risky days, even though September is the month with the greatest frequency of high air temperature, ! 30 1C. These results indicate that marine intertidal organisms can be protected from high temperature extremes due to the timing of tides and local weather patterns. In addition, annual fluctuations in tides influence the frequency of intertidal zone exposures to high temperature extremes. Peaks in risk for heat extremes in the intertidal zone occur every 18 years, the length of the tidal epoch. These results suggest that nonclimatic variables can complicate predictions of shifts in species ranges due to climate change, but that mechanistic approaches can be used to produce predictions that include these factors.

2025, The American Naturalist

The body temperature of ectotherms is influenced by the interaction of abiotic conditions, morphology, and behavior. Al though organisms living in different thermal habitats may exhibit morphological plasticity or move from unfavorable locations, there are few examples of animals adjusting their thermal properties in response to short-term changes in local conditions. Here, we show that the intertidal sea star Pisaster ochraceus modulates its thermal inertia in response to prior thermal exposure. After exposure to high body temperature at low tide, sea stars increase the amount of colder than-air fluid in their coelomic cavity when submerged during high tide, resulting in a lower body temperature during the subsequent low tide. Moreover, this buffering capacity is more effective when seawater is cold during the previous high tide. This ability to modify the volume of coelomic fluid provides sea stars with a novel ther moregulatory "backup" when faced with prolonged exposure to el evated aerial temperatures.

2025

Coastal processes shape the coast into a variety of eye-catching and enticing landforms that attract people to marvel at, relax and enjoy coastal geomorphology. Field guides to explain these processes (and the geodiversity that results) to the general public and children are few and far between. In contrast, there is a relative wealth of resources and organised activities introducing people to coastal wildlife, especially on rocky shores. These biological resources typically focus on the biology and climatic controls on their distribution, rather than how the biology interacts with its physical habitat. As an outcome of two recent rock coast biogeomorphology projects (www.biogeomorph.org/coastal/coastaldefencedbiodiversity and www.biogeomorph.org/coastal/bioprotection ), we produced the first known guide to understanding how biogeomorphological processes help create coastal landforms. The ‘Shore Shapers’ guide (www.biogeomorph.org/coastal/shoreshapers) is designed to: a) bring bioti...

2025, Ecological Engineering

Concrete flood defences, erosion control structures, port and harbour facilities, and renewable energy infrastructure are increasingly being built in the world's coastal regions. There is, however, strong evidence to suggest that these structures are poor surrogates for natural rocky shores, often supporting assemblages with lower species abundance and diversity. Ecological engineering opportunities to enhance structures for biodiversity conservation (and other management goals) are therefore being sought, but the majority of work so far has concentrated on structural design features at the centimetremeter scale. We deployed concrete tiles with four easily-reproducible fine-scale (millimetre) textures (control, smoothed, grooved and exposed aggregate) in the intertidal zone to test opportunities for facilitating colonisation by a dominant ecosystem engineer (barnacles) relative to natural rock. Concrete texture had a significant effect on colonisation; smoothed tiles supported significantly fewer numbers of barnacles, and those with intermediate roughness (grooved concrete) significantly greater numbers, after one settlement season. The successful recruitment of early colonists is a critical stage in the development of more complex and diverse macrobenthic assemblages, especially those that provide physical habitat structure for other species. Our observations show that this can be facilitated relatively simply for barnacles on marine concrete by manipulating surface heterogeneity at a millimetre scale. Alongside other larger-scale manipulation (e.g. creating holes and pools), including fine-scale habitat heterogeneity in engineering designs can support international efforts to maximise the ecological value of marine urban infrastructure.

2025, Frontiers in Marine Science

2025, La UTN en la Antártida

La Antártida es el continente con las condiciones climáticas más severas de nuestro
planeta. Aunque a primera vista pueda parecer una vasta y desolada extensión de hielo,
es un ecosistema único que alberga una sorprendente biodiversidad. La vida en este
entorno extremo ha logrado adaptarse a condiciones que pocos lugares en la Tierra
pueden ofrecer: temperaturas bajo cero, vientos huracanados y largas temporadas de
oscuridad invernal. Sin embargo, esta riqueza natural se encuentra bajo amenaza debido
a los crecientes peligros ambientales.

2025, AES Bioflux

Agusan Marsh is the 1009 RAMSAR site, a wildlife sanctuary which harbour unique and pristine faunal species. It is considered one of the most ecologically significant wetland ecosystems in the Philippines. The study assessed species distribution and abundance using Geographic Information System Map in Agusan Marsh between Sago Palm and Terminalia Forest. Results showed a total of 322 individuals, 11 species and 6 families of amphibians documented. Of the 11 species of amphibians documented in Sago Palm and Terminalia Forest, 6 were Philippine endemics, 3 were invasive species in the area. Terminalia forest had the highest number of individuals documented during the conduct of the study. Sago Palm and Terminalia Forest have almost the same type of vegetation where amphibian species thrive most. Furthermore, ecological and environmental threats (conversion of Terminalia Forest to agricultural land, runoff of environmental pollutants, pesticides run-off and Kaingin or Slash and Burns) ...

2025, Zenodo (CERN European Organization for Nuclear Research)

Ulhas River Estuary (URE) sediment is highly silted. Boleophthalmus dussumieri (Val., 1837) is a mudskipper species of a common occurrence on the intertidal mudflats developed on either banks of URE. The present study recorded the various activities like burrow construction, feeding, territoriality and courtship, of B. dussumieri using scan and focal sampling method on the surface during tidal movements on the exposed mudflats of URE near Kolshet creek. Although the breeding and territoriality of B. dussumieri being normal, the other behavioral activities such as courtship, construction of burrows and survivorship were different as compared to the earlier observations by various experts. Breeding pairs preferred to develop burrows at spring tide limits. Burrows lacked chimneys and pit-pools. Juveniles remained without burrows and were found to secure position by penetration in loose soil during flood tide. Feeding on muddy surface was performed by strange straining behaviour.

2025, PeerJ

Recruitment is a key demographic step for the persistence of populations, so understanding its drivers has traditionally been a relevant goal of ecology. On marine rocky shores, coastal oceanography is an important driver of the recruitment of intertidal invertebrates that reproduce through pelagic larvae by affecting larval transport and delivery. The intermittent upwelling hypothesis (IUH) posits that coastal pelagic larvae are driven offshore under intense upwelling or to depths under intense downwelling, while weak upwelling allows larvae to stay near the shore, thereby facilitating intertidal recruitment. The IUH thus predicts a unimodal relationship between Bakun's upwelling index (BUI) and intertidal recruitment. The IUH has been supported by studies that plotted simultaneously single average values of recruitment and BUI for various coastal locations that collectively span downwelling to upwelling conditions. Based on its theoretical foundations, the IUH should also hold for a target location analyzed over the years provided enough interannual variation in BUI. On the Atlantic Canadian coast in Nova Scotia, upwelling varies interannually depending on wind patterns. Therefore, for a location that is representative of the abiotic and biotic conditions on this coast (Western Head), we tested the IUH by measuring annual intertidal barnacle recruitment and BUI for the pelagic larval season of barnacles for a period of 10 years (2014-2024). On this coast, BUI averaged for the barnacle larval season varied among years from mild downwelling to clear upwelling. Generalized additive modelling revealed a unimodal relationship between intertidal barnacle recruitment and BUI, thereby supporting the IUH. These results add this western ocean boundary to the known list of coastal systems where upwelling may influence intertidal invertebrate recruitment.

2025

Ascophyllum nodosum, better known as rockweed, is a commercially important, harvested intertidal brown alga species common in coastal Maine. Rockweed sea vegetable harvesting is a lucrative wild harvest fishery, that has also proved to be socially contentious and whose future management is uncertain 1,2 . A. nodosum is an intertidal macroalgal species that may also be impacted by sea level rise. Through a combination of biomass estimation, newspaper analysis, and interview data collection, this project seeks to (a) develop a typology of ecological services of A. nodosum in harvested and unharvested areas in the state of Maine; and (b) assess the stakeholder perspectives amidst the Ross v. Acadian Sea Plants Ltd. court case.

2025

La plupart des limicoles de l'hémisphère nord nichent dans la toundra circumpolaire et passent la période de non-reproduction sur les escales migratoires et les sites d'hivernage en domaine tempéré à tropical. Pendant cette... more

2025, Current Science

A study of the temporal effect on the abundance and diversity of intertidal rocky shore macroalgae revealed that there are ~70 species in the intertidal rocky shore of Anjuna (60 species) and Vagator (52 species) in Goa, India. Results showed that premonsoon (May) and post-monsoon (December) seasons favoured high species richness and abundance in both the study sites. In both cases, species diversity was low during the monsoon months (July and August). The study showed that low diversity might be a monsoonal effect and it coincides with the growth of Ulva and Porphyra species. The growth of opportunistic annuals brings about an ephemeral dominance of the macroalgal community by annual macroalgae. The driver is believed to be the nutrient influx from surface run-off, change in salinity and temperature due to high precipitation. The study showed that monsoon could have a role on the macroalgal community dynamics, and there was a strong correlation between diversity and biomass.

2025

In the present paper we describe fish assemblages of rocky intertidal pools and intertidal areas of sandy beaches of the Azores. Blennies (Parablennius sanguinolentus parvicornis, Coryphoblennius galerita and Lipophrys trigloides) constitute the dominant resident fish family in the intertidal pools. Thirteen species were encountered in intertidal pools. Richness is higher in the 3rd quarter of the year with 12 species and lower in the 1st and 2nd quarters with 8 species occurring in the samples. Diversity is also higher in the 3rd quarter. The small variation can mostly be attributed to transient species and juveniles using the shore as a nursery ground. Fifteen species occurred in the intertidal region of the protected shallow sandy beach of Porto Pim. This fish assemblage was dominated by juveniles of transient species. No resident species were present here. Richness and abundance were higher in 3rd and 4th quarters due to recruitment of juveniles, and the occurrence of migrant and transient species.

2025

Callichirus major (Say 1818), a burrowing shrimp inhabiting sandy beaches, presents increasing economic importance due to its use as live bait. Considering the complete absence of studies concerning its spatial distribution and density along the Brazilian Northeastern coast, this study investigate its ecology at a sandy beach, Piedade, just south from Recife, Pernambuco, Brazil (08°11’S and 34°55’W), from December 1999 to September 2000. Significant differences between burrow densities were found along the 10 sampling months, profiles and beach strata. The beach morphodynamics, measured as a profile of the vertical variation with time, was significantly related to burrow density variation at the upper strata. However, this influence was not reflected on the population structure.

2025, Frontiers in Ecology and Evolution

Heat waves have increased in frequency, duration, and magnitude in recent decades, causing mass mortality events in terrestrial and aquatic ecosystems. Arguably, mass mortalities of habitat-forming organisms – i.e., dominant sessile organisms that define habitats via their own physical structure – would be amongst the most dramatic impact of heat waves because of their negative, cascading consequences on their associated biodiversity. However, the resistance of habitat-forming organisms to heat waves can be enhanced if they associate with secondary habitat formers able to tolerate and modulate extreme heat levels. Here we show that a seaweed of the Porphyra/Pyropia (P/P) clade can shield primary habitat-forming mussels, Brachidontes rodriguezii, from the impacts of extreme temperatures in a southwestern Atlantic rocky intertidal shore. By means of P/P removal experiments and surveys, we illustrate that P/P cover (a) buffers temperatures in the understory mussel beds during daytime a...

2025

Rocky shores are considered heterogeneous environments due to their composition and structure. Therefore, they support numerous habitats for flora and fauna. Organisms found on rocky shores are facing intense physicochemical conditions during tidal changes from upper to lower intertidal zones. Total (N=1888) specimens were collected on seasonal basis from intertidal zone during low tide from two rocky sites of Karachi coast, Buleji and Sunehri during January 2017 to December 2017. The highest number of individuals (N=1041), were recorded from Buleji than Sunehri (N= 847). The seasonal abundance in Mollusca were measured as (36.84%), (63.67%), (25.08) and (40.38%) from Buleji while from Sunehri (45.16 %), (46.01%), (48.65) and (42.79 %) during pre-monsoon, south-west monsoon, post monsoon and north-east monsoon season respectively. Group Arthropoda, Mollusca and Echinodermata were shows the highest abundance of the species at both sites as compare to other groups. The highest diversity index from Sunehri (H'=0.64) was measured in north-east monsoon season meanwhile, (H'=0.61) was measured in post monsoon season from Buleji coast. Evenness index (J'=0.25) in pre-monsoon season from Buleji and (J'=0.28) in south-west monsoon season from Sunehri coast . Season shows the great abundance of species as compare to other seasons. No significant correlation was observed in between seasons, water temperature and salinity with macrofauna groups at both sites.

2025, Journal of the Marine Biological Association of the United Kingdom

Examining how variability in population abundance and distribution is allotted among different spatial scales can inform of processes that are likely to generate that variability. Results of studies dealing with scale issues in marine benthic communities suggest that variability is concentrated at small spatial scales (from tens of centimetres to few metres) and that spatial patterns of variation are consistent across ecosystems characterized by contrasting physical and biotic conditions, but this has not been formally tested. Here we quantified the variability in the distribution of intertidal rocky shore communities at a range of spatial scales, from tens of centimetres to thousands of kilometres, both in the NE Atlantic and the Mediterranean, and tested whether the observed patterns differed between the two basins. We focused on canopy-forming macroalgae and associated understorey assemblages in the low intertidal, and on the distribution of Patella limpets at mid intertidal leve...

2025

The Uttara Kannada District Sea Board lies between 74° 9' to 75°10' east longitude and 13° 55' to 15° 31' north latitude and extends over an area of 10,327 Sq. km. The district has three main and distinctive regions: the Coastlands, the Sahyadri range and Eastern margin where the tableland begins. The coastlines are the best-developed area with a high degree of economic development and a high density of population. It is in this region, Karwar, Ankola, Kumta, Honavar and Bhatkal taluks are located. The five important rivers of Uttara Kannada are Kalinadi, Gangavali, Aghanashini Sharavathi and Venktapur. The mangrove zone towards the river mouth, having higher salinity, is known as 'euhaline'. Along the coast of Uttara Kannada, the river mouths are rocky and with strong wave action, and not suitable for mangroves. This is unlike the deltaic river mouths of the east coast, where mangroves can grow luxuriantly. The euhaline zone has salinity range from 30 ppt to...

2025, Revista Escenarios Actuales. CESIM. Ejército de Chile

El cambio climático ha facilitado la navegación y prospecciones en
la banquisa del océano Ártico, y los países con intereses geopolíticos
y geoestratégicos en el área han venido dejando en evidencia el
desarrollo de capacidades militares para influir en el Círculo Polar.
Este artículo analiza las variables geográficas de los Estados con
proyección geofísica en ese espacio del planeta y revela cómo las
Las reclamaciones políticas o estratégicas en el Ártico se vinculan con
asuntos operacionales o con el empleo de la fuerza en procura de lograr objetivos nacionales. Sin embargo, el calentamiento global, los desafíos geofísicos y los intereses de los actores podrían marcar las diferencias en sus resultados y prolongar su condición de espacio global preservado para el futuro bienestar de la humanidad.

2025

La formación de las dotaciones antárticas del Ejército es un proceso de alta exigencia que debe preparar a las personas para operar, durante un año, en un ambiente distinto, hostil y esencialmente distante de las otras porciones territoriales chilenas. En este proceso, el estudio de los factores humanos y la influencia del factor sicológico ha sido esencial para el éxito de las misiones que a lo largo de 75 años, el Ejército de Chile, ha desplegado en el territorio antártico generando un sello distintivo y crucial, junto al aporte en la mantención de la soberanía, el apoyo a las operaciones militares distintas a la guerra, garantizando las condiciones de seguridad operacional para las diferentes dotaciones de científicos y personal civil que ha visitado el continente helado. El estudio e investigación de los factores humanos con énfasis en la psicología y la salud mental ha permitido crear un perfil psicológico claro y específico de nuestro personal militar y contribuido a generar nuevos conocimientos sobre el comportamiento humano en ambientes extremos, creando un ambiente seguro y resilente para las diferentes dotaciones que ha operado con eficiencia y versatilidad durante más de siete décadas.

2025, International Journal of Advance and Innovative Research

2025, Boletín de Investigaciones Marinas y Costeras

We studied the circadian behavior during the foraging activity of the gastropod Nerita scabricosta at low tide. To measure the behavior we recorded the traveled distance and corresponding duration during foraging activity, according to the dial periods (day and night) in April 2010. Gastropods were measured and weighed after fiishing their activity. Finally, values of air temperature and humidity were recorded for each sampling time and dial period. The foraging activity by N. scabricosta did not vary signifiantly between day and night. However duration increased at night, period characterized by lower temperature and higher humidity. In addition, it was found that the activity was continuous, regardless the period.

2025, Scientific Data

At a proximal level, the physiological impacts of global climate change on ectothermic organisms are manifest as changes in body temperatures. Especially for plants and animals exposed to direct solar radiation, body temperatures can be substantially different from air temperatures. We deployed biomimetic sensors that approximate the thermal characteristics of intertidal mussels at 71 sites worldwide, from 1998-present. Loggers recorded temperatures at 10–30 min intervals nearly continuously at multiple intertidal elevations. Comparisons against direct measurements of mussel tissue temperature indicated errors of ~2.0–2.5 °C, during daily fluctuations that often exceeded 15°–20 °C. Geographic patterns in thermal stress based on biomimetic logger measurements were generally far more complex than anticipated based only on ‘habitat-level’ measurements of air or sea surface temperature. This unique data set provides an opportunity to link physiological measurements with spatially- and t...

2025, Ecol Monogr

We explicitly quantified spatial and temporal patterns in the body temperature of an ecologically important species of intertidal invertebrate, the mussel Mytilus californianus, along the majority of its latitudinal range from Washington to southern California, USA. Using long-term (five years), high-frequency temperature records recorded at multiple sites, we tested the hypothesis that local ''modifying factors'' such as the timing of low tide in summer can lead to large-scale geographic mosaics of body temperature. Our results show that patterns of body temperature during aerial exposure at low tide vary in physiologically meaningful and often counterintuitive ways over large sections of this species' geographic range. We evaluated the spatial correlations among sites to explore how body temperatures change along the latitudinal gradient, and these analyses show that ''hot spots'' and ''cold spots'' exist where temperatures are hotter or colder than expected based on latitude. We identified four major hot spots and four cold spots along the entire geographic gradient with at least one hot spot and one cold spot in each of the three regions examined (Washington-Oregon, Central California, and Southern California). Temporal autocorrelation analysis of year-to-year consistency and temporal predictability in the mussel body temperatures revealed that southern animals experience higher levels of predictability in thermal signals than northern animals. We also explored the role of wave splash at a subset of sites and found that while average daily temperature extremes varied between sites with different levels of wave splash, yearly extreme temperatures were often similar, as were patterns of predictability. Our results suggest that regional patterns of tidal regime and local pattern of wave splash can overwhelm those of large-scale climate in driving patterns of body temperature, leading to complex thermal mosaics of temperature rather than simple latitudinal gradients. A narrow focus on population changes only at range margins may overlook climatically forced local extinctions and other population changes at sites well within a species range. Our results emphasize the importance of quantitatively examining biogeographic patterns in environmental variables at scales relevant to organisms, and in forecasting the impacts of changes in climate across species ranges.

2025, Journal of the Marine Biological Association of the United Kingdom

Coastal ecosystems are highly complex and driven by multiple environmental factors. To date we lack scientific evidence for the relative contribution of natural and anthropogenic drivers for the majority of marine habitats in order to adequately assess the role of different stressors across the European seas. Such relationship can be investigated by analysing the correlation between environmental variables and biotic patterns in multivariate space and taking into account non-linearities. Within the framework of the EMBOS (European Marine Biodiversity Observatory System) programme, hard bottom intertidal communities were sampled in a standardized way across European seas. Links between key natural and anthropogenic drivers and hard bottom communities were analysed using Boosted Regression Trees modelling. The study identified strong interregional variability and showed that patterns of hard bottom macroalgal and invertebrate communities were primarily a function of tidal regime, nutr...

2025, Arabian Journal of Geosciences

At Ras Kadhma embayment (north Kuwait), fabrics such as micrite envelopes, calcified microbial filaments, and micritic grain-to-grain bridges are observed in this modern sabkha environment in Kuwait Bay, associated with a tripartite facies classification. Three tidal zones were delineated by 8 vertical core samples, each marked by laterally diachronous units with different lithofacies and biofacies. Microbial populations (Lyngbya and Schizothrix), living within a distinct differentiated intertidal flat zone, were identified and their effects on sediments recorded. The extreme salinity, temperature, and chemical gradients in the shoreline environment have contributed to a microbial ecosystem that is trapping, binding, and biologically inducing CaCO 3 precipitation, producing a variety of sedimentary structures now conventionally regarded as MISS (microbially induced sedimentary structures). The microbial fabrics are preserved in aggregates within the intertidal to the continental vadose zone. Core samples and outcrops were collected and analyzed mineralogically, chemically, and microbiologically. Field mapping on a meter scale reveals a concentric zonation, subtidal, intertidal, and supratidal zones, distinguished by textural and biological differences. Distinct lithofacies reveal varying stages of biomineralization with optimum conditions developed in the intertidal and lagoon sediments enhanced by microbial populations. The results of the study contribute to the understanding of the complex interaction between microorganism forming mats, the tidal flat sediments, and the physical parameters that control this setting in Kadhma Bay. Recurring colonization of these siliciclastic sediments in the intertidal zone will be permanently terminated in the coming decades by advancing intertidal sand bars resulting from the destruction of the Tigris-Euphrates delta.

2025, Yorkshire History Quarterly - revised 2025

The tall four-storey octagonal chalk tower is 79 feet high is the oldest surviving lighthouse in England. It was built in 1674 as a lighthouse by Sir John Clayton and partner George Blake as a business venture. It was never used because suitable voluntary dues from passing ships were inadequate. Today it stands silent a gleaming monument on a golf course. The Beacon Tower Lighthouse is surrounded by modern posts and wire fences which separate it from the golf course. It is occasionally open to the public and can be viewed very easily from the road.

2025